Apache HttpClient custom dynamic header on every request - java

I am writing a java client for a protected api service using Apache's HttpClient. I was wondering if it is possible to add a dynamic header to each request automatically instead of having to add the header on every HttpGet or HttpPost instance. The header needs to take the request URL and the request method (GET or POST), because of this requirement I cannot just simply add it to the default request headers when building the HttpClient. Thanks

Use custom request interceptor
CloseableHttpClient client = CachingHttpClients.custom()
.addInterceptorLast((HttpRequestInterceptor) (request, context) -> {
String method = request.getRequestLine().getMethod();
String requestUri = request.getRequestLine().getUri();
request.addHeader("x-my-header", doSomethingClever(method, requestUri));
})
.build();

Related

how to create client TGT with java cxf

I'm new to the java rest CXF client. I will make various requests to a remote server, but first I need to create a Ticket Granting Ticket (TGT). I looked through various sources but I could not find a solution. The server requests that I will create a TGT are as follows:
Content-Type: text as parameter, application / x-www-form-urlencoded as value
username
password
I create TGT when I make this request with the example URL like below using Postman. (URL is example). But in the code below, I'm sending the request, but the response is null. Could you help me with the solution?
The example URL that I make a request with POST method using Postman: https://test.service.com/v1/tickets?format=text&username=user&password=pass
List<Object> providers = new ArrayList<Object>();
providers.add(new JacksonJsonProvider());
WebClient client = WebClient.create("https://test.service.com/v1/tickets?format=text&username=user&password=pass", providers);
Response response = client.getResponse();
You need to do a POST, yet you did not specify what your payload looks like?
Your RequestDTO and ResponseDTO have to have getters/setters.
An example of using JAX-RS 2.0 Client.
Client client = ClientBuilder.newBuilder().register(new JacksonJsonProvider()).build();
WebTarget target = client.target("https://test.service.com/v1/tickets");
target.queryParam("format", "text");
target.queryParam("username", "username");
target.queryParam("password", "password");
Response response = target.request().accept(MediaType.APPLICATION_FORM_URLENCODED).post(Entity.entity(yourPostDTO,
MediaType.APPLICATION_JSON));
YourResponseDTO responseDTO = response.readEntity(YourResponseDTO.class);
int status = response.getStatus();
Also something else that can help is if you copy the POST request from POSTMAN as cURL request. It might help to see the differences between your request and POSTMAN. Perhaps extra/different headers are added by postman?
Documentation: https://cxf.apache.org/docs/jax-rs-client-api.html#JAX-RSClientAPI-JAX-RS2.0andCXFspecificAPI
Similar Stackoverflow: Is there a way to configure the ClientBuilder POST request that would enable it to receive both a return code AND a JSON object?

Get all the headers for HttpPost with entity

I'm using HttpClient to send a PUT request with a body to Azure.
The body is represented by a StringEntity.
I need to add the Azure authentication signature to the request, and in order to compute it correctly I need the values of the Content-Type and Content-Length headers.
When call the setEntity() method on the HttpPost request, no headers are added to the request, but using a HTTP debugging proxy I can see that they are correctly sent with the request.
From the Apache documentation (here) I saw I could use entity.getContentLength() and entity.getContentType() to compute those, but I would prefer to extract the data directly from the HttpPost if possible.
Anyone knows a way to force the entity to add the headers to the request, before the request is executed?
This is the code I'm using
HttpPut createBlob = new HttpPut(createBlobUrl);
createBlob.addHeader("x-ms-blob-type", "BlockBlob");
createBlob.addHeader("x-ms-date", utcTime);
createBlob.addHeader("x-ms-version", "2015-04-05");
HttpEntity body = new StringEntity("test blob", "UTF-8");
createBlob.setEntity(body);
// h is missing Content-Length and Content-Type
Header[] h = createBlob.getAllHeaders();
resp = httpclient.execute(createBlob);
I found a solution for it.
Adding an interceptor to the client, I can get the complete request with all the headers just before it's executed, so I don't need to deal with special cases where the headers are added by the entity.
HttpClientBuilder builder = HttpClientBuilder.create();
builder = builder.disableContentCompression().disableConnectionState();
builder.addInterceptorLast((HttpRequestInterceptor) (request, context) -> {
try {
SignRequest(request, account, secret);
}
catch (Exception e) {
}
});
HttpClient httpclient = builder.build();
Official tutorial about interceptor can be found at this link

Extract cookies from SOAP response using AXIS2

I am consuming a third party webservice using AXIS2 stub. The primary method which I use works FINE and has below signature:
boolean isValidUser(username, password);
The webservice is supposed to return a String (token) in the response headers as cookie :- WSToken
But I cannot find ANY method to extract the headers and cookies from the response. In fact there is no HTTPResponse object to fetch the cookies !.
I have tried this code:
MessageContext context = stub._getServiceClient().getLastOperationContext().getMessageContext(WSDLConstants.MESSAGE_LABEL_IN_VALUE);
Object response = context.getProperty("response");
But it returns a null value as there is no such property in the context. The context has below properties:
transport.http.statusCode
CHARACTER_SET_ENCODING
TRANSPORT_HEADERS
org.apache.axiom.om.util.DetachableInputStream
messageType
ContentType
TRANSPORT_IN
How can I get the cookie called 'WSToken' from the response using the stub ?
The TRANSPORT_HEADERS property should give you the HTTP headers you got. You can then look for Set-Cookie headers.

Header values overwritten on redirect in HTTPClient

I'm using httpclient 4.2.5 to make http requests which have to handle redirects as well.
Here is a little example to understand the context:
A sends http request (using httpclient 4.2.5) to B
B sends 302 redirect (containing url to C) back to A
A follows redirect to C
C retrieves request URL and do some work with it
If C parses the request URL by request.getRequestURL() (HttpServlet API) it contains e.g. host and port of the original request from step 1, which is wrong.
The problem exists in step 2, where httpclient handles the redirect. It just copies all headers from the original request (step 1) to the current request (step 3). I already had a look at the responsible code, via grepcode:
DefaultRequestDirector
HttpUriRequest redirect = redirectStrategy.getRedirect(request, response, context);
HttpRequest orig = request.getOriginal();
redirect.setHeaders(orig.getAllHeaders());
I don't really understand why all headers of the original request are copied to the current request.
E.g. using cURL for a simple test is doing it as expected, C would receive the correct host and port.
Implementing my own redirect strategy does not help because the original headers are copied after it.
I had the same problem when trying to download files from bitbucket's download section using HttpClient. After the first request bitbucket sends a redirect to CDN which then complains if the Authorization header is set.
I worked around it by changing DefaultRedirectStrategy.getRedirect() method to return redirect object which does not allow Authorization headers to be set.
I work with Scala so here is the code:
val http = new DefaultHttpClient()
http.setRedirectStrategy(new DefaultRedirectStrategy() {
override def getRedirect(
request: HttpRequest, response: HttpResponse, context: HttpContext
): HttpRequestBase = {
val uri: URI = getLocationURI(request, response, context)
val method: String = request.getRequestLine.getMethod
if (method.equalsIgnoreCase(HttpHead.METHOD_NAME)) {
new HttpHead(uri) {
override def setHeaders(headers: Array[Header]) {
super.setHeaders(headers.filterNot(_.getName == "Authorization"))
}
}
}
else {
new HttpGet(uri) {
override def setHeaders(headers: Array[Header]) {
super.setHeaders(headers.filterNot(_.getName == "Authorization"))
}
}
}
}
})
Please note orig.getAllHeaders() returns an array of headers explicitly added to the message by the caller. The code from DefaultRequestDirector posted above does not copy request headers automatically generated by HttpClient such as Host, Content-Length, Transfer-Encoding and so on.
You post a wire log of the session exhibiting the problem I may be able to tell why redirects do not work as expected.

Configuring Apache HttpClient to access service through proxy/load-balancer (overriding Host header)

I am having a problem getting the Apache HttpClient to connect to a service external to my virtualised development environment.
To access the internet (e.g. api.twitter.com) I need to call a local URL (e.g. api.twitter.com.dev.mycompany.net), which then forwards the request to real host.
The problem is, that to whatever request I send, I get a 404 Not Found response.
I have tried debugging it using wget, and it appears the problem is, that the destination server identifies the desired resource by using both the request URL and the hostname in the Host header. Since the hostname does not match, it is unable to locate the resource.
I have (unsuccessfully) tried to override the Host header by setting the http.virtual-host parameter on the client like this:
HttpClient client = new DefaultHttpClient();
if (envType.isWithProxy()) {
client.getParams().setParameter(ClientPNames.VIRTUAL_HOST, "api.twitter.com");
}
Technical details:
Client is used as an executor in RESTeasy to call the REST API. So "manually" setting the virtual host (as described here) is not an option.
Everything is done via HTTPS/SSL - not that I think it makes a difference.
Edit 1: Using a HttpHost instead of a String does not have the desired effect either:
HttpClient client = new DefaultHttpClient();
if (envType.isWithProxy()) {
HttpHost realHost = new HttpHost("api.twitter.com", port, scheme);
client.getParams().setParameter(ClientPNames.VIRTUAL_HOST, realHost);
}
Edit 2: Further investigation has revealed, that the parameter needs to be set on the request object. The following is the code v. 4.2-aplha1 of HttpClient setting the virtual host:
HttpRequest orig = request;
RequestWrapper origWrapper = wrapRequest(orig);
origWrapper.setParams(params);
HttpRoute origRoute = determineRoute(target, origWrapper, context);
virtualHost = (HttpHost) orig.getParams().getParameter(
ClientPNames.VIRTUAL_HOST);
paramsare the parameters passed from the client. But the value for 'virtualHost' is read from the request parameters.
So this changes the nature of the question to: How do I set the VIRTUAL_HOST property on the requests?
ClientPNames.VIRTUAL_HOST is the right parameter for overriding physical host name in HTTP requests. I would just recommend setting this parameter on the request object instead of the client object. If that does not produce the desired effect please post the complete wire / context log of the session (see logging guide for instructions) either here or to the HttpClient user list.
Follow-up
OK. Let's take a larger sledge hammer. One can override content of the Host header using an interceptor.
DefaultHttpClient client = new DefaultHttpClient();
client.addRequestInterceptor(new HttpRequestInterceptor() {
public void process(
final HttpRequest request,
final HttpContext context) throws HttpException, IOException {
request.setHeader(HTTP.TARGET_HOST, "www.whatever.com");
}
});
One can make the interceptor clever enough to override the header selectively, only for specific hosts.

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