Two parallel and two sequential requests using Rxjava2

Question

I am trying to authorize in two services in parallel, but each of them has two steps:

The first service

1) Log in account if the user exist (else create account)

2) Create account if the user doesn't

 Maybe<String> login()
 Maybe<String> create()

The second service has the same steps.

 Maybe<Result> login2()
 Maybe<Result> create2()

I know that i can use ZIP operator for parallel requests, but i can't understand how to do all this scheme. What is the right way? I am using RxJava2 + Retrofit2.

John O'Reilly · Accepted Answer · 2017-11-10 14:50:33Z

1

You should be able to use something like following for the login/create sequencing:

Maybe.concat(login, create).firstElement();

(and can then use zip, as you mentioned, to parallelize doing this for the 2 services)

The following is a good article that covers both these patterns https://medium.com/devnibbles/rxjava-the-first-3-patterns-4c112a85b689

answered Nov 10, 2017 at 14:50

John O'Reilly

10.4k6 gold badges45 silver badges67 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Delphian Over a year ago

John, thank you for answer and article. Now I am trying to use flatmap instead of concat, I can't understand the difference.

kingston Over a year ago

@Delphian with flatMap you will end trying to create an already created account

Collectives™ on Stack Overflow

Two parallel and two sequential requests using Rxjava2

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related