https://github.com/ffleet/shim
AWS Lambda serverless shim helper library for node.js
https://github.com/ffleet/shim
aws ffleet lambda nodejs serverless
Last synced: 3 months ago
JSON representation
AWS Lambda serverless shim helper library for node.js
- Host: GitHub
- URL: https://github.com/ffleet/shim
- Owner: ffleet
- License: mit
- Created: 2018-07-06T16:26:04.000Z (over 7 years ago)
- Default Branch: master
- Last Pushed: 2018-08-10T04:06:17.000Z (over 7 years ago)
- Last Synced: 2025-08-14T13:20:57.493Z (8 months ago)
- Topics: aws, ffleet, lambda, nodejs, serverless
- Language: JavaScript
- Homepage: https://ffleet.io
- Size: 98.6 KB
- Stars: 7
- Watchers: 3
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
- awesome-serverless - Lambda Shim - A node.js shim library to simplify Lambda function development (Others)
README
# AWS Lambda Shim
[](#readme)
[](https://www.npmjs.com/package/@ffleet/shim)
> A Better Lambda API
This library provides an abstraction between the AWS Lambda events and classic node.js calling conventions.
This project is sponsored by the Functional Fleet [Serverless Platform](https://ffleet.io). We are currently accepting beta users for our platform, featuring a free git repo, hosted deploy queue, and centralized monitoring.
## Why
AWS Lambda has a somewhat unintuitive API structure that is sometimes inconsistent with node.js standards. This library bridges the gap, allowing you to write more familiar node.js style code.
## Wrap
Wrapping your function standardizes the calling conventions across all versions of Node.js and all AWS Lambda event sources. This includes:
* Supporting `Promise` returns, rather than the callback argument
* Standardizing arguments to `(event, callback)`
* Providing additional helpers through the `this` object
Example:
```js
var shim = require('@ffleet/shim');
var myLib = require('./lib');
// callback is not needed with Promise
function myHandler(event) {
// myLib.handle returns a promise
return myLib.handle(event);
}
exports.myHandler = shim.wrap(myHandler);
```
## Libraries
The specific API shims below provide context specific APIs for certain Lambda events.
### HTTP
Node.js HTTP servers are built around `request` and `response` objects passing through route handlers. This has been embraced by the common node.js HTTP libraries as well (Express, Hapi, Restify, etc.).
The `http` shim creates a native node.js HTTP server and proxies the AWS Lambda event.
For example, using a native handler:
```js
const shim = require('@ffleet/shim');
function myNativeHttpHandler(req, res) {
res.end('Hello, World!');
}
exports.myNativeHttpHandler = shim.http(myNativeHttpHandler);
```
Or, you can wrap an entire Express server:
```js
const shim = require('@ffleet/shim');
const express = require('express');
const app = express();
app.get('/', function(req, res, next) {
res.send('Hello, World!');
});
exports.myExpressHttpHandler = shim.http(app);
```
### Cron
Cron functions are executed by AWS CloudWatch Events. Wrapping with the `cron` shim unpacks the event data and provides a `Date` object of when the cron event was generated.
```js
const shim = require('@ffleet/shim');
function myCron(date, callback) {
console.log('cron event generated at ' + date.toISOString());
}
exports.myCron = shim.cron(myCron);
```
### Logs
AWS CloudWatch Log data is provided in a base64 encoded and gzip packed data string. The `logs` shim will decode the log data and reconstitute the represented JSON object, as:
```json
{
"messageType": "DATA_MESSAGE",
"owner": "123456789123",
"logGroup": "testLogGroup",
"logStream": "testLogStream",
"subscriptionFilters": ["testFilter"],
"logEvents": [{
"id": "eventId1",
"timestamp": 1440442987000,
"message": "[ERROR] First test message"
}, {
"id": "eventId2",
"timestamp": 1440442987001,
"message": "[ERROR] Second test message"
}]
}
```
Example:
```js
const shim = require('@ffleet/shim');
function myLogHandler(logObject, callback) {
logObject.logEvents.forEach(logEvent => console.log('log', logEvent));
}
exports.myLogHandler = shim.logs(myLogHandler);
```
## License
MIT License
Copyright (c) 2018 Functional Fleet
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.