I hope you can help me on how to paginate response from Lambda Function to api gateway.
I have an api gateway as lambda function trigger.
POST request, triggers a lambda (written in Python) that performs a query to a database, transform the data and return this data back to API.
Mi API POST method integration request has following parameters:
Integration type: Lambda Function
Use Lambda Proxy integration: YES
Rest of fields as default.
I want to paginate the API response but I can't find how to do it.
My lambda returns query details to the api as a big JSON. But I want that JSON limit can be 20 items per page.
Could you please guide me on how to implement it? Thanks
Related
I want to use API Gateway to send a message to SQS which then needs to trigger Lambda. After calculations are finished within Lambda, I need to pass the results back to API Gateway. In other words, something like this:
Get request --> Gateway API --> SQS --> Lambda --> (back to the same SQS?) --> Gateway API
I have setup all the necessary permissions meaning that I can call Gateway API and send message to SQS which then sends that to Lambda (I can see in the Cloudwatch that Lambda received the message). However, I cannot get the Lambda response back to Gateway API...
Does anybody has some advice/tutorial/blog post about that? I have watched various youtube videos and searched posts on SO but didn't find solution for my problem.
AWS Lambda can handle a large number of concurrent invocations. The default is 1000 (one thousand) and can be increased via a support ticket to "Hundreds of thousands".
If you want to use SQS to smoothen intermittent request spikes, then the Lambda function invocations will be asynchronous with respect to the caller's/client's API Gateway call and you need to use other means to feedback the Lambda invocation result to the API Gateway caller/client.
One such possibility can be a callback URL that your Lambda will invoke on the caller's/client's side once it has processed the invocation. Or you can store the lambda invocation result somewhere (such as S3 or DynamoDB) and the caller/client can use polling to periodically ask for the invocation result (check whether it is ready and if so, retrieve it).
Either way, once you use SQS to decouple API Gateway invocations from the processing of those invocations by your Lambda function via SQS messages, then the processing of the Lambda invocations will be asynchronous to the API Gateway caller/client request. So, the HTTP request of the API Gateway caller/client will return right away without waiting for the Lambda invocation result.
I have a python lambda function that I want to decode and read the payload of a jwt.
I created a get method and passing the authorization bearer-token to the endpoint.
How can i pass and read the jwt using lambda function through api gateway?
You can utilise the mapping template of method integration section. The mapping template utlises velocity template for creating the event. You can capture the headers and send them in the event.
Refer https://docs.aws.amazon.com/apigateway/latest/developerguide/api-gateway-mapping-template-reference.html
After invocation of lambda function, the JWT token can be captured in the event and you can retreive the payload.
Background
I currently have an authorizer that takes a JWT token and decodes it and checks if valid or not to build a policy document, then that is used to grant or deny access to API endpoints.
Currently, the endpoints are using query strings as parameters to grab data.
Problem
I need to make it so that the values for the user and email etc are the ones that come from the decodes JWT Token. How do I pass the decodes values to the input of the other lambda functions?
I am open to suggestions, or links, or at least a point in the right direction.
Per the documentation, you need to include those in the context section of the authorizer response. Then you will need to map the context values in your API Gateway mapping template.
If you are using Lambda Proxy Integration then the context returned from the Authorizer function will be in the event.requestContext.authorizer. That does not appear to be documented anywhere, but I always recommend printing the entire event object to your logs when you first start working on a Lambda function so you can see exactly what is being passed into it.
I have an API endpoint on AWS API Gateway with AWS Lambda (Python & Flask) to store some data from a JSON file.
e.g) curl -X POST http://www.xxx.yyy/store -d #zzz.json
However, when I tried executing the API with a bigger JSON file, I encountered a timeout error. Through my investigation, the maximum timeout setting for Lambda is 300 seconds, and API Gateway is 29 seconds. The maximum timeout for Lambda 300 sec sounds fine, but 29 seconds sounds too short. What kind of things could be a solution? The JSON data can be split by id, but it needs to be sent as one file.
EDIT:
Sure I can't change the number. Any suggestion to solve this problem using another technology/system design pattern? I can't change the input, though.
EDIT2:
Currently, the Lambda function has validation based on JSON scheme, parse into models, and save into database. Any suggestions?
Is there anyway you can update your Lambda function to hand off to another process?
By decoupling you could for example do the following:
API Gateway -> Lambda (Perform any mandatory action, then store in S3 as a blob) -> S3 -> Another Lambda to process.
Uploading files with lambdas can be tricky and a direct upload is not recommended unless the file size is under the limits.
Warning currently:
API Gateway has a payload limit of 10 MB
API Gateway has Maximum timeout of 30 s
Lambda has an invocation payload (request and response) limit of 6 MB
The best approach is a basically a two step process:
The client app makes an HTTP request to the lambda to get an upload URL. The lambda returns a pre-signed POST URL to S3
The client post the file using the pre-signed URL
API Gateway limits : https://docs.aws.amazon.com/apigateway/latest/developerguide/limits.html
Lambda limits: https://docs.aws.amazon.com/lambda/latest/dg/gettingstarted-limits.html
The timeout value cannot be increased:
Resource or operation: Integration timeout
Default quota: 50 milliseconds - 29 seconds for all integration types, including
Lambda, Lambda proxy, HTTP, HTTP proxy, and AWS integrations.
Can be increased: Not for the lower or upper bounds.
Source: https://docs.aws.amazon.com/apigateway/latest/developerguide/limits.html
I want to fetch the environment details inside the lambda function such as stage parameter or api gateway url or http mehtod. My lambda function is executed through API Gateway. need help to find out the correct way to achieve this.