无服务器框架：在 serverless.yml 中为 HTTP API 网关路由配置预先存在的 lambda 身份验证器

Question

I would like to add a preexisting lambda authenticator to the routes of a preexisting http api gateway using the serverless framework. I have followed the docs, whereby I have specified the authorizer details under provider.httpApi (lines 15 to 18), and I have referenced the authorizer on the route(s) below (line 27 & 28). Though I get the error message:

Cannot setup authorizers for externally configured HTTP API

What am I doing wrong here? It must be for a HTTP API gateway and not a REST API gateway as thats what the current infra is configured as. Thanks

Answer 1

It looks like you're using an externally configured HTTP API (I'm guessing from the id being set). In such a situation, you cannot configure authorizers in this manner, you can only do so when you're provisioning HTTP API as a part of your serverless service. What you can do there, is to setup a shared authorizer in a more manual way as described in docs here: https://www.serverless.com/framework/docs/providers/aws/events/http-api#shared-authorizer

Answer 2

I came across this post when researching how to use API gateway authorizers and serverless framework. I was terraforming the API gateway therefore needed to terraform the authorizer as well. When created, I stashed the authorizer ID in a parameter store entry. This is a 6 character alphanumeric value such as tw9qgj . I then referenced the parameter as follows:

custom:
  authorizerId: ${ssm:api_gateway_authoriser}

Then added the following block to each API eg

      - httpApi:
          path: /protected
          method: get
          authorizer:
            id: ${self:custom.authorizerId}