From 73941a3066d35598cedaeaf858ab7fbf857fe3f9 Mon Sep 17 00:00:00 2001
From: Austin Schey <aschey13@gmail.com>
Date: Mon, 26 Apr 2021 04:43:42 -0500
Subject: [PATCH] Immediately retry a disconnected grpc connection before
 attempting to send a request (#61)

* update wails and go versions, remove mewn dependency

* retry connection on request

* update changelog, revert other changes

* formatting

* use once instead of on for single use callback
---
 .github/workflows/package.yml |  1 -
 CHANGELOG.md                  |  1 +
 internal/app/api.go           | 19 +++++++++++++++++--
 3 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/.github/workflows/package.yml b/.github/workflows/package.yml
index e64a73a..6d77b87 100644
--- a/.github/workflows/package.yml
+++ b/.github/workflows/package.yml
@@ -174,4 +174,3 @@ jobs:
         asset_path: Wombat_${{ steps.version.outputs.tag }}_Windows_x86_64.zip/Wombat_${{ steps.version.outputs.tag }}_Windows_x86_64.zip
         asset_name: Wombat_${{ steps.version.outputs.tag }}_Windows_x86_64.zip
         asset_content_type: application/octet-stream
-
diff --git a/CHANGELOG.md b/CHANGELOG.md
index de47b85..7e1cb5f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 - Support export/import request to/from grpcurl command. Thanks to [@devkanro](https://github.com/devkanro) & [@iou90](https://github.com/iou90)
+- Immediately retry a disconnected grpc connection before attempting to send a request. Thanks to [@aschey](https://github.com/aschey) 
 
 ### Fixed
 - Update dependencies to fix an issue with newer versions of webkit2gtk. Thanks to [@aschey](https://github.com/aschey)
diff --git a/internal/app/api.go b/internal/app/api.go
index 0a1039c..f44247a 100644
--- a/internal/app/api.go
+++ b/internal/app/api.go
@@ -709,6 +709,19 @@ func fieldViewsFromDesc(fds protoreflect.FieldDescriptors, isOneof bool, cd *cyc
 	return fields, nil
 }
 
+func (a *api) RetryConnection() {
+	state := a.client.conn.GetState()
+	if state == connectivity.TransientFailure || state == connectivity.Shutdown {
+		// State is currently disconnected. Do a quick retry in case the server restarted recently.
+		a.client.conn.ResetConnectBackoff()
+		stateChanged := make(chan bool)
+		waitForStateChange := func(data ...interface{}) { stateChanged <- true }
+		a.runtime.Events.Once(eventClientStateChanged, waitForStateChange)
+		// Wait for at least one retry to complete before continuing
+		<-stateChanged
+	}
+}
+
 func (a *api) Send(method string, rawJSON []byte, rawHeaders interface{}) (rerr error) {
 	defer func() {
 		if rerr != nil {
@@ -718,6 +731,8 @@ func (a *api) Send(method string, rawJSON []byte, rawHeaders interface{}) (rerr
 		}
 	}()
 
+	a.RetryConnection()
+
 	md, err := a.getMethodDesc(method)
 	if err != nil {
 		return err
@@ -1033,8 +1048,8 @@ func (a *api) ImportCommand(kind string, command string) (rerr error) {
 			return err
 		}
 
-		return a.emitServicesSelect("/" + args.Method, args.Data, args.Metadata)
+		return a.emitServicesSelect("/"+args.Method, args.Data, args.Metadata)
 	}
 
 	return nil
-}
\ No newline at end of file
+}