Provide a public API for determining a request's outcome

Closes gh-18150

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/http/Outcome.java

@@ -0,0 +1,97 @@
+/*
+ * Copyright 2012-2019 the original author or authors.
+ *
+ * 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
+ *
+ *      https://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.
+ */
+
+package org.springframework.boot.actuate.metrics.http;
+
+import io.micrometer.core.instrument.Tag;
+
+/**
+ * The outcome of an HTTP request.
+ *
+ * @author Andy Wilkinson
+ * @since 2.2.0
+ */
+public enum Outcome {
+
+	/**
+	 * Outcome of the request was informational.
+	 */
+	INFORMATIONAL,
+
+	/**
+	 * Outcome of the request was success.
+	 */
+	SUCCESS,
+
+	/**
+	 * Outcome of the request was redirection.
+	 */
+	REDIRECTION,
+
+	/**
+	 * Outcome of the request was client error.
+	 */
+	CLIENT_ERROR,
+
+	/**
+	 * Outcome of the request was server error.
+	 */
+	SERVER_ERROR,
+
+	/**
+	 * Outcome of the request was unknown.
+	 */
+	UNKNOWN;
+
+	private final Tag tag;
+
+	Outcome() {
+		this.tag = Tag.of("outcome", name());
+	}
+
+	/**
+	 * Returns the {@code Outcome} as a {@link Tag} named {@code outcome}.
+	 * @return the {@code outcome} {@code Tag}
+	 */
+	public Tag asTag() {
+		return this.tag;
+	}
+
+	/**
+	 * Return the @code Outcome} for the given HTTP {@code status} code.
+	 * @param status the HTTP status code
+	 * @return the matching Outcome
+	 */
+	public static Outcome forStatus(int status) {
+		if (status >= 100 && status < 200) {
+			return INFORMATIONAL;
+		}
+		else if (status >= 200 && status < 300) {
+			return SUCCESS;
+		}
+		else if (status >= 300 && status < 400) {
+			return REDIRECTION;
+		}
+		else if (status >= 400 && status < 500) {
+			return CLIENT_ERROR;
+		}
+		else if (status >= 500 && status < 600) {
+			return SERVER_ERROR;
+		}
+		return UNKNOWN;
+	}
+
+}

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/http/package-info.java

@@ -0,0 +1,20 @@
+/*
+ * Copyright 2012-2019 the original author or authors.
+ *
+ * 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
+ *
+ *      https://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.
+ */
+
+/**
+ * Support classes HTTP-related metrics.
+ */
+package org.springframework.boot.actuate.metrics.http;

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/web/client/RestTemplateExchangeTags.java

@@ -18,15 +18,12 @@ package org.springframework.boot.actuate.metrics.web.client;
 
 import java.io.IOException;
 import java.net.URI;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.Map;
 import java.util.regex.Pattern;
 
 import io.micrometer.core.instrument.Tag;
 
+import org.springframework.boot.actuate.metrics.http.Outcome;
 import org.springframework.http.HttpRequest;
-import org.springframework.http.HttpStatus;
 import org.springframework.http.client.ClientHttpResponse;
 import org.springframework.util.StringUtils;
 import org.springframework.web.client.RestTemplate;
@@ -45,30 +42,6 @@ public final class RestTemplateExchangeTags {
 
 	private static final Pattern STRIP_URI_PATTERN = Pattern.compile("^https?://[^/]+/");
 
-	private static final Tag OUTCOME_UNKNOWN = Tag.of("outcome", "UNKNOWN");
-
-	private static final Tag OUTCOME_INFORMATIONAL = Tag.of("outcome", "INFORMATIONAL");
-
-	private static final Tag OUTCOME_SUCCESS = Tag.of("outcome", "SUCCESS");
-
-	private static final Tag OUTCOME_REDIRECTION = Tag.of("outcome", "REDIRECTION");
-
-	private static final Tag OUTCOME_CLIENT_ERROR = Tag.of("outcome", "CLIENT_ERROR");
-
-	private static final Tag OUTCOME_SERVER_ERROR = Tag.of("outcome", "SERVER_ERROR");
-
-	private static final Map<HttpStatus.Series, Tag> SERIES_OUTCOMES;
-
-	static {
-		Map<HttpStatus.Series, Tag> seriesOutcomes = new HashMap<>();
-		seriesOutcomes.put(HttpStatus.Series.INFORMATIONAL, OUTCOME_INFORMATIONAL);
-		seriesOutcomes.put(HttpStatus.Series.SUCCESSFUL, OUTCOME_SUCCESS);
-		seriesOutcomes.put(HttpStatus.Series.REDIRECTION, OUTCOME_REDIRECTION);
-		seriesOutcomes.put(HttpStatus.Series.CLIENT_ERROR, OUTCOME_CLIENT_ERROR);
-		seriesOutcomes.put(HttpStatus.Series.SERVER_ERROR, OUTCOME_SERVER_ERROR);
-		SERIES_OUTCOMES = Collections.unmodifiableMap(seriesOutcomes);
-	}
-
 	private RestTemplateExchangeTags() {
 	}
 
@@ -155,16 +128,13 @@ public final class RestTemplateExchangeTags {
 	public static Tag outcome(ClientHttpResponse response) {
 		try {
 			if (response != null) {
-				HttpStatus.Series series = HttpStatus.Series.resolve(response.getRawStatusCode());
+				return Outcome.forStatus(response.getRawStatusCode()).asTag();
-				if (series != null) {
-					return SERIES_OUTCOMES.getOrDefault(series, OUTCOME_UNKNOWN);
 			}
 		}
-		}
+		catch (IOException ex) {
-		catch (IOException | IllegalArgumentException ex) {
 			// Continue
 		}
-		return OUTCOME_UNKNOWN;
+		return Outcome.UNKNOWN.asTag();
 	}
 
 }

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/web/reactive/client/WebClientExchangeTags.java

@@ -17,15 +17,11 @@
 package org.springframework.boot.actuate.metrics.web.reactive.client;
 
 import java.io.IOException;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.Map;
 import java.util.regex.Pattern;
 
 import io.micrometer.core.instrument.Tag;
 
-import org.springframework.http.HttpStatus;
+import org.springframework.boot.actuate.metrics.http.Outcome;
-import org.springframework.http.HttpStatus.Series;
 import org.springframework.http.client.reactive.ClientHttpRequest;
 import org.springframework.web.reactive.function.client.ClientRequest;
 import org.springframework.web.reactive.function.client.ClientResponse;
@@ -51,30 +47,6 @@ public final class WebClientExchangeTags {
 
 	private static final Tag CLIENT_NAME_NONE = Tag.of("clientName", "none");
 
-	private static final Tag OUTCOME_UNKNOWN = Tag.of("outcome", "UNKNOWN");
-
-	private static final Tag OUTCOME_INFORMATIONAL = Tag.of("outcome", "INFORMATIONAL");
-
-	private static final Tag OUTCOME_SUCCESS = Tag.of("outcome", "SUCCESS");
-
-	private static final Tag OUTCOME_REDIRECTION = Tag.of("outcome", "REDIRECTION");
-
-	private static final Tag OUTCOME_CLIENT_ERROR = Tag.of("outcome", "CLIENT_ERROR");
-
-	private static final Tag OUTCOME_SERVER_ERROR = Tag.of("outcome", "SERVER_ERROR");
-
-	private static final Map<Series, Tag> SERIES_OUTCOMES;
-
-	static {
-		Map<Series, Tag> seriesOutcomes = new HashMap<>();
-		seriesOutcomes.put(Series.INFORMATIONAL, OUTCOME_INFORMATIONAL);
-		seriesOutcomes.put(Series.SUCCESSFUL, OUTCOME_SUCCESS);
-		seriesOutcomes.put(Series.REDIRECTION, OUTCOME_REDIRECTION);
-		seriesOutcomes.put(Series.CLIENT_ERROR, OUTCOME_CLIENT_ERROR);
-		seriesOutcomes.put(Series.SERVER_ERROR, OUTCOME_SERVER_ERROR);
-		SERIES_OUTCOMES = Collections.unmodifiableMap(seriesOutcomes);
-	}
-
 	private WebClientExchangeTags() {
 	}
 
@@ -146,18 +118,8 @@ public final class WebClientExchangeTags {
 	 * @since 2.2.0
 	 */
 	public static Tag outcome(ClientResponse response) {
-		try {
+		Outcome outcome = (response != null) ? Outcome.forStatus(response.rawStatusCode()) : Outcome.UNKNOWN;
-			if (response != null) {
+		return outcome.asTag();
-				Series series = HttpStatus.Series.resolve(response.rawStatusCode());
-				if (series != null) {
-					return SERIES_OUTCOMES.getOrDefault(series, OUTCOME_UNKNOWN);
-				}
-			}
-		}
-		catch (IllegalArgumentException ex) {
-			// Continue
-		}
-		return OUTCOME_UNKNOWN;
 	}
 
 }

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/web/reactive/server/WebFluxTags.java

@@ -18,6 +18,7 @@ package org.springframework.boot.actuate.metrics.web.reactive.server;
 
 import io.micrometer.core.instrument.Tag;
 
+import org.springframework.boot.actuate.metrics.http.Outcome;
 import org.springframework.http.HttpStatus;
 import org.springframework.util.StringUtils;
 import org.springframework.web.reactive.HandlerMapping;
@@ -45,18 +46,6 @@ public final class WebFluxTags {
 
 	private static final Tag EXCEPTION_NONE = Tag.of("exception", "None");
 
-	private static final Tag OUTCOME_UNKNOWN = Tag.of("outcome", "UNKNOWN");
-
-	private static final Tag OUTCOME_INFORMATIONAL = Tag.of("outcome", "INFORMATIONAL");
-
-	private static final Tag OUTCOME_SUCCESS = Tag.of("outcome", "SUCCESS");
-
-	private static final Tag OUTCOME_REDIRECTION = Tag.of("outcome", "REDIRECTION");
-
-	private static final Tag OUTCOME_CLIENT_ERROR = Tag.of("outcome", "CLIENT_ERROR");
-
-	private static final Tag OUTCOME_SERVER_ERROR = Tag.of("outcome", "SERVER_ERROR");
-
 	private WebFluxTags() {
 	}
 
@@ -145,22 +134,8 @@ public final class WebFluxTags {
 	 */
 	public static Tag outcome(ServerWebExchange exchange) {
 		HttpStatus status = exchange.getResponse().getStatusCode();
-		if (status != null) {
+		Outcome outcome = (status != null) ? Outcome.forStatus(status.value()) : Outcome.UNKNOWN;
-			if (status.is1xxInformational()) {
+		return outcome.asTag();
-				return OUTCOME_INFORMATIONAL;
-			}
-			if (status.is2xxSuccessful()) {
-				return OUTCOME_SUCCESS;
-			}
-			if (status.is3xxRedirection()) {
-				return OUTCOME_REDIRECTION;
-			}
-			if (status.is4xxClientError()) {
-				return OUTCOME_CLIENT_ERROR;
-			}
-			return OUTCOME_SERVER_ERROR;
-		}
-		return OUTCOME_UNKNOWN;
 	}
 
 }

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/web/servlet/WebMvcTags.java

@@ -23,6 +23,7 @@ import javax.servlet.http.HttpServletResponse;
 
 import io.micrometer.core.instrument.Tag;
 
+import org.springframework.boot.actuate.metrics.http.Outcome;
 import org.springframework.http.HttpStatus;
 import org.springframework.util.StringUtils;
 import org.springframework.web.servlet.HandlerMapping;
@@ -54,18 +55,6 @@ public final class WebMvcTags {
 
 	private static final Tag STATUS_UNKNOWN = Tag.of("status", "UNKNOWN");
 
-	private static final Tag OUTCOME_UNKNOWN = Tag.of("outcome", "UNKNOWN");
-
-	private static final Tag OUTCOME_INFORMATIONAL = Tag.of("outcome", "INFORMATIONAL");
-
-	private static final Tag OUTCOME_SUCCESS = Tag.of("outcome", "SUCCESS");
-
-	private static final Tag OUTCOME_REDIRECTION = Tag.of("outcome", "REDIRECTION");
-
-	private static final Tag OUTCOME_CLIENT_ERROR = Tag.of("outcome", "CLIENT_ERROR");
-
-	private static final Tag OUTCOME_SERVER_ERROR = Tag.of("outcome", "SERVER_ERROR");
-
 	private static final Tag METHOD_UNKNOWN = Tag.of("method", "UNKNOWN");
 
 	private static final Pattern TRAILING_SLASH_PATTERN = Pattern.compile("/$");
@@ -174,24 +163,8 @@ public final class WebMvcTags {
 	 * @since 2.1.0
 	 */
 	public static Tag outcome(HttpServletResponse response) {
-		if (response != null) {
+		Outcome outcome = (response != null) ? Outcome.forStatus(response.getStatus()) : Outcome.UNKNOWN;
-			HttpStatus.Series series = HttpStatus.Series.resolve(response.getStatus());
+		return outcome.asTag();
-			if (series != null) {
-				switch (series) {
-				case INFORMATIONAL:
-					return OUTCOME_INFORMATIONAL;
-				case SUCCESSFUL:
-					return OUTCOME_SUCCESS;
-				case REDIRECTION:
-					return OUTCOME_REDIRECTION;
-				case CLIENT_ERROR:
-					return OUTCOME_CLIENT_ERROR;
-				case SERVER_ERROR:
-					return OUTCOME_SERVER_ERROR;
-				}
-			}
-		}
-		return OUTCOME_UNKNOWN;
 	}
 
 }

spring-boot-project/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/http/OutcomeTests.java

@@ -0,0 +1,75 @@
+/*
+ * Copyright 2012-2019 the original author or authors.
+ *
+ * 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
+ *
+ *      https://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.
+ */
+
+package org.springframework.boot.actuate.metrics.http;
+
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link Outcome}.
+ *
+ * @author Andy Wilkinson
+ */
+public class OutcomeTests {
+
+	@Test
+	void outcomeForInformationalStatusIsInformational() {
+		for (int status = 100; status < 200; status++) {
+			assertThat(Outcome.forStatus(status)).isEqualTo(Outcome.INFORMATIONAL);
+		}
+	}
+
+	@Test
+	void outcomeForSuccessStatusIsSuccess() {
+		for (int status = 200; status < 300; status++) {
+			assertThat(Outcome.forStatus(status)).isEqualTo(Outcome.SUCCESS);
+		}
+	}
+
+	@Test
+	void outcomeForRedirectionStatusIsRedirection() {
+		for (int status = 300; status < 400; status++) {
+			assertThat(Outcome.forStatus(status)).isEqualTo(Outcome.REDIRECTION);
+		}
+	}
+
+	@Test
+	void outcomeForClientErrorStatusIsClientError() {
+		for (int status = 400; status < 500; status++) {
+			assertThat(Outcome.forStatus(status)).isEqualTo(Outcome.CLIENT_ERROR);
+		}
+	}
+
+	@Test
+	void outcomeForServerErrorStatusIsServerError() {
+		for (int status = 500; status < 600; status++) {
+			assertThat(Outcome.forStatus(status)).isEqualTo(Outcome.SERVER_ERROR);
+		}
+	}
+
+	@Test
+	void outcomeForStatusBelowLowestKnownSeriesIsUnknown() {
+		assertThat(Outcome.forStatus(99)).isEqualTo(Outcome.UNKNOWN);
+	}
+
+	@Test
+	void outcomeForStatusAboveHighestKnownSeriesIsUnknown() {
+		assertThat(Outcome.forStatus(600)).isEqualTo(Outcome.UNKNOWN);
+	}
+
+}

spring-boot-project/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/web/client/RestTemplateExchangeTagsTests.java

@@ -86,14 +86,6 @@ class RestTemplateExchangeTagsTests {
 		assertThat(tag.getValue()).isEqualTo("UNKNOWN");
 	}
 
-	@Test
-	void outcomeTagIsUnknownForCustomResponseStatus() throws Exception {
-		ClientHttpResponse response = mock(ClientHttpResponse.class);
-		given(response.getRawStatusCode()).willThrow(IllegalArgumentException.class);
-		Tag tag = RestTemplateExchangeTags.outcome(response);
-		assertThat(tag.getValue()).isEqualTo("UNKNOWN");
-	}
-
 	@Test
 	void outcomeTagIsClientErrorWhenResponseIsNonStandardInClientSeries() throws IOException {
 		ClientHttpResponse response = mock(ClientHttpResponse.class);