feat: add support for async fetching inside config (#823)

* read config file async

* fix test

* update test

* added tests

* fix tests and code

* update type

* Update src/common_types.ts

---------

Co-authored-by: vigneshshanmugam <[email protected]>

Author: shahzad31

__tests__/config.test.ts

@@ -33,15 +33,15 @@ const FIXTURES_DIR = join(__dirname, 'fixtures');
 describe('Config', () => {
   it('read config based on environment', async () => {
     const configPath = join(FIXTURES_DIR, 'synthetics.config.ts');
-    expect(readConfig('development', configPath)).toMatchObject({
+    expect(await readConfig('development', configPath)).toMatchObject({
       params: {
         url: 'dev',
       },
       playwrightOptions: {
         ...devices['Galaxy S9+'],
       },
     });
-    expect(readConfig('testing', configPath)).toMatchObject({
+    expect(await readConfig('testing', configPath)).toMatchObject({
       params: {
         url: 'non-dev',
       },
@@ -50,15 +50,35 @@ describe('Config', () => {
 
   it('throw error when config does not exist', async () => {
     const tempPath = generateTempPath();
-    function getConfig() {
-      readConfig('development', tempPath);
-    }
-    expect(getConfig).toThrowError(
+    expect(readConfig('development', tempPath)).rejects.toThrow(
       new Error('Synthetics config file does not exist: ' + tempPath)
     );
   });
 
   it('recursively look for configs and exit', async () => {
-    expect(readConfig('development')).toEqual({});
+    expect(await readConfig('development')).toEqual({});
+  });
+
+  describe('read config async', () => {
+    it('merge async config', async () => {
+      const configPath = join(FIXTURES_DIR, 'async-params.config.ts');
+      expect(await readConfig('development', configPath)).toMatchObject({
+        params: {
+          url: 'dev',
+        },
+      });
+      expect(await readConfig('testing', configPath)).toMatchObject({
+        params: {
+          url: 'non-dev',
+        },
+      });
+    });
+
+    it('catch errors on async config', async () => {
+      const configPath = join(FIXTURES_DIR, 'async-params-err.config.ts');
+      expect(readConfig('development', configPath)).rejects.toThrow(
+        'failed to fetch params'
+      );
+    });
   });
 });

__tests__/fixtures/async-params-err.config.ts

@@ -0,0 +1,43 @@
+/**
+ * MIT License
+ *
+ * Copyright (c) 2020-present, Elastic NV
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ */
+
+import type { SyntheticsConfig } from '../../src';
+
+const getParams = async () => {
+  // return delayed error promise to simulate async
+  return new Promise<Record<string, string>>((_, reject) => {
+    reject(new Error('failed to fetch params'));
+  });
+};
+
+module.exports = async env => {
+  const config: SyntheticsConfig = {
+    params: await getParams(),
+  };
+  if (env !== 'development' && config.params) {
+    config.params.url = 'non-dev';
+  }
+  return config;
+};

__tests__/fixtures/async-params.config.ts

@@ -0,0 +1,43 @@
+/**
+ * MIT License
+ *
+ * Copyright (c) 2020-present, Elastic NV
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ */
+
+import type { SyntheticsConfig } from '../../src';
+
+const getParams = async () => {
+  // resolve with delayed promise to simulate async
+  return new Promise<Record<string, string>>(resolve => {
+    setTimeout(() => resolve({ url: 'dev' }));
+  });
+};
+
+export default async env => {
+  const config: SyntheticsConfig = {
+    params: await getParams(),
+  };
+  if (env !== 'development' && config.params) {
+    config.params.url = 'non-dev';
+  }
+  return config;
+};

__tests__/options.test.ts

@@ -28,7 +28,7 @@ import { normalizeOptions } from '../src/options';
 import { join } from 'path';
 
 describe('options', () => {
-  it('normalize', () => {
+  it('normalize', async () => {
     const cliArgs: CliArgs = {
       params: {
         foo: 'bar',
@@ -43,12 +43,12 @@ describe('options', () => {
       pauseOnError: true,
       config: join(__dirname, 'fixtures', 'synthetics.config.ts'),
     };
-    expect(normalizeOptions({})).toMatchObject({
+    expect(await normalizeOptions({})).toMatchObject({
       environment: 'test',
       params: {},
       screenshots: 'on',
     });
-    expect(normalizeOptions(cliArgs)).toMatchObject({
+    expect(await normalizeOptions(cliArgs)).toMatchObject({
       dryRun: true,
       environment: 'test',
       match: 'check*',
@@ -76,9 +76,9 @@ describe('options', () => {
     });
   });
 
-  it('normalize monitor configs', () => {
+  it('normalize monitor configs', async () => {
     const config = join(__dirname, 'fixtures', 'synthetics.config.ts');
-    expect(normalizeOptions({ config }, 'push')).toMatchObject({
+    expect(await normalizeOptions({ config }, 'push')).toMatchObject({
       screenshots: 'off',
       schedule: 10,
       privateLocations: ['test-location'],
@@ -94,7 +94,7 @@ describe('options', () => {
     });
 
     expect(
-      normalizeOptions(
+      await normalizeOptions(
         {
           config,
           schedule: 3,
@@ -120,14 +120,14 @@ describe('options', () => {
     });
   });
 
-  it('cli arg headless override playwright headless arg', () => {
+  it('cli arg headless override playwright headless arg', async () => {
     const cliArgs: CliArgs = {
       playwrightOptions: {
         headless: false,
       },
       headless: true,
     };
-    expect(normalizeOptions(cliArgs)).toMatchObject({
+    expect(await normalizeOptions(cliArgs)).toMatchObject({
       playwrightOptions: {
         headless: true,
       },

src/cli.ts

@@ -134,7 +134,7 @@ program
   .action(async (cliArgs: CliArgs) => {
     const tearDown = await globalSetup(cliArgs, program.args);
     try {
-      const options = normalizeOptions(cliArgs, 'run');
+      const options = await normalizeOptions(cliArgs, 'run');
       const results = await run(options);
       /**
        * Exit with error status if any journey fails
@@ -196,14 +196,14 @@ program
     ]);
     try {
       const settings = await loadSettings();
-      const options = normalizeOptions(
+      const options = (await normalizeOptions(
         {
           ...program.opts(),
           ...settings,
           ...cmdOpts,
         },
         'push'
-      ) as PushOptions;
+      )) as PushOptions;
       await validatePush(options, settings);
       const monitors = runner.buildMonitors(options);
       if ((options as CliArgs).throttling == null) {

src/config.ts

@@ -27,7 +27,10 @@ import { isAbsolute, resolve, dirname } from 'path';
 import { SyntheticsConfig } from './common_types';
 import { isFile } from './helpers';
 
-export function readConfig(env: string, config?: string): SyntheticsConfig {
+export async function readConfig(
+  env: string,
+  config?: string
+): Promise<SyntheticsConfig> {
   let options = {};
   const cwd = process.cwd();
   /**
@@ -47,6 +50,14 @@ export function readConfig(env: string, config?: string): SyntheticsConfig {
   }
   if (typeof options === 'function') {
     options = options(env);
+    const optionsPromise = options as Promise<SyntheticsConfig>;
+    if (
+      optionsPromise != null &&
+      typeof optionsPromise.then === 'function' &&
+      typeof optionsPromise.catch === 'function'
+    ) {
+      options = await optionsPromise;
+    }
   }
   return options;
 }

src/options.ts

@@ -31,10 +31,10 @@ import { THROTTLING_WARNING_MSG, error, warn } from './helpers';
 
 type Mode = 'run' | 'push';
 
-export function normalizeOptions(
+export async function normalizeOptions(
   cliArgs: CliArgs,
   mode: Mode = 'run'
-): RunOptions {
+): Promise<RunOptions> {
   const options: RunOptions = {
     ...cliArgs,
     environment: process.env['NODE_ENV'] || 'development',
@@ -85,7 +85,7 @@ export function normalizeOptions(
    */
   const config =
     cliArgs.config || !cliArgs.inline
-      ? readConfig(options.environment, cliArgs.config)
+      ? await readConfig(options.environment, cliArgs.config)
       : {};
 
   /**