The Node.js Runtime
Cloud Functions supports the following Node.js runtimes:
- Node.js 20
- Node.js 18 (recommended)
- Node.js 16
- Node.js 14
- Node.js 12
- Node.js 10
For instructions on how to run your Node.js function locally, see Running Functions with Functions Framework.
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.
gcloud
If you are using the Google Cloud CLI, you can specify the runtime
by using the --runtime
parameter. For example:
gcloud functions deploy NAME --runtime nodejs20 --trigger-http
For more arguments that you can specify when you are deploying, see Deploy using the gcloud tool.
Console
If you are using the Google Cloud console, you can select the runtime when you create and deploy a function. See the Google Cloud console quickstart for detailed instructions.
Execution environment
The execution environment includes the runtime, the operating system, packages, and a library that invokes your function.
The Node.js version 18 runtime uses an execution environment based on Ubuntu 22.04. Node.js runtimes earlier than version 18 are 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.
Specifying dependencies
You can specify dependencies for your functions by listing them in a
package.json
file. For more information, see
Specifying dependencies in Node.js.
NPM build script
By default, the Node.js runtime executes npm run build
if a build
script
is detected in package.json
. If you require additional control over your build
steps before starting your application, you can provide a custom build step
by adding a gcp-build
script to your package.json
file.
You can prevent your build from running the npm run build
script by either:
Adding a
gcp-build
script with an empty value in yourpackage.json
file:"gcp-build":""
.Setting the build environment variable
GOOGLE_NODE_RUN_SCRIPTS
to the empty string to prevent all scripts from running.
Signalling function termination
When working with asynchronous tasks that involve callbacks or Promise
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. The key is that your code must wait for the
asynchronous task or Promise
to complete before returning; otherwise the
asynchronous component of your function may be terminated before it completes.
Event-driven functions
Implicit return
exports.implicitlyReturning = async (event, context) => {
return await asyncFunctionThatReturnsAPromise();
};
Explicit return
exports.explicitlyReturning = function (event, context) {
return asyncFunctionThatReturnsAPromise();
};
HTTP functions
Node.js
Using middleware to handle HTTP requests
Node.js HTTP Cloud Functions provide request
and response
objects
that are compatible with
ExpressJS
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.
Using ES Modules
ECMAScript modules (ES modules or ESM) are a TC39 standard, unflagged feature
in Node version 14+ for loading JavaScript modules. Unlike CommonJS, ESM
provides an asynchronous API for loading modules. It also provides a popular
syntax improvement via import
and export
statements that can be used within
a Cloud Function (instead of require
statements).
To use ESM within a Cloud Function, you must declare "type": "module"
within
your package.json
.
{
...
"type": "module",
...
}
Then you can use import
and export
statements.