Added ability to change location of configuration folder using TB_GW_…

…CONFIG_DIR environmental variable

thingsboard_gateway/tb_gateway.py

@@ -12,12 +12,11 @@
 #     See the License for the specific language governing permissions and
 #     limitations under the License.
 import sys
-from os import curdir, listdir, mkdir, path
+from os import curdir, listdir, mkdir, path, environ
 
 from thingsboard_gateway.gateway.tb_gateway_service import TBGatewayService
 from thingsboard_gateway.gateway.hot_reloader import HotReloader
 
-
 def main():
     if "logs" not in listdir(curdir):
         mkdir("logs")
@@ -30,11 +29,19 @@ def main():
     if hot_reload:
         HotReloader(TBGatewayService)
     else:
-        TBGatewayService(path.dirname(path.abspath(__file__)) + '/config/tb_gateway.json'.replace('/', path.sep))
+        config_path = __get_config_path(path.dirname(path.abspath(__file__)) + '/config/'.replace('/', path.sep))
+        TBGatewayService(config_path + 'tb_gateway.json')
 
 
 def daemon():
-    TBGatewayService("/etc/thingsboard-gateway/config/tb_gateway.json".replace('/', path.sep))
+    config_path = __get_config_path("/etc/thingsboard-gateway/config/".replace('/', path.sep))
+    TBGatewayService(config_path + "tb_gateway.json")
+
+def __get_config_path(default_config_path):
+    config_path = environ.get("TB_GW_CONFIG_DIR", default_config_path)
+    if not config_path.endswith(path.sep):
+        config_path += path.sep
+    return config_path
 
 
 if __name__ == '__main__':