A grunt plugin to assist in developing functions for AWS Lambda.
This plugin provides helpers for:
- Running Lambda functions locally
- Managing npm dependencies which are required by your function
- Packaging required dependencies with your function in a Lambda compatible zip
- Uploading package to Lambda
This plugin requires Grunt ~0.4.5
If you haven't used Grunt before, be sure to check out the Getting Started guide, as it explains how to create a Gruntfile as well as install and use Grunt plugins. Once you're familiar with that process, you may install this plugin with this command:
npm install grunt-aws-lambda --save-devOnce the plugin has been installed, it may be enabled inside your Gruntfile with this line of JavaScript:
grunt.loadNpmTasks('grunt-aws-lambda');This will save you from packaging previous packages in future ones.
For example your .npmignore might look something like this:
event.json
Gruntfile.js
dist
*.iml
npm packages which should be bundled with your lambda function must be included in the bundledDependencies of your
package.json, for example:
...
"dependencies": {
"jquery": "2.1.1"
},
...
"bundledDependencies": [
"jquery"
]
...This will save you from accidentally committing AWS credentials.
This plugin contains 3 tasks:
- lambda_invoke - Wrapper to run and test lambda functions locally and view output.
- lambda_package - Packages function along with any npm dependencies in a zip format suitable for lambda.
- lambda_deploy - Uploads the zip package to lambda.
lambda_invoke and lambda_package can be used independently, lambda_deploy will invoke lambda_package before uploading the produced zip file.
In your project's Gruntfile, add a section named lambda_invoke to the data object passed into grunt.initConfig().
grunt.initConfig({
lambda_invoke: {
default: {
options: {
// Task-specific options go here.
}
}
},
});Type: String
Default value: handler
Name of the handler function to invoke.
Type: String
Default value: index.js
Name of your script file which contains your handler function.
Type: String
Default value: event.json
Name of the .json file containing your test event relative to your Gruntfile.
In this example, the default options are used therefore if we have the following in our Gruntfile.js:
grunt.initConfig({
lambda_invoke: {
default: {
options: {
// Task-specific options go here.
}
}
},
});And the following in index.js
exports.handler = function (event, context) {
console.log('value1 = ' + event.key1);
console.log('value2 = ' + event.key2);
console.log('value3 = ' + event.key3);
context.done(null, 'Hello World'); // SUCCESS with message
};And the following in event.json
{
"key1": "value1",
"key2": "value2",
"key3": "value3"
}Then we run grunt lambda_invoke, we should get the following output:
Running "lambda_invoke" task
value1 = value1
value2 = value2
value3 = value3
Message
-------
Hello World
Done, without errors.
This task generates a lambda package including npm dependencies using the default npm install functionality, therefore your dependencies must be included in the bundledDependencies section of your package.json to be included in the produced package.
In your project's Gruntfile, add a section named lambda_package to the data object passed into grunt.initConfig().
grunt.initConfig({
lambda_package: {
default: {
options: {
// Task-specific options go here.
}
}
},
});Type: Boolean
Default value: true
Whether or not to timestamp the packages, if set to true the current date/time will be included in the zip name, if false then the package name will be constant and consist of just the package name and version.
Type: String
Default value: ./
The path to your npm package, must contain the package.json file.
Type: String
Default value: dist
The folder where the complete zip files should be saved relative to the Gruntfile.
In this example, the default options are used therefore if we have the following in our Gruntfile.js:
grunt.initConfig({
lambda_package: {
default: {
options: {
// Task-specific options go here.
}
}
},
});And the following in package.json
{
"name": "my-lambda-function",
"description": "An Example Lamda Function",
"version": "0.0.1",
"private": "true",
"dependencies": {
"jquery": "2.1.1"
},
"devDependencies": {
"grunt": "0.4.*",
"grunt-pack": "0.1.*",
"grunt-aws-lambda": "0.1.*"
},
"bundledDependencies": [
"jquery"
]
}Then we run grunt lambda_package, we should see a new zip file in a new folder called dist called something like:
my-lambda-function_0-0-1_2014-10-30-18-29-4.zip
If you unzip that and look inside you should see something like:
index.js
package.json
node_modules/
node_modules/jquery
node_modules/jquery/... etc
Given that by default the dist folder is inside your function folder you can easily end up bundling previous packages inside subsequent packages therefore it is strongly advised that you add dist to your .npmignore.
For example your .npmignore might look something like this:
event.json
Gruntfile.js
dist
*.iml
In your project's Gruntfile, add a section named lambda_deploy to the data object passed into grunt.initConfig().
grunt.initConfig({
lambda_deploy: {
default: {
options: {
// Task-specific options go here.
},
function: 'my-lambda-function'
}
},
});Type: String
Default value: None - Required
The name of your target Lambda function, ie. the name of the function in the AWS console.
Type: String
Default value: Package name set by package task of same target - see below.
The name of the package to be uploaded.
When the lambda_package task runs it sets the package value for the lambda_deploy target with the same name.
Therefore if lambda_package and lambda_deploy have a target (eg. default) with the same name you will not need to provide this value - it will be passed automatically.
For example, your Gruntfile.js might contain the following:
grunt.initConfig({
lambda_deploy: {
default: {
function: 'my-lambda-function'
}
},
lambda_package: {
default: {
}
}
});You could then run grunt lambda_package lambda_deploy and it'll automatically create the package and deploy it without
having to specify a package name.
Type: String
Default value: null
If you wish to use a specific AWS credentials profile you can specify it here, otherwise it will use the environment default.
Type: String
Default value: us-east-1
Specify the AWS region, useful if you'd normally operate in a certain region (such as one where Lambda isn't yet available) but wish to upload functions to another region.
Type: Integer
Default value: null
Depending on your Lambda function, you might need to increase the timeout value. The default timeout assigned by AWS is currently 3 seconds.
If you wish to increase this timeout set the value here.
In this example, the default options are used therefore if we have the following in our Gruntfile.js:
grunt.initConfig({
lambda_deploy: {
default: {
function: 'my-lambda-function'
}
}
});And now if you run grunt lambda_deploy your package should be created and uploaded to the specified function.
In this example, the timeout value is increased to 10 seconds.
grunt.initConfig({
lambda_deploy: {
default: {
function: 'my-lambda-function',
timeout : 10
}
}
});You can combine the lambda_package and lambda_deploy into a single deploy task by adding the following to your Gruntfile.js:
grunt.registerTask('deploy', ['lambda_package', 'lambda_deploy']);You can then run grunt deploy to perform both these functions in one step.
The AWS SDK is configured to look for credentials in the environment, that is it will look in ~/.aws/credentials.
This file should look something like:
[default]
aws_access_key_id = <YOUR_ACCESS_KEY_ID>
aws_secret_access_key = <YOUR_SECRET_ACCESS_KEY>
For more information read this documentation.
To run the deploy command the AWS credentials require permissions to access lambda including lambda:UploadFunction and
iam:PassRole for the role which is assigned to the function.
It is recommended that the following two policies be applied to the user:
{
"Version": "2012-10-17",
"Statement": [
{
"Sid": "Stmt1404366560000",
"Effect": "Allow",
"Action": [
"lambda:*"
],
"Resource": [
"*"
]
}
]
}{
"Version": "2012-10-17",
"Statement": [
{
"Sid": "Stmt1404366560000",
"Effect": "Allow",
"Action": [
"iam:PassRole"
],
"Resource": [
"arn:aws:iam::<my_account_id>:role/<my_role_name>"
]
}
]
}In lieu of a formal styleguide, take care to maintain the existing coding style. Add unit tests for any new or changed functionality. Lint and test your code using Grunt.
- 0.1.0 - Initial release
- 0.2.0 - Adding some unit tests, refactoring deploy task into single task and converting tasks to multitasks
- 0.3.0 - Adding more warnings for various failure cases