functions-framework-nodejs

The Functions Framework lets you write lightweight functions that run in OpenFunction, supports different kinds of function signature type. All you need to do is providing a function and specify a few params.

Quickstarts

Openfunction Style

Quickstart: "Hello, World" on your local machine

1. Install the functions framework:

   $ npm install -g @openfunction/functions-framework

2. Create an index.js file with the following contents:

   exports.helloWorld = (data) => {
     return 'Hello, World';
   };

3. Run the following command:

   $ npx @openfunction/functions-framework --target=helloWorld --source openfunction

4. Open http://localhost:8080/ in your browser and see {"data": "Hello, World"}.

Quickstart: Set up a new project

1. Create a package.json file using npm init:

   $ npm init

2. Create an index.js file with the following contents:

   exports.helloWorld = (data) => {
     return 'Hello, World';
   };

3. Now install the Functions Framework:

   $ npm install @openfunction/functions-framework

4. Add a start script to package.json, with configuration passed via command-line arguments:

     "scripts": {
       "start": "functions-framework --target=helloWorld --source openfunction"
     }

5. Use npm start to start the built-in local development server:

   $ npm start
   ...
   The functionModulePath is: /.../.../index.js
   Openfunction functions framework listening at http://localhost:8080

6. Send requests to this function using curl from another terminal window:

   $ curl localhost:8080
   # Output: {"data": "Hello, World"}

HTTP Style

Quickstart: Set up a new project

1. Create a package.json file using npm init:

   $ npm init

2. Create an index.js file with the following contents:

   exports.helloWorld = (req, res) => {
     res.send('Hello, World');
   };

3. Now install the Functions Framework:

   $ npm install @openfunction/functions-framework

4. Add a start script to package.json, with configuration passed via command-line arguments:

     "scripts": {
       "start": "functions-framework --target=helloWorld --source openfunction http"
     }

5. Use npm start to start the built-in local development server:

   $ npm start
   ...
   The functionModulePath is: /.../.../index.js
   Openfunction functions framework listening at http://localhost:8080

6. Send requests to this function using curl from another terminal window:

   $ curl localhost:8080
   # Output: Hello, World

Define Your Function

By default, functions framework see the incoming request as a Openfunction request, so the simplest function can be like this:

/**
 * Send {"data": "Hello, World"}
 * @param data - data is the request body contents, which should be a json object
 */
exports.helloWorld = (data) => {
  return 'Hello, World';
};

Function framework support the following type of function source:

• OpenFunction (OpenFunction native type)
• HTTP
• CloudEvent

Here are some examples to give you a quick view of functions definition in different function source type.

Configure the Functions Framework

You can configure the Functions Framework using command-line flags.

Flag	Required	Description
-p, --port	False	The port on which the Functions Framework listens for requests. Default: 8080
-t, --target	True	The name of the exported function to be invoked in response to requests.
-s, --source	False	Function source type. Default: http; accepted values: http or or cloudevent or openfunction

You can set command-line flags in your package.json via the start script. For example:

  "scripts": {
    "start": "functions-framework --target=helloWorld --source cloudevent"
  }