Promise.config

Promise.config(Object {
    warnings: boolean=false,
    longStackTraces: boolean=false,
    cancellation: boolean=false,
    monitoring: boolean=false,
    asyncHooks: boolean=false
} options) -> Object;

Configure long stack traces, warnings, monitoring, async hooks and cancellation. Note that even though false is the default here, a development environment might be detected which automatically enables long stack traces and warnings. For webpack and browserify development environment is always enabled. See installation on how to configure webpack and browserify for production.

Promise.config({
    // Enable warnings
    warnings: true,
    // Enable long stack traces
    longStackTraces: true,
    // Enable cancellation
    cancellation: true,
    // Enable monitoring
    monitoring: true,
    // Enable async hooks
    asyncHooks: true,
});

You can configure the warning for checking forgotten return statements with wForgottenReturn:

Promise.config({
    // Enables all warnings except forgotten return statements.
    warnings: {
        wForgottenReturn: false
    }
});

wForgottenReturn is the only warning type that can be separately configured. The corresponding environmental variable key is BLUEBIRD_W_FORGOTTEN_RETURN.

In Node.js you may configure warnings and long stack traces for the entire process using environment variables:

BLUEBIRD_LONG_STACK_TRACES=1 BLUEBIRD_WARNINGS=1 node app.js

Both features are automatically enabled if the BLUEBIRD_DEBUG environment variable has been set or if the NODE_ENV environment variable is equal to "development".

Using the value 0 will explicitly disable a feature despite debug environment otherwise activating it:

# Warnings are disabled despite being in development environment
NODE_ENV=development BLUEBIRD_WARNINGS=0 node app.js

Cancellation is always configured separately per bluebird instance.

Async hooks

Bluebird supports async hooks in node versions 9.6.0 and later. After it is enabled promises from the bluebird instance are assigned unique asyncIds:

// Async hooks disabled for bluebird
const ah = require('async_hooks');
const Promise = require("bluebird");
Promise.resolve().then(() => {
    console.log(`eid ${ah.executionAsyncId()} tid ${ah.triggerAsyncId()}`);
    //
});

// Async hooks enabled for bluebird
const ah = require('async_hooks');
const Promise = require("bluebird");
Promise.config({asyncHooks: true});
Promise.resolve().then(() => {
    console.log(`eid ${ah.executionAsyncId()} tid ${ah.triggerAsyncId()}`);
    //
});