feat: initial app and instructions

.github/workflows/ci.yaml

@@ -0,0 +1,66 @@
+name: Docker
+
+on:
+  push:
+    branches: [ "main" ]
+    paths-ignore:
+    - README.md
+    - score.yaml
+
+env:
+  # Use docker.io for Docker Hub if empty
+  REGISTRY: ghcr.io
+  # github.repository as <account>/<repo>
+  IMAGE_NAME: ${{ github.repository }}
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v3
+
+      # Set up BuildKit Docker container builder to be able to build
+      # multi-platform images and export cache
+      # https://github.com/docker/setup-buildx-action
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@f95db51fddba0c2d1ec667646a06c2ce06100226 # v3.0.0
+
+      # Login against a Docker registry except on PR
+      # https://github.com/docker/login-action
+      - name: Log into registry ${{ env.REGISTRY }}
+        uses: docker/login-action@343f7c4344506bcbf9b4de18042ae17996df046d # v3.0.0
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      # Extract metadata (tags, labels) for Docker
+      # https://github.com/docker/metadata-action
+      - name: Extract Docker metadata
+        id: meta
+        uses: docker/metadata-action@96383f45573cb7f253c731d3b3ab81c87ef81934 # v5.0.0
+        with:
+          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+          tags: |
+            type=ref,event=branch
+            type=sha
+
+      # Build and push Docker image with Buildx (don't push on PR)
+      # https://github.com/docker/build-push-action
+      - name: Build and push Docker image
+        id: build-and-push
+        uses: docker/build-push-action@0565240e2d4ab88bba5387d719585280857ece09 # v5.0.0
+        with:
+          context: .
+          platforms: linux/amd64,linux/arm64
+          push: true
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+          cache-from: type=gha
+          cache-to: type=gha,mode=max

.gitignore

@@ -19,3 +19,9 @@
 
 # Go workspace file
 go.work
+
+# Score
+.score-compose/
+compose.yaml
+.score-k8s/
+manifests.yaml

Dockerfile

@@ -0,0 +1,15 @@
+FROM golang:1.22-alpine AS builder
+
+WORKDIR /app
+ENV CGO_ENABLED=0 GOOS=linux GOARCH=amd64 GOWORK=off
+COPY go.mod go.sum ./
+RUN --mount=type=cache,target=/go/pkg/mod \
+    go mod download
+RUN --mount=target=. \
+    --mount=type=cache,target=/go/pkg/mod \
+    --mount=type=cache,target=/root/.cache/go-build \
+    go build -o /sample .
+
+FROM gcr.io/distroless/static as final
+COPY --from=builder /sample .
+ENTRYPOINT ["/sample"]

README.md

@@ -1,2 +1,43 @@
 # sample-app-gif
-The sample app used for the gif and video embedded in the docs
+
+The sample app used for the gif and video embedded in the docs. The purpose is for it to be complex enough to show the core value propositions of Score:
+
+- Convert to more than one deployment format
+- Provision ingress and database resources with dynamic credentials
+- Launch locally or remotely
+- Show evidence that the request was routed correctly and hit the target database
+
+All with as few lines of code as possible. We're going to for simple and short rather than _correct_.
+
+## How to record the sample gif
+
+Use <https://docs.asciinema.org/>.
+
+Preparation:
+
+```
+$ rm -rfv .score-compose .score-k8s compose.yaml manifests.yaml
+$ docker pull ghcr.io/score-spec/sample-app-gif:main
+
+$ kind create cluster
+$ kubectl use-context kind-kind
+$ kubectl --context kind-kind apply -f https://github.com/kubernetes-sigs/gateway-api/releases/download/v1.0.0/standard-install.yam
+$ helm --kube-context kind-kind install ngf oci://ghcr.io/nginxinc/charts/nginx-gateway-fabric --create-namespace -n nginx-gateway --set service.type=ClusterIP
+```
+
+Instructions to record:
+
+```
+$ score-compose init
+$ score-compose generate score.yaml
+$ docker compose up -d 
+$ curl http://$(score-compose resources get-outputs 'dns.default#sample.dns' --format '{{ .host }}'):8080/ -i
+$ docker logs sample-app-gif-sample-main-1
+$ docker compose down -v
+
+$ score-k8s init
+$ score-k8s generate score.yaml
+$ kubectl apply -f manifests.yaml
+$ kubectl wait deployments/sample --for=condition=Ready
+$ curl http://$(score-compose resources get-outputs 'dns.default#sample.dns' --format '{{ .host }}')
+```

go.mod

@@ -0,0 +1,5 @@
+module github.com/score-spec/sample-app-gif
+
+go 1.22.0
+
+require github.com/lib/pq v1.10.9

go.sum

@@ -0,0 +1,2 @@
+github.com/lib/pq v1.10.9 h1:YXG7RB+JIjhP29X+OtkiDnYaXQwpS4JEWq7dtCCRUEw=
+github.com/lib/pq v1.10.9/go.mod h1:AlVN5x4E4T544tWzH6hKfbfQvm3HdbOxrmggDNAPY9o=

main.go

@@ -0,0 +1,50 @@
+package main
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+	"log"
+	"net/http"
+	"os"
+
+	_ "github.com/lib/pq"
+)
+
+const sqlConnectionStringVar = "PG_CONNECTION_STRING"
+const listenAddress = ":8080"
+
+func main() {
+	// First, get the connection string and attempt a connection or fail
+	connStr := os.Getenv(sqlConnectionStringVar)
+	conn, err := sql.Open("postgres", connStr)
+	if err != nil {
+		log.Fatalf("failed to open the database %s=%s: %v", sqlConnectionStringVar, connStr, err)
+	}
+	defer conn.Close()
+
+	// Second, wait until we get a successful connection to the db
+	if err := conn.PingContext(context.TODO()); err != nil {
+		log.Fatalf("failed to connect to database %s=%s: %v", sqlConnectionStringVar, connStr, err)
+	}
+	log.Printf("successfully connected to database %s=%s", sqlConnectionStringVar, connStr)
+
+	// Third, link the handler function
+	http.HandleFunc("GET /{$}", func(writer http.ResponseWriter, request *http.Request) {
+		var versionOutput string
+		if err := conn.QueryRowContext(request.Context(), "SELECT version()").Scan(&versionOutput); err != nil {
+			writer.WriteHeader(http.StatusInternalServerError)
+			_, _ = fmt.Fprintf(writer, "Failed to get sql version: %v", err)
+			log.Printf("%s %s %s status=500: %v", request.Host, request.Method, request.RequestURI, err)
+		} else {
+			_, _ = fmt.Fprintf(writer, "SQL VERSION: %s", versionOutput)
+			log.Printf("%s %s %s status=200", request.Host, request.Method, request.RequestURI)
+		}
+	})
+
+	// Finally, run the http server
+	log.Print("starting server")
+	if err := http.ListenAndServe(listenAddress, http.DefaultServeMux); err != nil {
+		log.Fatal(err.Error())
+	}
+}

score.yaml

@@ -0,0 +1,26 @@
+apiVersion: score.dev/v1b1
+metadata:
+  name: sample
+
+containers:
+  main:
+    image: ghcr.io/score-spec/sample-app-gif:main
+    variables:
+      PG_CONNECTION_STRING: "postgresql://${resources.db.username}:${resources.db.password}@${resources.db.host}:${resources.db.port}/${resources.db.database}?sslmode=disable"
+
+service:
+  ports:
+    web:
+      port: 8080
+
+resources:
+  db:
+    type: postgres
+  dns:
+    type: dns
+  route:
+    type: route
+    params:
+      host: ${resources.dns.host}
+      path: /
+      port: 8080