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本文主要研究一下webflux的WebFluxTagsProvider

WebFluxTagsProvider

spring-boot-actuator-2.1.5.RELEASE-sources.jar!/org/springframework/boot/actuate/metrics/web/reactive/server/WebFluxTagsProvider.java

@FunctionalInterface
public interface WebFluxTagsProvider {

	/**
	 * Provides tags to be associated with metrics for the given {@code exchange}.
	 * @param exchange the exchange
	 * @param ex the current exception (may be {@code null})
	 * @return tags to associate with metrics for the request and response exchange
	 */
	Iterable<Tag> httpRequestTags(ServerWebExchange exchange, Throwable ex);

}
 

• WebFluxTagsProvider介面定義了httpRequestTags方法

DefaultWebFluxTagsProvider

spring-boot-actuator-2.1.5.RELEASE-sources.jar!/org/springframework/boot/actuate/metrics/web/reactive/server/DefaultWebFluxTagsProvider.java

public class DefaultWebFluxTagsProvider implements WebFluxTagsProvider {

	@Override
	public Iterable<Tag> httpRequestTags(ServerWebExchange exchange,
			Throwable exception) {
		return Arrays.asList(WebFluxTags.method(exchange), WebFluxTags.uri(exchange),
				WebFluxTags.exception(exception), WebFluxTags.status(exchange),
				WebFluxTags.outcome(exchange));
	}

}
 

• DefaultWebFluxTagsProvider實現了WebFluxTagsProvider介面，它返回了method、uri、exception、status、outcome這幾個tag

WebFluxTags

spring-boot-actuator-2.1.5.RELEASE-sources.jar!/org/springframework/boot/actuate/metrics/web/reactive/server/WebFluxTags.java

public final class WebFluxTags {

	private static final Tag URI_NOT_FOUND = Tag.of("uri", "NOT_FOUND");

	private static final Tag URI_REDIRECTION = Tag.of("uri", "REDIRECTION");

	private static final Tag URI_ROOT = Tag.of("uri", "root");

	private static final Tag URI_UNKNOWN = Tag.of("uri", "UNKNOWN");

	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() {
	}

	public static Tag method(ServerWebExchange exchange) {
		return Tag.of("method", exchange.getRequest().getMethodValue());
	}

	public static Tag status(ServerWebExchange exchange) {
		HttpStatus status = exchange.getResponse().getStatusCode();
		if (status == null) {
			status = HttpStatus.OK;
		}
		return Tag.of("status", String.valueOf(status.value()));
	}

	public static Tag uri(ServerWebExchange exchange) {
		PathPattern pathPattern = exchange
				.getAttribute(HandlerMapping.BEST_MATCHING_PATTERN_ATTRIBUTE);
		if (pathPattern != null) {
			return Tag.of("uri", pathPattern.getPatternString());
		}
		HttpStatus status = exchange.getResponse().getStatusCode();
		if (status != null) {
			if (status.is3xxRedirection()) {
				return URI_REDIRECTION;
			}
			if (status == HttpStatus.NOT_FOUND) {
				return URI_NOT_FOUND;
			}
		}
		String path = getPathInfo(exchange);
		if (path.isEmpty()) {
			return URI_ROOT;
		}
		return URI_UNKNOWN;
	}

	private static String getPathInfo(ServerWebExchange exchange) {
		String path = exchange.getRequest().getPath().value();
		String uri = StringUtils.hasText(path) ? path : "/";
		return uri.replaceAll("//+", "/").replaceAll("/$", "");
	}

	public static Tag exception(Throwable exception) {
		if (exception != null) {
			String simpleName = exception.getClass().getSimpleName();
			return Tag.of("exception", StringUtils.hasText(simpleName) ? simpleName
					: exception.getClass().getName());
		}
		return EXCEPTION_NONE;
	}

	public static Tag outcome(ServerWebExchange exchange) {
		HttpStatus status = exchange.getResponse().getStatusCode();
		if (status != null) {
			if (status.is1xxInformational()) {
				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;
	}

}
 

• WebFluxTags定義了URI_NOT_FOUND、URI_REDIRECTION、URI_ROOT、URI_UNKNOWN、EXCEPTION_NONE、OUTCOME_UNKNOWN、OUTCOME_INFORMATIONAL、OUTCOME_SUCCESS、OUTCOME_REDIRECTION、OUTCOME_CLIENT_ERROR、OUTCOME_SERVER_ERROR這些Tag常量

小結

WebFluxTagsProvider介面定義了httpRequestTags方法；DefaultWebFluxTagsProvider實現了WebFluxTagsProvider介面，它返回了method、uri、exception、status、outcome這幾個tag；WebFluxTags定義了URI_NOT_FOUND、URI_REDIRECTION、URI_ROOT、URI_UNKNOWN、EXCEPTION_NONE、OUTCOME_UNKNOWN、OUTCOME_INFORMATIONAL、OUTCOME_SUCCESS、OUTCOME_REDIRECTION、OUTCOME_CLIENT_ERROR、OUTCOME_SERVER_ERROR這些Tag常量

doc

• WebFluxTa