lambchop

Lambchop

It is a tool that invoke AWS Lambda function from the local machine as a normally script.

Installation

Add this line to your application's Gemfile:

gem 'lambchop'

And then execute:

$ bundle

Or install it yourself as:

$ gem install lambchop

Usage

Terminal 1:

$ export AWS_ACCESS_KEY_ID=...
$ export AWS_SECRET_ACCESS_KEY=...
$ export AWS_REGION=us-east-1

$ cat test.js
#!/usr/bin/env lambchop
/*
function_name: test # default: file name without ext
runtime: nodejs     # default: nodejs
description: ''     # default: (empty)
timeout: 3          # default: 3
memory_size: 128    # default: 128
role: arn:aws:iam::NNNNNNNNNNNN:role/lambda_exec_role
handler: test.handler
include_files: */*  # default: nil
# Handler module name is filename.
# `handler:` is `index.handler` when filename is `index.js`
*/
console.log('Loading event');

exports.handler = function(event, context) {
    console.log('value1 = ' + event.key1);
    console.log('value2 = ' + event.key2);
    console.log('value3 = ' + event.key3);
    context.succeed('Hello World');
};

$ ./test.js
(Wait event...)

Terminal 2:

$ export AWS_ACCESS_KEY_ID=...
$ export AWS_SECRET_ACCESS_KEY=...
$ export AWS_REGION=us-east-1

$ lambchop-cat
usage: lambchop-cat <function-name>

$ echo '{"key1":100, "key2":200, "key3":300}' | lambchop-cat test
---
status_code: 200
function_error:
payload: '"Hello World"'

Terminal 1:

(Wait event...)
2014-11-23T08:06:53.212Z  xxxxxxxxxxxxxxxx  Loading event
START RequestId: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
2014-11-23T08:06:53.330Z  xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx  value1 = 100
2014-11-23T08:06:53.330Z  xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx  value3 = 300
2014-11-23T08:06:53.330Z  xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx  value2 = 200
END RequestId: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
REPORT RequestId: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx  Duration: 117.54 ms Billed Duration: 200 ms   Memory Size: 128 MB Max Memory Used: 9 MB

Invoke async

$ echo '{"key1":100, "key2":200, "key3":300}' | lambchop-cat test -t event
---
status_code: 202
function_error:
payload: ''

Invoke with tail

$ echo '{"key1":100, "key2":200, "key3":300}' | lambchop-cat test -l tail
status_code: 200
function_error:
payload: '"Hello world!"'
log_result: |-
  2014-11-23T08:06:53.212Z  xxxxxxxxxxxxxxxx  Loading event
  START RequestId: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
  2014-11-23T08:06:53.330Z  xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx  value1 = 100
  2014-11-23T08:06:53.330Z  xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx  value3 = 300
  2014-11-23T08:06:53.330Z  xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx  value2 = 200
  END RequestId: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
  REPORT RequestId: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx  Duration: 117.54 ms Billed Duration: 200 ms   Memory Size: 128 MB Max Memory Used: 9 MB

DryRun

$ echo '{"key1":100, "key2":200, "key3":300}' | lambchop-cat test -t dry_run
---
status_code: 204
function_error:
payload: ''

Dump function

$ lambchop-dump
usage: lambchop-dump <function-name>

$ lambchop-dump test
#!/usr/bin/env lambchop
/*
function_name: test
runtime: nodejs
role: arn:aws:iam::NNNNNNNNNNNN:role/lambda_exec_role
handler: test.handler
description: ''
timeout: 3
memory_size: 128
*/
console.log('Loading event');

exports.handler = function(event, context) {
    console.log('value1 = ' + event.key1);
    console.log('value2 = ' + event.key2);
    console.log('value3 = ' + event.key3);
    context.succeed('Hello World');
};

Upload only

#!/usr/bin/env lambchop -d
...

Use ERB as preprocessor

#!/usr/bin/env lambchop -e
...

Follow log only

~$ lambchop-tail
usage: lambchop-tail <function-name>

~$ lambchop-tail test
START RequestId: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
...

node module path

.
├── lambda-script.js
└── node_modules/

Include extra files

#!/usr/bin/env lambchop
/*
...
include_files: *.txt
*/
...

Diff

$ lambchop-diff
usage: lambchop-cat <function-name> <file>

$ lambchop-diff test ./test.js
--- test:test.js
+++ ./test.js
@@ -1,11 +1,11 @@
 var http = require('http');

 exports.handler = function(event, context) {
-  http.get('http://example.com/', function(res) {
+  http.get('http://www.yahoo.com/', function(res) {
     res.setEncoding('utf8');
     res.on('data', function(str) {
       console.log(str);
       context.done();
     });
   });
 };

Demo

• https://asciinema.org/a/14158