feat: add payload validation against asyncapi schema format (#104)

Co-authored-by: Fran Méndez <[email protected]>

README.md

@@ -86,7 +86,15 @@ AsyncAPI doesn't enforce one schema format for messages. You can have payload of
 1. Create custom parser module that exports two functions:
     ```js
     module.exports = {
-      parse: ({ message, defaultSchemaFormat }) => { //custom parsing logic},
+      /*
+       * message {Object} is the object containing AsyncAPI Message property
+       * defaultSchemaFormat {String} information about the default schema format mime type
+       * schemaFormat {String} information about custom schemaFormat mime type provided in AsyncAPI Document
+       * fileFormat {String} information if provided AsyncAPI Document was JSON or YAML
+       * parsedAsyncAPIDocument {Object} Full AsyncAPI Document parsed into Object
+       * pathToPayload {String} path of the message passed to the parser, relative to the root of AsyncAPI Document
+      */
+      parse: ({ message, defaultSchemaFormat, originalAsyncAPIDocument, schemaFormat, fileFormat, parsedAsyncAPIDocument, pathToPayload }) => { /* custom parsing logic */ },
       getMimeTypes: () => [
         '//mime types that will be used as the `schemaFormat` property of the message to specify its mime type',
         'application/vnd.custom.type;version=1.0.0',
@@ -118,6 +126,7 @@ This package throws a bunch of different error types. All errors contain a `type
 |`unexpected-error`|`parsedJSON`|We have our code covered with try/catch blocks and you should never see this error. If you see it, please open an issue to let us know.
 |`validation-errors`|`parsedJSON`, `validationErrors`|The AsyncAPI document contains errors. See `validationErrors` for more information.
 |`impossible-to-register-parser`| None | Registration of custom message parser failed.
+|`schema-validation-errors`| `parsedJSON`, `validationErrors` | Schema of the payload provided in the AsyncAPI document is not valid with AsyncAPI schema format.
 
 For more information about the `ParserError` class, [check out the documentation](./API.md#new_ParserError_new).
 

lib/asyncapiSchemaFormatParser.js

@@ -0,0 +1,71 @@
+const Ajv = require('ajv');
+const ParserError = require('./errors/parser-error');
+const asyncapi = require('@asyncapi/specs');
+const { improveAjvErrors } = require('./utils');
+
+module.exports = {
+  parse,
+  getMimeTypes
+};
+
+async function parse({ message, originalAsyncAPIDocument, fileFormat, parsedAsyncAPIDocument, pathToPayload }) {
+  const ajv = new Ajv({
+    jsonPointers: true,
+    allErrors: true,
+    schemaId: 'id',
+    logger: false,
+  });
+  const payloadSchema = preparePayloadSchema(asyncapi[parsedAsyncAPIDocument.asyncapi]);
+  const validate = ajv.compile(payloadSchema);
+  const valid = validate(message.payload);
+
+  if (!valid) throw new ParserError({
+    type: 'schema-validation-errors',
+    title: 'This is not a valid AsyncAPI Schema Object.',
+    parsedJSON: parsedAsyncAPIDocument,
+    validationErrors: improveAjvErrors(addFullPathToDataPath(validate.errors, pathToPayload), originalAsyncAPIDocument, fileFormat),
+  });
+}
+
+function getMimeTypes() {
+  return [
+    'application/vnd.aai.asyncapi;version=2.0.0',
+    'application/vnd.aai.asyncapi+json;version=2.0.0',
+    'application/vnd.aai.asyncapi+yaml;version=2.0.0',
+    'application/schema;version=draft-07',
+    'application/schema+json;version=draft-07',
+    'application/schema+yaml;version=draft-07',
+  ];
+}
+
+/**
+ * To validate schema of the payload we just need a small portion of official AsyncAPI spec JSON Schema, the definition of the schema must be
+ * a main part of the JSON Schema
+ * 
+ * @param  {Object} asyncapiSchema AsyncAPI specification JSON Schema
+ * @returns {Object} valid JSON Schema document describing format of AsyncAPI-valid schema for message payload
+ */
+function preparePayloadSchema(asyncapiSchema) {
+  return {
+    $ref: '#/definitions/schema',
+    definitions: asyncapiSchema.definitions
+  };
+}
+
+/**
+ * Errors from Ajv contain dataPath information about parameter relative to parsed payload message. 
+ * This function enriches dataPath with additional information on where is the parameter located in AsyncAPI document
+ * 
+ * @param  {Array<Object>} errors Ajv errors
+ * @param  {String} path Path to location of the payload schema in AsyncAPI Document
+ * @returns {Array<Object>} same object as received in input but with modified datePath property so it contain full path relative to AsyncAPI document
+ */
+function addFullPathToDataPath(errors, path) {
+  return errors.map((err) => ({
+    ...err,
+    ...{
+      dataPath: `${path}${err.dataPath}`
+    }
+  }));
+}
+

lib/index.js

@@ -1,17 +1,6 @@
 const parser = require('./parser');
+const defaultAsyncAPISchemaParser = require('./asyncapiSchemaFormatParser');
 
-const noop = {
-  parse: () => {}, // No operation
-  getMimeTypes: () => [
-    'application/vnd.aai.asyncapi;version=2.0.0',
-    'application/vnd.aai.asyncapi+json;version=2.0.0',
-    'application/vnd.aai.asyncapi+yaml;version=2.0.0',
-    'application/schema;version=draft-07',
-    'application/schema+json;version=draft-07',
-    'application/schema+yaml;version=draft-07',
-  ]
-};
-
-parser.registerSchemaParser(noop);
+parser.registerSchemaParser(defaultAsyncAPISchemaParser);
 
 module.exports = parser;

lib/parser.js

@@ -160,26 +160,31 @@ async function customDocumentOperations(js, asyncapiYAMLorJSON, initialFormat, o
       const op = channel[opName];
       if (op) {
         const messages = op.message ? (op.message.oneOf || [op.message]) : [];
+        const pathToPayload = `/channels/${ channelName }/${ opName }/message/payload`; 
         if (options.applyTraits) {  
           applyTraits(op);
           messages.forEach(m => applyTraits(m));
         }
         for (const m of messages) {
-          await validateAndConvertMessage(m);
+          await validateAndConvertMessage(m, asyncapiYAMLorJSON, initialFormat, js, pathToPayload);
         }
       }
     });
     await Promise.all(convert);
   }
 }
 
-async function validateAndConvertMessage(msg) {
+async function validateAndConvertMessage(msg, originalAsyncAPIDocument, fileFormat, parsedAsyncAPIDocument, pathToPayload) {
   const schemaFormat = msg.schemaFormat || DEFAULT_SCHEMA_FORMAT;
 
   await PARSERS[schemaFormat]({
     schemaFormat,
     message: msg,
     defaultSchemaFormat: DEFAULT_SCHEMA_FORMAT,
+    originalAsyncAPIDocument,
+    parsedAsyncAPIDocument,
+    fileFormat, 
+    pathToPayload
   });
 
   msg.schemaFormat = DEFAULT_SCHEMA_FORMAT;

test/asyncapiSchemaFormatParser_test.js

@@ -0,0 +1,80 @@
+const parser = require('../lib');
+const chai = require('chai');
+const fs = require('fs');
+const path = require('path');
+const expect = chai.expect;
+
+describe('asyncapiSchemaFormatParser', function() {
+  it('should throw an error because of invalid schema', async function() {
+    const invalidAsyncapi = fs.readFileSync(path.resolve(__dirname, './wrong/invalid-payload-asyncapi-format.json'), 'utf8');
+    try {
+      await parser.parse(invalidAsyncapi);
+    } catch (e) {
+      expect(e.type).to.equal('https://github.com/asyncapi/parser-js/schema-validation-errors');
+      expect(e.title).to.equal('This is not a valid AsyncAPI Schema Object.');
+      expect(e.parsedJSON).to.deep.equal(JSON.parse(invalidAsyncapi));
+      expect(e.validationErrors).to.deep.equal([
+        {
+          title: '/channels/mychannel/publish/message/payload/additionalProperties should be object,boolean',
+          location: {
+            jsonPointer: '/channels/mychannel/publish/message/payload/additionalProperties',
+            startLine: 13,
+            startColumn: 38,
+            startOffset: 252,
+            endLine: 15,
+            endColumn: 15,
+            endOffset: 297
+          }
+        },
+        {
+          title: '/channels/mychannel/publish/message/payload/additionalProperties should be object,boolean',
+          location: {
+            jsonPointer: '/channels/mychannel/publish/message/payload/additionalProperties',
+            startLine: 13,
+            startColumn: 38,
+            startOffset: 252,
+            endLine: 15,
+            endColumn: 15,
+            endOffset: 297
+          }
+        },
+        {
+          title: '/channels/mychannel/publish/message/payload/additionalProperties should be object',
+          location: {
+            jsonPointer: '/channels/mychannel/publish/message/payload/additionalProperties',
+            startLine: 13,
+            startColumn: 38,
+            startOffset: 252,
+            endLine: 15,
+            endColumn: 15,
+            endOffset: 297
+          }
+        },
+        {
+          title: '/channels/mychannel/publish/message/payload/additionalProperties should be boolean',
+          location: {
+            jsonPointer: '/channels/mychannel/publish/message/payload/additionalProperties',
+            startLine: 13,
+            startColumn: 38,
+            startOffset: 252,
+            endLine: 15,
+            endColumn: 15,
+            endOffset: 297
+          }
+        },
+        {
+          title: '/channels/mychannel/publish/message/payload/additionalProperties should match some schema in anyOf',
+          location: {
+            jsonPointer: '/channels/mychannel/publish/message/payload/additionalProperties',
+            startLine: 13,
+            startColumn: 38,
+            startOffset: 252,
+            endLine: 15,
+            endColumn: 15,
+            endOffset: 297
+          }
+        }
+      ]);
+    }
+  });
+});

test/wrong/invalid-payload-asyncapi-format.json

@@ -0,0 +1,21 @@
+{
+  "asyncapi": "2.0.0",
+  "info": {
+    "title": "My API",
+    "version": "1.0.0"
+  },
+  "channels": {
+    "mychannel": {
+      "publish": {
+        "message": {
+          "payload": {
+            "type": "object",
+            "additionalProperties": [
+              "invalid_array"
+            ]
+          }
+        }
+      }
+    }
+  }
+}