Extract Mock HTTP client requests and responses

This commit extracts Mock HTTP client request and response for the
imperative variant. These are made available in the testFixtures
configuration for shared usage.

spring-web/src/testFixtures/java/org/springframework/web/testfixture/http/client/MockClientHttpRequest.java

@@ -0,0 +1,154 @@
+/*
+ * Copyright 2002-2022 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.web.testfixture.http.client;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.net.URI;
+import java.net.URISyntaxException;
+import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
+
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
+import org.springframework.http.client.ClientHttpRequest;
+import org.springframework.http.client.ClientHttpResponse;
+import org.springframework.lang.Nullable;
+import org.springframework.util.Assert;
+import org.springframework.util.StreamUtils;
+import org.springframework.web.util.UriComponentsBuilder;
+
+/**
+ * Mock implementation of {@link ClientHttpRequest}.
+ *
+ * @author Brian Clozel
+ * @author Rossen Stoyanchev
+ */
+public class MockClientHttpRequest implements ClientHttpRequest {
+
+	private static final Charset DEFAULT_CHARSET = StandardCharsets.UTF_8;
+
+	private final HttpHeaders headers = new HttpHeaders();
+
+	private HttpMethod httpMethod;
+
+	private URI uri;
+
+	private final ByteArrayOutputStream body = new ByteArrayOutputStream(1024);
+
+	@Nullable
+	private ClientHttpResponse clientHttpResponse;
+
+	private boolean executed = false;
+
+
+	public MockClientHttpRequest() {
+		this.httpMethod = HttpMethod.GET;
+		try {
+			this.uri = new URI("/");
+		}
+		catch (URISyntaxException ex) {
+			throw new IllegalStateException(ex);
+		}
+	}
+
+	public MockClientHttpRequest(HttpMethod httpMethod, String urlTemplate, Object... vars) {
+		this.httpMethod = httpMethod;
+		this.uri = UriComponentsBuilder.fromUriString(urlTemplate).buildAndExpand(vars).encode().toUri();
+	}
+
+	@Override
+	public HttpHeaders getHeaders() {
+		return this.headers;
+	}
+
+	@Override
+	public OutputStream getBody() throws IOException {
+		return this.body;
+	}
+
+	public byte[] getBodyAsBytes() {
+		return this.body.toByteArray();
+	}
+
+	public String getBodyAsString() {
+		return getBodyAsString(DEFAULT_CHARSET);
+	}
+
+	public String getBodyAsString(Charset charset) {
+		return StreamUtils.copyToString(this.body, charset);
+	}
+
+	public void setMethod(HttpMethod httpMethod) {
+		this.httpMethod = httpMethod;
+	}
+
+	@Override
+	public HttpMethod getMethod() {
+		return this.httpMethod;
+	}
+
+	@Override
+	@Deprecated
+	public String getMethodValue() {
+		return this.httpMethod.name();
+	}
+
+	public void setURI(URI uri) {
+		this.uri = uri;
+	}
+
+	@Override
+	public URI getURI() {
+		return this.uri;
+	}
+
+	public void setResponse(ClientHttpResponse clientHttpResponse) {
+		this.clientHttpResponse = clientHttpResponse;
+	}
+
+	public boolean isExecuted() {
+		return this.executed;
+	}
+
+	@Override
+	public final ClientHttpResponse execute() throws IOException {
+		this.executed = true;
+		return executeInternal();
+	}
+
+	protected ClientHttpResponse executeInternal() throws IOException {
+		Assert.state(this.clientHttpResponse != null, "No ClientHttpResponse");
+		return this.clientHttpResponse;
+	}
+
+	@Override
+	public String toString() {
+		StringBuilder sb = new StringBuilder();
+		sb.append(this.httpMethod);
+		sb.append(' ').append(this.uri);
+		if (!getHeaders().isEmpty()) {
+			sb.append(", headers: ").append(getHeaders());
+		}
+		if (sb.length() == 0) {
+			sb.append("Not yet initialized");
+		}
+		return sb.toString();
+	}
+
+}

spring-web/src/testFixtures/java/org/springframework/web/testfixture/http/client/MockClientHttpResponse.java

@@ -0,0 +1,99 @@
+/*
+ * Copyright 2002-2022 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.web.testfixture.http.client;
+
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.charset.StandardCharsets;
+
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.client.ClientHttpResponse;
+import org.springframework.util.Assert;
+
+/**
+ * Mock implementation of {@link ClientHttpResponse}.
+ *
+ * @author Rossen Stoyanchev
+ * @author Brian Clozel
+ */
+public class MockClientHttpResponse implements ClientHttpResponse {
+
+	private final HttpHeaders headers = new HttpHeaders();
+
+	private final HttpStatus status;
+
+	private InputStream body;
+
+
+	public MockClientHttpResponse() {
+		this.status = HttpStatus.OK;
+	}
+
+	public MockClientHttpResponse(HttpStatus statusCode) {
+		Assert.notNull(statusCode, "HttpStatus is required");
+		this.status = statusCode;
+	}
+
+	@Override
+	public HttpStatus getStatusCode() throws IOException {
+		return this.status;
+	}
+
+	@Override
+	@SuppressWarnings("deprecation")
+	public int getRawStatusCode() throws IOException {
+		return this.status.value();
+	}
+
+	@Override
+	public String getStatusText() throws IOException {
+		return this.status.getReasonPhrase();
+	}
+
+	@Override
+	public HttpHeaders getHeaders() {
+		return this.headers;
+	}
+
+	@Override
+	public InputStream getBody() throws IOException {
+		return this.body;
+	}
+
+	public void setBody(byte[] body) {
+		Assert.notNull(body, "body is required");
+		this.body = new ByteArrayInputStream(body);
+	}
+
+	public void setBody(String body) {
+		Assert.notNull(body, "body is required");
+		this.body = new ByteArrayInputStream(body.getBytes(StandardCharsets.UTF_8));
+	}
+
+	@Override
+	public void close() {
+		try {
+			getBody().close();
+		}
+		catch (IOException ex) {
+			// ignore
+		}
+	}
+
+}

spring-web/src/testFixtures/java/org/springframework/web/testfixture/http/client/package-info.java

@@ -0,0 +1,9 @@
+/**
+ * Contains mock request and response types for the imperative HTTP client
+ */
+@NonNullApi
+@NonNullFields
+package org.springframework.web.testfixture.http.client;
+
+import org.springframework.lang.NonNullApi;
+import org.springframework.lang.NonNullFields;

spring-web/src/testFixtures/java/org/springframework/web/testfixture/http/client/reactive/package-info.java

@@ -0,0 +1,9 @@
+/**
+ * Contains mock request and response types for the reactive HTTP client
+ */
+@NonNullApi
+@NonNullFields
+package org.springframework.web.testfixture.http.client.reactive;
+
+import org.springframework.lang.NonNullApi;
+import org.springframework.lang.NonNullFields;