Pac file support

package.json

@@ -31,7 +31,6 @@
     "@babel/eslint-parser": "^7.14.7",
     "@babel/preset-env": "^7.14.7",
     "@babel/register": "^7.17.7",
-    "babel-plugin-transform-import-meta": "^2.2.1",
     "@rollup/plugin-alias": "^5.1.1",
     "@rollup/plugin-babel": "^6.0.0",
     "@rollup/plugin-commonjs": "^21.0.0",

packages/client/src/client.js

@@ -19,7 +19,7 @@ import {
 
 // Default client API URL can be set with an env var for API development
 const { PERCY_CLIENT_API_URL = 'https://percy.io/api/v1' } = process.env;
-const pkg = getPackageJSON(import.meta.url);
+let pkg = getPackageJSON(import.meta.url);
 // minimum polling interval milliseconds
 const MIN_POLLING_INTERVAL = 1_000;
 const INVALID_TOKEN_ERROR_MESSAGE = 'Unable to retrieve snapshot details with write access token. Kindly use a full access token for retrieving snapshot details with Synchronous CLI.';
@@ -83,6 +83,8 @@ export class PercyClient {
 
   // Stringifies client and environment info.
   userAgent() {
+    if (this.env.forcedPkgValue) pkg = this.env.forcedPkgValue;
+
     let client = new Set([`Percy/${/\w+$/.exec(this.apiUrl)}`]
       .concat(`${pkg.name}/${pkg.version}`, ...this.clientInfo)
       .filter(Boolean));

packages/client/src/proxy.js

@@ -4,10 +4,28 @@ import http from 'http';
 import https from 'https';
 import logger from '@percy/logger';
 import { stripQuotesAndSpaces } from '@percy/env/utils';
+import { PacProxyAgent } from 'pac-proxy-agent';
 
 const CRLF = '\r\n';
 const STATUS_REG = /^HTTP\/1.[01] (\d*)/;
 
+// function to create PAC proxy agent
+function createPacAgent(pacUrl, options = {}) {
+  pacUrl = stripQuotesAndSpaces(pacUrl);
+  try {
+    const agent = new PacProxyAgent(pacUrl, {
+      keepAlive: true,
+      ...options
+    });
+
+    logger('client:proxy').info(`Successfully loaded PAC file from: ${pacUrl}`);
+    return agent;
+  } catch (error) {
+    logger('client:proxy').error(`Failed to load PAC file, error message: ${error.message},  stack: ${error.stack}`);
+    throw new Error(`Failed to initialize PAC proxy: ${error.message}`);
+  }
+}
+
 // Returns true if the URL hostname matches any patterns
 export function hostnameMatches(patterns, url) {
   let subject = new URL(url);
@@ -219,11 +237,31 @@ export function proxyAgentFor(url, options) {
   let { protocol, hostname } = new URL(url);
   let cachekey = `${protocol}//${hostname}`;
 
-  if (!cache.has(cachekey)) {
-    cache.set(cachekey, protocol === 'https:'
-      ? new ProxyHttpsAgent(options)
-      : new ProxyHttpAgent(options));
+  // If we already have a cached agent, return it
+  if (cache.has(cachekey)) {
+    return cache.get(cachekey);
   }
 
-  return cache.get(cachekey);
+  try {
+    let agent;
+    const pacUrl = process.env.PERCY_PAC_FILE_URL;
+
+    // If PAC URL is provided, use PAC proxy
+    if (pacUrl) {
+      logger('client:proxy').info(`Using PAC file from: ${pacUrl}`);
+      agent = createPacAgent(pacUrl, options);
+    } else {
+      // Fall back to other proxy configuration
+      agent = protocol === 'https:'
+        ? new ProxyHttpsAgent(options)
+        : new ProxyHttpAgent(options);
+    }
+
+    // Cache the created agent
+    cache.set(cachekey, agent);
+    return agent;
+  } catch (error) {
+    logger('client:proxy').error(`Failed to create proxy agent: ${error.message}`);
+    throw error;
+  }
 }

packages/client/src/utils.js

@@ -40,6 +40,9 @@ export function getPackageJSON(rel) {
   /* istanbul ignore else: sanity check */
   if (rel.startsWith('file:')) rel = url.fileURLToPath(rel);
 
+  /* istanbul ignore else: sanity check */
+  if (rel.startsWith('file:')) rel = url.fileURLToPath(rel);
+
   let pkg = path.join(rel, 'package.json');
   if (fs.existsSync(pkg)) return JSON.parse(fs.readFileSync(pkg));
 
@@ -135,7 +138,9 @@ export async function request(url, options = {}, callback) {
   let { protocol, hostname, port, pathname, search, hash } = new URL(url);
 
   // reference the default export so tests can mock it
-  let { default: http } = await import(protocol === 'https:' ? 'https' : 'http');
+  // bundling cli inside electron or another package fails if we import it
+  // like this: await import(protocol === 'https:' ? 'https' : 'http');
+  let { default: http } = protocol === 'https:' ? await import('https') : await import('http');
   let { proxyAgentFor } = await import('./proxy.js');
 
   // automatically stringify body content

packages/core/src/api.js

@@ -1,13 +1,34 @@
 import fs from 'fs';
-import path from 'path';
-import { createRequire } from 'module';
+import path, { dirname, resolve } from 'path';
 import logger from '@percy/logger';
 import { normalize } from '@percy/config/utils';
 import { getPackageJSON, Server, percyAutomateRequestHandler, percyBuildEventHandler } from './utils.js';
 import WebdriverUtils from '@percy/webdriver-utils';
 import { handleSyncJob } from './snapshot.js';
-// need require.resolve until import.meta.resolve can be transpiled
-export const PERCY_DOM = createRequire(import.meta.url).resolve('@percy/dom');
+// Previously, we used `createRequire(import.meta.url).resolve` to resolve the path to the module.
+// This approach relied on `createRequire`, which is Node.js-specific and less compatible with modern ESM (ECMAScript Module) standards.
+// This was leading to hard coded paths when CLI is used as a dependency in another project.
+// Now, we use `fileURLToPath` and `path.resolve` to determine the absolute path in a way that's more aligned with ESM conventions.
+// This change ensures better compatibility and avoids relying on Node.js-specific APIs that might cause issues in ESM environments.
+import { fileURLToPath } from 'url';
+
+const getPercyDomPath = () => {
+  try {
+    const { createRequire } = require('module');
+    return createRequire(import.meta.url).resolve('@percy/dom');
+  } catch (error) {
+    logger('core:server').warn([
+      'Failed to resolve @percy/dom path using createRequire.',
+      'Falling back to using fileURLToPath and path.resolve.'
+    ].join(' '));
+  }
+  const __filename = fileURLToPath(import.meta.url);
+  const __dirname = dirname(__filename);
+  return resolve(__dirname, 'node_modules/@percy/dom');
+};
+
+// Resolved path for PERCY_DOM
+export const PERCY_DOM = getPercyDomPath();
 
 // Returns a URL encoded string of nested query params
 function encodeURLSearchParams(subj, prefix) {

packages/core/src/findRevision.sh

@@ -0,0 +1,37 @@
+#!/bin/bash
+
+function download_url {
+  if [[ "$OS" == "Linux" ]]; then
+    echo "https://www.googleapis.com/download/storage/v1/b/chromium-browser-snapshots/o/Linux_x64%2F${1}%2Fchrome-linux.zip?alt=media"
+  elif [[ "$OS" == "Mac" ]] || [[ "$OS" == "Mac_Arm" ]]; then
+    echo "https://www.googleapis.com/download/storage/v1/b/chromium-browser-snapshots/o/$OS%2F${1}%2Fchrome-mac.zip?alt=media"
+  elif [[ "$OS" == "Win" ]] || [[ "$OS" == "Win_x64" ]]; then
+    echo "https://www.googleapis.com/download/storage/v1/b/chromium-browser-snapshots/o/$OS%2F${1}%2Fchrome-win.zip?alt=media"
+  fi
+}
+
+function get_closest_rev {
+  while true; do
+    curl -I 2>/dev/null `download_url $REVISION` | head -1 | grep 404 >/dev/null
+    if (($? == 1)); then
+      break
+    fi
+    REVISION=$(($REVISION-1))
+  done
+  echo $REVISION
+}
+
+
+if (($# < 1)); then
+  printf "usage: \n"
+  printf "  ./get_chromuim [-r] rev    - will get chromium by revision\n"
+  exit 1
+fi
+
+export REVISION=$1
+
+for os in "Linux" "Mac" "Mac_Arm" "Win" "Win_x64";
+do
+  export OS=$os
+  echo "$OS" `get_closest_rev`
+done

packages/core/src/percy.js

@@ -5,12 +5,11 @@ import { getProxy } from '@percy/client/utils';
 import Browser from './browser.js';
 import Pako from 'pako';
 import {
-  base64encode
-  ,
+  base64encode,
   generatePromise,
   yieldAll,
-  yieldTo
-  , redactSecrets,
+  yieldTo,
+  redactSecrets,
   detectSystemProxyAndLog
 } from './utils.js';
 

packages/env/src/environment.js

@@ -297,6 +297,13 @@ export class PercyEnv {
   get token() {
     return this.vars.PERCY_TOKEN || null;
   }
+
+  // PERCY_FORCE_PKG_VALUE for forcing package.json values
+  // to be used as the current environment values in client
+  get forcedPkgValue() {
+    let pkg = this.vars.PERCY_FORCE_PKG_VALUE;
+    return JSON.parse(pkg) || null;
+  }
 }
 
 // cache getters on initial call so subsequent calls are not re-computed