@node-lambdas/cli

This CLI can be used to run or test cloud functions from a terminal.

How to install

Via NPM is the easiest:

npm i @node-lambdas/cli

If you don't have access to NPM registry, download the JS script and make it executable:

curl -o fn.mjs https://unpkg.com/@node-lambdas/cli@latest/fn.mjs
chmod +x fn.mjs

Introduction

A reusable cloud function is basically an HTTPS server:

input >> POST https://[service].jsfn.run/[function] >> output

For example: you have a JSON and you want to convert it to YAML, but you cannot install a program for that.

cat file.json | fn yaml encode | tee file.yml

Can I use it with cURL?

Absolutely!

curl -d @file.json https://yaml.jsfn.run/encode

Examples

# convert JSON to YAML
cat your.json | fn yaml

# calculate the sha256 hash for the content of file.txt
cat file.txt | fn sha 256

# convert Markdown to HTML
cat README.md | fn markdown

Run

Running any publicly available lambda or run your new project on localhost

Calling fn with a function name will pipe stdin to a cloud function and pipe the output back to stdout.

echo -n 'input' | fn [name]

# pipe file.txt to a lambda running in your machine
cat file.txt | fn +local

# pipe file.txt to a lambda running in your machine that uses port 2000
cat file.txt | fn +local +port=2000

You can see the available functions and read more in the index repository.

Run without input pipe

Usually you would use the syntax a | fn b to pipe data into a function. You can also add input options to fn instead, and bypass stdin.

Use +data='input data' to send the input data instead. You can also read from a file, using the +stdin=path/to/file, or the shortcut, @path/to/file.

For example:

fn data='hello' | fn base64
fn @input.txt | fn sha 512
fn +stdin=image.png | fn resize 1024x768

API Authentication

Some functions need credentials in order to run API calls. These credentials can be stored in a file called credentials.json.

The format is as follows:

• the top level keys are authentication groups. You use this name with +auth.
• each key under a group is a function name
• each key under a function maps to an HTTP header that the function needs.

For example: let's say you want to call the same function with different credentials:

{
  "default" {
    "function-name": {
      "access-key-id": "key-123",
      "access-key": "cac54b35c4ab6a5c46abb"
    },
    "another-name": {
      "authentication": "bearer cac54b35c4ab6a5c46abb"
    },
  },
  "bob-credentials": {
    "function-name": {
      "access-key-id": "key-456",
      "access-key": "4524bc45ba54ba45b25c2"
    },
  },
}

You can invoke the same function passing the authentication group to use:

# Using default credentials
echo 'let me in' | fn +auth function-name

# Using both default and 'bob-credentials' to pipe from one function call to another. The third call will not use any credentials
echo 'let me in' | fn +auth function-name | fn +auth=bob-credentials function-name | fn another-name

All options

| option | description | | ---------------- | ------------------------------------------------------------------------ | | +auth=[name] | Name of an authentication group to use from './credentials.json' | | +port=[number] | The http port to use when calling a local server with a running function | | +data=[data] | Use the data passed as argument instead of stdin for next step | | +nodata | Run the cloud function without any input | | +info name | Shows more details about a cloud function | | +json | Show cloud function API as JSON |