concurrently
Version:
Run commands concurrently
78 lines (77 loc) • 4 kB
JavaScript
import Rx from 'rxjs';
import { delay, filter, map, share, switchMap, take } from 'rxjs/operators';
/**
* Provides logic to determine whether lists of commands ran successfully.
*/
export class CompletionListener {
successCondition;
scheduler;
constructor({ successCondition = 'all', scheduler, }) {
this.successCondition = successCondition;
this.scheduler = scheduler;
}
isSuccess(events) {
if (!events.length) {
// When every command was aborted, consider a success.
return true;
}
if (this.successCondition === 'first') {
return events[0].exitCode === 0;
}
else if (this.successCondition === 'last') {
return events[events.length - 1].exitCode === 0;
}
const commandSyntaxMatch = this.successCondition.match(/^!?command-(.+)$/);
if (commandSyntaxMatch == null) {
// If not a `command-` syntax, then it's an 'all' condition or it's treated as such.
return events.every(({ exitCode }) => exitCode === 0);
}
// Check `command-` syntax condition.
// Note that a command's `name` is not necessarily unique,
// in which case all of them must meet the success condition.
const nameOrIndex = commandSyntaxMatch[1];
const targetCommandsEvents = events.filter(({ command, index }) => command.name === nameOrIndex || index === Number(nameOrIndex));
if (this.successCondition.startsWith('!')) {
// All commands except the specified ones must exit successfully
return events.every((event) => targetCommandsEvents.includes(event) || event.exitCode === 0);
}
// Only the specified commands must exit successfully
return (targetCommandsEvents.length > 0 &&
targetCommandsEvents.every((event) => event.exitCode === 0));
}
/**
* Given a list of commands, wait for all of them to exit and then evaluate their exit codes.
*
* @returns A Promise that resolves if the success condition is met, or rejects otherwise.
* In either case, the value is a list of close events for commands that spawned.
* Commands that didn't spawn are filtered out.
*/
listen(commands, abortSignal) {
if (!commands.length) {
return Promise.resolve([]);
}
const abort = abortSignal &&
Rx.fromEvent(abortSignal, 'abort', { once: true }).pipe(
// The abort signal must happen before commands are killed, otherwise new commands
// might spawn. Because of this, it's not be possible to capture the close events
// without an immediate delay
delay(0, this.scheduler), map(() => undefined),
// #502 - node might warn of too many active listeners on this object if it isn't shared,
// as each command subscribes to abort event over and over
share());
const closeStreams = commands.map((command) => abort
? // Commands that have been started must close.
Rx.race(command.close, abort.pipe(filter(() => command.state === 'stopped')))
: command.close);
return Rx.lastValueFrom(Rx.combineLatest(closeStreams).pipe(filter(() => commands.every((command) => command.state !== 'started')), map((events) => events
// Filter out aborts, since they cannot be sorted and are considered success condition anyways
.filter((event) => event != null)
// Sort according to exit time
.sort((first, second) => first.timings.endDate.getTime() - second.timings.endDate.getTime())), switchMap((events) => this.isSuccess(events)
? this.emitWithScheduler(Rx.of(events))
: this.emitWithScheduler(Rx.throwError(() => events))), take(1)));
}
emitWithScheduler(input) {
return this.scheduler ? input.pipe(Rx.observeOn(this.scheduler)) : input;
}
}