Retrofit 和 Rxjava 不发送请求

Question

I'm trying to implement Retrofit with RxJava. I've got all of the components shown in every tutorial I've found on the topic, but I don't actually see a request ever started. What am I missing? Converting Retrofit to RxJava means there is no .enqueue() to call, so why isn't the request sent? The app has the internet permissions and I've tested it on both emulators and physical devices. What can I do to further debug the issue?

@GET("things/{thing}")
    fun getThing(@Path("thing") thingName: String): Observable<Thing>

private val service: ThingsService

init {
    val clientBuilder = OkHttpClient.Builder()
    clientBuilder.addInterceptor(HttpLoggingInterceptor())

    val retrofit = Retrofit.Builder()
        .baseUrl("https://example.com")
        .client(clientBuilder.build())
        .addConverterFactory(GsonConverterFactory.create())
        .addCallAdapterFactory(RxJava3CallAdapterFactory.create())
        .build()

    service = retrofit.create(ThingsService::class.java)
}

fun test(thingName) {
    val aThing = service.getThing(thingName)
        .observeOn(AndroidSchedulers.mainThread())
        .subscribe({ thing -> }, { error -> })
}

With this configuration I never see a request logged.

Answer 1

The issue of seeing absolutely no output was a combination of several problems:

1. While I tested putting a log statement in the .subscribe() block, I didn't put one in the error block.

2. The log level on the HttpLoggingInterceptor wasn't set correctly to log the type of error occurring.

3. On one of the devices (the emulator) the internet permission hadn't been granted correctly because the permission was added to the manifest file after the first install.

Solution:

Remove and reinstall the app after adding the internet permission, check for content in the error block, and be sure to set the correct log level in the interceptor:

val interceptor = HttpLoggingInterceptor().apply {
   level = HttpLoggingInterceptor.Level.BODY
}

val client = OkHttpClient.Builder().apply {
    if (BuildConfig.DEBUG) {
        addInterceptor(interceptor)
    }
}.build()