From 26d8bc2d93ace3fac908388e53dfd4d982f7faa4 Mon Sep 17 00:00:00 2001
From: njucz <zhcheng@microsoft.com>
Date: Tue, 11 Aug 2020 16:38:31 +0800
Subject: [PATCH] prevent block the main goroutine when waiting user's action

---
 langserver/handlers/did_open.go | 61 ++++++++++++++++++---------------
 1 file changed, 34 insertions(+), 27 deletions(-)

diff --git a/langserver/handlers/did_open.go b/langserver/handlers/did_open.go
index dc528ca12..8e4ce8ea6 100644
--- a/langserver/handlers/did_open.go
+++ b/langserver/handlers/did_open.go
@@ -44,40 +44,47 @@ func (lh *logHandler) TextDocumentDidOpen(ctx context.Context, params lsp.DidOpe
 		lh.logger.Printf("walker has not finished walking yet, data may be inaccurate for %s", f.FullPath())
 	} else if len(candidates) == 0 {
 		// TODO: Only notify once per f.Dir() per session
-		msg := fmt.Sprintf("No root module found for %q."+
-			" Functionality may be limited."+
-			// Unfortunately we can't be any more specific wrt where
-			// because we don't gather "init-able folders" in any way
-			" You may need to run terraform init"+
-			" and reload your editor.", readableDir)
-		resp, _ := jrpc2.PushCall(ctx, "window/showMessageRequest", lsp.ShowMessageRequestParams{
-			Type:    lsp.MTWarning,
-			Message: msg,
-			Actions: []lsp.MessageActionItem{
-				{
-					Title: "run `terraform init`",
+		go func() {
+			msg := fmt.Sprintf("No root module found for %q."+
+				" Functionality may be limited."+
+				// Unfortunately we can't be any more specific wrt where
+				// because we don't gather "init-able folders" in any way
+				" You may need to run terraform init"+
+				" and reload your editor.", readableDir)
+			resp, err := jrpc2.PushCall(ctx, "window/showMessageRequest", lsp.ShowMessageRequestParams{
+				Type:    lsp.MTWarning,
+				Message: msg,
+				Actions: []lsp.MessageActionItem{
+					{
+						Title: "run `terraform init`",
+					},
 				},
-			},
-		})
-		var action lsp.MessageActionItem
-		if err := resp.UnmarshalResult(&action); err != nil {
-			return err
-		}
-		if action.Title == "run `terraform init`" {
-			rmm, err := lsctx.RootModuleManager(ctx)
+			})
 			if err != nil {
-				return err
+				lh.logger.Printf("%+v", err)
+				return
 			}
-			rm, err := rmm.NewPotentialRootModule(f.Dir())
-			if err != nil {
-				return err
+			var action lsp.MessageActionItem
+			if err := resp.UnmarshalResult(&action); err != nil {
+				lh.logger.Printf("unmarshal MessageActionItem: %+v", err)
+				return
 			}
-			go func() {
+			if action.Title == "run `terraform init`" {
+				rmm, err := lsctx.RootModuleManager(ctx)
+				if err != nil {
+					lh.logger.Printf("%+v", err)
+					return
+				}
+				rm, err := rmm.NewPotentialRootModule(f.Dir())
+				if err != nil {
+					lh.logger.Printf("%+v", err)
+					return
+				}
 				if err := rm.ExecuteTerraformInit(ctx); err != nil {
 					lh.logger.Printf("failed to execute `terraform init`: %+v", err)
 				}
-			}()
-		}
+			}
+		}()
 	}
 	if len(candidates) > 1 {
 		candidateDir := humanReadablePath(rootDir, candidates[0].Path())