I am trying to pass query string through my WebSocket connections by wss://connection_url?queryparam=param
but the lambda function invoked by the connection is not able to read the query param. in fact I printed the integration response received to lambda function and it doesn't show any query param in it. should I need to configure in API gateway to allow query string params please help
Yes, enable Use Lambda Proxy integration. See https://docs.aws.amazon.com/apigateway/latest/developerguide/set-up-lambda-proxy-integrations.html
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I am using AWS API Gateway with HTTP API which invokes a lambda function. However HTTP API doesn't include USAGE feature. According to my requirement I need to create a usage for a client depending on the status code of the response sent back by the lambda. Since I cant access the response sent by lambda in API Gateway, I am looking for an custom solution. I am planing to use STEP function.
For example:
Instead of API Gateway directly invoking a lambda function it can call a STEP function where I can execute LambdaA. next it would trigger LambdaB with response from LambdaA as input to LambdaB in a sequential manner. I don't know If this is the right approach
I would like to know what is best way of solving this problem...thanks in advance
Use Case: I need to perform an API request mapping that requires data from DynamoDB.
Desired Solution: I'd like to do this using API Gateway features if possible, which would look something like this:
An external REST API request is received by API Gateway
A Proxy Resource extracts a parameter, say accountId, from the HTTP path
A Service Integration (GetItem) reads a set of values from DynamoDB using the accountId key
The values read from the DB are input to a Request Mapper VTL template
The transformed API request is then sent to an HTTP Integration endpoint
Questions:
Is that possible to do using API Gateway out-of-the-box or is that sequence too advanced?
If it's not possible, then is a lambda the best option to do most of this work (read DB, transform request, route HTTP)?
Thanks for your help!
API Gateway will not make DB queries for you. Routing this through a Lambda function is the best option here.
I would like to proxy the incoming requests to different endpoints based on a request header received in the request.
In AWS API gateway, I can set up different endpoints as separate stage variables but at integration >> Endpoint URL setting, I would like to pick the stage variable based on the value of request header value.
For example:
if header value is brand-id: abc then request should be proxied to abc.test.com
if header value is brand-id: pqr then request should be proxied to pqr.test.com
I'm expecting something like this in "Endpoint URL" value:
http://${stageVariables.${method.request.header.brand-id}}/
Any help to achieve this would be appreciated.
AFAIK this is not possible on the API Gateway level. Option is to do the mapping on the lambda integration level.
You can use Lambda Proxy Integration to achieve the similar behavior:
Create your required set of API's.
Create a proxy endpoint that will pass everything to the Lambda Function.
Inside the Lambda Function decide on the basis of headers to call the respective endpoints and pass the required data from the payload you got.
Return the response as it is from the API you called.
You can use python's adapter pattern, or string parameter formatting to save yourself from the clutter of if and else conditions. You can also consider calling Lambdas directly from your proxy Lambda with RequestResponse invoke, that may save yourself some time caused by the extra layer of API Gateway.
Im assuming lambda is like the missing piece of the puzzle for a complete api request. So you create the apigateway and then write the lambda function which bridges the gap between taking a request and returning the output of the lambda function as the http response.
I've successfully followed guides on how to set up an API gateway that triggers AWS lambda to do something, but I still don't really understand what is being done.
How is the function def handler(event, context): being called by the aws apigateway? How does it get triggered and how is the output of handler sent back?
You do not need a Lambda "in the middle". Using Lambda Proxy integration in the API Gateway you can receive the full information about the request (endpoint URL, query parameters, etc) in your targeted Lambda event.
Have a look at the following Tutorial how to setup Lambda Proxy integration with API Gateway.
The tricky thing you should care about is the structure of the response that you will return from your lambda_handler. See the requirements here.
Answering the question of "how this happens"... In short, when an HTTP request comes to your API endpoint it is automatically routed to the mapped Lambda function. Behind the scenes a new container for the Function is spawned and your request comes to the event of the lambda_handler. API Gateway by default also creates a CloudFront distribution in front of itself to serve your requests more efficiently. Once your Lambda returns the response, API Gateway parses it and constructs the HTTP response out of it. The nice thing is that all of this is managed by AWS.
I am creating an AWS ApiGateway & it invoking a lambda function asynchronously. Once apigateway sent the message lambda it'll send a 200 response with empty response. I need to send some static information with in the response message.
{
"code":"SUCCESS",
"description":"Successfully sent to lambda"
}
I tried to set up a model. But there I'm unable to set static values. Please help on this ?
You need to configure AWS API Gateway Integration Response Data Mapping return the response message from your Lambda function. If you use Lambda proxy, you can directly send the entire response including headers.
Note: If its only a static response, you don't need Lambda, you can use a Mock Endpoint with static message response.