org.apache.camel.component.http.helper.HttpHelper Maven / Gradle / Ivy
/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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 org.apache.camel.component.http.helper;
import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.OutputStream;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import org.apache.camel.Exchange;
import org.apache.camel.RuntimeExchangeException;
import org.apache.camel.component.http.HttpConstants;
import org.apache.camel.component.http.HttpConverter;
import org.apache.camel.component.http.HttpEndpoint;
import org.apache.camel.component.http.HttpMethods;
import org.apache.camel.converter.IOConverter;
import org.apache.camel.converter.stream.CachedOutputStream;
import org.apache.camel.util.IOHelper;
import org.apache.camel.util.ObjectHelper;
public final class HttpHelper {
private HttpHelper() {
// Helper class
}
public static void setCharsetFromContentType(String contentType, Exchange exchange) {
if (contentType != null) {
// find the charset and set it to the Exchange
int index = contentType.indexOf("charset=");
if (index > 0) {
String charset = contentType.substring(index + 8);
exchange.setProperty(Exchange.CHARSET_NAME, IOConverter.normalizeCharset(charset));
}
}
}
/**
* Writes the given object as response body to the servlet response
*
* The content type will be set to {@link HttpConstants#CONTENT_TYPE_JAVA_SERIALIZED_OBJECT}
*
* @param response servlet response
* @param target object to write
* @throws IOException is thrown if error writing
*/
public static void writeObjectToServletResponse(ServletResponse response, Object target) throws IOException {
response.setContentType(HttpConstants.CONTENT_TYPE_JAVA_SERIALIZED_OBJECT);
writeObjectToStream(response.getOutputStream(), target);
}
/**
* Writes the given object as response body to the output stream
*
* @param stream output stream
* @param target object to write
* @throws IOException is thrown if error writing
*/
public static void writeObjectToStream(OutputStream stream, Object target) throws IOException {
ObjectOutputStream oos = new ObjectOutputStream(stream);
oos.writeObject(target);
oos.flush();
IOHelper.close(oos);
}
/**
* Deserializes the input stream to a Java object
*
* @param is input stream for the Java object
* @return the java object, or null if input stream was null
* @throws ClassNotFoundException is thrown if class not found
* @throws IOException can be thrown
*/
public static Object deserializeJavaObjectFromStream(InputStream is) throws ClassNotFoundException, IOException {
if (is == null) {
return null;
}
Object answer = null;
ObjectInputStream ois = new ObjectInputStream(is);
try {
answer = ois.readObject();
} finally {
IOHelper.close(ois);
}
return answer;
}
/**
* Reads the response body from the given http servlet request.
*
* @param request http servlet request
* @param exchange the exchange
* @return the response body, can be null if no body
* @throws IOException is thrown if error reading response body
*/
public static Object readResponseBodyFromServletRequest(HttpServletRequest request, Exchange exchange) throws IOException {
InputStream is = HttpConverter.toInputStream(request, exchange);
return readResponseBodyFromInputStream(is, exchange);
}
/**
* Reads the response body from the given input stream.
*
* @param is the input stream
* @param exchange the exchange
* @return the response body, can be null if no body
* @throws IOException is thrown if error reading response body
*/
public static Object readResponseBodyFromInputStream(InputStream is, Exchange exchange) throws IOException {
if (is == null) {
return null;
}
// convert the input stream to StreamCache if the stream cache is not disabled
if (exchange.getProperty(Exchange.DISABLE_HTTP_STREAM_CACHE, Boolean.FALSE, Boolean.class)) {
return is;
} else {
CachedOutputStream cos = new CachedOutputStream(exchange);
IOHelper.copyAndCloseInput(is, cos);
return cos.getStreamCache();
}
}
/**
* Creates the URL to invoke.
*
* @param exchange the exchange
* @param endpoint the endpoint
* @return the URL to invoke
*/
public static String createURL(Exchange exchange, HttpEndpoint endpoint) {
String uri = null;
if (!(endpoint.isBridgeEndpoint())) {
uri = exchange.getIn().getHeader(Exchange.HTTP_URI, String.class);
}
if (uri == null) {
uri = endpoint.getHttpUri().toASCIIString();
}
// resolve placeholders in uri
try {
uri = exchange.getContext().resolvePropertyPlaceholders(uri);
} catch (Exception e) {
throw new RuntimeExchangeException("Cannot resolve property placeholders with uri: " + uri, exchange, e);
}
// append HTTP_PATH to HTTP_URI if it is provided in the header
String path = exchange.getIn().getHeader(Exchange.HTTP_PATH, String.class);
if (path != null) {
if (path.startsWith("/")) {
URI baseURI;
String baseURIString = exchange.getIn().getHeader(Exchange.HTTP_BASE_URI, String.class);
try {
if (baseURIString == null) {
if (exchange.getFromEndpoint() != null) {
baseURIString = exchange.getFromEndpoint().getEndpointUri();
} else {
// will set a default one for it
baseURIString = "/";
}
}
baseURI = new URI(baseURIString);
String basePath = baseURI.getRawPath();
if (path.startsWith(basePath)) {
path = path.substring(basePath.length());
if (path.startsWith("/")) {
path = path.substring(1);
}
} else {
throw new RuntimeExchangeException("Cannot analyze the Exchange.HTTP_PATH header, due to: cannot find the right HTTP_BASE_URI", exchange);
}
} catch (Throwable t) {
throw new RuntimeExchangeException("Cannot analyze the Exchange.HTTP_PATH header, due to: " + t.getMessage(), exchange, t);
}
}
if (path.length() > 0) {
// make sure that there is exactly one "/" between HTTP_URI and
// HTTP_PATH
if (!uri.endsWith("/")) {
uri = uri + "/";
}
uri = uri.concat(path);
}
}
return uri;
}
/**
* Creates the HttpMethod to use to call the remote server, often either its GET or POST.
*
* @param exchange the exchange
* @return the created method
* @throws URISyntaxException
*/
public static HttpMethods createMethod(Exchange exchange, HttpEndpoint endpoint, boolean hasPayload) throws URISyntaxException {
// is a query string provided in the endpoint URI or in a header (header
// overrules endpoint)
String queryString = exchange.getIn().getHeader(Exchange.HTTP_QUERY, String.class);
// We need also check the HTTP_URI header query part
String uriString = exchange.getIn().getHeader(Exchange.HTTP_URI, String.class);
// resolve placeholders in uriString
try {
uriString = exchange.getContext().resolvePropertyPlaceholders(uriString);
} catch (Exception e) {
throw new RuntimeExchangeException("Cannot resolve property placeholders with uri: " + uriString, exchange, e);
}
if (uriString != null) {
URI uri = new URI(uriString);
queryString = uri.getQuery();
}
if (queryString == null) {
queryString = endpoint.getHttpUri().getQuery();
}
// compute what method to use either GET or POST
HttpMethods answer;
HttpMethods m = exchange.getIn().getHeader(Exchange.HTTP_METHOD, HttpMethods.class);
if (m != null) {
// always use what end-user provides in a header
answer = m;
} else if (queryString != null) {
// if a query string is provided then use GET
answer = HttpMethods.GET;
} else {
// fallback to POST if we have payload, otherwise GET
answer = hasPayload ? HttpMethods.POST : HttpMethods.GET;
}
return answer;
}
/**
* Appends the key/value to the headers.
*
* This implementation supports keys with multiple values. In such situations the value
* will be a {@link java.util.List} that contains the multiple values.
*
* @param headers headers
* @param key the key
* @param value the value
*/
@SuppressWarnings("unchecked")
public static void appendHeader(Map headers, String key, Object value) {
if (headers.containsKey(key)) {
Object existing = headers.get(key);
List list;
if (existing instanceof List) {
list = (List) existing;
} else {
list = new ArrayList();
list.add(existing);
}
list.add(value);
value = list;
}
headers.put(key, value);
}
/**
* Extracts the parameter value.
*
* This implementation supports HTTP multi value parameters which
* is based on the syntax of [value1, value2, value3] by returning
* a {@link List} containing the values.
*
* If the value is not a HTTP mulit value the value is returned as is.
*
* @param value the parameter value
* @return the extracted parameter value, see more details in javadoc.
*/
@SuppressWarnings("unchecked")
public static Object extractHttpParameterValue(String value) {
if (value == null || ObjectHelper.isEmpty(value)) {
return value;
}
// trim value before checking for multiple parameters
String trimmed = value.trim();
if (trimmed.startsWith("[") && trimmed.endsWith("]")) {
// remove the [ ] markers
trimmed = trimmed.substring(1, trimmed.length() - 1);
List list = new ArrayList();
String[] values = trimmed.split(",");
for (String s : values) {
list.add(s.trim());
}
return list;
}
return value;
}
}
© 2015 - 2025 Weber Informatics LLC | Privacy Policy