yaml-to-dhall doesn't handle YAML 1.1 octal values correctly (used in Kubernetes)

[ggilmore]

yaml-to-dhall seems to simply strip leading 0's from octal values when converting them to dhall. This leads to problems when we need to render the dhall back to yaml again.

---

Consider the following Kubernetes Deployment yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  annotations:
    description: Collects metrics and aggregates them into graphs.
  labels:
    deploy: sourcegraph
    sourcegraph-resource-requires: no-cluster-admin
  name: prometheus
spec:
  minReadySeconds: 10
  replicas: 1
  revisionHistoryLimit: 10
  selector:
    matchLabels:
      app: prometheus
  strategy:
    type: Recreate
  template:
    metadata:
      labels:
        deploy: sourcegraph
        app: prometheus
    spec:
      containers:
      - image: index.docker.io/sourcegraph/prometheus:3.18.0@sha256:e970ed46bdf3f73477f95de9ada424ada4a24505239687ce0e474a62dac6c67b
        terminationMessagePolicy: FallbackToLogsOnError
        name: prometheus
        readinessProbe:
          httpGet:
            path: /-/ready
            port: 9090
          initialDelaySeconds: 30
          timeoutSeconds: 30
        livenessProbe:
          httpGet:
            path: /-/healthy
            port: 9090
          initialDelaySeconds: 30
          timeoutSeconds: 30
        ports:
        - containerPort: 9090
          name: http
        volumeMounts:
        - mountPath: /prometheus
          name: data
        - mountPath: /sg_prometheus_add_ons
          name: config
        # Prometheus is relied upon to monitor services for sending alerts to site admins when
        # something is wrong with Sourcegraph, thus its memory requests and limits are the same to
        # guarantee it has enough memory to perform its job reliably and prevent conflicts with
        # other pods on the same host node.
        #
        # Its average memory usage may be much lower than 3G if Sourcegraph itself does not have
        # much traffic, the 3G number chosen here is what works reliably on Sourcegraph.com with
        # lots of traffic.
        resources:
          limits:
            cpu: "2"
            memory: 3G
          requests:
            cpu: 500m
            memory: 3G
      securityContext:
        runAsUser: 0
      serviceAccountName: prometheus
      volumes:
      - name: data
        persistentVolumeClaim:
          claimName: prometheus
      - configMap:
          defaultMode: 0777
          name: prometheus
        name: config

Note the defaultMode of the configMap, 0777 (octal)

- configMap:
          defaultMode: 0777
          name: prometheus
        name: config

Converting it to dhall results in the following output

> yaml-to-dhall --version
1.2.1
> pbpaste | yaml-to-dhall '( https://raw.githubusercontent.com/dhall-lang/dhall-kubernetes/f4bf4b9ddf669f7149ec32150863a93d6c4b3ef1/1.18/schemas/io.k8s.api.apps.v1.Deployment.dhall ).Type'

{ apiVersion = "apps/v1"
, kind = "Deployment"
, metadata =
  { annotations = Some
      ( toMap
          { description = "Collects metrics and aggregates them into graphs." }
      )
  , clusterName = None Text
  , creationTimestamp = None Text
  , deletionGracePeriodSeconds = None Natural
  , deletionTimestamp = None Text
  , finalizers = None (List Text)
  , generateName = None Text
  , generation = None Natural
  , labels = Some
      ( toMap
          { sourcegraph-resource-requires = "no-cluster-admin"
          , deploy = "sourcegraph"
          }
      )
  , managedFields =
      None
        ( List
            { apiVersion : Text
            , fieldsType : Optional Text
            , fieldsV1 : Optional (List { mapKey : Text, mapValue : Text })
            , manager : Optional Text
            , operation : Optional Text
            , time : Optional Text
            }
        )
  , name = Some "prometheus"
  , namespace = None Text
  , ownerReferences =
      None
        ( List
            { apiVersion : Text
            , blockOwnerDeletion : Optional Bool
            , controller : Optional Bool
            , kind : Text
            , name : Text
            , uid : Text
            }
        )
  , resourceVersion = None Text
  , selfLink = None Text
  , uid = None Text
  }
, spec = Some
  { minReadySeconds = Some 10
  , paused = None Bool
  , progressDeadlineSeconds = None Natural
  , replicas = Some 1
  , revisionHistoryLimit = Some 10
  , selector =
    { matchExpressions =
        None
          (List { key : Text, operator : Text, values : Optional (List Text) })
    , matchLabels = Some (toMap { app = "prometheus" })
    }
  , strategy = Some
    { rollingUpdate =
        None
          { maxSurge : Optional < Int : Natural | String : Text >
          , maxUnavailable : Optional < Int : Natural | String : Text >
          }
    , type = Some "Recreate"
    }
  , template =
    { metadata =
      { annotations = None (List { mapKey : Text, mapValue : Text })
      , clusterName = None Text
      , creationTimestamp = None Text
      , deletionGracePeriodSeconds = None Natural
      , deletionTimestamp = None Text
      , finalizers = None (List Text)
      , generateName = None Text
      , generation = None Natural
      , labels = Some (toMap { app = "prometheus", deploy = "sourcegraph" })
      , managedFields =
          None
            ( List
                { apiVersion : Text
                , fieldsType : Optional Text
                , fieldsV1 : Optional (List { mapKey : Text, mapValue : Text })
                , manager : Optional Text
                , operation : Optional Text
                , time : Optional Text
                }
            )
      , name = None Text
      , namespace = None Text
      , ownerReferences =
          None
            ( List
                { apiVersion : Text
                , blockOwnerDeletion : Optional Bool
                , controller : Optional Bool
                , kind : Text
                , name : Text
                , uid : Text
                }
            )
      , resourceVersion = None Text
      , selfLink = None Text
      , uid = None Text
      }
    , spec = Some
      { activeDeadlineSeconds = None Natural
      , affinity =
          None
            { nodeAffinity :
                Optional
                  { preferredDuringSchedulingIgnoredDuringExecution :
                      Optional
                        ( List
                            { preference :
                                { matchExpressions :
                                    Optional
                                      ( List
                                          { key : Text
                                          , operator : Text
                                          , values : Optional (List Text)
                                          }
                                      )
                                , matchFields :
                                    Optional
                                      ( List
                                          { key : Text
                                          , operator : Text
                                          , values : Optional (List Text)
                                          }
                                      )
                                }
                            , weight : Natural
                            }
                        )
                  , requiredDuringSchedulingIgnoredDuringExecution :
                      Optional
                        { nodeSelectorTerms :
                            List
                              { matchExpressions :
                                  Optional
                                    ( List
                                        { key : Text
                                        , operator : Text
                                        , values : Optional (List Text)
                                        }
                                    )
                              , matchFields :
                                  Optional
                                    ( List
                                        { key : Text
                                        , operator : Text
                                        , values : Optional (List Text)
                                        }
                                    )
                              }
                        }
                  }
            , podAffinity :
                Optional
                  { preferredDuringSchedulingIgnoredDuringExecution :
                      Optional
                        ( List
                            { podAffinityTerm :
                                { labelSelector :
                                    Optional
                                      { matchExpressions :
                                          Optional
                                            ( List
                                                { key : Text
                                                , operator : Text
                                                , values : Optional (List Text)
                                                }
                                            )
                                      , matchLabels :
                                          Optional
                                            ( List
                                                { mapKey : Text
                                                , mapValue : Text
                                                }
                                            )
                                      }
                                , namespaces : Optional (List Text)
                                , topologyKey : Text
                                }
                            , weight : Natural
                            }
                        )
                  , requiredDuringSchedulingIgnoredDuringExecution :
                      Optional
                        ( List
                            { labelSelector :
                                Optional
                                  { matchExpressions :
                                      Optional
                                        ( List
                                            { key : Text
                                            , operator : Text
                                            , values : Optional (List Text)
                                            }
                                        )
                                  , matchLabels :
                                      Optional
                                        ( List
                                            { mapKey : Text, mapValue : Text }
                                        )
                                  }
                            , namespaces : Optional (List Text)
                            , topologyKey : Text
                            }
                        )
                  }
            , podAntiAffinity :
                Optional
                  { preferredDuringSchedulingIgnoredDuringExecution :
                      Optional
                        ( List
                            { podAffinityTerm :
                                { labelSelector :
                                    Optional
                                      { matchExpressions :
                                          Optional
                                            ( List
                                                { key : Text
                                                , operator : Text
                                                , values : Optional (List Text)
                                                }
                                            )
                                      , matchLabels :
                                          Optional
                                            ( List
                                                { mapKey : Text
                                                , mapValue : Text
                                                }
                                            )
                                      }
                                , namespaces : Optional (List Text)
                                , topologyKey : Text
                                }
                            , weight : Natural
                            }
                        )
                  , requiredDuringSchedulingIgnoredDuringExecution :
                      Optional
                        ( List
                            { labelSelector :
                                Optional
                                  { matchExpressions :
                                      Optional
                                        ( List
                                            { key : Text
                                            , operator : Text
                                            , values : Optional (List Text)
                                            }
                                        )
                                  , matchLabels :
                                      Optional
                                        ( List
                                            { mapKey : Text, mapValue : Text }
                                        )
                                  }
                            , namespaces : Optional (List Text)
                            , topologyKey : Text
                            }
                        )
                  }
            }
      , automountServiceAccountToken = None Bool
      , containers =
        [ { args = None (List Text)
          , command = None (List Text)
          , env =
              None
                ( List
                    { name : Text
                    , value : Optional Text
                    , valueFrom :
                        Optional
                          { configMapKeyRef :
                              Optional
                                { key : Text
                                , name : Optional Text
                                , optional : Optional Bool
                                }
                          , fieldRef :
                              Optional
                                { apiVersion : Optional Text, fieldPath : Text }
                          , resourceFieldRef :
                              Optional
                                { containerName : Optional Text
                                , divisor : Optional Text
                                , resource : Text
                                }
                          , secretKeyRef :
                              Optional
                                { key : Text
                                , name : Optional Text
                                , optional : Optional Bool
                                }
                          }
                    }
                )
          , envFrom =
              None
                ( List
                    { configMapRef :
                        Optional
                          { name : Optional Text, optional : Optional Bool }
                    , prefix : Optional Text
                    , secretRef :
                        Optional
                          { name : Optional Text, optional : Optional Bool }
                    }
                )
          , image = Some
              "index.docker.io/sourcegraph/prometheus:3.18.0@sha256:e970ed46bdf3f73477f95de9ada424ada4a24505239687ce0e474a62dac6c67b"
          , imagePullPolicy = None Text
          , lifecycle =
              None
                { postStart :
                    Optional
                      { exec : Optional { command : Optional (List Text) }
                      , httpGet :
                          Optional
                            { host : Optional Text
                            , httpHeaders :
                                Optional (List { name : Text, value : Text })
                            , path : Optional Text
                            , port : < Int : Natural | String : Text >
                            , scheme : Optional Text
                            }
                      , tcpSocket :
                          Optional
                            { host : Optional Text
                            , port : < Int : Natural | String : Text >
                            }
                      }
                , preStop :
                    Optional
                      { exec : Optional { command : Optional (List Text) }
                      , httpGet :
                          Optional
                            { host : Optional Text
                            , httpHeaders :
                                Optional (List { name : Text, value : Text })
                            , path : Optional Text
                            , port : < Int : Natural | String : Text >
                            , scheme : Optional Text
                            }
                      , tcpSocket :
                          Optional
                            { host : Optional Text
                            , port : < Int : Natural | String : Text >
                            }
                      }
                }
          , livenessProbe = Some
            { exec = None { command : Optional (List Text) }
            , failureThreshold = None Natural
            , httpGet = Some
              { host = None Text
              , httpHeaders = None (List { name : Text, value : Text })
              , path = Some "/-/healthy"
              , port = < Int : Natural | String : Text >.Int 9090
              , scheme = None Text
              }
            , initialDelaySeconds = Some 30
            , periodSeconds = None Natural
            , successThreshold = None Natural
            , tcpSocket =
                None
                  { host : Optional Text
                  , port : < Int : Natural | String : Text >
                  }
            , timeoutSeconds = Some 30
            }
          , name = "prometheus"
          , ports = Some
            [ { containerPort = 9090
              , hostIP = None Text
              , hostPort = None Natural
              , name = Some "http"
              , protocol = None Text
              }
            ]
          , readinessProbe = Some
            { exec = None { command : Optional (List Text) }
            , failureThreshold = None Natural
            , httpGet = Some
              { host = None Text
              , httpHeaders = None (List { name : Text, value : Text })
              , path = Some "/-/ready"
              , port = < Int : Natural | String : Text >.Int 9090
              , scheme = None Text
              }
            , initialDelaySeconds = Some 30
            , periodSeconds = None Natural
            , successThreshold = None Natural
            , tcpSocket =
                None
                  { host : Optional Text
                  , port : < Int : Natural | String : Text >
                  }
            , timeoutSeconds = Some 30
            }
          , resources = Some
            { limits = Some (toMap { memory = "3G", cpu = "2" })
            , requests = Some (toMap { memory = "3G", cpu = "500m" })
            }
          , securityContext =
              None
                { allowPrivilegeEscalation : Optional Bool
                , capabilities :
                    Optional
                      { add : Optional (List Text)
                      , drop : Optional (List Text)
                      }
                , privileged : Optional Bool
                , procMount : Optional Text
                , readOnlyRootFilesystem : Optional Bool
                , runAsGroup : Optional Natural
                , runAsNonRoot : Optional Bool
                , runAsUser : Optional Natural
                , seLinuxOptions :
                    Optional
                      { level : Optional Text
                      , role : Optional Text
                      , type : Optional Text
                      , user : Optional Text
                      }
                , windowsOptions :
                    Optional
                      { gmsaCredentialSpec : Optional Text
                      , gmsaCredentialSpecName : Optional Text
                      , runAsUserName : Optional Text
                      }
                }
          , startupProbe =
              None
                { exec : Optional { command : Optional (List Text) }
                , failureThreshold : Optional Natural
                , httpGet :
                    Optional
                      { host : Optional Text
                      , httpHeaders :
                          Optional (List { name : Text, value : Text })
                      , path : Optional Text
                      , port : < Int : Natural | String : Text >
                      , scheme : Optional Text
                      }
                , initialDelaySeconds : Optional Natural
                , periodSeconds : Optional Natural
                , successThreshold : Optional Natural
                , tcpSocket :
                    Optional
                      { host : Optional Text
                      , port : < Int : Natural | String : Text >
                      }
                , timeoutSeconds : Optional Natural
                }
          , stdin = None Bool
          , stdinOnce = None Bool
          , terminationMessagePath = None Text
          , terminationMessagePolicy = Some "FallbackToLogsOnError"
          , tty = None Bool
          , volumeDevices = None (List { devicePath : Text, name : Text })
          , volumeMounts = Some
            [ { mountPath = "/prometheus"
              , mountPropagation = None Text
              , name = "data"
              , readOnly = None Bool
              , subPath = None Text
              , subPathExpr = None Text
              }
            , { mountPath = "/sg_prometheus_add_ons"
              , mountPropagation = None Text
              , name = "config"
              , readOnly = None Bool
              , subPath = None Text
              , subPathExpr = None Text
              }
            ]
          , workingDir = None Text
          }
        ]
      , dnsConfig =
          None
            { nameservers : Optional (List Text)
            , options :
                Optional (List { name : Optional Text, value : Optional Text })
            , searches : Optional (List Text)
            }
      , dnsPolicy = None Text
      , enableServiceLinks = None Bool
      , ephemeralContainers =
          None
            ( List
                { args : Optional (List Text)
                , command : Optional (List Text)
                , env :
                    Optional
                      ( List
                          { name : Text
                          , value : Optional Text
                          , valueFrom :
                              Optional
                                { configMapKeyRef :
                                    Optional
                                      { key : Text
                                      , name : Optional Text
                                      , optional : Optional Bool
                                      }
                                , fieldRef :
                                    Optional
                                      { apiVersion : Optional Text
                                      , fieldPath : Text
                                      }
                                , resourceFieldRef :
                                    Optional
                                      { containerName : Optional Text
                                      , divisor : Optional Text
                                      , resource : Text
                                      }
                                , secretKeyRef :
                                    Optional
                                      { key : Text
                                      , name : Optional Text
                                      , optional : Optional Bool
                                      }
                                }
                          }
                      )
                , envFrom :
                    Optional
                      ( List
                          { configMapRef :
                              Optional
                                { name : Optional Text
                                , optional : Optional Bool
                                }
                          , prefix : Optional Text
                          , secretRef :
                              Optional
                                { name : Optional Text
                                , optional : Optional Bool
                                }
                          }
                      )
                , image : Optional Text
                , imagePullPolicy : Optional Text
                , lifecycle :
                    Optional
                      { postStart :
                          Optional
                            { exec : Optional { command : Optional (List Text) }
                            , httpGet :
                                Optional
                                  { host : Optional Text
                                  , httpHeaders :
                                      Optional
                                        (List { name : Text, value : Text })
                                  , path : Optional Text
                                  , port : < Int : Natural | String : Text >
                                  , scheme : Optional Text
                                  }
                            , tcpSocket :
                                Optional
                                  { host : Optional Text
                                  , port : < Int : Natural | String : Text >
                                  }
                            }
                      , preStop :
                          Optional
                            { exec : Optional { command : Optional (List Text) }
                            , httpGet :
                                Optional
                                  { host : Optional Text
                                  , httpHeaders :
                                      Optional
                                        (List { name : Text, value : Text })
                                  , path : Optional Text
                                  , port : < Int : Natural | String : Text >
                                  , scheme : Optional Text
                                  }
                            , tcpSocket :
                                Optional
                                  { host : Optional Text
                                  , port : < Int : Natural | String : Text >
                                  }
                            }
                      }
                , livenessProbe :
                    Optional
                      { exec : Optional { command : Optional (List Text) }
                      , failureThreshold : Optional Natural
                      , httpGet :
                          Optional
                            { host : Optional Text
                            , httpHeaders :
                                Optional (List { name : Text, value : Text })
                            , path : Optional Text
                            , port : < Int : Natural | String : Text >
                            , scheme : Optional Text
                            }
                      , initialDelaySeconds : Optional Natural
                      , periodSeconds : Optional Natural
                      , successThreshold : Optional Natural
                      , tcpSocket :
                          Optional
                            { host : Optional Text
                            , port : < Int : Natural | String : Text >
                            }
                      , timeoutSeconds : Optional Natural
                      }
                , name : Text
                , ports :
                    Optional
                      ( List
                          { containerPort : Natural
                          , hostIP : Optional Text
                          , hostPort : Optional Natural
                          , name : Optional Text
                          , protocol : Optional Text
                          }
                      )
                , readinessProbe :
                    Optional
                      { exec : Optional { command : Optional (List Text) }
                      , failureThreshold : Optional Natural
                      , httpGet :
                          Optional
                            { host : Optional Text
                            , httpHeaders :
                                Optional (List { name : Text, value : Text })
                            , path : Optional Text
                            , port : < Int : Natural | String : Text >
                            , scheme : Optional Text
                            }
                      , initialDelaySeconds : Optional Natural
                      , periodSeconds : Optional Natural
                      , successThreshold : Optional Natural
                      , tcpSocket :
                          Optional
                            { host : Optional Text
                            , port : < Int : Natural | String : Text >
                            }
                      , timeoutSeconds : Optional Natural
                      }
                , resources :
                    Optional
                      { limits :
                          Optional (List { mapKey : Text, mapValue : Text })
                      , requests :
                          Optional (List { mapKey : Text, mapValue : Text })
                      }
                , securityContext :
                    Optional
                      { allowPrivilegeEscalation : Optional Bool
                      , capabilities :
                          Optional
                            { add : Optional (List Text)
                            , drop : Optional (List Text)
                            }
                      , privileged : Optional Bool
                      , procMount : Optional Text
                      , readOnlyRootFilesystem : Optional Bool
                      , runAsGroup : Optional Natural
                      , runAsNonRoot : Optional Bool
                      , runAsUser : Optional Natural
                      , seLinuxOptions :
                          Optional
                            { level : Optional Text
                            , role : Optional Text
                            , type : Optional Text
                            , user : Optional Text
                            }
                      , windowsOptions :
                          Optional
                            { gmsaCredentialSpec : Optional Text
                            , gmsaCredentialSpecName : Optional Text
                            , runAsUserName : Optional Text
                            }
                      }
                , startupProbe :
                    Optional
                      { exec : Optional { command : Optional (List Text) }
                      , failureThreshold : Optional Natural
                      , httpGet :
                          Optional
                            { host : Optional Text
                            , httpHeaders :
                                Optional (List { name : Text, value : Text })
                            , path : Optional Text
                            , port : < Int : Natural | String : Text >
                            , scheme : Optional Text
                            }
                      , initialDelaySeconds : Optional Natural
                      , periodSeconds : Optional Natural
                      , successThreshold : Optional Natural
                      , tcpSocket :
                          Optional
                            { host : Optional Text
                            , port : < Int : Natural | String : Text >
                            }
                      , timeoutSeconds : Optional Natural
                      }
                , stdin : Optional Bool
                , stdinOnce : Optional Bool
                , targetContainerName : Optional Text
                , terminationMessagePath : Optional Text
                , terminationMessagePolicy : Optional Text
                , tty : Optional Bool
                , volumeDevices :
                    Optional (List { devicePath : Text, name : Text })
                , volumeMounts :
                    Optional
                      ( List
                          { mountPath : Text
                          , mountPropagation : Optional Text
                          , name : Text
                          , readOnly : Optional Bool
                          , subPath : Optional Text
                          , subPathExpr : Optional Text
                          }
                      )
                , workingDir : Optional Text
                }
            )
      , hostAliases =
          None (List { hostnames : Optional (List Text), ip : Optional Text })
      , hostIPC = None Bool
      , hostNetwork = None Bool
      , hostPID = None Bool
      , hostname = None Text
      , imagePullSecrets = None (List { name : Optional Text })
      , initContainers =
          None
            ( List
                { args : Optional (List Text)
                , command : Optional (List Text)
                , env :
                    Optional
                      ( List
                          { name : Text
                          , value : Optional Text
                          , valueFrom :
                              Optional
                                { configMapKeyRef :
                                    Optional
                                      { key : Text
                                      , name : Optional Text
                                      , optional : Optional Bool
                                      }
                                , fieldRef :
                                    Optional
                                      { apiVersion : Optional Text
                                      , fieldPath : Text
                                      }
                                , resourceFieldRef :
                                    Optional
                                      { containerName : Optional Text
                                      , divisor : Optional Text
                                      , resource : Text
                                      }
                                , secretKeyRef :
                                    Optional
                                      { key : Text
                                      , name : Optional Text
                                      , optional : Optional Bool
                                      }
                                }
                          }
                      )
                , envFrom :
                    Optional
                      ( List
                          { configMapRef :
                              Optional
                                { name : Optional Text
                                , optional : Optional Bool
                                }
                          , prefix : Optional Text
                          , secretRef :
                              Optional
                                { name : Optional Text
                                , optional : Optional Bool
                                }
                          }
                      )
                , image : Optional Text
                , imagePullPolicy : Optional Text
                , lifecycle :
                    Optional
                      { postStart :
                          Optional
                            { exec : Optional { command : Optional (List Text) }
                            , httpGet :
                                Optional
                                  { host : Optional Text
                                  , httpHeaders :
                                      Optional
                                        (List { name : Text, value : Text })
                                  , path : Optional Text
                                  , port : < Int : Natural | String : Text >
                                  , scheme : Optional Text
                                  }
                            , tcpSocket :
                                Optional
                                  { host : Optional Text
                                  , port : < Int : Natural | String : Text >
                                  }
                            }
                      , preStop :
                          Optional
                            { exec : Optional { command : Optional (List Text) }
                            , httpGet :
                                Optional
                                  { host : Optional Text
                                  , httpHeaders :
                                      Optional
                                        (List { name : Text, value : Text })
                                  , path : Optional Text
                                  , port : < Int : Natural | String : Text >
                                  , scheme : Optional Text
                                  }
                            , tcpSocket :
                                Optional
                                  { host : Optional Text
                                  , port : < Int : Natural | String : Text >
                                  }
                            }
                      }
                , livenessProbe :
                    Optional
                      { exec : Optional { command : Optional (List Text) }
                      , failureThreshold : Optional Natural
                      , httpGet :
                          Optional
                            { host : Optional Text
                            , httpHeaders :
                                Optional (List { name : Text, value : Text })
                            , path : Optional Text
                            , port : < Int : Natural | String : Text >
                            , scheme : Optional Text
                            }
                      , initialDelaySeconds : Optional Natural
                      , periodSeconds : Optional Natural
                      , successThreshold : Optional Natural
                      , tcpSocket :
                          Optional
                            { host : Optional Text
                            , port : < Int : Natural | String : Text >
                            }
                      , timeoutSeconds : Optional Natural
                      }
                , name : Text
                , ports :
                    Optional
                      ( List
                          { containerPort : Natural
                          , hostIP : Optional Text
                          , hostPort : Optional Natural
                          , name : Optional Text
                          , protocol : Optional Text
                          }
                      )
                , readinessProbe :
                    Optional
                      { exec : Optional { command : Optional (List Text) }
                      , failureThreshold : Optional Natural
                      , httpGet :
                          Optional
                            { host : Optional Text
                            , httpHeaders :
                                Optional (List { name : Text, value : Text })
                            , path : Optional Text
                            , port : < Int : Natural | String : Text >
                            , scheme : Optional Text
                            }
                      , initialDelaySeconds : Optional Natural
                      , periodSeconds : Optional Natural
                      , successThreshold : Optional Natural
                      , tcpSocket :
                          Optional
                            { host : Optional Text
                            , port : < Int : Natural | String : Text >
                            }
                      , timeoutSeconds : Optional Natural
                      }
                , resources :
                    Optional
                      { limits :
                          Optional (List { mapKey : Text, mapValue : Text })
                      , requests :
                          Optional (List { mapKey : Text, mapValue : Text })
                      }
                , securityContext :
                    Optional
                      { allowPrivilegeEscalation : Optional Bool
                      , capabilities :
                          Optional
                            { add : Optional (List Text)
                            , drop : Optional (List Text)
                            }
                      , privileged : Optional Bool
                      , procMount : Optional Text
                      , readOnlyRootFilesystem : Optional Bool
                      , runAsGroup : Optional Natural
                      , runAsNonRoot : Optional Bool
                      , runAsUser : Optional Natural
                      , seLinuxOptions :
                          Optional
                            { level : Optional Text
                            , role : Optional Text
                            , type : Optional Text
                            , user : Optional Text
                            }
                      , windowsOptions :
                          Optional
                            { gmsaCredentialSpec : Optional Text
                            , gmsaCredentialSpecName : Optional Text
                            , runAsUserName : Optional Text
                            }
                      }
                , startupProbe :
                    Optional
                      { exec : Optional { command : Optional (List Text) }
                      , failureThreshold : Optional Natural
                      , httpGet :
                          Optional
                            { host : Optional Text
                            , httpHeaders :
                                Optional (List { name : Text, value : Text })
                            , path : Optional Text
                            , port : < Int : Natural | String : Text >
                            , scheme : Optional Text
                            }
                      , initialDelaySeconds : Optional Natural
                      , periodSeconds : Optional Natural
                      , successThreshold : Optional Natural
                      , tcpSocket :
                          Optional
                            { host : Optional Text
                            , port : < Int : Natural | String : Text >
                            }
                      , timeoutSeconds : Optional Natural
                      }
                , stdin : Optional Bool
                , stdinOnce : Optional Bool
                , terminationMessagePath : Optional Text
                , terminationMessagePolicy : Optional Text
                , tty : Optional Bool
                , volumeDevices :
                    Optional (List { devicePath : Text, name : Text })
                , volumeMounts :
                    Optional
                      ( List
                          { mountPath : Text
                          , mountPropagation : Optional Text
                          , name : Text
                          , readOnly : Optional Bool
                          , subPath : Optional Text
                          , subPathExpr : Optional Text
                          }
                      )
                , workingDir : Optional Text
                }
            )
      , nodeName = None Text
      , nodeSelector = None (List { mapKey : Text, mapValue : Text })
      , overhead = None (List { mapKey : Text, mapValue : Text })
      , preemptionPolicy = None Text
      , priority = None Natural
      , priorityClassName = None Text
      , readinessGates = None (List { conditionType : Text })
      , restartPolicy = None Text
      , runtimeClassName = None Text
      , schedulerName = None Text
      , securityContext = Some
        { fsGroup = None Natural
        , fsGroupChangePolicy = None Text
        , runAsGroup = None Natural
        , runAsNonRoot = None Bool
        , runAsUser = Some 0
        , seLinuxOptions =
            None
              { level : Optional Text
              , role : Optional Text
              , type : Optional Text
              , user : Optional Text
              }
        , supplementalGroups = None (List Natural)
        , sysctls = None (List { name : Text, value : Text })
        , windowsOptions =
            None
              { gmsaCredentialSpec : Optional Text
              , gmsaCredentialSpecName : Optional Text
              , runAsUserName : Optional Text
              }
        }
      , serviceAccount = None Text
      , serviceAccountName = Some "prometheus"
      , shareProcessNamespace = None Bool
      , subdomain = None Text
      , terminationGracePeriodSeconds = None Natural
      , tolerations =
          None
            ( List
                { effect : Optional Text
                , key : Optional Text
                , operator : Optional Text
                , tolerationSeconds : Optional Natural
                , value : Optional Text
                }
            )
      , topologySpreadConstraints =
          None
            ( List
                { labelSelector :
                    Optional
                      { matchExpressions :
                          Optional
                            ( List
                                { key : Text
                                , operator : Text
                                , values : Optional (List Text)
                                }
                            )
                      , matchLabels :
                          Optional (List { mapKey : Text, mapValue : Text })
                      }
                , maxSkew : Natural
                , topologyKey : Text
                , whenUnsatisfiable : Text
                }
            )
      , volumes = Some
        [ { awsElasticBlockStore =
              None
                { fsType : Optional Text
                , partition : Optional Natural
                , readOnly : Optional Bool
                , volumeID : Text
                }
          , azureDisk =
              None
                { cachingMode : Optional Text
                , diskName : Text
                , diskURI : Text
                , fsType : Optional Text
                , kind : Text
                , readOnly : Optional Bool
                }
          , azureFile =
              None
                { readOnly : Optional Bool
                , secretName : Text
                , shareName : Text
                }
          , cephfs =
              None
                { monitors : List Text
                , path : Optional Text
                , readOnly : Optional Bool
                , secretFile : Optional Text
                , secretRef : Optional { name : Optional Text }
                , user : Optional Text
                }
          , cinder =
              None
                { fsType : Optional Text
                , readOnly : Optional Bool
                , secretRef : Optional { name : Optional Text }
                , volumeID : Text
                }
          , configMap =
              None
                { defaultMode : Optional Natural
                , items :
                    Optional
                      ( List
                          { key : Text, mode : Optional Natural, path : Text }
                      )
                , name : Optional Text
                , optional : Optional Bool
                }
          , csi =
              None
                { driver : Text
                , fsType : Optional Text
                , nodePublishSecretRef : Optional { name : Optional Text }
                , readOnly : Optional Bool
                , volumeAttributes :
                    Optional (List { mapKey : Text, mapValue : Text })
                }
          , downwardAPI =
              None
                { defaultMode : Optional Natural
                , items :
                    Optional
                      ( List
                          { fieldRef :
                              Optional
                                { apiVersion : Optional Text, fieldPath : Text }
                          , mode : Optional Natural
                          , path : Text
                          , resourceFieldRef :
                              Optional
                                { containerName : Optional Text
                                , divisor : Optional Text
                                , resource : Text
                                }
                          }
                      )
                }
          , emptyDir =
              None { medium : Optional Text, sizeLimit : Optional Text }
          , fc =
              None
                { fsType : Optional Text
                , lun : Optional Natural
                , readOnly : Optional Bool
                , targetWWNs : Optional (List Text)
                , wwids : Optional (List Text)
                }
          , flexVolume =
              None
                { driver : Text
                , fsType : Optional Text
                , options : Optional (List { mapKey : Text, mapValue : Text })
                , readOnly : Optional Bool
                , secretRef : Optional { name : Optional Text }
                }
          , flocker =
              None { datasetName : Optional Text, datasetUUID : Optional Text }
          , gcePersistentDisk =
              None
                { fsType : Optional Text
                , partition : Optional Natural
                , pdName : Text
                , readOnly : Optional Bool
                }
          , gitRepo =
              None
                { directory : Optional Text
                , repository : Text
                , revision : Optional Text
                }
          , glusterfs =
              None { endpoints : Text, path : Text, readOnly : Optional Bool }
          , hostPath = None { path : Text, type : Optional Text }
          , iscsi =
              None
                { chapAuthDiscovery : Optional Bool
                , chapAuthSession : Optional Bool
                , fsType : Optional Text
                , initiatorName : Optional Text
                , iqn : Text
                , iscsiInterface : Optional Text
                , lun : Natural
                , portals : Optional (List Text)
                , readOnly : Optional Bool
                , secretRef : Optional { name : Optional Text }
                , targetPortal : Text
                }
          , name = "data"
          , nfs = None { path : Text, readOnly : Optional Bool, server : Text }
          , persistentVolumeClaim = Some
            { claimName = "prometheus", readOnly = None Bool }
          , photonPersistentDisk = None { fsType : Optional Text, pdID : Text }
          , portworxVolume =
              None
                { fsType : Optional Text
                , readOnly : Optional Bool
                , volumeID : Text
                }
          , projected =
              None
                { defaultMode : Optional Natural
                , sources :
                    List
                      { configMap :
                          Optional
                            { items :
                                Optional
                                  ( List
                                      { key : Text
                                      , mode : Optional Natural
                                      , path : Text
                                      }
                                  )
                            , name : Optional Text
                            , optional : Optional Bool
                            }
                      , downwardAPI :
                          Optional
                            { items :
                                Optional
                                  ( List
                                      { fieldRef :
                                          Optional
                                            { apiVersion : Optional Text
                                            , fieldPath : Text
                                            }
                                      , mode : Optional Natural
                                      , path : Text
                                      , resourceFieldRef :
                                          Optional
                                            { containerName : Optional Text
                                            , divisor : Optional Text
                                            , resource : Text
                                            }
                                      }
                                  )
                            }
                      , secret :
                          Optional
                            { items :
                                Optional
                                  ( List
                                      { key : Text
                                      , mode : Optional Natural
                                      , path : Text
                                      }
                                  )
                            , name : Optional Text
                            , optional : Optional Bool
                            }
                      , serviceAccountToken :
                          Optional
                            { audience : Optional Text
                            , expirationSeconds : Optional Natural
                            , path : Text
                            }
                      }
                }
          , quobyte =
              None
                { group : Optional Text
                , readOnly : Optional Bool
                , registry : Text
                , tenant : Optional Text
                , user : Optional Text
                , volume : Text
                }
          , rbd =
              None
                { fsType : Optional Text
                , image : Text
                , keyring : Optional Text
                , monitors : List Text
                , pool : Optional Text
                , readOnly : Optional Bool
                , secretRef : Optional { name : Optional Text }
                , user : Optional Text
                }
          , scaleIO =
              None
                { fsType : Optional Text
                , gateway : Text
                , protectionDomain : Optional Text
                , readOnly : Optional Bool
                , secretRef : { name : Optional Text }
                , sslEnabled : Optional Bool
                , storageMode : Optional Text
                , storagePool : Optional Text
                , system : Text
                , volumeName : Optional Text
                }
          , secret =
              None
                { defaultMode : Optional Natural
                , items :
                    Optional
                      ( List
                          { key : Text, mode : Optional Natural, path : Text }
                      )
                , optional : Optional Bool
                , secretName : Optional Text
                }
          , storageos =
              None
                { fsType : Optional Text
                , readOnly : Optional Bool
                , secretRef : Optional { name : Optional Text }
                , volumeName : Optional Text
                , volumeNamespace : Optional Text
                }
          , vsphereVolume =
              None
                { fsType : Optional Text
                , storagePolicyID : Optional Text
                , storagePolicyName : Optional Text
                , volumePath : Text
                }
          }
        , { awsElasticBlockStore =
              None
                { fsType : Optional Text
                , partition : Optional Natural
                , readOnly : Optional Bool
                , volumeID : Text
                }
          , azureDisk =
              None
                { cachingMode : Optional Text
                , diskName : Text
                , diskURI : Text
                , fsType : Optional Text
                , kind : Text
                , readOnly : Optional Bool
                }
          , azureFile =
              None
                { readOnly : Optional Bool
                , secretName : Text
                , shareName : Text
                }
          , cephfs =
              None
                { monitors : List Text
                , path : Optional Text
                , readOnly : Optional Bool
                , secretFile : Optional Text
                , secretRef : Optional { name : Optional Text }
                , user : Optional Text
                }
          , cinder =
              None
                { fsType : Optional Text
                , readOnly : Optional Bool
                , secretRef : Optional { name : Optional Text }
                , volumeID : Text
                }
          , configMap = Some
            { defaultMode = Some 777
            , items =
                None (List { key : Text, mode : Optional Natural, path : Text })
            , name = Some "prometheus"
            , optional = None Bool
            }
          , csi =
              None
                { driver : Text
                , fsType : Optional Text
                , nodePublishSecretRef : Optional { name : Optional Text }
                , readOnly : Optional Bool
                , volumeAttributes :
                    Optional (List { mapKey : Text, mapValue : Text })
                }
          , downwardAPI =
              None
                { defaultMode : Optional Natural
                , items :
                    Optional
                      ( List
                          { fieldRef :
                              Optional
                                { apiVersion : Optional Text, fieldPath : Text }
                          , mode : Optional Natural
                          , path : Text
                          , resourceFieldRef :
                              Optional
                                { containerName : Optional Text
                                , divisor : Optional Text
                                , resource : Text
                                }
                          }
                      )
                }
          , emptyDir =
              None { medium : Optional Text, sizeLimit : Optional Text }
          , fc =
              None
                { fsType : Optional Text
                , lun : Optional Natural
                , readOnly : Optional Bool
                , targetWWNs : Optional (List Text)
                , wwids : Optional (List Text)
                }
          , flexVolume =
              None
                { driver : Text
                , fsType : Optional Text
                , options : Optional (List { mapKey : Text, mapValue : Text })
                , readOnly : Optional Bool
                , secretRef : Optional { name : Optional Text }
                }
          , flocker =
              None { datasetName : Optional Text, datasetUUID : Optional Text }
          , gcePersistentDisk =
              None
                { fsType : Optional Text
                , partition : Optional Natural
                , pdName : Text
                , readOnly : Optional Bool
                }
          , gitRepo =
              None
                { directory : Optional Text
                , repository : Text
                , revision : Optional Text
                }
          , glusterfs =
              None { endpoints : Text, path : Text, readOnly : Optional Bool }
          , hostPath = None { path : Text, type : Optional Text }
          , iscsi =
              None
                { chapAuthDiscovery : Optional Bool
                , chapAuthSession : Optional Bool
                , fsType : Optional Text
                , initiatorName : Optional Text
                , iqn : Text
                , iscsiInterface : Optional Text
                , lun : Natural
                , portals : Optional (List Text)
                , readOnly : Optional Bool
                , secretRef : Optional { name : Optional Text }
                , targetPortal : Text
                }
          , name = "config"
          , nfs = None { path : Text, readOnly : Optional Bool, server : Text }
          , persistentVolumeClaim =
              None { claimName : Text, readOnly : Optional Bool }
          , photonPersistentDisk = None { fsType : Optional Text, pdID : Text }
          , portworxVolume =
              None
                { fsType : Optional Text
                , readOnly : Optional Bool
                , volumeID : Text
                }
          , projected =
              None
                { defaultMode : Optional Natural
                , sources :
                    List
                      { configMap :
                          Optional
                            { items :
                                Optional
                                  ( List
                                      { key : Text
                                      , mode : Optional Natural
                                      , path : Text
                                      }
                                  )
                            , name : Optional Text
                            , optional : Optional Bool
                            }
                      , downwardAPI :
                          Optional
                            { items :
                                Optional
                                  ( List
                                      { fieldRef :
                                          Optional
                                            { apiVersion : Optional Text
                                            , fieldPath : Text
                                            }
                                      , mode : Optional Natural
                                      , path : Text
                                      , resourceFieldRef :
                                          Optional
                                            { containerName : Optional Text
                                            , divisor : Optional Text
                                            , resource : Text
                                            }
                                      }
                                  )
                            }
                      , secret :
                          Optional
                            { items :
                                Optional
                                  ( List
                                      { key : Text
                                      , mode : Optional Natural
                                      , path : Text
                                      }
                                  )
                            , name : Optional Text
                            , optional : Optional Bool
                            }
                      , serviceAccountToken :
                          Optional
                            { audience : Optional Text
                            , expirationSeconds : Optional Natural
                            , path : Text
                            }
                      }
                }
          , quobyte =
              None
                { group : Optional Text
                , readOnly : Optional Bool
                , registry : Text
                , tenant : Optional Text
                , user : Optional Text
                , volume : Text
                }
          , rbd =
              None
                { fsType : Optional Text
                , image : Text
                , keyring : Optional Text
                , monitors : List Text
                , pool : Optional Text
                , readOnly : Optional Bool
                , secretRef : Optional { name : Optional Text }
                , user : Optional Text
                }
          , scaleIO =
              None
                { fsType : Optional Text
                , gateway : Text
                , protectionDomain : Optional Text
                , readOnly : Optional Bool
                , secretRef : { name : Optional Text }
                , sslEnabled : Optional Bool
                , storageMode : Optional Text
                , storagePool : Optional Text
                , system : Text
                , volumeName : Optional Text
                }
          , secret =
              None
                { defaultMode : Optional Natural
                , items :
                    Optional
                      ( List
                          { key : Text, mode : Optional Natural, path : Text }
                      )
                , optional : Optional Bool
                , secretName : Optional Text
                }
          , storageos =
              None
                { fsType : Optional Text
                , readOnly : Optional Bool
                , secretRef : Optional { name : Optional Text }
                , volumeName : Optional Text
                , volumeNamespace : Optional Text
                }
          , vsphereVolume =
              None
                { fsType : Optional Text
                , storagePolicyID : Optional Text
                , storagePolicyName : Optional Text
                , volumePath : Text
                }
          }
        ]
      }
    }
  }
, status =
    None
      { availableReplicas : Optional Natural
      , collisionCount : Optional Natural
      , conditions :
          Optional
            ( List
                { lastTransitionTime : Optional Text
                , lastUpdateTime : Optional Text
                , message : Optional Text
                , reason : Optional Text
                , status : Text
                , type : Text
                }
            )
      , observedGeneration : Optional Natural
      , readyReplicas : Optional Natural
      , replicas : Optional Natural
      , unavailableReplicas : Optional Natural
      , updatedReplicas : Optional Natural
      }
}

Note that defaultMode of the configMap is now 777 (natural) in the dhall output

configMap = Some
            { defaultMode = Some 777
            , items =
                None (List { key : Text, mode : Optional Natural, path : Text })
            , name = Some "prometheus"
            , optional = None Bool
            }

Converting that dhall back into kubernetes yaml:

> pbpaste | dhall-to-yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  annotations:
    description: Collects metrics and aggregates them into graphs.
  labels:
    deploy: sourcegraph
    sourcegraph-resource-requires: no-cluster-admin
  name: prometheus
spec:
  minReadySeconds: 10
  replicas: 1
  revisionHistoryLimit: 10
  selector:
    matchLabels:
      app: prometheus
  strategy:
    type: Recreate
  template:
    metadata:
      labels:
        app: prometheus
        deploy: sourcegraph
    spec:
      containers:
        - image: "index.docker.io/sourcegraph/prometheus:3.18.0@sha256:e970ed46bdf3f73477f95de9ada424ada4a24505239687ce0e474a62dac6c67b"
          livenessProbe:
            httpGet:
              path: /-/healthy
              port: 9090
            initialDelaySeconds: 30
            timeoutSeconds: 30
          name: prometheus
          ports:
            - containerPort: 9090
              name: http
          readinessProbe:
            httpGet:
              path: /-/ready
              port: 9090
            initialDelaySeconds: 30
            timeoutSeconds: 30
          resources:
            limits:
              cpu: '2'
              memory: "3G"
            requests:
              cpu: "500m"
              memory: "3G"
          terminationMessagePolicy: FallbackToLogsOnError
          volumeMounts:
            - mountPath: /prometheus
              name: data
            - mountPath: /sg_prometheus_add_ons
              name: config
      securityContext:
        runAsUser: 0
      serviceAccountName: prometheus
      volumes:
        - name: data
          persistentVolumeClaim:
            claimName: prometheus
        - configMap:
            defaultMode: 777
            name: prometheus
          name: config

Note that the configMap's defaultMode has changed from 0777 (octal) in the original yaml to 777 (decimal) in the new yaml.

And indeed, trying to apply this yaml into a cluster results in an error

> kubectl apply  -f test.yaml
The Deployment "prometheus" is invalid:
* spec.template.spec.volumes[1].configMap.defaultMode: Invalid value: 777: must be a number between 0 and 0777 (octal), both inclusive

Octal values are an official part of the YAML spec, and it'd be nice if Dhall supported this too (or at least had some sort of visible warning). I am not sure what the fix should be (an official octal number type, yaml-to-dhall converting octal values to the equivalent decimal values, or something else).

[sjakobi]

Octal values are an official part of the YAML spec

That's a reference for YAML 1.1, but yaml-to-dhall's YAML parser (primarily?) tries to comply with YAML 1.2, where octal notation apparently requires a 0o prefix, not just 0.

[ggilmore]

Good to know, but apparently kubectl (or the Kubernetes API server) supports the YAML 1.1 syntax. The official K8s documentation also uses the 0 prefix octal notation: https://kubernetes.io/docs/concepts/configuration/secret/#secret-files-permissions

The nature of these silent transformations also makes it difficult to detect / workaround

[Gabriella439]

Based on the discussion so far it sounds like this can be split into two separate questions:

• Should Dhall have language support for octal literals?

  This is more of a question for the dhall-lang repository, but we can still briefly share our thoughts here

• Should yaml-to-dhall support YAML 1.1 octal literal syntax

  This question is appropriate for this repository

For the former question, I would be fine with standardizing support for octal literals for the language

For the latter question, I think it depends on two things:

• Does kubectl support the newer 0o… octal syntax? (It sounds like it doesn't, but I just want to confirm)

• Does kubectl support non-octal numeric literals for permissions? (Based on a quick Google search it sounds like it does)

In general, adding support for YAML 1.1 octal literals might be problematic for us since the upstream HsYAML package that yaml-to-dhall is based appears to only supports YAML 1.2, which is why I'm exploring workarounds.

[ggilmore]

Does kubectl support the newer 0o… octal syntax? (It sounds like it doesn't, but I just want to confirm)

I think it does (at least from my brief test with the following versions):

> kubectl version 
Client Version: version.Info{Major:"1", Minor:"16+", GitVersion:"v1.16.6-beta.0", GitCommit:"e7f962ba86f4ce7033828210ca3556393c377bcc", GitTreeState:"clean", BuildDate:"2020-01-15T08:26:26Z", GoVersion:"go1.13.5", Compiler:"gc", Platform:"darwin/amd64"}
Server Version: version.Info{Major:"1", Minor:"14+", GitVersion:"v1.14.10-gke.42", GitCommit:"42bef28c2031a74fc68840fce56834ff7ea08518", GitTreeState:"clean", BuildDate:"2020-06-02T16:07:00Z", GoVersion:"go1.12.12b4", Compiler:"gc", Platform:"linux/amd64"}

I don't know if support for this was always there or if this was a recent change (or even if it varies between cloud providers).

Does kubectl support non-octal numeric literals for permissions? (Based on a quick Google search it sounds like it does)

Yes it does (you're able to specify defaultMode: 511 directly and it works as you expect).

I'd still like to encourage support for YAML 1.1 octal literals because that's the only style that I've seen "in the wild" for Kubernetes (probably because that's what's used in the official docs). I'm going to guess that a fair amount of people (maybe most?) use the this style when writing their manifests, so they're likely to be bitten by this when they want to use yaml-to-dhall.

As a data point from the https://github.com/helm/charts repository:

• I found 60+ examples of manifests using the YAML 1.1 octal notation style (0...): https://sourcegraph.com/search?q=repo:%5Egithub%5C.com/helm/charts%24++%28mode%7CdefaultMode%29:+0%5Cd%2B+lang:yaml+++&patternType=regexp

• I couldn't find any examples of manifests using the YAML 1.2 octal notation style (0o...): https://sourcegraph.com/search?q=repo:%5Egithub%5C.com/helm/charts%24++%28mode%7CdefaultMode%29:+0o%5Cd%2B+lang:yaml+++&patternType=regexp

[sjakobi]

• Should Dhall have language support for octal literals?

This question seems only tangentially related to this issue to me?! I wouldn't mind if support for octal literals would be added though.

• Should yaml-to-dhall support YAML 1.1 octal literal syntax

This seems tricky, since IIUC these literals have different meaning in YAML 1.1 vs. 1.2. For example 010 is 8 with YAML 1.1, but 10 with 1.2.

It would be nice if yaml-to-dhall would have a --yaml-1.1 option or something like that, I guess.

Or maybe there's a YAML-1.1 to YAML-1.2 converter that we could recommend for use with yaml-to-dhall?!

[Gabriella439]

@sjakobi: I like the idea of a YAML 1.1 to YAML 1.2 converter

The reason I suggested Dhall support for octal literal syntax was to ensure that the octal literal would be preserved when converting back from Dhall to YAML

[sjakobi]

Or maybe there's a YAML-1.1 to YAML-1.2 converter that we could recommend for use with yaml-to-dhall?!

I have created a SO question about this: https://stackoverflow.com/questions/63472830/how-do-i-convert-yaml-1-1-to-yaml-1-2

While doing so, I remembered that YAML 1.2 is a superset of JSON.

So, to prepare a YAML 1.1 document for consumption by yaml-to-dhall, you can convert it to JSON, for example with this yml2json utility (which, mind you, I have only tested once, not properly vetted). Instead of yaml-to-dhall, you can also use json-to-dhall then.