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Reference Guide
httpcontrol.C File Reference

Detailed Description

This program demonstrates simple application control via THttpServer Two histogram are filled within endless loop.

Via published commands one can enable/disable histograms filling There are also command to clear histograms content

After macro started, open in browser with url


Histograms will be automatically displayed and monitoring with interval 2000 ms started

#include "TH1.h"
#include "TH2.h"
#include "TRandom3.h"
#include "TSystem.h"
#include "THttpServer.h"
Bool_t bFillHist = kTRUE;
void httpcontrol()
// create histograms
TH1D *hpx = new TH1D("hpx","This is the px distribution",100,-4,4);
TH2D *hpxpy = new TH2D("hpxpy","py vs px",40,-4,4,40,-4,4);
// start http server
THttpServer* serv = new THttpServer("http:8080");
// One could specify location of newer version of JSROOT
// serv->SetJSROOT("https://root.cern.ch/js/latest/");
// serv->SetJSROOT("http://jsroot.gsi.de/latest/");
// register histograms
serv->Register("/", hpx);
serv->Register("/", hpxpy);
// enable monitoring and
// specify items to draw when page is opened
// register simple start/stop commands
serv->RegisterCommand("/Start", "bFillHist=kTRUE;", "button;rootsys/icons/ed_execute.png");
serv->RegisterCommand("/Stop", "bFillHist=kFALSE;", "button;rootsys/icons/ed_interrupt.png");
// one could hide commands and let them appear only as buttons
// register commands, invoking object methods
serv->RegisterCommand("/ResetHPX","/hpx/->Reset()", "button;rootsys/icons/ed_delete.png");
serv->RegisterCommand("/ResetHPXPY","/hpxpy/->Reset()", "button;rootsys/icons/bld_delete.png");
// create debug text element, use MathJax - works only on Firefox
serv->CreateItem("/Debug","debug output");
serv->SetItemField("/Debug", "_kind", "Text");
serv->SetItemField("/Debug", "value","\\(\\displaystyle{x+1\\over y-1}\\)");
serv->SetItemField("/Debug", "mathjax", "true");
// Fill histograms randomly
TRandom3 random;
Float_t px, py;
const Long_t kUPDATE = 1000;
Long_t cnt = 0;
while (kTRUE) {
if (bFillHist) {
} else {
gSystem->Sleep(10); // sleep minimal time
if ((cnt % kUPDATE==0) || !bFillHist) {
// IMPORTANT: one should regularly call ProcessEvents
// to let http server process requests
serv->SetItemField("/Debug", "value", Form("\\(\\displaystyle{x+1\\over y-1}\\) Loop:%ld", cnt/kUPDATE));
if (gSystem->ProcessEvents()) break;
bool Bool_t
Definition: RtypesCore.h:63
long Long_t
Definition: RtypesCore.h:54
float Float_t
Definition: RtypesCore.h:57
const Bool_t kTRUE
Definition: RtypesCore.h:100
char * Form(const char *fmt,...)
Formats a string in a circular formatting buffer.
Definition: TString.cxx:2452
R__EXTERN TSystem * gSystem
Definition: TSystem.h:559
virtual void SetFillColor(Color_t fcolor)
Set the fill area color.
Definition: TAttFill.h:37
1-D histogram with a double per channel (see TH1 documentation)}
Definition: TH1.h:617
virtual void SetDirectory(TDirectory *dir)
By default, when a histogram is created, it is added to the list of histogram objects in the current ...
Definition: TH1.cxx:8804
virtual Int_t Fill(Double_t x)
Increment bin with abscissa X by 1.
Definition: TH1.cxx:3338
2-D histogram with a double per channel (see TH1 documentation)}
Definition: TH2.h:300
Int_t Fill(Double_t) override
Invalid Fill method.
Definition: TH2.cxx:347
Online http server for arbitrary ROOT application.
Definition: THttpServer.h:31
Bool_t RegisterCommand(const char *cmdname, const char *method, const char *icon=nullptr)
Register command which can be executed from web interface.
Bool_t CreateItem(const char *fullname, const char *title)
Create item in sniffer.
Bool_t Hide(const char *fullname, Bool_t hide=kTRUE)
Hides folder or element from web gui.
Bool_t Register(const char *subfolder, TObject *obj)
Register object in subfolder.
Bool_t SetItemField(const char *fullname, const char *name, const char *value)
Set item field in sniffer.
Random number generator class based on M.
Definition: TRandom3.h:27
virtual void Rannor(Float_t &a, Float_t &b)
Return 2 numbers distributed following a gaussian with mean=0 and sigma=1.
Definition: TRandom.cxx:500
virtual void Sleep(UInt_t milliSec)
Sleep milliSec milli seconds.
Definition: TSystem.cxx:440
virtual Bool_t ProcessEvents()
Process pending events (GUI, timers, sockets).
Definition: TSystem.cxx:419
const char * cnt
Definition: TXMLSetup.cxx:75
Sergey Linev

Definition in file httpcontrol.C.