Add tests for retry logic on socket timeout and unexpected errors in ConfigFetcher

Author: novalisdenahi

src/test/java/com/configcat/ConfigCatClientTest.java

@@ -856,8 +856,6 @@ void testHooksAutoPollSub() throws IOException {
         server.enqueue(new MockResponse().setResponseCode(200).setBody(RULES_JSON));
         server.enqueue(new MockResponse().setResponseCode(500).setBody(""));
         server.enqueue(new MockResponse().setResponseCode(500).setBody(""));
-        server.enqueue(new MockResponse().setResponseCode(500).setBody(""));
-        server.enqueue(new MockResponse().setResponseCode(500).setBody(""));
 
         AtomicBoolean changed = new AtomicBoolean(false);
         AtomicReference<ClientCacheState> ready = new AtomicReference<>(null);

src/test/java/com/configcat/ConfigFetcherTest.java

@@ -366,6 +366,40 @@ public void retryOnTransientHttpError() throws Exception {
         fetcher.close();
     }
 
+    @Test
+    public void retryOnSocketTimeoutException() throws Exception {
+        this.server.enqueue(new MockResponse().setResponseCode(200).setBodyDelay(2, TimeUnit.SECONDS).setBody(TEST_JSON));
+        this.server.enqueue(new MockResponse().setResponseCode(200).setBody(TEST_JSON));
+
+        ConfigFetcher fetcher = new ConfigFetcher(new OkHttpClient.Builder().readTimeout(1, TimeUnit.SECONDS).build(), logger,
+                "", this.server.url("/").toString(), false, PollingModes.manualPoll().getPollingIdentifier());
+
+        FetchResponse response = fetcher.fetchAsync(null).get();
+
+        assertTrue(response.isFetched());
+        assertEquals("fakeValue", response.entry().getConfig().getEntries().get("fakeKey").getSettingsValue().getStringValue());
+        assertEquals(2, this.server.getRequestCount());
+
+        fetcher.close();
+    }
+
+    @Test
+    public void retryOnUnexpectedError() throws Exception {
+        this.server.enqueue(new MockResponse().setResponseCode(200).setSocketPolicy(SocketPolicy.DISCONNECT_DURING_RESPONSE_BODY).setBody(TEST_JSON));
+        this.server.enqueue(new MockResponse().setResponseCode(200).setBody(TEST_JSON));
+
+        ConfigFetcher fetcher = new ConfigFetcher(new OkHttpClient.Builder().readTimeout(1, TimeUnit.SECONDS).build(), logger,
+                "", this.server.url("/").toString(), false, PollingModes.manualPoll().getPollingIdentifier());
+
+        FetchResponse response = fetcher.fetchAsync(null).get();
+
+        assertTrue(response.isFetched());
+        assertEquals("fakeValue", response.entry().getConfig().getEntries().get("fakeKey").getSettingsValue().getStringValue());
+        assertEquals(2, this.server.getRequestCount());
+
+        fetcher.close();
+    }
+
     @Test
     public void retryOnTransientHttpErrorBothFail() throws Exception {
         // Both first request and retry return 500