AWS API Gateway Service Orchestration - amazon-web-services

Is there any way to orchestrate the micro services from API gateway? I have two micro servicess and I am tring to aggregate the data from the API gateway. Tried with STEP function but it is asynchronized in nature.
Request will come to the API gateway, we need to call multiple services and aggregate the data and send it back

You can try lambda function to aggregate different services response.

Related

How to use ECS and Lambda microservices within the same API?

I am trying to setup a microservice architecture on AWS, each microservice is a REST API.
Some of the services are running on ECS using Fargate and some of the services are running as a set of lambdas.
I am trying to have each api route resolve to the correct service, whether it is a ECS or Lambda based service.
I can see how it would be possible using only ECS services (with Application Load Balancer and listeners) or using only Lambdas (with an API Gateway). But I just cant seem to figure out how to mix the two together.
I have been searching relentlessly all week and I cannot find any decent documentation or an example of how to implement something similar to this.
There appears to be a limit to the number of routes for ALB or API Gateway. If I have several lambda based services there will need to be a declared path for each Lambda function and they will use up the path limit very quickly.
Should there be an intermediary step between each service and the API Gateway? For instance, each Lambda service has its own API Gateway which 'groups' those functions together. Which would mean there will be a nested set of API Gateways that the parent API Gateway routes to. This doesn't feel correct though.
Any help in the right direction would be appreciated.
Thanks
Your AWS account's API Gateway REST and Websocket routes/resources limit can be increased with a request to AWS support.

How to call two endpoints for a single request

We have an existing endpoint published in AWS Api Gateway POST https://publicendpoint/app/users which points to the internal endpoint https://microservice1/app/users.
As we're in the process of backend database migration, whenever https://publicendpoint/app/users is called, we need to call two endpoints
https://microservice1-olddb/app/users and
https://microservice1-newdb/app/users .
How to do this?
Have tried with creating a API Gateway trigger with lambda.
But not able to achieve this scenario with lambda trigger.
API Gateway doesn't do any orchestration, so you can't point it at both endpoints. And even if it did, how would you handle one service failing, which service takes precedence with the response given etc.
The simplest answer is probably to use a Lambda as an orchestration layer. That is point API Gateway at a Lambda which in turn calls both endpoints.

API Gateway - How Deploy API works?

After creating API Gateway with two API names and integrating with lambda function,
AWS documentation recommends to deploy this API, as shown below:
1) What does deploy API mean? How creating API gateway different from deploying API?
2) Does deploy API option internally create Cloud formation template? that creates a stack and deploy
1) What does deploy API mean? How creating an API gateway different from deploying API?
Let' say you have created your API but how about making it public so that it can be used.
That's where deploy comes. Once you are done with writing your API, deploy it to make it callable by your users. When you deploy, then you get the link from API Gateway which can be accessed by everyone.
It is described here
2) Does deploy API option internally create Cloud formation template? that creates a stack and deploy
No, Like you said you have integrated a lambda function with your API then API Gateway will simply redirect all the calls to your lambda function which is serverless.
An API Gateway is a Proxy that manages the endpoints ,It acts as the single entryway into a system allowing multiple APIs or microservices to act cohesively and provide a uniform experience to the user.
The most important role the API gateway plays is ensuring reliable processing of every API call. In addition, the API gateway provides the ability to design API specs, help provide enterprise-grade security, and manage APIs centrally.
An API Gateway is a server that is the single entry point into the
system. It is similar to the Facade pattern from object‑oriented
design. The API Gateway encapsulates the internal system architecture
and provides an API that is tailored to each client. It might have
other responsibilities such as authentication, monitoring, load
balancing, caching, request shaping and static response handling.
https://learn.microsoft.com/en-us/azure/architecture/microservices/design/gateway
https://microservices.io/patterns/apigateway.html
Deploying a REST API in Amazon API Gateway:
https://docs.aws.amazon.com/apigateway/latest/developerguide/api-gateway-tutorials.html
https://auth0.com/docs/integrations/aws-api-gateway/custom-authorizers/part-1
https://auth0.com/docs/integrations/aws-api-gateway/custom-authorizers/part-2
https://docs.aws.amazon.com/apigateway/latest/developerguide/how-to-deploy-api.html

How can i call sagemaker inference endpoint using API gateway

I am trying to call sagemaker inference endpoint from api gateway with AWS Integration.I don't want to use lamdba in between of API gateway and sagemaker runtime. I followed this doc to setup api gateway method but it fails.
How can i call sagemaker inference endpoint from API gateway?
Web Browser ----> API Gateway ----> Sagemaker endpoint
API Gateway supports integration with AWS services directly (without the Lambda). You can follow the instructions at https://docs.aws.amazon.com/apigateway/latest/developerguide/getting-started-aws-proxy.html.
When you go to Step 4 in the instructions above, for the AWS Service option, you can choose 'SageMaker Runtime' to target the invoke endpoints.
API Gateway can be used to front an Amazon SageMaker inference endpoint as a REST API, by making use of an API Gateway feature called mapping templates. This feature makes it possible for the REST API to be integrated directly with an Amazon SageMaker runtime endpoint, thereby avoiding the use of any intermediate compute resource (such as AWS Lambda or Amazon ECS containers) to invoke the endpoint. The result is a solution that is simpler, faster, and cheaper to run. See this blog post for more detail on how to configure the API Gateway mapping templates against the Sagemaker runtime endpoint.
it's a long shot since it's an old question but somebody might end up here.
Reading the first section of the documentation about calling the inference endpoint in sagemaker, you'll find that you can only call it with a POST and pass your input data in the body.
https://docs.aws.amazon.com/sagemaker/latest/APIReference/API_runtime_InvokeEndpoint.html
So it might be that you created a GET method in API Gateway and that you need to map your request parameters to a body payload or simply set up a POST method instead.

AWS API Gateway Lambda as a proxy for microservices

As my project is going to be deployed on AWS, we started thinking about AWS API Gateway as a way to have one main entry point for all of our microservices(frankly speaking, we also would like to use by some other reasons like security). I was playing with API Gateway REST API and I had feeling that it it a bit incovinient if we have to register there every REST service we have.
I found very good option of using AWS API Gateway and lambda function as a proxy. It is described here:
https://medium.com/wolox-driving-innovation/https-medium-com-wolox-driving-innovation-building-microservices-api-aws-e9a455cc3456
https://aws.amazon.com/blogs/compute/using-api-gateway-with-vpc-endpoints-via-aws-lambda
I would like to know your opinion about this approach. May be you could also share some other approaches that can simplify API Gateway configuration for REST API?
There are few considerations when you proxy your existing services through API Gateway.
If your backend is not publicly then you need to setup a VPC and a site to site VPN connection from the VPC to your backend Network and use Lambda's to proxy your services.
If you need do any data transformations or aggregations, you need to use Lambda's(Inside VPC is optional unless VPN connection is needed).
If you have complex integrations behind the API gateway for your services, you can look into having ESB or Messaging Middleware running in your on-premise or AWS then proxy to API Gateway.
You can move data model schema validations to API Gateway.
You can move service authentication to API Gateway by writing a Custom Authorizer Lambda.
If you happen to move your User pool and identity service to AWS, you can migrate to AWS Cognito Manage Service and use AWS Cognito Authorizer in API Gateway to authenticate.
For usecases when you adopt dumb pipes (as described on martinfowler.com) AWS API Gateway is a reasonable option.
For AWS API Gateway I'd suggest to describe/design your API first with RAML or OpenAPI/Swagger and then import into AWS using AWS API Importer.
As soon as you plan to move logic in there, such as dynamic routing, detailed monitoring, alerting, etc, I'd suggest considering other approaches, such as:
Apigee
Mulesoft
WSO2
You can also host them on an EC2 within your VPC or opt-in for the hosted version. (which does have a significant pricetag in some cases)
For describing APIs you can use RAML (for Mulesoft) or OpenAPI (ex-Swagger, for Apigee and WSO2). You can also convert between them using APIMATIC which enables you to migrate your specification across various API Gateways (even AWS).