From 52b24757c9cab54f70e3db30100a679f83e12f3e Mon Sep 17 00:00:00 2001
From: Thulinma <jaron@vietors.com>
Date: Tue, 10 Jul 2018 09:44:50 +0200
Subject: [PATCH] Added support for JSONP mode and CORS headers to JSON
 Prometheus output

---
 src/controller/controller_api.cpp        |  2 +-
 src/controller/controller_statistics.cpp | 10 ++++++++++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/src/controller/controller_api.cpp b/src/controller/controller_api.cpp
index fed43598..7427849d 100644
--- a/src/controller/controller_api.cpp
+++ b/src/controller/controller_api.cpp
@@ -317,7 +317,7 @@ int Controller::handleAPIConnection(Socket::Connection & conn){
           H.Clean();
           continue;
         }
-        if (H.url == "/"+Controller::prometheus+".json"){
+        if (H.url.substr(0, Controller::prometheus.size()+6) == "/"+Controller::prometheus+".json"){
           handlePrometheus(H, conn, PROMETHEUS_JSON);
           H.Clean();
           continue;
diff --git a/src/controller/controller_statistics.cpp b/src/controller/controller_statistics.cpp
index 29785d18..4ea7c903 100644
--- a/src/controller/controller_statistics.cpp
+++ b/src/controller/controller_statistics.cpp
@@ -1479,12 +1479,16 @@ void Controller::fillTotals(JSON::Value & req, JSON::Value & rep){
 }
 
 void Controller::handlePrometheus(HTTP::Parser & H, Socket::Connection & conn, int mode){
+  std::string jsonp;
   switch (mode){
     case PROMETHEUS_TEXT:
       H.SetHeader("Content-Type", "text/plain; version=0.0.4");
       break;
     case PROMETHEUS_JSON:
       H.SetHeader("Content-Type", "text/json");
+      H.setCORSHeaders();
+      if (H.GetVar("callback") != ""){jsonp = H.GetVar("callback");}
+      if (H.GetVar("jsonp") != ""){jsonp = H.GetVar("jsonp");}
       break;
   }
   H.SetHeader("Server", "MistServer/" PACKAGE_VERSION);
@@ -1805,7 +1809,13 @@ void Controller::handlePrometheus(HTTP::Parser & H, Socket::Connection & conn, i
       }
     }
 
+    if (jsonp.size()){
+      H.Chunkify(jsonp + "(", conn);
+    }
     H.Chunkify(resp.toString(), conn);
+    if (jsonp.size()){
+      H.Chunkify(");\n", conn);
+    }
   }
 
   H.Chunkify("", conn);