First prototype

Change-Id: Ieceb55636bda133466609471f25508d0ae83c52c
diff --git a/api_proto/common.proto b/api_proto/common.proto
new file mode 100644
index 0000000..fd5867e
--- /dev/null
+++ b/api_proto/common.proto
@@ -0,0 +1,21 @@
+syntax = "proto3";
+
+option go_package = "gomodules.avm99963.com/twpt-server/api_proto";
+
+message Environment {
+  enum Browser {
+    BROWSER_UNKNOWN = 0;
+    BROWSER_CHROMIUM = 1;
+    BROWSER_GECKO = 2;
+  }
+
+  enum VersionChannel {
+    CHANNEL_UNKNOWN = 0;
+    CHANNEL_STABLE = 1;
+    CHANNEL_BETA = 2;
+  }
+
+  Browser browser = 1;
+  string version = 2;
+  VersionChannel version_channel = 3;
+}