tonyliu7870/aws-lambda-configuration-core

The core lambda function to manipulate configurations

aws-lambda-configuration front page

Assumed you had already setup your AWS access key, secret key and region (either in environment variable, aws profile, or any serverless framework supported way). ref: serverless - Credentials

Installation Guide (lazy version)

curl https://raw.githubusercontent.com/tonyliu7870/aws-lambda-configuration-core/master/lazy_setup.sh | bash

Installation Guide (step-by-step)

1. Download the source code
   Click "Download ZIP" from github or git clone [email protected]:tonyliu7870/aws-lambda-configuration-core.git or fork your own version (if you would like to save with your own settings).

2. Go to directory
   cd aws-lambda-configuration/

3. Install dependency
   yarn install or npm install

4. Transpile typescript code
   yarn build or npm run build

5. READ Configuration Storage part below

6. Deploy to AWS
   yarn deploy -- --stage dev --region us-east-1 or npm run deploy -- --stage dev --region us-east-1

Configuration Storage

aws-lambda-configuration use a DynamoDB table to store the configuration. By default, it sets up a new table named lambda-configurations for you via CloudFormation. However, it also DELETE the table BY DEFAULT when you remove aws-lambda-configuration via CloudFormation.
If you DO NOT want to include the DynamoDB resources into CloudFormation (recommended):

1. Disable the default table first: Open ./serverless.yml, comment out the whole resources part at the end by prepending a #.
2. Go to your AWS DynamoDB Console. Create a new table with any Table Name and Table settings. The table MUST has a Primary key named with configName and in String type.

API

This is a generic lambda function to handle all CRUD of the configuration. If you use the libraries, you may skip this part.

Parameter	Required?	Description
tableName	required	The dynamoDB table name used to store all the configurations. (default to be "lambda-configurations" but strongly recommended to be set)
documentName	required	The document name in the table to access the config. (default to be "settings" but strongly recommended to be set)
type	required	What to do with the config. Accept: "GET", "PUT", "DELETE", "CHECK"
key	optional	The path to sub-object of the config. undefined would refer to the whole document
data	required	The config object to set. Only available on "PUT"
noCache	optional	Will the core return a cached version if available. Only available on "GET" and "CHECK"

{
  tableName: string;
  documentName: string;
  type: string;
  key?: string;
  data?: any;
  noCache?: boolean;
}

API Example

Set (new document/replace whole document)

{
  "tableName": "myConfigTable",
  "documentName": "myConfig",
  "type": "PUT",
  "data": {
    "hello": "world",
    "something": {
      "sub": "data"
    },
    "another": [1,2,3,4,5]
  }
}

Set (partial update existing document)

{
  "tableName": "myConfigTable",
  "documentName": "myConfig",
  "type": "PUT",
  "key": "something.sub",
  "data": "data v2"
}

Note: You can not directly set a config via a virtual path, e.g. "key": "something.sub.some.path.that.do.not.exist". Instead, your possible options are:

• Get the whole config -> use lodash.set to update the config -> replace the whole config.
• Find the deepest existing path -> update by "key": "something.sub.some", "data": {"path":{"that":{"do":{"not":{"exist": "hi"}}}}}
• Consider how to restructure your configuration, e.g. flatten the config.

Get (whole config)

{
  "tableName": "myConfigTable",
  "documentName": "myConfig",
  "type": "GET",
  "noCache": true
}
// typeof result === 'object'
// result === {"hello":"world","something":{"sub": "data v2"},"another":[1,2,3,4,5]}

Get (one config)

{
  "tableName": "myConfigTable",
  "documentName": "myConfig",
  "type": "GET",
  "key": "something.sub"
  "noCache": false    // default is false, i.e. use cache if available
}
// typeof result === 'string'
// result === "data v2"

Has

{
  "tableName": "myConfigTable",
  "documentName": "user.id.012345",
  "type": "CHECK",
  // "key": "abcdef"
}
// typeof result === 'boolean'
// result === false
// If you adopt aws-lambda-configuration as your account management framework, this can be a mean to check whether a user exist.

Delete

{
  "tableName": "myConfigTable",
  "documentName": "myConfig",
  "type": "DELETE",
  // "key": "another[2]"
}

Uninstallation Guide

node_modules/.bin/serverless remove