Functions

serverless-builder has a built-in support for common lambda functions with best practices applied by default.

HTTP

There are two ways of generating HTTP endpoint. You can use one of the helper functions e.g. http_get, http_post, or just more generic http with passed explicitly HTTP method.

from serverless.aws.functions.http import HTTPFunction

service.builder.function.http_get("test-list", "List all tests", "/")
service.builder.function.http_post("test-list", "List all tests", "/")
service.builder.function.http_put("test-list", "List all tests", "/")
service.builder.function.http_patch("test-list", "List all tests", "/")
service.builder.function.http_delete("test-list", "List all tests", "/")
service.builder.function.http_options("test-list", "List all tests", "/")
service.builder.function.http_any("test-list", "List all tests", "/")
service.builder.function.http("test", "description", "/", HTTPFunction.POST)

Call to any of the above functions will generate serverless.com function with its corresponding HTTP event e.g.:

functions:
  Test:
    name: service-name-${sls:stage}-test
    description: description
    handler: service_name.test.handler
    events:
    - http:
        path: /
        method: POST

EventBridge

service.builder.function.event_bridge(
    "event_bridge_function",
    "sample event bridge function",
    "epsy",
    {"source": ["saas.external"]},
)

With DLQ

By default function.event_bridge will setup DLQ for your lambda that processes EventBridge messages.

S3

service.builder.function.s3(
        "Reload",
        "Reloads list of IDs",
        timeout=30,
        bucket="${self:service}.${ssm:/global/primary-domain}",
        event="s3:ObjectCreated:*",
        rules=[{"prefix": "list/ids"}],
    )

Websockets

from serverless.aws.functions.websocket import WebsocketEvent, Authorizer as WebsocketEventAuthorizer


service.builder.function.websocket(
    "handler_connect",
    "Handles client opening Websocket connection",
    events=[WebsocketEvent(route="$connect", authorizer=WebsocketEventAuthorizer("HandleAuthorization"))],
    handler="my_module.handler.handle_connect",
)

Generic

service.builder.function.generic(
    "my-generic-function",
    "Handle internal calls",
    handler="my_project.my_module.handler",

    # By default every function has LogGroup created by `serverless-builder`
    # but sometimes you have to customise it, for that you can use `log_group`
    log_group=dict(
        DeletionPolicy="Retain",
        Properties=dict(
            RetentionInDays=3653,
        )
    )
)