Retrofit and RxJava (Netflix Open Source Meetup S02E02)

A 5-minute lightning introduction to Retrofit, its RxJava integration, and how to use it for quick-and-easy composition of API calls.

Video: https://www.youtube.com/watch?v=aEuNBk1b5OE#t=2480

http://www.meetup.com/Netflix-Open-Source-Platform/events/184153592/

Transcript

1. Retrofit
   Jake Wharton
   

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2. Retrofit
   Example:
   GitHub API
   List Contributors
   

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3. Retrofit
   Example:
   GitHub API
   List Contributors
   GET /repos/:owner/:repo/contributors
   

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4. Retrofit
   GET /repos/:owner/:repo/contributors
   interface GitHub {
   List contributors(
   String owner,
   String repo);
   }
   

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5. Retrofit
   GET /repos/:owner/:repo/contributors
   interface GitHub {
   List contributors(
   String owner,
   String repo);
   }
   class Contributor {
   String login;
   long contributions;
   }
   

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6. Retrofit
   GET /repos/:owner/:repo/contributors
   interface GitHub {
   List contributors(
   String owner,
   String repo);
   }
   

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7. Retrofit
   GET /repos/:owner/:repo/contributors
   interface GitHub {
   @GET("/repos/{owner}/{repo}/contributors")
   List contributors(
   String owner,
   String repo);
   }
   

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8. Retrofit
   GET /repos/:owner/:repo/contributors
   interface GitHub {
   @GET("/repos/{owner}/{repo}/contributors")
   List contributors(
   @Path("owner") String owner,
   @Path("repo") String repo);
   }
   

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9. Retrofit
   RestAdapter restAdapter = new RestAdapter.Builder()
   .setEndpoint("https://api.github.com/")
   .build();
   

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10. Retrofit
    RestAdapter restAdapter = new RestAdapter.Builder()
    .setEndpoint("https://api.github.com/")
    .build();
    GitHub gitHub = restAdapter.create(GitHub.class);
    

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11. Retrofit
    RestAdapter restAdapter = new RestAdapter.Builder()
    .setEndpoint("https://api.github.com/")
    .build();
    GitHub gitHub = restAdapter.create(GitHub.class);
    List contributors =
    gitHub.contributors("netflix", "rxjava");
    

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12. Retrofit
    List contributors =
    gitHub.contributors("netflix", "rxjava");
    for (Contributor c : contributors) {
    println(c.login + '\t' + c.contributions);
    }
    

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13. Retrofit
    List contributors =
    gitHub.contributors("netflix", "rxjava");
    for (Contributor c : contributors) {
    println(c.login + '\t' + c.contributions);
    }
    1483 benjchristensen
    225 zsxwing
    167 samuelgruetter
    146 jmhofer
    137 akarnokd
    105 DavidMGross
    102 AppliedDuality
    ...
    

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14. Retrofit
    interface GitHub {
    @GET("/repos/{owner}/{repo}/contributors")
    List contributors(
    @Path("owner") String owner,
    @Path("repo") String repo);
    }
    

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15. Retrofit
    interface GitHub {
    @GET("/repos/{owner}/{repo}/contributors?anon=true")
    List contributors(
    @Path("owner") String owner,
    @Path("repo") String repo);
    }
    

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16. Retrofit
    interface GitHub {
    @GET("/repos/{owner}/{repo}/contributors")
    List contributors(
    @Path("owner") String owner,
    @Path("repo") String repo,
    @Query("anon") boolean includeAnonymous);
    }
    

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17. Retrofit
    interface GitHub {
    @POST("/repos/{owner}/{repo}/hooks")
    Response createHook(
    @Path("owner") String owner,
    @Path("repo") String repo,
    @Body Hook hook);
    }
    

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18. Retrofit
    interface GitHub {
    @POST("/repos/{owner}/{repo}/hooks")
    Response createHook(
    @Path("owner") String owner,
    @Path("repo") String repo,
    @Body Hook hook);
    }
    class Hook {
    String name;
    Map config;
    List events;
    boolean active;
    }
    

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19. Retrofit
    RestAdapter restAdapter = new RestAdapter.Builder()
    .setEndpoint("https://drive.google.com/api/")
    .setConverter(new ProtoConverter())
    .build();
    

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20. Retrofit
    RestAdapter restAdapter = new RestAdapter.Builder()
    .setEndpoint("https://drive.google.com/api/")
    .setConverter(new ProtoConverter())
    .setClient(new OkClient())
    .build();
    

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21. Retrofit
    OkHttpClient client = new OkHttpClient();
    client.setProtocols(Arrays.asList(HTTP_2));
    RestAdapter restAdapter = new RestAdapter.Builder()
    .setEndpoint("https://drive.google.com/api/")
    .setConverter(new ProtoConverter())
    .setClient(new OkClient(client))
    .build();
    

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22. Retrofit
    ● Form URL encoding
    ● Response streaming
    ● Request interceptors
    ● Dynamic headers
    ● Android
    ● Multipart
    ● Logging
    ● Mock RestAdapter
    ● Asynchronous invoke
    ● AppEngine
    ...and more!
    

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23. Retrofit + RxJava
    

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24. Retrofit + RxJava
    interface GitHub {
    @GET("/repos/{owner}/{repo}/contributors")
    List contributors(
    @Path("owner") String owner,
    @Path("repo") String repo);
    }
    

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25. Retrofit + RxJava
    interface GitHub {
    @GET("/repos/{owner}/{repo}/contributors")
    Observable> contributors(
    @Path("owner") String owner,
    @Path("repo") String repo);
    }
    

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26. Retrofit + RxJava
    gitHub.contributors("netflix", "rxjava")
    .lift(flattenList())
    .forEach(c -> println(c.login + '\t' + c.contributions));
    

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27. Retrofit + RxJava
    gitHub.contributors("netflix", "rxjava")
    .lift(flattenList())
    .forEach(c -> println(c.login + '\t' + c.contributions));
    1483 benjchristensen
    225 zsxwing
    167 samuelgruetter
    146 jmhofer
    137 akarnokd
    105 DavidMGross
    102 AppliedDuality
    ...
    

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28. Retrofit + RxJava
    interface GitHub {
    @GET("/repos/{owner}/{repo}/contributors")
    Observable> contributors(
    @Path("owner") String owner,
    @Path("repo") String repo);
    @GET("/users/{user}")
    Observable user(
    @Path("user") String user);
    }
    

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29. Retrofit + RxJava
    gitHub.contributors("netflix", "rxjava")
    .lift(flattenList())
    .flatMap(c -> gitHub.user(c.login))
    .forEach(user -> println(user.name));
    

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30. Retrofit + RxJava
    gitHub.contributors("netflix", "rxjava")
    .lift(flattenList())
    .flatMap(c -> gitHub.user(c.login))
    .forEach(user -> println(user.name));
    Ben Christensen
    Shixiong Zhu
    null
    Joachim Hofer
    null
    David Gross
    null
    ...
    

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31. Retrofit + RxJava
    gitHub.contributors("netflix", "rxjava")
    .lift(flattenList())
    .flatMap(c -> gitHub.user(c.login))
    .filter(user -> user.name != null)
    .forEach(user -> println(user.name));
    

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32. Retrofit + RxJava
    gitHub.contributors("netflix", "rxjava")
    .lift(flattenList())
    .flatMap(c -> gitHub.user(c.login))
    .filter(user -> user.name != null)
    .forEach(user -> println(user.name));
    Ben Christensen
    Shixiong Zhu
    Joachim Hofer
    David Gross
    Matthias Käppler
    Justin Ryan
    Mairbek Khadikov
    ...
    

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33. Retrofit + RxJava
    interface GitHub {
    @GET("/repos/{owner}/{repo}/contributors")
    Observable> contributors(
    @Path("owner") String owner,
    @Path("repo") String repo);
    @GET("/users/{user}/starred")
    Observable> starred(
    @Path("user") String user);
    }
    

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34. Retrofit + RxJava
    gitHub.contributors("netflix", "rxjava")
    .lift(flattenList())
    .flatMap(c -> gitHub.starred(c.login))
    .lift(flattenList())
    .groupBy(r -> r.full_name)
    .flatMap(g -> g.count().map(c -> c + "\t" + g.getKey()))
    .toSortedList((a, b) -> b.compareTo(a))
    .lift(flattenList())
    .take(8)
    .forEach(Main::println);
    

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35. Retrofit + RxJava
    7 Netflix/RxJava
    2 twitter/finagle
    2 scala/scala
    2 mbostock/d3
    2 kpelykh/docker-java
    2 Netflix/zuul
    2 Netflix/feign
    2 Netflix/archaius
    

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36. Retrofit + RxJava
    gitHub.contributors("square", "retrofit")
    .lift(flattenList())
    .flatMap(c -> gitHub.starred(c.login))
    .lift(flattenList())
    .groupBy(r -> r.full_name)
    .flatMap(g -> g.count().map(c -> c + "\t" + g.getKey()))
    .toSortedList((a, b) -> b.compareTo(a))
    .lift(flattenList())
    .take(8)
    .forEach(Main::println);
    

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37. gitHub.contributors("square", "retrofit")
    .lift(flattenList())
    .flatMap(c -> gitHub.starred(c.login))
    .lift(flattenList())
    .filter(r -> !r.full_name.startsWith("square/"))
    .groupBy(r -> r.full_name)
    .flatMap(g -> g.count().map(c -> c + "\t" + g.getKey()))
    .toSortedList((a, b) -> b.compareTo(a))
    .lift(flattenList())
    .take(8)
    .forEach(Main::println);
    Retrofit + RxJava
    

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38. Retrofit + RxJava
    4 frankiesardo/auto-parcel
    4 Comcast/FreeFlow
    3 xxv/android-lifecycle
    3 robolectric/robolectric
    3 inmite/android-butterknife-zelezny
    3 google/auto
    3 facebook/rebound
    3 etsy/AndroidStaggeredGrid
    

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39. Retrofit + RxJava
    4 frankiesardo/auto-parcel
    4 Comcast/FreeFlow
    3 xxv/android-lifecycle
    3 robolectric/robolectric
    3 inmite/android-butterknife-zelezny
    3 google/auto
    3 facebook/rebound
    3 etsy/AndroidStaggeredGrid
    3 Netflix/RxJava
    

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40. Retrofit
    square.github.io/retrofit
    

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