okhttp: IllegalArgumentException for the url in the Cache Entry

The following error is one of our main crashes right now, around 25% of our crashes.

Fatal Exception: java.lang.IllegalArgumentException: Expected URL scheme 'http' or 'https' but no colon was found
       at okhttp3.HttpUrl$Builder.parse$okhttp(HttpUrl.java:1260)
       at okhttp3.HttpUrl$Companion.get(HttpUrl.java:1632)
       at okhttp3.Request$Builder.url(Request.java:184)
       at okhttp3.Cache$Entry.response(Cache.java:641)
       at okhttp3.Cache.get$okhttp(Cache.java:183)
       at okhttp3.internal.cache.CacheInterceptor.intercept(CacheInterceptor.java:47)
       at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:109)
       at okhttp3.internal.http.BridgeInterceptor.intercept(BridgeInterceptor.java:83)
       at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:109)
       at okhttp3.internal.http.RetryAndFollowUpInterceptor.intercept(RetryAndFollowUpInterceptor.java:76)
       at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:109)
       at de.stocard.dagger.ProvidedDependenciesModule$provideHttpClient$$inlined$-addInterceptor$1.intercept(ProvidedDependenciesModule.java:1083)
       at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:109)
       at okhttp3.internal.connection.RealCall.getResponseWithInterceptorChain$okhttp(RealCall.java:201)
       at okhttp3.internal.connection.RealCall$AsyncCall.run(RealCall.java:517)
       at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1167)
       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:641)
       at java.lang.Thread.run(Thread.java:919)

The same error was reported https://github.com/square/okhttp/issues/4322 and https://github.com/square/okhttp/issues/4918

I would like to reopen the discussion and maybe together we can find the root cause and a solution.

During the last week we were building a custom version based on the 4.9.0 to report the url contained in the Cache Entry. We modified the following line with the code below and we also modified the cache path directory to avoid possible old corrupted files.

throw IllegalArgumentException("Expected URL scheme 'http' or 'https' but no colon was found for the url input $input")

We are getting in that case the corrupted url stored in the cache file.

For example, with the following retrofit configuration:

val clientBuilder = OkHttpClient.Builder()

clientBuilder.protocols(listOf(Protocol.HTTP_1_1))

clientBuilder.addInterceptor { chain ->
    val originalRequest = chain.request()
    val requestWithUserAgent = originalRequest.newBuilder()
            .header("User-Agent", "Example/1.0.0 HTTPClient Android").build()
    chain.proceed(requestWithUserAgent)
}

val certificatePinner = CertificatePinner.Builder()
certificatePinner.add("*.example.com", "sha256/public-key-1")
clientBuilder.certificatePinner(certificatePinner.build())

val cacheDir = File(context.cacheDir, "new_caching_directory")
val cache = Cache(cacheDir, (16 * 1024 * 1024).toLong())
clientBuilder.cache(cache)

val okhttpClient = clientBuilder.build()

val retrofit = Retrofit.Builder()
                .baseUrl("https://www.example.com/")
                .client(okHttpClient)
                .build()

val exampleApi = retrofit.create(ExampleApi::class.java)

interface ExampleApi {
    @GET("users")
    fun getUsers(): Single<List<User>>
}

We are getting in the error stack traces the following urls:

Fatal Exception: java.lang.IllegalArgumentException: Expected URL scheme 'http' or 'https' but no colon was found for the url input 

5����e?��뷘b���@&-����1�W�ہ�n��?�!y6�j٬�6N�S��https://www.example.com/users

Fatal Exception: java.lang.IllegalArgumentException: Expected URL scheme 'http' or 'https' but no colon was found for the url input 

5T�k;=�fEr��,��k�H��2�C�A*�����s�������.�^https://www.example.com/users

Fatal Exception: java.lang.IllegalArgumentException: Expected URL scheme 'http' or 'https' but no colon was found for the url input ://www.example.com/users

The url stored in the cache file, as you can see, can contain some corrupted text or the https is removed from the url.

Could you have a look? I can also investigate further or give you more data if needed.

Regards