Cloud Functions supports the following Node.js runtimes:
- Node.js 10
- Node.js 12
- Node.js 14
For instructions on how to run your Node.js function locally, see Running Functions with Function Frameworks.
To get started with Node.js on Cloud Functions, see the Quickstart.
Selecting the runtime
You can select the desired Node.js runtime for your function during deployment.
If you are using the
gcloud command-line tool, you can specify the runtime
by using the
--runtime parameter. For example:
gcloud functions deploy NAME --runtime nodejs14 --trigger-http
For more arguments that you can specify when you are deploying, see Deploy using the gcloud tool.
If you are using the Cloud Console, you can select the runtime when you create and deploy a function. See the Cloud Console quickstart for detailed instructions.
The execution environment includes the runtime, the operating system, packages, and a library that invokes your function.
The Node.js runtimes use an execution environment based on Ubuntu 18.04. See Cloud Functions Execution Environment for more information.
The library that invokes your function is the Node Functions Framework.
Source code structure
In order for Cloud Functions to find your function's definition, each runtime has certain structuring requirements for your source code. See Writing Cloud Functions for more information.
You can specify dependencies for your functions by listing them in a
package.json file. For more information, see
Specifying dependencies in Node.js.
The Node.js 10+ runtimes automatically set fewer environment variables than
previous runtimes supported by Cloud Functions, and for Node.js 12+
functions with memory limits greater than 2GiB, users need to
NODE_OPTIONS to have
For details, see
Using Environment Variables.
Signalling function termination
When working with asynchronous tasks that involve callbacks or
objects, you must explicitly inform the runtime that your function has finished
executing these tasks. You can do this in several different ways, as shown in
the samples below.
// Await-ing promises within functions is OK if you don't return anything await Promise.resolve(); // These will cause background tasks to stop executing immediately return 1; // OK: returning a value return (await Promise.resolve()); // WRONG: returning the result of a promise return (await Promise.reject()); // WRONG: same behavior as resolved promises // These will wait until the related background task finishes return Promise.resolve(); // OK: returning the promise itself return Promise.reject(); // OK: same behavior as to-be-resolved promises
// OK: await-ing a Promise before sending an HTTP response await Promise.resolve(); // WRONG: HTTP functions should send an // HTTP response instead of returning. return Promise.resolve() // HTTP functions should signal termination by returning an HTTP response. // This should not be done until all background tasks are complete. res.send(200); res.end(); // WRONG: this may not execute since an // HTTP response has already been sent. return Promise.resolve()
Using middleware to handle HTTP requests
Node.js HTTP Cloud Functions provide
that are compatible with
to make consuming HTTP requests simple. Cloud Functions automatically reads the
request body, so you will always receive the body of a request independent of
the content type. This means that HTTP requests should be considered to have
been fully read by the time your code is executed. The nesting of ExpressJS
apps should be used with this caveat—specifically, middleware that expects the
body of a request to be unread might not behave as expected.