perform simple handling for unknown YAML tags

Author: mansurpasha

package.json

@@ -9,7 +9,7 @@
     "blessed-contrib": "^4.8.17",
     "chalk": "^4.0.0",
     "commander": "^7.1.0",
-    "js-yaml": "^3.13.1",
+    "js-yaml": "^4.0.0",
     "moment": "^2.24.0",
     "node-emoji": "^1.10.0",
     "open": "^8.0.2",
@@ -21,6 +21,7 @@
     "@babel/core": "^7.5.5",
     "@babel/preset-env": "^7.5.5",
     "@types/jest": "^26.0.20",
+    "@types/js-yaml": "^4.0.0",
     "babel-jest": "^26.6.3",
     "eslint": "^7.21.0",
     "eslint-config-airbnb-base": "^14.0.0",

__test__/util/serverlessConfigParser.test.js src/services/severlessConfigParser/__test__/serverlessConfigParser.test.js

@@ -4,8 +4,8 @@ import {
   transformArgsToDict,
   replaceStacknameOpt,
   CYAN_STRING_FORMAT,
-} from "../../src/services/severlessConfigParser/helpers";
-import ServerlessConfigParser from "../../src/services/severlessConfigParser/serverlessConfigParser";
+} from "../helpers";
+import ServerlessConfigParser from "../serverlessConfigParser";
 
 const TEST_YAML_FILE_EMPTY = "";
 const TEST_YAML_FILE = `
@@ -42,6 +42,30 @@ provider:
   stage: \${opt:stage, 'dev'}
 `;
 
+const TEST_YAML_FILE_REF = `
+service:
+  name: test-\${opt:testArg1}
+
+provider:
+  name: aws
+  runtime: nodejs10.x
+  region: eu-west-1
+  stage: \${opt:stage, 'dev'}
+
+functions:
+  hello:
+    handler: hello.main
+    memorySize: 1024
+    timeout: 6
+    events:
+      - http:
+          method: get
+          path: hello
+          authorizer:
+            type: COGNITO_USER_POOLS
+            authorizerId: !Ref ApiGatewayAuthorizer
+`;
+
 // eslint-disable-next-line no-template-curly-in-string
 const STACK_NAME_OPT = "test-${opt:testArg1}";
 // eslint-disable-next-line no-template-curly-in-string
@@ -161,4 +185,11 @@ describe("Serverless Config Parsing", () => {
     const stage = "test";
     expect(SLS.getStackName(stage)).toBe("test-backend-test");
   });
+
+  it("should continue as normal when the config contains AWS intrinsic function tags", () => {
+    const SLS = setupConfigParser(TEST_YAML_FILE_REF);
+    expect(SLS.getStage()).toBe("dev");
+    expect(SLS.getStackName("dev")).toBe("test-backend-dev");
+    expect(SLS.getRegion()).toBe("eu-west-1");
+  });
 });

src/services/severlessConfigParser/serverlessConfigParser.js

@@ -1,9 +1,14 @@
+import YAML_SCHEMA from "./ymlParsingSchema";
 import { transformArgsToDict, replaceStacknameOpt } from "./helpers";
 
 const fs = require("fs");
 const path = require("path");
 const YAML = require("js-yaml");
 
+function parseYaml(yamlString) {
+  return YAML.load(yamlString, { schema: YAML_SCHEMA });
+}
+
 class ServerlessConfigParser {
   constructor(program) {
     const { args, location } = program;
@@ -13,9 +18,9 @@ class ServerlessConfigParser {
     const jsonPath = path.join(location, "serverless.json");
 
     if (fs.existsSync(ymlPath)) {
-      this.config = YAML.load(fs.readFileSync(ymlPath).toString("utf8"));
+      this.config = parseYaml(fs.readFileSync(ymlPath, { encoding: "utf-8" }));
     } else if (fs.existsSync(yamlPath)) {
-      this.config = YAML.load(fs.readFileSync(yamlPath).toString("utf8"));
+      this.config = parseYaml(fs.readFileSync(yamlPath, { encoding: "utf-8" }));
     } else if (fs.existsSync(jsonPath)) {
       this.config = JSON.parse(fs.readFileSync(jsonPath).toString("utf8"));
     }

src/services/severlessConfigParser/ymlParsingSchema.js

@@ -0,0 +1,31 @@
+const yaml = require("js-yaml");
+
+class CustomTag {
+  constructor(type, data) {
+    this.type = type;
+    this.data = data;
+  }
+}
+
+const tags = ["scalar", "sequence", "mapping"].map(
+  (kind) =>
+    // first argument here is a prefix, so this type will handle anything starting with !
+    new yaml.Type("!", {
+      kind,
+      multi: true,
+      representName(object) {
+        return object.type;
+      },
+      represent(object) {
+        return object.data;
+      },
+      instanceOf: CustomTag,
+      construct(data, type) {
+        return new CustomTag(type, data);
+      },
+    })
+);
+
+const YAML_SCHEMA = yaml.DEFAULT_SCHEMA.extend(tags);
+
+export default YAML_SCHEMA;

yarn.lock

@@ -1342,6 +1342,11 @@
     jest-diff "^26.0.0"
     pretty-format "^26.0.0"
 
+"@types/js-yaml@^4.0.0":
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/@types/js-yaml/-/js-yaml-4.0.0.tgz#d1a11688112091f2c711674df3a65ea2f47b5dfb"
+  integrity sha512-4vlpCM5KPCL5CfGmTbpjwVKbISRYhduEJvvUWsH5EB7QInhEj94XPZ3ts/9FPiLZFqYO0xoW4ZL8z2AabTGgJA==
+
 "@types/json-schema@^7.0.3":
   version "7.0.7"
   resolved "https://registry.yarnpkg.com/@types/json-schema/-/json-schema-7.0.7.tgz#98a993516c859eb0d5c4c8f098317a9ea68db9ad"
@@ -1590,6 +1595,11 @@ argparse@^1.0.7:
   dependencies:
     sprintf-js "~1.0.2"
 
+argparse@^2.0.1:
+  version "2.0.1"
+  resolved "https://registry.yarnpkg.com/argparse/-/argparse-2.0.1.tgz#246f50f3ca78a3240f6c997e8a9bd1eac49e4b38"
+  integrity sha512-8+9WqebbFzpX9OR+Wa6O29asIogeRMzcGtAINdpMHHyAg10f05aSFVBbcEqGf/PXw1EjAZ+q2/bEBg3DvurK3Q==
+
 arr-diff@^4.0.0:
   version "4.0.0"
   resolved "https://registry.yarnpkg.com/arr-diff/-/arr-diff-4.0.0.tgz#d6461074febfec71e7e15235761a329a5dc7c520"
@@ -4390,6 +4400,13 @@ js-yaml@^3.13.1:
     argparse "^1.0.7"
     esprima "^4.0.0"
 
+js-yaml@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/js-yaml/-/js-yaml-4.0.0.tgz#f426bc0ff4b4051926cd588c71113183409a121f"
+  integrity sha512-pqon0s+4ScYUvX30wxQi3PogGFAlUyH0awepWvwkj4jD4v+ova3RiYw8bmA6x2rDrEaj8i/oWKoRxpVNW+Re8Q==
+  dependencies:
+    argparse "^2.0.1"
+
 jsbn@~0.1.0:
   version "0.1.1"
   resolved "https://registry.yarnpkg.com/jsbn/-/jsbn-0.1.1.tgz#a5e654c2e5a2deb5f201d96cefbca80c0ef2f513"