@meltwater/jackalambda
v1.13.8-0
Published
Mythical lambda creature
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Jackalambda
Mythical lambda creature.
Description
Toolkit for writing production ready Lambda functions.
Jackalambda provides a consistent way to write Lambda handlers that let you focus on the business logic of you function and none of the boilerplate.
With Jackalambda, you get:
- Consistent JSON logging.
- Cached remote secrets and configuration.
- AWS event detection and parsing.
- X-Ray enhanced clients for common AWS services.
- Distributed request id support.
- Isolated side effects for fully testable handlers.
- AVA logging integration.
All Jackalambda handlers follow a clear execution path:
- Resolve and validate all required configuration, or fail with a clear error.
- Isolate all side-effect producing dependencies in a container with their configuration.
- Run a processor function with a reference to the container.
- Ensure the logger is always available, scoped per-request, and always logs failures, event fatal ones.
Example
This project is a fully working, real world, example of using Jackalambda. Just check out the
handlers
folder.
Creating your first handler is this simple:
import { createHandler } from '@meltwater/jackalambda'
export handler = createHandler({
createProcessor: ({ log }) => (event, context) => {
log.info({ meta: event }, 'I 💖 Jackalambda')
return { success: true }
}
})
And here is how to add a side-effect that calls another lambda where the lambda ARN is stored in SSM:
import { createHandler, LambdaClient } from '@meltwater/jackalambda'
import { createSsmStringConfigurationRequest } from '@meltwater/aws-configuration-fetcher'
export handler = createHandler({
configurationRequests: [
createSsmStringConfigurationRequest(
'otherLambdaArn',
process.env.OTHER_LAMBDA_ARN_SSM_PATH
)
],
createContainer: (ctx, { otherLambdaArn }) => ({
otherLambdaClient: new LambdaClient({ arn: otherLambdaArn, ...ctx })
}),
createProcessor: ({ log }, { otherLambdaClient }) => (event, context) => {
log.info({ meta: event }, 'I 💖 Jackalambda')
return otherLambdaClient.invokeJson(event)
}
})
Installation
Add this as a dependency to your project using npm with
$ npm install @meltwater/jackalambda
or using Yarn with
$ yarn add @meltwater/jackalambda
Usage
For a full set of documentation check out the docs!
Development and Testing
Quickstart
$ git clone https://github.com/meltwater/jackalambda.git serverless-nodejs
$ cd serverless-nodejs
$ nvm install
$ yarn install
Run each command below in a separate terminal window:
$ yarn run offline
$ yarn run test:watch
Primary development tasks are defined under scripts
in package.json
and available via
yarn run
. View them with
$ yarn run
Source code
The source code is hosted on GitHub. Clone the project with
$ git clone [email protected]:meltwater/jackalambda.git
Requirements
You will need Node.js with npm, Yarn, and a Node.js debugging client.
Be sure that all commands run under the correct Node version, e.g., if using nvm, install the correct version with
$ nvm install
Set the active version for each shell session with
$ nvm use
Install the development dependencies with
$ yarn install
Drone
Drone should already be configured: this section is for reference only.
The following secrets must be set on Drone. These may be set manually or by running the script
./.drone/secrets.sh
.
Note the Drone config path must be set to .drone/config.yml
after the repo is activated.
npm
npm_token_ro
: npm token for installing packages.npm_token_rw
: npm token for publishing packages.npm_team
: npm team to grant read-only package access (formatorg:team
, optional).
Slack
slack_webhook
: Slack webhook for build notifications.
Drone Promotion
When the drone build publishes a new package version it can trigger a promotion event on a Drone repo.
drone_server
: Drone server.drone_token
: Drone token.
AWS S3 Release
aws_assume_role_arn_staging
: The AWS role to assume for staging.aws_assume_role_external_id_staging
: The external ID for the AWS role for staging.aws_assume_role_arn_production
: The AWS role to assume for production.aws_assume_role_external_id_production
: The external ID for the AWS role for production.
Publishing
Use the npm version
command to release a new version. This will push a new git tag
which will trigger a CI publish job.
Contributing
Please submit and comment on bug reports and feature requests.
To submit a patch:
- Fork it (https://github.com/meltwater/jackalambda/fork).
- Create your feature branch (
git checkout -b my-new-feature
). - Make changes.
- Commit your changes (
git commit -am 'Add some feature'
). - Push to the branch (
git push origin my-new-feature
). - Create a new Pull Request.
License
This npm package is licensed under the MIT license.
Warranty
This software is provided by the copyright holders and contributors "as is" and any express or implied warranties, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose are disclaimed. In no event shall the copyright holder or contributors be liable for any direct, indirect, incidental, special, exemplary, or consequential damages (including, but not limited to, procurement of substitute goods or services; loss of use, data, or profits; or business interruption) however caused and on any theory of liability, whether in contract, strict liability, or tort (including negligence or otherwise) arising in any way out of the use of this software, even if advised of the possibility of such damage.