I am developing a web API for an application. I had got a situation where the user will send a few data to my API. After processing the data I have to forward a few data to other API.
But I don't want to concentrate on the response from the second API to where I had called.
After calling the second API I want to send my response to the user without waiting for the second API response.
Can anyone tell me how to handle this situation?
My API is written in JAVA spring boot REST, The Second API to where am calling is in PYTHON.
#Async will make it execute in a separate thread, i.e. the caller will not wait for the completion of the called method.
Limitations
it must be applied to public methods only
self-invocation – calling the async method from within the same class
– won’t work
Example:
Spring Doc, Example 1, Example 2
Related
We have an application that uses both rest API and soap API. At a time we use either of them, but the requirement is to change it when needed. So, the question is there a way to use a single API that can handle REST and SOAP requests, so that we can use either of them depending on our condition in spring boot?
I have tried to call using single rest API. My expectation is to find a mechanism that can handle both soap and rest requests.
which is better alternative for calling REST endpoint in springboot application, calling REST endpoints using WebClient or calling REST endpoints using RestTemplate ?
Spring’s documentation recommends using WebClient, but that’s only a valid recommendation for reactive apps. If you aren’t writing a reactive app, use OpenFeign instead. Like anything else in software, it fits well for some cases, but might complicate things for others. Choosing WebClient to implement the REST endpoint calls is strongly coupled to making your app reactive
RestTemplate gives many advantages if you are using it from within Springboot application, i.e. in your server side to another part of your own app - sort of like an internal call. Because the RestTemplate "knows" all your entities and beans and so if you need to send over or receive an object which is known within your springboot application RestTemplate can map them automatically which is a very nice advantage. If you sending a request to some third party api and do not pass or receive your known entities RestTemplate is still a valid option but it just becomes just another Http client. Its just simply there as part of Springboot provided tools. But in this case you may use any other client as well.
I have a spring application. It exposes an endpoint, which when hit, needs to make an call to some other API. So, where should I make this API call, inside my controller itself or should I do it in the service class?
Based on any Architectural style (DDD, Microservices, etc), we should follow separation of concerns.
Best practice would be to create a Rest Client class for the API you want to consume and make all rest calls inside that.
Then you create a Service class to call the method consuming the API, performing the operation, data filter, anything you want to do with data.
Next would be to inject your service class inside the controller and return the data you just consumed and did some operation on it.
It might not sound well in a small project/feature, but it is the best practice when things get complicated and grow.
I have an application which looks like this
Now, whenever a request is received at the gateway, Zuul filter AuthorizationInterceptor gets invoked which does authentication/authorization by making some calls with User Service. If the authorization succeeds then actual microservice is called.
Now the with the new requirement, I need to write some aggregated API which takes data from two services and combine the data. So I added #RestController on Gateway Proxy but before that rest controller gets invoked AuthorizationInterceptor is not getting invoked. How can I tell ZuulFilter to get invoked even when the request is locally served.
Is there any solution for this? Should this be architected in a different way?
I don't think it's a good idea to put this kind of logic into the gateway service.
What you are referring to is an aggregator service which can be after the gateway as the other two services but instead of storing data or doing some business logic, it just takes the data from the two other services and aggregates them. This way the AuthorizationInterceptor will be invoked on the gateway level as well.
Another hacky approach would be to create a custom ZuulFilter which handles an imaginary endpoint call and aggregates the data. This way your AuthorizationInterceptor will be called as well but it's not a good idea to put this kind of logic into your edge service.
My application exposes a RESTful API which when called calls out to a mailbox server and fetches data. I want to be able disable the service during application runtime in the event of some outage on the mailbox server. I wanted to do this in a way that the logic of deciding whether or not to call the mailbox server was abstracted from the actual code that calls the mailbox server. Two options which seem to fit this scenario are filters and interceptors however I'm looking for advice on which one best suits this requirement and what are the difference between each?
Thanks
If you are using Spring MVC then you can use an interceptor, which is like a filter but that has access to the Spring context. If you are using Jersey then you can't use interceptors.