com.google.appengine.repackaged.com.google.api.client.googleapis.MethodOverride Maven / Gradle / Ivy
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/*
* Copyright 2010 Google Inc.
*
* 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.
*/
package com.google.api.client.googleapis;
import com.google.api.client.http.EmptyContent;
import com.google.api.client.http.HttpExecuteInterceptor;
import com.google.api.client.http.HttpMethods;
import com.google.api.client.http.HttpRequest;
import com.google.api.client.http.HttpRequestInitializer;
import com.google.api.client.http.UrlEncodedContent;
import java.io.IOException;
/**
* Thread-safe HTTP request execute interceptor for Google API's that wraps HTTP requests inside of
* a POST request and uses {@link #HEADER} header to specify the actual HTTP method.
*
* Use this for example for an HTTP transport that doesn't support PATCH like {@code
* NetHttpTransport} or {@code UrlFetchTransport}. By default, only the methods not supported by the
* transport will be overridden. When running behind a firewall that does not support certain verbs
* like PATCH, use the {@link MethodOverride.Builder#setOverrideAllMethods(boolean)} constructor
* instead to specify to override all methods. POST is never overridden.
*
*
This class also allows GET requests with a long URL (> 2048 chars) to be instead sent using
* method override as a POST request.
*
*
Sample usage, taking advantage that this class implements {@link HttpRequestInitializer}:
*
*
{@code
* public static HttpRequestFactory createRequestFactory(HttpTransport transport) {
* return transport.createRequestFactory(new MethodOverride());
* }
* }
*
* If you have a custom request initializer, take a look at the sample usage for {@link
* HttpExecuteInterceptor}, which this class also implements.
*
* @since 1.4
* @author Yaniv Inbar
*/
public final class MethodOverride implements HttpExecuteInterceptor, HttpRequestInitializer {
/**
* Name of the method override header.
*
* @since 1.13
*/
public static final String HEADER = "X-HTTP-Method-Override";
/** Maximum supported URL length. */
static final int MAX_URL_LENGTH = 2048;
/**
* Whether to allow all methods (except GET and POST) to be overridden regardless of whether the
* transport supports them.
*/
private final boolean overrideAllMethods;
/** Only overrides HTTP methods that the HTTP transport does not support. */
public MethodOverride() {
this(false);
}
MethodOverride(boolean overrideAllMethods) {
this.overrideAllMethods = overrideAllMethods;
}
public void initialize(HttpRequest request) {
request.setInterceptor(this);
}
public void intercept(HttpRequest request) throws IOException {
if (overrideThisMethod(request)) {
String requestMethod = request.getRequestMethod();
request.setRequestMethod(HttpMethods.POST);
request.getHeaders().set(HEADER, requestMethod);
if (requestMethod.equals(HttpMethods.GET)) {
// take the URI query part and put it into the HTTP body
request.setContent(new UrlEncodedContent(request.getUrl().clone()));
// remove query parameters from URI
request.getUrl().clear();
} else if (request.getContent() == null) {
// Google servers will fail to process a POST unless the Content-Length header is specified
request.setContent(new EmptyContent());
}
}
}
private boolean overrideThisMethod(HttpRequest request) throws IOException {
String requestMethod = request.getRequestMethod();
if (requestMethod.equals(HttpMethods.POST)) {
return false;
}
if (requestMethod.equals(HttpMethods.GET)
? request.getUrl().build().length() > MAX_URL_LENGTH
: overrideAllMethods) {
return true;
}
return !request.getTransport().supportsMethod(requestMethod);
}
/**
* Builder for {@link MethodOverride}.
*
* @since 1.12
* @author Yaniv Inbar
*/
public static final class Builder {
/**
* Whether to allow all methods (except GET and POST) to be overridden regardless of whether the
* transport supports them.
*/
private boolean overrideAllMethods;
/** Builds the {@link MethodOverride}. */
public MethodOverride build() {
return new MethodOverride(overrideAllMethods);
}
/**
* Returns whether to allow all methods (except GET and POST) to be overridden regardless of
* whether the transport supports them.
*/
public boolean getOverrideAllMethods() {
return overrideAllMethods;
}
/**
* Sets whether to allow all methods (except GET and POST) to be overridden regardless of
* whether the transport supports them.
*
*
Default is {@code false}.
*/
public Builder setOverrideAllMethods(boolean overrideAllMethods) {
this.overrideAllMethods = overrideAllMethods;
return this;
}
}
}