[http] add websocket handler tests

Introduce simple websocket handler and verify that response is received.
Use 5 seconds timeout - curl has no option to break data receiving with other methods

Author: linev

net/http/test/test_server.cxx

@@ -4,6 +4,7 @@
 #include <fstream>
 
 #include "THttpServer.h"
+#include "THttpWSHandler.h"
 #include "TROOT.h"
 
 #include "TSystem.h"
@@ -15,8 +16,52 @@
 Int_t httpport = 0;
 TString server_url;
 
+class TUserHandler : public THttpWSHandler {
+   public:
+      UInt_t fWSId{0};
+      Int_t fServCnt{0};
+
+      TUserHandler(const char *name = nullptr, const char *title = nullptr) : THttpWSHandler(name, title) {}
+
+      // load custom HTML page when open correspondent address
+      TString GetDefaultPageContent() override { return "dummy_page_content"; }
+
+      Bool_t ProcessWS(THttpCallArg *arg) override
+      {
+         if (!arg || (arg->GetWSId() == 0))
+            return kTRUE;
+
+         if (arg->IsMethod("WS_CONNECT"))
+            // accept only if connection not established
+            return fWSId == 0;
+
+         if (arg->IsMethod("WS_READY")) {
+            fWSId = arg->GetWSId();
+            return kTRUE;
+         }
+
+         if (arg->IsMethod("WS_CLOSE")) {
+            fWSId = 0;
+            return kTRUE;
+         }
+
+         if (arg->IsMethod("WS_DATA")) {
+            TString str;
+            str.Append((const char *)arg->GetPostData(), arg->GetPostDataLength());
+            if ((str == "DataRequest") && (arg->GetWSId() == fWSId))
+               SendCharStarWS(arg->GetWSId(), "DataResponse");
+            else
+               SendCharStarWS(arg->GetWSId(), "DataRejected");
+            return kTRUE;
+         }
+
+         return kFALSE;
+      }
+};
+
+
 // main http server
-std::string execute_request(const char *url, const char *post = nullptr)
+std::string execute_request(const char *url, const char *post = nullptr, Bool_t ws = kFALSE)
 {
    TString fname = TString::Format("http_server_%d.output", httpport),
            pname, exec;
@@ -25,16 +70,21 @@ std::string execute_request(const char *url, const char *post = nullptr)
       pname = TString::Format("http_server_%d.post", httpport);
       std::ofstream f(pname.Data());
       f << post;
+   }
+
+   if (post && ws)
+      exec = TString::Format("curl -sS --max-time 5 -N -T - 'ws://localhost:%d%s' < %s > %s", httpport, url, pname.Data(), fname.Data());
+   else if (post)
       exec = TString::Format("curl -sS -X POST '%s%s' --data-binary @%s -o %s", server_url.Data(), url, pname.Data(), fname.Data());
-   } else {
+   else
       exec = TString::Format("curl -sS '%s%s' -o %s", server_url.Data(), url, fname.Data());
-   }
 
    printf("Execute %s\n", exec.Data());
 
    std::string res;
 
-   if (gSystem->Exec(exec) != 0)
+   // websocket ends with timeout - ignore failure for it
+   if ((gSystem->Exec(exec) != 0) && !ws)
       res = "<fail>";
    else
       res = THttpServer::ReadFileContent(fname.Data());
@@ -56,7 +106,7 @@ TEST(THttpServer, main)
    for(int ntry = 0; ntry < 100; ++ntry) {
       Int_t port = (Int_t) (25000 + gRandom->Rndm() * 1000);
       // only two threads, bind to loopback address only
-      TString arg = TString::Format("http:%d?loopback&thrds=2", port);
+      TString arg = TString::Format("http:%d?loopback&thrds=3", port);
       if (serv.CreateEngine(arg)) {
          httpport = port;
          break;
@@ -70,9 +120,12 @@ TEST(THttpServer, main)
 
    server_url = TString::Format("http:/localhost:%d", httpport);
 
+   TUserHandler handler("ws", "Test WebSocket handler");
+
    TNamed obj1("obj1", "title1");
    TNamed obj2("obj2", "title2");
 
+   serv.Register("/", &handler);
    serv.Register("/", &obj1);
    serv.Register("/", &obj2);
 
@@ -154,4 +207,12 @@ TEST(THttpServer, main)
    EXPECT_EQ(res, "null") << "returns null when executes void method";
    EXPECT_EQ(std::string("NewTitle"), obj1.GetTitle()) << "title must match with submitted value";
    obj1.SetTitle("title1");
+
+
+   // test websocket functionality
+   res = execute_request("/ws/index.htm");
+   EXPECT_EQ(res, "dummy_page_content") << "default html page for webcosket handler";
+
+   res = execute_request("/ws/root.websocket", "DataRequest", kTRUE);
+   EXPECT_EQ(res, "DataResponse") << "check data after websocket communication";
 }