* limitations under the License.
* ========================LICENSE_END===================================
*/
+
package org.oransc.policyagent.clients;
-import org.springframework.http.HttpStatus;
+import io.netty.channel.ChannelOption;
+import io.netty.handler.ssl.SslContext;
+import io.netty.handler.ssl.SslContextBuilder;
+import io.netty.handler.ssl.util.InsecureTrustManagerFactory;
+import io.netty.handler.timeout.ReadTimeoutHandler;
+import io.netty.handler.timeout.WriteTimeoutHandler;
+
+import java.lang.invoke.MethodHandles;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import javax.net.ssl.SSLException;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
+import org.springframework.http.client.reactive.ReactorClientHttpConnector;
+import org.springframework.lang.Nullable;
import org.springframework.web.reactive.function.client.WebClient;
+import org.springframework.web.reactive.function.client.WebClient.RequestHeadersSpec;
+import org.springframework.web.reactive.function.client.WebClientResponseException;
+
import reactor.core.publisher.Mono;
+import reactor.netty.http.client.HttpClient;
+import reactor.netty.tcp.TcpClient;
+/**
+ * Generic reactive REST client.
+ */
public class AsyncRestClient {
- private final WebClient client;
+ private static final Logger logger = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass());
+ private WebClient webClient = null;
+ private final String baseUrl;
+ private static final AtomicInteger sequenceNumber = new AtomicInteger();
- private static class AsyncRestClientException extends Exception {
+ public AsyncRestClient(String baseUrl) {
+ this.baseUrl = baseUrl;
+ }
- private static final long serialVersionUID = 1L;
+ public Mono<ResponseEntity<String>> postForEntity(String uri, @Nullable String body) {
+ Object traceTag = createTraceTag();
+ logger.debug("{} POST uri = '{}{}''", traceTag, baseUrl, uri);
+ logger.trace("{} POST body: {}", traceTag, body);
+ Mono<String> bodyProducer = body != null ? Mono.just(body) : Mono.empty();
+ return getWebClient() //
+ .flatMap(client -> {
+ RequestHeadersSpec<?> request = client.post() //
+ .uri(uri) //
+ .contentType(MediaType.APPLICATION_JSON) //
+ .body(bodyProducer, String.class);
+ return retrieve(traceTag, request);
+ });
+ }
- public AsyncRestClientException(String message) {
- super(message);
- }
+ public Mono<String> post(String uri, @Nullable String body) {
+ return postForEntity(uri, body) //
+ .flatMap(this::toBody);
}
- public AsyncRestClient(String baseUrl) {
- this.client = WebClient.create(baseUrl);
+ public Mono<String> postWithAuthHeader(String uri, String body, String username, String password) {
+ Object traceTag = createTraceTag();
+ logger.debug("{} POST (auth) uri = '{}{}''", traceTag, baseUrl, uri);
+ logger.trace("{} POST body: {}", traceTag, body);
+ return getWebClient() //
+ .flatMap(client -> {
+ RequestHeadersSpec<?> request = client.post() //
+ .uri(uri) //
+ .headers(headers -> headers.setBasicAuth(username, password)) //
+ .contentType(MediaType.APPLICATION_JSON) //
+ .bodyValue(body);
+ return retrieve(traceTag, request) //
+ .flatMap(this::toBody);
+ });
+ }
+
+ public Mono<ResponseEntity<String>> putForEntity(String uri, String body) {
+ Object traceTag = createTraceTag();
+ logger.debug("{} PUT uri = '{}{}''", traceTag, baseUrl, uri);
+ logger.trace("{} PUT body: {}", traceTag, body);
+ return getWebClient() //
+ .flatMap(client -> {
+ RequestHeadersSpec<?> request = client.put() //
+ .uri(uri) //
+ .contentType(MediaType.APPLICATION_JSON) //
+ .bodyValue(body);
+ return retrieve(traceTag, request);
+ });
+ }
+
+ public Mono<ResponseEntity<String>> putForEntity(String uri) {
+ Object traceTag = createTraceTag();
+ logger.debug("{} PUT uri = '{}{}''", traceTag, baseUrl, uri);
+ logger.trace("{} PUT body: <empty>", traceTag);
+ return getWebClient() //
+ .flatMap(client -> {
+ RequestHeadersSpec<?> request = client.put() //
+ .uri(uri);
+ return retrieve(traceTag, request);
+ });
}
public Mono<String> put(String uri, String body) {
- return client.put() //
- .uri(uri) //
- .contentType(MediaType.APPLICATION_JSON) //
- .syncBody(body) //
- .retrieve() //
- .onStatus(HttpStatus::isError,
- response -> Mono.error(new AsyncRestClientException(response.statusCode().toString()))) //
- .bodyToMono(String.class);
+ return putForEntity(uri, body) //
+ .flatMap(this::toBody);
+ }
+
+ public Mono<ResponseEntity<String>> getForEntity(String uri) {
+ Object traceTag = createTraceTag();
+ logger.debug("{} GET uri = '{}{}''", traceTag, baseUrl, uri);
+ return getWebClient() //
+ .flatMap(client -> {
+ RequestHeadersSpec<?> request = client.get().uri(uri);
+ return retrieve(traceTag, request);
+ });
}
public Mono<String> get(String uri) {
- return client.get() //
- .uri(uri) //
- .retrieve() //
- .onStatus(HttpStatus::isError,
- response -> Mono.error(new AsyncRestClientException(response.statusCode().toString()))) //
- .bodyToMono(String.class);
+ return getForEntity(uri) //
+ .flatMap(this::toBody);
+ }
+
+ public Mono<ResponseEntity<String>> deleteForEntity(String uri) {
+ Object traceTag = createTraceTag();
+ logger.debug("{} DELETE uri = '{}{}''", traceTag, baseUrl, uri);
+ return getWebClient() //
+ .flatMap(client -> {
+ RequestHeadersSpec<?> request = client.delete().uri(uri);
+ return retrieve(traceTag, request);
+ });
}
public Mono<String> delete(String uri) {
- return client.delete() //
- .uri(uri) //
- .retrieve() //
- .onStatus(HttpStatus::isError,
- response -> Mono.error(new AsyncRestClientException(response.statusCode().toString()))) //
- .bodyToMono(String.class);
+ return deleteForEntity(uri) //
+ .flatMap(this::toBody);
}
+
+ private Mono<ResponseEntity<String>> retrieve(Object traceTag, RequestHeadersSpec<?> request) {
+ return request.retrieve() //
+ .toEntity(String.class) //
+ .doOnNext(entity -> logger.trace("{} Received: {}", traceTag, entity.getBody()))
+ .doOnError(throwable -> onHttpError(traceTag, throwable));
+ }
+
+ private static Object createTraceTag() {
+ return sequenceNumber.incrementAndGet();
+ }
+
+ private void onHttpError(Object traceTag, Throwable t) {
+ if (t instanceof WebClientResponseException) {
+ WebClientResponseException exception = (WebClientResponseException) t;
+ logger.debug("{} HTTP error status = '{}', body '{}'", traceTag, exception.getStatusCode(),
+ exception.getResponseBodyAsString());
+ } else {
+ logger.debug("{} HTTP error: {}", traceTag, t.getMessage());
+ }
+ }
+
+ private Mono<String> toBody(ResponseEntity<String> entity) {
+ if (entity.getBody() == null) {
+ return Mono.just("");
+ } else {
+ return Mono.just(entity.getBody());
+ }
+ }
+
+ private static SslContext createSslContext() throws SSLException {
+ return SslContextBuilder.forClient() //
+ .trustManager(InsecureTrustManagerFactory.INSTANCE) //
+ .build();
+ }
+
+ private static WebClient createWebClient(String baseUrl, SslContext sslContext) {
+ TcpClient tcpClient = TcpClient.create() //
+ .option(ChannelOption.CONNECT_TIMEOUT_MILLIS, 10_000) //
+ .secure(c -> c.sslContext(sslContext)) //
+ .doOnConnected(connection -> {
+ connection.addHandlerLast(new ReadTimeoutHandler(30));
+ connection.addHandlerLast(new WriteTimeoutHandler(30));
+ });
+ HttpClient httpClient = HttpClient.from(tcpClient);
+ ReactorClientHttpConnector connector = new ReactorClientHttpConnector(httpClient);
+
+ return WebClient.builder() //
+ .clientConnector(connector) //
+ .baseUrl(baseUrl) //
+ .build();
+ }
+
+ private Mono<WebClient> getWebClient() {
+ if (this.webClient == null) {
+ try {
+ SslContext sslContext = createSslContext();
+ this.webClient = createWebClient(this.baseUrl, sslContext);
+ } catch (SSLException e) {
+ logger.error("Could not create WebClient {}", e.getMessage());
+ return Mono.error(e);
+ }
+ }
+ return Mono.just(this.webClient);
+ }
+
}