support cdn redirection

src/ebusd/bushandler.cpp

@@ -742,7 +742,7 @@ void BusHandler::formatUpdateInfo(ostringstream* output) const {
   }
   unsigned char address = 0;
   for (int index = 0; index < 256; index++, address++) {
-    bool ownAddress = !m_protocol->isOwnAddress(address);
+    bool ownAddress = m_protocol->isOwnAddress(address);
     if (!isValidAddress(address, false) || ((m_seenAddresses[address]&SEEN) == 0 && !ownAddress)) {
       continue;
     }

src/ebusd/main.cpp

@@ -288,8 +288,10 @@ int main(int argc, char* argv[], char* envp[]) {
       logWrite(lf_main, ll_error, "invalid configPath URL");  // force logging on exit
       return EINVAL;
     }
-    if (configHost == CONFIG_HOST) {
-      string suffix = (lang != "en" ? "de" : lang) + "/";
+    bool isCdn = configHost == CONFIG_HOST;
+    string suffix;
+    if (isCdn) {
+      suffix = (lang != "en" ? "de" : lang) + "/";
       configUriPrefix += suffix;
       configPath += suffix;  // only for informational purposes
     } else {
@@ -306,6 +308,27 @@ int main(int argc, char* argv[], char* envp[]) {
       cleanup();
       return EINVAL;
     }
+    if (isCdn) {
+      // check load balancing redirection
+      string redirPath;
+      uint16_t redirPort = 443;
+      string redirProto, redirHost, redirUriPrefix;
+      bool repeat = false;
+      bool json = true;
+      if (configHttpClient->get("/redirect.json", "", &redirPath, nullptr, nullptr, &json) && !json
+      && HttpClient::parseUrl(redirPath, &redirProto, &redirHost, &redirPort, &redirUriPrefix)
+      && redirHost != configHost) {
+        configHttpClient->disconnect();
+        ebusd::HttpClient* redirClient = new HttpClient();
+        if (redirClient->connect(redirHost, redirPort, redirProto == "https", PACKAGE_NAME "/" PACKAGE_VERSION)) {
+          configUriPrefix = redirUriPrefix + suffix;
+          configPath = redirPath + suffix;  // only for informational purposes
+          delete configHttpClient;
+          configHttpClient = redirClient;
+          logNotice(lf_main, "configPath URL redirected to %s", configPath.c_str());
+        }
+      }
+    }
     logInfo(lf_main, "configPath URL is valid");
     configHttpClient->disconnect();
   }

src/ebusd/main_args.cpp

@@ -157,7 +157,7 @@ static const argDef argDefs[] = {
       "arguments for checking a particular scan configuration, e.g. \"FF08070400/0AB5454850303003277201\"."},
   {"scanretries",    O_SCNRET, "COUNT",    0, "Retry scanning devices COUNT times [5]"},
   {"configlang",     O_CFGLNG, "LANG",     0,
-      "Prefer LANG in multilingual configuration files [system default language]"},
+      "Prefer LANG in multilingual configuration files [system default language, DE as fallback]"},
   {"checkconfig",    O_CHKCFG, nullptr,    0, "Check config files, then stop"},
   {"dumpconfig",     O_DMPCFG, "FORMAT", af_optional,
       "Check and dump config files in FORMAT (\"json\" or \"csv\"), then stop"},

src/ebusd/mainloop.cpp

@@ -321,6 +321,10 @@ void MainLoop::run() {
                << ",\"a\":\"other\""
 #endif
                << ",\"u\":" << (now-start);
+          const string configPathCDN = m_scanHelper->getConfigPathCDN();
+          if (!configPathCDN.empty()) {
+            ostr << ",\"cp\":\"" << configPathCDN << "\"";
+          }
           m_protocol->formatInfoJson(&ostr);
           if (m_reconnectCount) {
             ostr << ",\"rc\":" << m_reconnectCount;

src/ebusd/scan.h

@@ -71,6 +71,11 @@ class ScanHelper : public Resolver {
    */
   const string getConfigPath() const { return m_configPath; }
 
+  /**
+   * @return the config path when pointing to CDN, empty otherwise.
+   */
+  const string getConfigPathCDN() const { return m_configUriPrefix.empty() ? "" : m_configPath; }
+
   /**
    * Try to connect to the specified server.
    * @param host the host name to connect to.