Add context service

components/public-api/gitpod/v1/context.proto

@@ -0,0 +1,24 @@
+syntax = "proto3";
+
+package gitpod.v1;
+
+option go_package = "github.com/gitpod-io/gitpod/components/public-api/go/v1";
+
+service ContextService {
+  // ParseContext parses the url and returns the context
+  rpc ParseContext(ParseContextRequest) returns (ParseContextResponse) {}
+}
+
+message ParseContextRequest {
+  string url = 1;
+}
+
+message ParseContextResponse {
+  Context context = 1;
+}
+
+message Context {
+  string title = 1;
+  string normalized_url = 2;
+  string ref = 3;
+}

components/public-api/gitpod/v1/workspace.proto

@@ -88,6 +88,9 @@ message CreateAndStartWorkspaceRequest {
       string create_local_branch = 3;
     }
 
+    // git describes the source refer of workspace
+    // Obtain available git using the ContextService.ParseContext operation if
+    // not sure about it.
     Git git = 1;
   }