Develop Reference

How to use Apache Olingo behind a proxy

I can successfully reach following OData-service using different browsers and also using Postman even so I am behind a proxy:
String SERVICE_ROOT = http://services.odata.org/V4/TripPinService/
However, using Apache Olingo in Java I am not able to access this service.
JVM parameters like -Dhttp.proxySet=true -Dhttp.proxyHost=http-proxy.example.com -Dhttp.proxyPort=8080 allow me to perform basic URL functions, like retrieving HTTP status codes (google returns 200). Nevertheless, access of the OData-Service using an ODataClient is not possible (code below). No errors are thrown.
ODataClient client = ODataClientFactory.getClient();
ODataServiceDocumentRequest request = client.getRetrieveRequestFactory().getServiceDocumentRequest(SERVICE_ROOT);
ODataRetrieveResponse<ClientServiceDocument> response = request.execute();
I tried using the proxy capabilities within Olingo, however without any success:
client.getConfiguration().setHttpClientFactory(new ProxyWrappingHttpClientFactory(URI.create("http://http-proxy.example.com:8080")));
What am I doing wrong, what options do I have left?
Thank you very much.

If you are behind an NTLM proxy you can try with NTLMAuthHttpClientFactory.
NTLMAuthHttpClientFactory ntlm = new NTLMAuthHttpClientFactory(username, password, workstation, domain);
client.getConfiguration().setHttpClientFactory(ntlm);
In case that doesn't work, you can try with cntlm. Install it, change username, password, domain and proxy in C:\Program Files (x86)\Cntlm\cntlm.ini and then invoke net start cntlm.
Use this for Olingo:
client.getConfiguration().setHttpClientFactory(new ProxyWrappingHttpClientFactory(URI.create("http://localhost:3128")));

URI uri;
String scheme = "http";
try {
uri = new URI (scheme,null,host,port,null,null,null);
} catch (URISyntaxException e) {
throw(e);
}
HttpClientFactory clientProxy = new ProxyWrappingHttpClientFactory(uri,userName,password );
client.getConfiguration().setHttpClientFactory(clientProxy);

I somehow solved the problem by myself. Within VM arguments I now only have
-Djava.net.preferIPv4Stack=true
Further I defined a proxy config only within the application:
client = ODataClientFactory.getClient();
client.getConfiguration().setHttpClientFactory(
new ProxyWrappingHttpClientFactory(URI.create("http-prox.example.com:8080")));
This worked for me. :)

Sending POST data to REST service with authentication

I want to send JSON data to a REST service which includes authentication, but when I try to run this code, it throws a RuntimeException and HTTP code 302. But the link is working fine through a REST client. I think my code is unable to provide the authentication details to the link.
I have tried so many combinations, but it's still not working. Can anyone suggest where I am going wrong?
JSONObject obj=new JSONObject(req); //JSON Object
ClientConfig clientConfig = new DefaultClientConfig();
clientConfig.getFeatures().put(JSONConfiguration.FEATURE_POJO_MAPPING,
Boolean.TRUE);
Client client = Client.create(clientConfig);
//Authentication filter
client.addFilter(new HTTPBasicAuthFilter("username", "password"));
WebResource webResource = client.resource(
"http://licruleswb-dev.cloudapps.cisco.com/LicenseRules/rest/invokeRule");
ClientResponse response = webResource.accept("application/json").type(
MediaType.APPLICATION_JSON_TYPE).post(ClientResponse.class, obj.toString());
if (response.getStatus() != 200) {
throw new RuntimeException("Failed : HTTP error code : " + response.getStatus());
}
This is the error:
ERROR:Exception in thread "main" java.lang.RuntimeException: Failed :
HTTP error code : 302
at Test2.main(Test2.java:64)
Test2 is my class.

What framework are you using? Jersey? You can try setting the basic auth with:
Authenticator.setDefault(new Authenticator() {
protected PasswordAuthentication getPasswordAuthentication() {
return new PasswordAuthentication("username", "password".toCharArray());
}
});

It seems that you use Jersey REST client. You need to be aware that this approach is deprecated in version 2.5 and removed in version 2.6. In higher versions of Jersey, you need to use this:
// Send with all calls
HttpAuthenticationFeature feature = HttpAuthenticationFeature.basic(
"username", "password");
or
// Send with a single call
Response response = client.target("http://...").request()
.property(HTTP_AUTHENTICATION_BASIC_USERNAME, "username")
.property(HTTP_AUTHENTICATION_BASIC_PASSWORD, "password").get();
See this link for more details: https://jersey.java.net/documentation/latest/client.html#d0e5181.
You could enable traces in your application or use an external HTTP proxy (like tcpmon) to see the actual sent request (if there is a header Authorization with content).
Hope it helps you,
Thierry

Java SOAP web service over SSL with basic authentication, connection refused

I am trying to send a SOAP request over SSL with my own little Java client and it fails with "java.net.ConnectException: Connection refused". The same request sent with SOAPUI does not fail, I get a valid response from the server.
This is the code I am trying to run:
public static void main(String[] args) throws MalformedURLException {
System.setProperty("sun.security.ssl.allowUnsafeRenegotiation", "true");
SSLUtilities.trustAllHttpsCertificates();
URL wsdlURL = new URL(MY_WSDL_LOCATION);
QName serviceName = new QName(MY_QNAME, NAME_OF_SERVICE);
Service service = Service.create(wsdlURL, serviceName);
Order myOrder = service.getPort(Order.class);
BindingProvider portBP = (BindingProvider) myOrder;
String urlUsed = (String) portBP.getRequestContext().
get(BindingProvider.ENDPOINT_ADDRESS_PROPERTY);
System.out.println("Using URL: " + urlUsed);
((BindingProvider)myOrder).getRequestContext().put(
BindingProvider.USERNAME_PROPERTY, CORRECT_USERNAME);
((BindingProvider)myOrder).getRequestContext().put(
BindingProvider.PASSWORD_PROPERTY, CORRECT_PASSWORD);
AliveRequest aliveRequest = new AliveRequest();
MerchantInfo merchInfo = new MerchantInfo();
merchInfo.setMerchantId(CORRECT_MERCHANT_ID);
aliveRequest.setMerchantInfo(merchInfo);
AliveResponse aliveResponse = myOrder.alive(aliveRequest);
}
It fails with "java.net.ConnectException: Connection refused" exception. When I build a request from the same WSDL using SOAPUI, populate the same fields with same values and enter the same basic authentication credentials, a valid response is returned.

The problem was the fact that my Java client didn't send the request through the proxy, so my own company's firewall was blocking it. Unlike my own Java client, SOAPUI actually detects the proxy settings of the system (probably reads system environment variables) when SOAPUI's proxy settings are set "auto" (default). The solution was to set the following system properties:
-Dhttps.proxySet=true
-Dhttps.proxyHost=MY_PROXY_HOST
-Dhttps.proxyPort=MY_PROXY_PORT

JAVA - Using httpclient to post a file to google apps via http proxy (squid) gets stuck when calling execute

Context
I have a desktop JAVA application I use to upload files (blobs) to a google app blobstore.
Everything works fine with a direct connection to the Internet but it doesn't when connecting through an HTTP proxy (Squid) with authentication.
I am using httpClient 4.2.3 and I don't get any error or response. It just gets stuck when calling httpClient.execute(post).
Code
I added these lines to handle the proxy authentication and it works well when using URL to get a page:
System.setProperty("http.proxyUser", username);
System.setProperty("http.proxyPassword", password);
I tried those as well:
Authenticator.setDefault(
new Authenticator() {
#Override
public PasswordAuthentication getPasswordAuthentication() {
return new PasswordAuthentication(
username, password.toCharArray());
}
}
);
And from now on this is the same code that works when not using a proxy.
First of all I download a page where I get the url to use to post a file to the blobstore:
URL url = new URL("http://www.example.com/get-upload-url.jsp");
String urlWhereToPost=IOUtils.toString(url.openStream());
DefaultHttpClient client = new DefaultHttpClient ();
Here we prepare the multipart post:
HttpPost post
= new HttpPost( urlWhereToPost.trim() );
MultipartEntity entity
= new MultipartEntity( HttpMultipartMode.BROWSER_COMPATIBLE);
entity.addPart( "key"
, new FileBody(new File(jpgFilePath)
, "image/jpeg" )
);
post.setEntity((HttpEntity)entity);
And it is when calling execute that nothing happens (and it never get's to the next instruction):
HttpResponse execute = client.execute( post );
Tests
I have been trying several things but nothing worked:
In the beginning I thought the problem was using POST because GET works fine using URL()
but I tried using HttpClient to execute a GET and it gets stuck as well.
I used Wireshark to check the packets send to the proxy and I saw that when using URL() Wireshark recognizes the calls to the proxy as requests to execute a GET from the proxy. But when using httpClient it looks like the request is not well built because Wireshark shows a packet but doesn't recognize the inner request.
Then I tried building the POST using HttpURLConnection and it gets through the proxy and I get the answer from the server but it looks like I am not building it well because appengine doesn't find the file I send (but this would be another question...).
Conclusion
Anyone with the same problem? Any idea?

Your proxy settings are for the Java system classes. Apache HttpClient is supposed to be configured in a different way.
This link may help: Proxy authentication

Solr - instantiate HttpSolrServer with Httpclient

I need to connect to our solr server which is behind a proxy(?).
Following I tried (nothing special):
SolrServer server = new HttpSolrServer("https://urltosolr/solr");
try {
SolrPingResponse pingResponse = server.ping();
} catch (SolrServerException e) {
....
}
stacktrace:
org.apache.solr.client.solrj.SolrServerException: IOException occured when talking to server at: https://urltosolr/solr
...
Caused by: javax.net.ssl.SSLPeerUnverifiedException: peer not authenticated
After that I tried the other constructor for HttpSolrServer but I don't know how to set username and password correctly into HttpClient. Can anyone help?

I don't see where you're trying to connect through a proxy in your code, you only provided the solr url while creating the HttpSolrServer. You can provide your own HttpClient instance while creating your HttpSolrServer instance. Your HttpClient instance can contain the information about the proxy. The needed code should be the following, which you can find in the http-components examples:
DefaultHttpClient httpclient = new DefaultHttpClient();
HttpHost proxy = new HttpHost(proxyHost, proxyPort, "http");
httpclient.getParams().setParameter(ConnRoutePNames.DEFAULT_PROXY, proxy);
httpclient.getCredentialsProvider().setCredentials(
AuthScope.ANY,
new UsernamePasswordCredentials(username, password));
SolrServer solrServer = new HttpSolrServer(solrUrl, httpclient);
Looking more at your question, I don't think you need to connect using a proxy. You error is about https. Have a look at this other question and answers to see what you need to do. The version of httpclient you need to look at is 4.x.