A plugin for the Serverless Framework that simulates the behavior of AWS CloudFront Edge Lambdas while developing offline.
npm install --save-dev serverless
npm install --save-dev serverless-offline-edge-lambda
serverless.yml
service:
name: edge-lambdas
plugins:
- serverless-offline-edge-lambda
provider:
name: aws
runtime: nodejs12.x
functions:
lambda:
handler: src/handlers.onViewerRequest
lambdaAtEdge:
distribution: 'WebsiteDistribution'
eventType: 'viewer-request'
pathPattern: '/lambda'
resources:
Resources:
WebsiteDistribution:
Type: 'AWS::CloudFront::Distribution'
Properties:
DistributionConfig:
DefaultCacheBehavior:
npx serverless offline start --port=<port>
serverless-offline
The plugin should not be used in conjunction with serverless-offline
because both plugins define the offline
command.
serverless-plugin-cloudfront-lambda-edge
This plugin does not handle packaging and deploying edge lambdas to the cloud. Therefore
this plugin can be used with serverless-plugin-cloudfront-lambda-edge
. Again, doing so
is optional. The schema in serverless.yml derives from that used by serverless-plugin-cloudfront-lambda-edge
.
This plugin can also be used with transpilers such as serverless-plugin-typescript
. In the
cases where the transpiler outputs built files to a path that differs from the path
specified for the handlers (e.g. .build/src/handers.onViewerRequest), this plugin accepts
a configuration option path
that it uses to resolve function handlers.
plugins:
- serverless-plugin-typescript
custom:
offlineEdgeLambda:
path: '.build'
For usage with serverless-webpack
and serverless-bundle
the config is similar but the build path changes.
plugins:
- serverless-webpack # or serverless-bundle
custom:
offlineEdgeLambda:
path: './.webpack/service/'
Hot reload for serverless-esbuild and serverless-plugin-typescript are available with extra configuration.
The watch/reload mechanism is available form serverless-webpack, but is disabled by default for esbuild and typescript.
The flag "watchReload: true" will turn on the watcher so that typescript and esbuild solutions use the watcher to hot reload the handlers. The path to the built handlers must be specified for the watcher to work correctly.
example:
custom:
offlineEdgeLambda:
path: '.esbuild/service'
watchReload: true
Additional options can be used to modify the behavior of the file watcher and debounce logic (ignoreInitial, awaitWriteFinish, interval, debounce, and any other chokidar option).
example:
custom:
offlineEdgeLambda:
path: '.dist/service'
watchReload: true
ignoreInitial: true
awaitWriteFinish: true
interval: 500,
debounce: 750
--headersFile
Default: undefined
CloudFront injects some headers into the request. You can set these by creating a JSON file and passing its path as an option.
Example:
// .cf-headers.json
{
"CloudFront-Viewer-Country": "us",
"CloudFront-Viewer-Country-Region": "tx"
}
npx serverless offline start --headersFile .cf-headers.json