Honor the Retry-After HTTP header in case of 413 status code.

Issue-ID: DCAEGEN2-1483
Signed-off-by: tkogut <tomasz.kogut@nokia.com>
Change-Id: I429474d4a0565f5aa9bd542daa0db814c5504ef6

2 files changed, 230 insertions, 0 deletions

diff --git a/rest-services/http-client/src/test/java/org/onap/dcaegen2/services/sdk/rest/services/adapters/http/retry/DelayExtractorTest.java b/rest-services/http-client/src/test/java/org/onap/dcaegen2/services/sdk/rest/services/adapters/http/retry/DelayExtractorTest.java
new file mode 100644
index 00000000..d5759b26
--- /dev/null
+++ b/rest-services/http-client/src/test/java/org/onap/dcaegen2/services/sdk/rest/services/adapters/http/retry/DelayExtractorTest.java
@@ -0,0 +1,98 @@
+/*
+ * ============LICENSE_START====================================
+ * DCAEGEN2-SERVICES-SDK
+ * =========================================================
+ * Copyright (C) 2021 Nokia. All rights reserved.
+ * =========================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=====================================
+ */
+
+package org.onap.dcaegen2.services.sdk.rest.services.adapters.http.retry;
+
+import io.vavr.Tuple;
+import io.vavr.collection.HashMultimap;
+import io.vavr.control.Option;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.CsvSource;
+import org.junit.jupiter.params.provider.ValueSource;
+import org.onap.dcaegen2.services.sdk.rest.services.adapters.http.HttpResponse;
+import org.onap.dcaegen2.services.sdk.rest.services.adapters.http.ImmutableHttpResponse;
+
+import java.time.Duration;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class DelayExtractorTest {
+
+    private static final HttpResponse DEFAULT = ImmutableHttpResponse.builder()
+            .url("")
+            .statusCode(0)
+            .rawBody("".getBytes())
+            .headers(HashMultimap.withSeq().empty())
+            .build();
+
+    private static final RetryIntervalExtractor DELAY_EXTRACTOR = new RetryIntervalExtractor();
+
+    @Test
+    void shouldExtractValueFromFirstValidHeaderWhenStatusCode413() {
+        // given
+        HttpResponse response = ImmutableHttpResponse.copyOf(DEFAULT)
+                .withStatusCode(413)
+                .withHeaders(HashMultimap.withSeq().ofEntries(
+                        Tuple.of("Any", "12"),
+                        Tuple.of("Retry-After", "15"),
+                        Tuple.of("Retry-After", "100")
+                ));
+
+        // when
+        Option<Duration> delay = DELAY_EXTRACTOR.extractDelay(response);
+
+        // then
+        assertThat(delay.get()).isEqualTo(Duration.ofSeconds(15));
+    }
+
+    @ParameterizedTest
+    @ValueSource(ints = {100, 200, 300, 400, 500})
+    void shouldExtractNoValueWhenStatusCodeDifferentThan413(int statusCode) {
+        // given
+        HttpResponse response = ImmutableHttpResponse.copyOf(DEFAULT)
+                .withStatusCode(statusCode);
+
+        // when
+        Option<Duration> delay = DELAY_EXTRACTOR.extractDelay(response);
+
+        // then
+        assertThat(delay).isEqualTo(Option.none());
+    }
+
+    @ParameterizedTest
+    @CsvSource({
+            "Retry-After,",
+            "Retry-After,invalid",
+            "Retry-After,999999999999",
+            "Any,12"})
+    void shouldExtractNoValueWhenStatusCode413AndNoValidHeader(String key, String value) {
+        // given
+        HttpResponse response = ImmutableHttpResponse.copyOf(DEFAULT)
+                .withStatusCode(413)
+                .withHeaders(HashMultimap.withSeq().ofEntries(Tuple.of(key, value)));
+
+        // when
+        Option<Duration> delay = DELAY_EXTRACTOR.extractDelay(response);
+
+        // then
+        assertThat(delay).isEqualTo(Option.none());
+    }
+}
diff --git a/rest-services/http-client/src/test/java/org/onap/dcaegen2/services/sdk/rest/services/adapters/http/retry/RetryLogicTest.java b/rest-services/http-client/src/test/java/org/onap/dcaegen2/services/sdk/rest/services/adapters/http/retry/RetryLogicTest.java
new file mode 100644
index 00000000..8319d3ae
--- /dev/null
+++ b/rest-services/http-client/src/test/java/org/onap/dcaegen2/services/sdk/rest/services/adapters/http/retry/RetryLogicTest.java
@@ -0,0 +1,132 @@
+/*
+ * ============LICENSE_START====================================
+ * DCAEGEN2-SERVICES-SDK
+ * =========================================================
+ * Copyright (C) 2021 Nokia. All rights reserved.
+ * =========================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=====================================
+ */
+
+package org.onap.dcaegen2.services.sdk.rest.services.adapters.http.retry;
+
+import io.netty.handler.timeout.ReadTimeoutException;
+import io.vavr.collection.HashMultimap;
+import io.vavr.collection.HashSet;
+import io.vavr.control.Option;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.onap.dcaegen2.services.sdk.rest.services.adapters.http.HttpResponse;
+import org.onap.dcaegen2.services.sdk.rest.services.adapters.http.ImmutableHttpResponse;
+import org.onap.dcaegen2.services.sdk.rest.services.adapters.http.config.ImmutableRetryConfig;
+import org.onap.dcaegen2.services.sdk.rest.services.adapters.http.config.RetryConfig;
+import org.onap.dcaegen2.services.sdk.rest.services.adapters.http.exceptions.RetryableException;
+import org.onap.dcaegen2.services.sdk.rest.services.model.logging.RequestDiagnosticContext;
+import reactor.core.publisher.Mono;
+import reactor.test.StepVerifier;
+
+import java.net.ConnectException;
+import java.time.Duration;
+
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+class RetryLogicTest {
+
+    private static final HashSet<Integer> RETRYABLE_HTTP_RESPONSE_CODES =
+            HashSet.of(404, 408, 413, 429, 500, 502, 503, 504);
+    private static final HashSet<Class<? extends Throwable>> RETRYABLE_EXCEPTIONS =
+            HashSet.of(ReadTimeoutException.class, ConnectException.class);
+    private static final Duration RETRY_INTERVAL = Duration.ofSeconds(5);
+    private static final int RETRY_COUNT = 3;
+    private static final Duration RETRY_EXHAUSTED = Duration.ofSeconds(RETRY_COUNT * RETRY_INTERVAL.getSeconds());
+    private static final RetryConfig RETRY_CONFIG = ImmutableRetryConfig.builder()
+            .retryCount(RETRY_COUNT)
+            .retryInterval(RETRY_INTERVAL)
+            .retryableHttpResponseCodes(RETRYABLE_HTTP_RESPONSE_CODES)
+            .customRetryableExceptions(RETRYABLE_EXCEPTIONS)
+            .build();
+
+    private final RequestDiagnosticContext dummyContext = mock(RequestDiagnosticContext.class);
+    private final RetryIntervalExtractor retryIntervalExtractor = mock(RetryIntervalExtractor.class);
+    private RetryLogic retryLogic;
+
+    @BeforeEach
+    void setUp() {
+        retryLogic = new RetryLogic(RETRY_CONFIG, retryIntervalExtractor);
+    }
+
+    @Test
+    void shouldRetryWhenRetryableException() {
+        // when
+        Mono<?> mono = Mono
+                .error(ReadTimeoutException.INSTANCE)
+                .retryWhen(retryLogic.retry(dummyContext));
+
+        // then
+        StepVerifier.withVirtualTime(() -> mono)
+                .expectSubscription()
+                .expectNoEvent(RETRY_EXHAUSTED)
+                .expectError(ReadTimeoutException.class)
+                .verify();
+    }
+
+    @Test
+    void shouldNotRetryWhenUnretryableException() {
+        // when
+        Mono<?> mono = Mono
+                .error(RuntimeException::new)
+                .retryWhen(retryLogic.retry(dummyContext));
+
+        // then
+        StepVerifier.withVirtualTime(() -> mono)
+                .expectSubscription()
+                .expectError(RuntimeException.class)
+                .verify();
+    }
+
+    @Test
+    void shouldUseRetryIntervalFromExtractorWhenRetryableStatusCode() {
+        // given
+        HttpResponse httpResponse = httpResponse413();
+        Duration retryInterval = Duration.ofSeconds(10);
+        when(retryIntervalExtractor.extractDelay(httpResponse))
+                .thenReturn(Option.of(retryInterval));
+
+        // when
+        Mono<?> mono = Mono
+                .error(() -> new RetryableException(httpResponse))
+                .retryWhen(retryLogic.retry(dummyContext));
+
+        // then
+        long noEvents = RETRY_COUNT * retryInterval.getSeconds();
+        StepVerifier.withVirtualTime(() -> mono)
+                .expectSubscription()
+                .expectNoEvent(Duration.ofSeconds(noEvents))
+                .expectError(RetryableException.class)
+                .verify();
+        verify(retryIntervalExtractor, times(RETRY_COUNT)).extractDelay(httpResponse);
+    }
+
+    private ImmutableHttpResponse httpResponse413() {
+        return ImmutableHttpResponse.builder()
+                .url("")
+                .statusCode(413)
+                .rawBody("".getBytes())
+                .headers(HashMultimap.withSeq().empty())
+                .build();
+    }
+
+}