Refactor API Schema and validation

- /schema now returns full openapi/swagger schema
- That schema is used to validate incoming requests
- And used as a contract in future integration tests
- Moved route files up one level
- Fixed incorrect 404 reponses when getting objects
- Fixed saving new objects and passing jsonschemavalidation

backend/schema/index.js

@@ -0,0 +1,41 @@
+const refParser = require('@apidevtools/json-schema-ref-parser');
+
+let compiledSchema = null;
+
+module.exports = {
+
+	/**
+	 * Compiles the schema, by dereferencing it, only once
+	 * and returns the memory cached value
+	 */
+	getCompiledSchema: async () => {
+		if (compiledSchema === null) {
+			compiledSchema = await refParser.dereference(__dirname + '/swagger.json', {
+				mutateInputSchema: false,
+			});
+		}
+		return compiledSchema;
+	},
+
+	/**
+	 * Scans the schema for the validation schema for the given path and method
+	 * and returns it.
+	 *
+	 * @param {string} path
+	 * @param {string} method
+	 * @returns string|null
+	 */
+	getValidationSchema: (path, method) => {
+		if (compiledSchema !== null &&
+			typeof compiledSchema.paths[path] !== 'undefined' &&
+			typeof compiledSchema.paths[path][method] !== 'undefined' &&
+			typeof compiledSchema.paths[path][method].requestBody !== 'undefined' &&
+			typeof compiledSchema.paths[path][method].requestBody.content !== 'undefined' &&
+			typeof compiledSchema.paths[path][method].requestBody.content['application/json'] !== 'undefined' &&
+			typeof compiledSchema.paths[path][method].requestBody.content['application/json'].schema !== 'undefined'
+		) {
+			return compiledSchema.paths[path][method].requestBody.content['application/json'].schema;
+		}
+		return null;
+	}
+};