"lint" command for flipper-pkg tool

Summary:
Implemented json schema for flipper plugin package.json and used it for validation in "flipper-pkg lint" command.

Nice thing about json schema is that it not only allows to validate json, but also can be referenced using "$schema" property in json so IDEs like VSCode can find it and use for code completion, validation and to show properties documentation. I'm going to deploy the schema as a part of documentation website so it can be referenced as https://fbflipper.com/schemas/plugin-package/v2.json.

Also the "$schema" field can be used instead of "specVersion" to determine the specification according to which the plugin is defined. E.g., if specification version 3 would be created, it will be described in schema https://fbflipper.com/schemas/plugin-package/v3.json, etc.

Reviewed By: passy

Differential Revision: D21228294

fbshipit-source-id: f21351e584ef936a7d6b314436448489691f83a6

desktop/pkg/src/utils/runLint.ts

@@ -0,0 +1,96 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @format
+ */
+
+import fs from 'fs-extra';
+import path from 'path';
+import Ajv from 'ajv';
+import filePathExists from './validation/filePathExists';
+
+const pluginPackageJsonSchemaUrl =
+  'https://fbflipper.com/schemas/plugin-package/v2.json';
+
+const packageJsonSchemaUrl =
+  'https://schemastore.azurewebsites.net/schemas/json/package.json';
+
+const schemasDir = path.resolve(__dirname, '..', '..', 'schemas');
+const packageJsonSchemaPath = path.join(schemasDir, 'package.json');
+const pluginPackageJsonSchemaPath = path.join(
+  schemasDir,
+  'plugin-package-v2.json',
+);
+
+export default async function runLint(
+  inputDirectory: string,
+): Promise<null | string[]> {
+  const packageJsonPath = path.join(inputDirectory, 'package.json');
+  if (!(await fs.pathExists(packageJsonPath))) {
+    return [
+      `package.json not found in plugin source directory ${inputDirectory}.`,
+    ];
+  }
+  const packageJsonString = (await fs.readFile(packageJsonPath)).toString();
+  const packageJson = JSON.parse(packageJsonString);
+  if (!packageJson.$schema) {
+    return [
+      [
+        `. should have required property "$schema" pointing to a supported schema URI, e.g.:`,
+        `{`,
+        ` "$schema": "${pluginPackageJsonSchemaUrl}",`,
+        ` "name": "flipper-plugin-example",`,
+        ` ...`,
+        `}`,
+      ].join('\n'),
+    ];
+  }
+
+  if (packageJson.$schema != pluginPackageJsonSchemaUrl) {
+    return [
+      [
+        `.$schema should point to a supported schema. Currently supported schemas:`,
+        `- ${pluginPackageJsonSchemaUrl}`,
+      ].join('\n'),
+    ];
+  }
+
+  const packageJsonSchema = await fs.readJson(packageJsonSchemaPath);
+  const pluginPackageJsonSchema = await fs.readJson(
+    pluginPackageJsonSchemaPath,
+  );
+  const ajv = new Ajv({
+    allErrors: true,
+    loadSchema,
+    schemaId: 'auto',
+    meta: true,
+    jsonPointers: true,
+  });
+  require('ajv-errors')(ajv);
+  ajv
+    .addMetaSchema(require('ajv/lib/refs/json-schema-draft-04.json'))
+    .addSchema(packageJsonSchema, packageJsonSchemaUrl)
+    .addSchema(pluginPackageJsonSchema, pluginPackageJsonSchemaUrl)
+    .addKeyword('filePathExists', filePathExists(inputDirectory));
+
+  const validate = await ajv.compileAsync(pluginPackageJsonSchema);
+  const valid = await validate(packageJson);
+  if (!valid) {
+    return validate.errors
+      ? validate.errors.map(
+          (error) =>
+            `${error.dataPath === '' ? '.' : error.dataPath} ${
+              error.message || 'unspecified error'
+            }`,
+        )
+      : [];
+  }
+  return null;
+}
+
+async function loadSchema(_uri: string) {
+  return false;
+}

desktop/pkg/src/utils/validation/filePathExists.ts

@@ -0,0 +1,43 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @format
+ */
+
+import ajv from 'ajv';
+import path from 'path';
+import fs from 'fs-extra';
+
+export default function (inputDirectory: string) {
+  const filePathExists: ajv.KeywordDefinition = {
+    errors: true,
+    compile: function validatePathExists(schema: any) {
+      function filePathExistsValidator(value: any, dataPath: any) {
+        const it = filePathExistsValidator as ajv.SchemaValidateFunction;
+        if (!schema) {
+          return true;
+        }
+        it.errors = [];
+        const tpl = {
+          keyword: 'filePathExists',
+          dataPath,
+          schemaPath: '',
+          params: [],
+        };
+        const fullPath = path.resolve(inputDirectory, value);
+        if (!fs.pathExistsSync(fullPath) || !fs.lstatSync(fullPath).isFile()) {
+          it.errors.push({
+            ...tpl,
+            message: `should point to a valid file`,
+          });
+        }
+        return it.errors.length === 0;
+      }
+      return filePathExistsValidator;
+    },
+  };
+  return filePathExists;
+}