topic Re: How can I use REST web application as standalone server? in Alfresco Archive

How can I use REST web application as standalone server?

goto_tony — Fri, 14 Sep 2012 04:08:37 GMT

Dear all: Hi. The activiti REST web application is appreciated as a standalone process middleware server so I don't need to couple too many codes for Activiti engine. And since I am using Microsoft .net to develop application so that I can't use activiti API. By adapting RESTful api, it seems f

Re: How can I use REST web application as standalone server?

jbarrez — Fri, 14 Sep 2012 06:36:00 GMT

The Activiti REST API uses basic authentication (http://en.wikipedia.org/wiki/Basic_access_authentication),
so it's just a matter of setting the 'Authorization' header and encoding the username + password with base64.

Re: How can I use REST web application as standalone server?

goto_tony — Sat, 15 Sep 2012 08:38:04 GMT

hi, jbarrez, thanks for your reply.
I've used Apache HttpClient 4.x to prepare basic authentication as below, but it doesn't work. Please kindly instruct me the reason and next step.

public static void main(String[] args) throws Exception {
        DefaultHttpClient httpclient = new DefaultHttpClient();
        try {
            httpclient.getCredentialsProvider().setCredentials(
              AuthScope.ANY,
                    new UsernamePasswordCredentials("kermit", "kermit"));

            HttpGet httpget = new HttpGet("http://localhost:8080/activiti-rest/service/process-engine");

            System.out.println("executing request" + httpget.getRequestLine());
            HttpResponse response = httpclient.execute(httpget);
            HttpEntity entity = response.getEntity();

            System.out.println("—————————————-");
            System.out.println(response.getStatusLine());
            if (entity != null) {
                System.out.println("Response content length: " + entity.getContentLength());
            }
            EntityUtils.consume(entity);
        } finally {
            // When HttpClient instance is no longer needed,
            // shut down the connection manager to ensure
            // immediate deallocation of all system resources
            httpclient.getConnectionManager().shutdown();
        }
    }

The result is always 403 code.
executing requestGET http://localhost:8080/activiti-rest/service/process-engine HTTP/1.1
—————————————-
HTTP/1.1 403 Forbidden
Response content length: 407

Re: How can I use REST web application as standalone server?

ronald_van_kuij — Sat, 15 Sep 2012 09:06:34 GMT

Reason: authentication fails
Next step: debug the http requestvand check if the credentials are acutally passed on

Re: How can I use REST web application as standalone server?

goto_tony — Sun, 16 Sep 2012 02:48:43 GMT

hi, I am sure the account/password is fine since I can use firefox REST Client with such credencial. What I got is 403 response code instead of 200 response code. It seems such HttpClient program doesn't work yet.

I've compared Http Client and Firefox according to the tomcat log console. It didn't tell me some exception happened.

Re: How can I use REST web application as standalone server?

goto_tony — Sun, 16 Sep 2012 08:36:56 GMT

Now I've learnt the reason, i.e. Activiti Basic Authentication needs "preemptive mode" for Basic Authentication.

Now I use the Httpclient as:


        DefaultHttpClient httpclient = new DefaultHttpClient();
        try {
             HttpGet httpget = new HttpGet("http://localhost:8080/activiti-rest/service/tasks?assignee=kermit");
            
            UsernamePasswordCredentials creds = new UsernamePasswordCredentials("kermit", "kermit");
            
            httpget.addHeader(new BasicScheme().authenticate(creds, httpget));
            System.out.println("executing request" + httpget.getRequestLine());
            HttpResponse response = httpclient.execute(httpget);
         …..

And the response.getStatusLine() is 200,ok.

Re: How can I use REST web application as standalone server?

jbarrez — Mon, 17 Sep 2012 15:05:12 GMT

ok, thanks for following up with the solution.