Serverless Helper

A framework to implement serverless framework config file with ease and standarized resources.

Installation

npm install sls-helper

Usage

// serverless.js

const { helper } = require('sls-helper');

module.exports = helper({
    hooks: [

        ['bucket', {
            resourceName: 'ServiceBucket',
            name: 'my-bucket'
        }],

        'custom.myHelperWithoutConfigs'
    ]
});

Plugins

In order to implement a plugin for the framework, you must publish a package with the following pattern: sls-helper-plugin-{plugin-name}.

The plugin-name must then be used as a prefix to use a helper of that plugin, for example: plugin-name.helperName

The package must export an object mapping helper names to helper implementations.

Each helper is a function that receives the following arguments:

• serviceConfig: The current service config object
• helperParams: The (optional) configuration for the helper.

It also has to return the new service config object.

Plugin list:

• JANIS

Core Helpers

S3 Bucket (bucket)

Used to implement a bucket with blocked public access

Option	Type	Description	Attributes	Default value
resourceName	string	The logical name of the bucket	Required
name	string	The bucket name	Required
acl	string	The bucket acl		Private
cors	boolean | object | array	The bucket CORS configuration. If set to true, default configuration is set (every origin, every header)
cors.id, cors[].id	string	The CORS rule ID
cors.origin, cors[].origin	array | string | boolean	The CORS rule origin(s) (if value is true, it's set as every origin)
cors.methods, cors[].methods	array | string	The CORS rule method(s)
cors.headers, cors[].headers	array | string	The CORS rule headers(s)
cors.exposedHeaders, cors[].exposedHeaders	array | string	The CORS rule exposed headers(s)
cors.maxAge, cors[].maxAge	number	The CORS rule max age
tags	object	A key-value object of tags to associate to the bucket
rawProps	object	Extra raw properties	See the official documentation

Example

const { helper } = require('sls-helper');

module.exports = helper({
    hooks: [
        ['bucket', {
            resourceName: 'ServiceBucket',
            name: 'my-bucket'
        }]
    ]
});

IAM Role Statement (iamStatement)

(since 1.2.0)

Used to implement an IAM Role statement for your service

Option	Type	Description	Attributes	Default value
effect	string	The IAM statement effect	Enum('Allow', 'Deny')	'Allow'
action	string | array<string>	The IAM statement action	Required
resource	string | array<string>	The IAM statement resource	Required

Example

const { helper } = require('sls-helper');

module.exports = helper({
    hooks: [
        ['iamStatement', {
            action: [
                's3:PutObject',
                's3:GetObject'
            ],
            resource: 'arn:aws:s3:::my-bucket/*'
        }]
    ]
});

API Lambda Proxy (apiLambdaProxy)

Used to implement Lambda Proxy APIs

Option	Type	Description	Attributes	Default value
functionName	string	The function name	Required
handler	string	The function handler	Required
description	string	The function description
path	string	The API path	Required
method	string	The API HTTP method	Required
useApiKey	boolean	Whether the API requires API key or not		false
queryParameters	object	A key value to map query string parameters to a boolean indicating if it's required or not
requestHeaders	object	A key value to map headers to a boolean indicating if it's required or not
authorizer	string	The authorizer config	See the official documentation
cors	object | boolean	See the official documentation
async	boolean	Whether the API will execute as an async lambda or not		false

Example

const { helper } = require('sls-helper');

module.exports = helper({
    hooks: [
        ['apiLambdaProxy', {
            functionName: 'MyFunctionName',
            handler: 'path/to/my.handler',
            path: '/hello-world',
            method: 'get'
        }]
    ]
});

Lambda Function (function)

(since 1.1.0)

Used to implement Lambda Functions

Option	Type	Description	Attributes	Default value
functionName	string	The function name	Required
handler	string	The function handler	Required
description	string	The function description
events	array[object]	The function events
timeout	number	The function timeout
package.include	array[string]	The List of paths of files to include

Example

const { helper } = require('sls-helper');

module.exports = helper({
    hooks: [
        ['function', {
            functionName: 'MyFunctionName',
            handler: 'path/to/my.handler',
            events: [
                {
                    schedule: 'rate(1 hour)',
                },
                {
                    s3: {
                        bucket: 'myBucket',
                        event: 's3:ObjectCreated:*',
                        rules: [
                            { prefix: 'somePrefix' },
                            { suffix: 'someSuffix' }
                        ]
                    }
                }
            ]
        }]
    ]
});

Environment variables (envVars)

(since 1.3.0)

Used to implement environment variables

Configuration options are the environment variables key-value object

Example

const { helper } = require('sls-helper');

module.exports = helper({
    hooks: [
        ['envVars', {
            MY_VAR: 'and the value',
            SOME_OTHER_VAR: 'and some other value'
        }]
    ]
});

Resource (resource)

(since 1.8.0)

Used to implement custom resources

Option	Type	Description	Attributes	Default value
name	string	The resource logical name	Required
resource	object	The resource configuration object for Cloudformation	Required

Example

const { helper } = require('sls-helper');

module.exports = helper({
    hooks: [
        ['resource', {
            name: 'MyQueue',
            resource: {
                Type: 'AWS::SQS::Queue',
                Properties: {
                    QueueName: 'my-super-queue'
                }
            }
        }]
    ]
});