angular-cn/dev-infra/utils/child-process.ts

83 lines
3.1 KiB
TypeScript

/**
* @license
* Copyright Google LLC All Rights Reserved.
*
* Use of this source code is governed by an MIT-style license that can be
* found in the LICENSE file at https://angular.io/license
*/
import {spawn, SpawnOptions} from 'child_process';
import {debug, error} from './console';
/** Interface describing the options for spawning a process. */
export interface SpawnedProcessOptions extends Omit<SpawnOptions, 'stdio'> {
/** Console output mode. Defaults to "enabled". */
mode?: 'enabled'|'silent'|'on-error';
}
/** Interface describing the result of a spawned process. */
export interface SpawnedProcessResult {
/** Captured stdout in string format. */
stdout: string;
}
/**
* Spawns a given command with the specified arguments inside a shell. All process stdout
* output is captured and returned as resolution on completion. Depending on the chosen
* output mode, stdout/stderr output is also printed to the console, or only on error.
*
* @returns a Promise resolving with captured stdout on success. The promise
* rejects on command failure.
*/
export function spawnWithDebugOutput(
command: string, args: string[],
options: SpawnedProcessOptions = {}): Promise<SpawnedProcessResult> {
return new Promise((resolve, reject) => {
const commandText = `${command} ${args.join(' ')}`;
const outputMode = options.mode;
debug(`Executing command: ${commandText}`);
const childProcess =
spawn(command, args, {...options, shell: true, stdio: ['inherit', 'pipe', 'pipe']});
let logOutput = '';
let stdout = '';
// Capture the stdout separately so that it can be passed as resolve value.
// This is useful if commands return parsable stdout.
childProcess.stderr.on('data', message => {
logOutput += message;
// If console output is enabled, print the message directly to the stderr. Note that
// we intentionally print all output to stderr as stdout should not be polluted.
if (outputMode === undefined || outputMode === 'enabled') {
process.stderr.write(message);
}
});
childProcess.stdout.on('data', message => {
stdout += message;
logOutput += message;
// If console output is enabled, print the message directly to the stderr. Note that
// we intentionally print all output to stderr as stdout should not be polluted.
if (outputMode === undefined || outputMode === 'enabled') {
process.stderr.write(message);
}
});
childProcess.on('exit', (status, signal) => {
const exitDescription = status !== null ? `exit code "${status}"` : `signal "${signal}"`;
const printFn = outputMode === 'on-error' ? error : debug;
printFn(`Command "${commandText}" completed with ${exitDescription}.`);
printFn(`Process output: \n${logOutput}`);
// On success, resolve the promise. Otherwise reject with the captured stderr
// and stdout log output if the output mode was set to `silent`.
if (status === 0) {
resolve({stdout});
} else {
reject(outputMode === 'silent' ? logOutput : undefined);
}
});
});
}