From ac90f28589cb3dd7fca245deec3aece0949c554e Mon Sep 17 00:00:00 2001
From: Thomas Anderson <127358482+zc-devs@users.noreply.github.com>
Date: Wed, 18 Oct 2023 14:29:28 +0300
Subject: [PATCH 1/2] Unregister stateless agents from server on termination

---
 agent/rpc/client_grpc.go                  |  5 ++
 cmd/agent/agent.go                        | 20 ++++++-
 cmd/agent/config.go                       |  7 ++-
 cmd/agent/config_test.go                  |  4 +-
 pipeline/backend/kubernetes/kubernetes.go |  6 ++-
 pipeline/rpc/peer.go                      |  3 ++
 pipeline/rpc/proto/version.go             |  2 +-
 pipeline/rpc/proto/woodpecker.pb.go       | 65 ++++++++++++-----------
 pipeline/rpc/proto/woodpecker.proto       | 21 ++++----
 pipeline/rpc/proto/woodpecker_grpc.pb.go  | 59 ++++++++++++++++----
 server/grpc/rpc.go                        | 12 +++++
 server/grpc/server.go                     |  5 ++
 shared/utils/context.go                   |  2 +-
 13 files changed, 151 insertions(+), 60 deletions(-)

diff --git a/agent/rpc/client_grpc.go b/agent/rpc/client_grpc.go
index 070659b88f9..171b5e150d9 100644
--- a/agent/rpc/client_grpc.go
+++ b/agent/rpc/client_grpc.go
@@ -366,6 +366,11 @@ func (c *client) RegisterAgent(ctx context.Context, platform, backend, version s
 	return res.GetAgentId(), err
 }
 
+func (c *client) UnregisterAgent(ctx context.Context) error {
+	_, err := c.client.UnregisterAgent(ctx, &proto.Empty{})
+	return err
+}
+
 func (c *client) ReportHealth(ctx context.Context) (err error) {
 	retry := c.newBackOff()
 	req := new(proto.ReportHealthRequest)
diff --git a/cmd/agent/agent.go b/cmd/agent/agent.go
index 9fde7d28f51..55103785132 100644
--- a/cmd/agent/agent.go
+++ b/cmd/agent/agent.go
@@ -121,9 +121,20 @@ func run(c *cli.Context) error {
 		context.Background(),
 		metadata.Pairs("hostname", hostname),
 	)
+
+	agentConfigPersisted := abool.New()
 	ctx = utils.WithContextSigtermCallback(ctx, func() {
-		println("ctrl+c received, terminating process")
+		log.Info().Msg("Termination signal is received, shutting down")
 		sigterm.Set()
+
+		// Remove stateless agents from server
+		if agentConfigPersisted.IsNotSet() {
+			log.Debug().Msg("Unregistering agent from server")
+			err := client.UnregisterAgent(ctx)
+			if err != nil {
+				log.Err(err).Msg("Failed to unregister agent from server")
+			}
+		}
 	})
 
 	// check if grpc server version is compatible with agent
@@ -160,7 +171,10 @@ func run(c *cli.Context) error {
 		return err
 	}
 
-	writeAgentConfig(agentConfig, agentConfigPath)
+	err = writeAgentConfig(agentConfig, agentConfigPath)
+	if err == nil {
+		agentConfigPersisted.Set()
+	}
 
 	labels := map[string]string{
 		"hostname": hostname,
@@ -182,6 +196,7 @@ func run(c *cli.Context) error {
 	go func() {
 		for {
 			if sigterm.IsSet() {
+				log.Debug().Msg("Terminating health reporting")
 				return
 			}
 
@@ -212,6 +227,7 @@ func run(c *cli.Context) error {
 
 			for {
 				if sigterm.IsSet() {
+					log.Debug().Msgf("terminating runner %d", i)
 					return
 				}
 
diff --git a/cmd/agent/config.go b/cmd/agent/config.go
index 1b6ef3b5eee..ea1791ba627 100644
--- a/cmd/agent/config.go
+++ b/cmd/agent/config.go
@@ -54,11 +54,11 @@ func readAgentConfig(agentConfigPath string) AgentConfig {
 	return conf
 }
 
-func writeAgentConfig(conf AgentConfig, agentConfigPath string) {
+func writeAgentConfig(conf AgentConfig, agentConfigPath string) error {
 	rawAgentConf, err := json.Marshal(conf)
 	if err != nil {
 		log.Error().Err(err).Msg("could not marshal agent config")
-		return
+		return err
 	}
 
 	// get old config
@@ -68,6 +68,9 @@ func writeAgentConfig(conf AgentConfig, agentConfigPath string) {
 	if !bytes.Equal(rawAgentConf, oldRawAgentConf) {
 		if err := os.WriteFile(agentConfigPath, rawAgentConf, 0o644); err != nil {
 			log.Error().Err(err).Msgf("could not persist agent config at '%s'", agentConfigPath)
+			return err
 		}
 	}
+
+	return nil
 }
diff --git a/cmd/agent/config_test.go b/cmd/agent/config_test.go
index 6ae724e1a9c..5ec38c2c13e 100644
--- a/cmd/agent/config_test.go
+++ b/cmd/agent/config_test.go
@@ -44,7 +44,7 @@ func TestReadAgentIDFileExists(t *testing.T) {
 
 	// update existing config and check
 	actual.AgentID = 33
-	writeAgentConfig(actual, tmpF.Name())
+	_ = writeAgentConfig(actual, tmpF.Name())
 	actual = readAgentConfig(tmpF.Name())
 	assert.EqualValues(t, 33, actual.AgentID)
 
@@ -55,7 +55,7 @@ func TestReadAgentIDFileExists(t *testing.T) {
 	defer os.Remove(tmpF2.Name())
 
 	// write new config
-	writeAgentConfig(actual, tmpF2.Name())
+	_ = writeAgentConfig(actual, tmpF2.Name())
 	actual = readAgentConfig(tmpF2.Name())
 	assert.EqualValues(t, 33, actual.AgentID)
 }
diff --git a/pipeline/backend/kubernetes/kubernetes.go b/pipeline/backend/kubernetes/kubernetes.go
index 458a3f08c05..ddac85c66fc 100644
--- a/pipeline/backend/kubernetes/kubernetes.go
+++ b/pipeline/backend/kubernetes/kubernetes.go
@@ -40,6 +40,10 @@ import (
 	_ "k8s.io/client-go/plugin/pkg/client/auth/gcp"
 )
 
+const (
+	EngineName = "kubernetes"
+)
+
 var noContext = context.Background()
 
 type kube struct {
@@ -96,7 +100,7 @@ func New(ctx context.Context) types.Engine {
 }
 
 func (e *kube) Name() string {
-	return "kubernetes"
+	return EngineName
 }
 
 func (e *kube) IsAvailable(context.Context) bool {
diff --git a/pipeline/rpc/peer.go b/pipeline/rpc/peer.go
index c13a557d6fd..08a19217f09 100644
--- a/pipeline/rpc/peer.go
+++ b/pipeline/rpc/peer.go
@@ -79,6 +79,9 @@ type Peer interface {
 	// RegisterAgent register our agent to the server
 	RegisterAgent(ctx context.Context, platform, backend, version string, capacity int) (int64, error)
 
+	// UnregisterAgent unregister our agent from the server
+	UnregisterAgent(ctx context.Context) error
+
 	// ReportHealth reports health status of the agent to the server
 	ReportHealth(c context.Context) error
 }
diff --git a/pipeline/rpc/proto/version.go b/pipeline/rpc/proto/version.go
index 3e3449804ab..1a109d5a8a3 100644
--- a/pipeline/rpc/proto/version.go
+++ b/pipeline/rpc/proto/version.go
@@ -16,4 +16,4 @@ package proto
 
 // Version is the version of the woodpecker.proto file,
 // !IMPORTANT! increased by 1 each time it get changed !IMPORTANT!
-const Version int32 = 4
+const Version int32 = 5
diff --git a/pipeline/rpc/proto/woodpecker.pb.go b/pipeline/rpc/proto/woodpecker.pb.go
index 0fead4b8e0b..891e2af9c24 100644
--- a/pipeline/rpc/proto/woodpecker.pb.go
+++ b/pipeline/rpc/proto/woodpecker.pb.go
@@ -16,7 +16,7 @@
 // Code generated by protoc-gen-go. DO NOT EDIT.
 // versions:
 // 	protoc-gen-go v1.31.0
-// 	protoc        v4.23.4
+// 	protoc        v4.24.4
 // source: woodpecker.proto
 
 package proto
@@ -1181,7 +1181,7 @@ var file_woodpecker_proto_rawDesc = []byte{
 	0x02, 0x20, 0x01, 0x28, 0x03, 0x52, 0x07, 0x61, 0x67, 0x65, 0x6e, 0x74, 0x49, 0x64, 0x12, 0x21,
 	0x0a, 0x0c, 0x61, 0x63, 0x63, 0x65, 0x73, 0x73, 0x5f, 0x74, 0x6f, 0x6b, 0x65, 0x6e, 0x18, 0x03,
 	0x20, 0x01, 0x28, 0x09, 0x52, 0x0b, 0x61, 0x63, 0x63, 0x65, 0x73, 0x73, 0x54, 0x6f, 0x6b, 0x65,
-	0x6e, 0x32, 0x8a, 0x04, 0x0a, 0x0a, 0x57, 0x6f, 0x6f, 0x64, 0x70, 0x65, 0x63, 0x6b, 0x65, 0x72,
+	0x6e, 0x32, 0xbb, 0x04, 0x0a, 0x0a, 0x57, 0x6f, 0x6f, 0x64, 0x70, 0x65, 0x63, 0x6b, 0x65, 0x72,
 	0x12, 0x31, 0x0a, 0x07, 0x56, 0x65, 0x72, 0x73, 0x69, 0x6f, 0x6e, 0x12, 0x0c, 0x2e, 0x70, 0x72,
 	0x6f, 0x74, 0x6f, 0x2e, 0x45, 0x6d, 0x70, 0x74, 0x79, 0x1a, 0x16, 0x2e, 0x70, 0x72, 0x6f, 0x74,
 	0x6f, 0x2e, 0x56, 0x65, 0x72, 0x73, 0x69, 0x6f, 0x6e, 0x52, 0x65, 0x73, 0x70, 0x6f, 0x6e, 0x73,
@@ -1210,19 +1210,22 @@ var file_woodpecker_proto_rawDesc = []byte{
 	0x67, 0x69, 0x73, 0x74, 0x65, 0x72, 0x41, 0x67, 0x65, 0x6e, 0x74, 0x52, 0x65, 0x71, 0x75, 0x65,
 	0x73, 0x74, 0x1a, 0x1c, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x2e, 0x52, 0x65, 0x67, 0x69, 0x73,
 	0x74, 0x65, 0x72, 0x41, 0x67, 0x65, 0x6e, 0x74, 0x52, 0x65, 0x73, 0x70, 0x6f, 0x6e, 0x73, 0x65,
-	0x22, 0x00, 0x12, 0x3a, 0x0a, 0x0c, 0x52, 0x65, 0x70, 0x6f, 0x72, 0x74, 0x48, 0x65, 0x61, 0x6c,
-	0x74, 0x68, 0x12, 0x1a, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x2e, 0x52, 0x65, 0x70, 0x6f, 0x72,
-	0x74, 0x48, 0x65, 0x61, 0x6c, 0x74, 0x68, 0x52, 0x65, 0x71, 0x75, 0x65, 0x73, 0x74, 0x1a, 0x0c,
-	0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x2e, 0x45, 0x6d, 0x70, 0x74, 0x79, 0x22, 0x00, 0x32, 0x43,
-	0x0a, 0x0e, 0x57, 0x6f, 0x6f, 0x64, 0x70, 0x65, 0x63, 0x6b, 0x65, 0x72, 0x41, 0x75, 0x74, 0x68,
-	0x12, 0x31, 0x0a, 0x04, 0x41, 0x75, 0x74, 0x68, 0x12, 0x12, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f,
-	0x2e, 0x41, 0x75, 0x74, 0x68, 0x52, 0x65, 0x71, 0x75, 0x65, 0x73, 0x74, 0x1a, 0x13, 0x2e, 0x70,
-	0x72, 0x6f, 0x74, 0x6f, 0x2e, 0x41, 0x75, 0x74, 0x68, 0x52, 0x65, 0x73, 0x70, 0x6f, 0x6e, 0x73,
-	0x65, 0x22, 0x00, 0x42, 0x38, 0x5a, 0x36, 0x67, 0x69, 0x74, 0x68, 0x75, 0x62, 0x2e, 0x63, 0x6f,
-	0x6d, 0x2f, 0x77, 0x6f, 0x6f, 0x64, 0x70, 0x65, 0x63, 0x6b, 0x65, 0x72, 0x2d, 0x63, 0x69, 0x2f,
-	0x77, 0x6f, 0x6f, 0x64, 0x70, 0x65, 0x63, 0x6b, 0x65, 0x72, 0x2f, 0x70, 0x69, 0x70, 0x65, 0x6c,
-	0x69, 0x6e, 0x65, 0x2f, 0x72, 0x70, 0x63, 0x2f, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x06, 0x70,
-	0x72, 0x6f, 0x74, 0x6f, 0x33,
+	0x22, 0x00, 0x12, 0x2f, 0x0a, 0x0f, 0x55, 0x6e, 0x72, 0x65, 0x67, 0x69, 0x73, 0x74, 0x65, 0x72,
+	0x41, 0x67, 0x65, 0x6e, 0x74, 0x12, 0x0c, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x2e, 0x45, 0x6d,
+	0x70, 0x74, 0x79, 0x1a, 0x0c, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x2e, 0x45, 0x6d, 0x70, 0x74,
+	0x79, 0x22, 0x00, 0x12, 0x3a, 0x0a, 0x0c, 0x52, 0x65, 0x70, 0x6f, 0x72, 0x74, 0x48, 0x65, 0x61,
+	0x6c, 0x74, 0x68, 0x12, 0x1a, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x2e, 0x52, 0x65, 0x70, 0x6f,
+	0x72, 0x74, 0x48, 0x65, 0x61, 0x6c, 0x74, 0x68, 0x52, 0x65, 0x71, 0x75, 0x65, 0x73, 0x74, 0x1a,
+	0x0c, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x2e, 0x45, 0x6d, 0x70, 0x74, 0x79, 0x22, 0x00, 0x32,
+	0x43, 0x0a, 0x0e, 0x57, 0x6f, 0x6f, 0x64, 0x70, 0x65, 0x63, 0x6b, 0x65, 0x72, 0x41, 0x75, 0x74,
+	0x68, 0x12, 0x31, 0x0a, 0x04, 0x41, 0x75, 0x74, 0x68, 0x12, 0x12, 0x2e, 0x70, 0x72, 0x6f, 0x74,
+	0x6f, 0x2e, 0x41, 0x75, 0x74, 0x68, 0x52, 0x65, 0x71, 0x75, 0x65, 0x73, 0x74, 0x1a, 0x13, 0x2e,
+	0x70, 0x72, 0x6f, 0x74, 0x6f, 0x2e, 0x41, 0x75, 0x74, 0x68, 0x52, 0x65, 0x73, 0x70, 0x6f, 0x6e,
+	0x73, 0x65, 0x22, 0x00, 0x42, 0x38, 0x5a, 0x36, 0x67, 0x69, 0x74, 0x68, 0x75, 0x62, 0x2e, 0x63,
+	0x6f, 0x6d, 0x2f, 0x77, 0x6f, 0x6f, 0x64, 0x70, 0x65, 0x63, 0x6b, 0x65, 0x72, 0x2d, 0x63, 0x69,
+	0x2f, 0x77, 0x6f, 0x6f, 0x64, 0x70, 0x65, 0x63, 0x6b, 0x65, 0x72, 0x2f, 0x70, 0x69, 0x70, 0x65,
+	0x6c, 0x69, 0x6e, 0x65, 0x2f, 0x72, 0x70, 0x63, 0x2f, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x06,
+	0x70, 0x72, 0x6f, 0x74, 0x6f, 0x33,
 }
 
 var (
@@ -1277,21 +1280,23 @@ var file_woodpecker_proto_depIdxs = []int32{
 	9,  // 13: proto.Woodpecker.Update:input_type -> proto.UpdateRequest
 	10, // 14: proto.Woodpecker.Log:input_type -> proto.LogRequest
 	13, // 15: proto.Woodpecker.RegisterAgent:input_type -> proto.RegisterAgentRequest
-	12, // 16: proto.Woodpecker.ReportHealth:input_type -> proto.ReportHealthRequest
-	17, // 17: proto.WoodpeckerAuth.Auth:input_type -> proto.AuthRequest
-	14, // 18: proto.Woodpecker.Version:output_type -> proto.VersionResponse
-	15, // 19: proto.Woodpecker.Next:output_type -> proto.NextResponse
-	11, // 20: proto.Woodpecker.Init:output_type -> proto.Empty
-	11, // 21: proto.Woodpecker.Wait:output_type -> proto.Empty
-	11, // 22: proto.Woodpecker.Done:output_type -> proto.Empty
-	11, // 23: proto.Woodpecker.Extend:output_type -> proto.Empty
-	11, // 24: proto.Woodpecker.Update:output_type -> proto.Empty
-	11, // 25: proto.Woodpecker.Log:output_type -> proto.Empty
-	16, // 26: proto.Woodpecker.RegisterAgent:output_type -> proto.RegisterAgentResponse
-	11, // 27: proto.Woodpecker.ReportHealth:output_type -> proto.Empty
-	18, // 28: proto.WoodpeckerAuth.Auth:output_type -> proto.AuthResponse
-	18, // [18:29] is the sub-list for method output_type
-	7,  // [7:18] is the sub-list for method input_type
+	11, // 16: proto.Woodpecker.UnregisterAgent:input_type -> proto.Empty
+	12, // 17: proto.Woodpecker.ReportHealth:input_type -> proto.ReportHealthRequest
+	17, // 18: proto.WoodpeckerAuth.Auth:input_type -> proto.AuthRequest
+	14, // 19: proto.Woodpecker.Version:output_type -> proto.VersionResponse
+	15, // 20: proto.Woodpecker.Next:output_type -> proto.NextResponse
+	11, // 21: proto.Woodpecker.Init:output_type -> proto.Empty
+	11, // 22: proto.Woodpecker.Wait:output_type -> proto.Empty
+	11, // 23: proto.Woodpecker.Done:output_type -> proto.Empty
+	11, // 24: proto.Woodpecker.Extend:output_type -> proto.Empty
+	11, // 25: proto.Woodpecker.Update:output_type -> proto.Empty
+	11, // 26: proto.Woodpecker.Log:output_type -> proto.Empty
+	16, // 27: proto.Woodpecker.RegisterAgent:output_type -> proto.RegisterAgentResponse
+	11, // 28: proto.Woodpecker.UnregisterAgent:output_type -> proto.Empty
+	11, // 29: proto.Woodpecker.ReportHealth:output_type -> proto.Empty
+	18, // 30: proto.WoodpeckerAuth.Auth:output_type -> proto.AuthResponse
+	19, // [19:31] is the sub-list for method output_type
+	7,  // [7:19] is the sub-list for method input_type
 	7,  // [7:7] is the sub-list for extension type_name
 	7,  // [7:7] is the sub-list for extension extendee
 	0,  // [0:7] is the sub-list for field type_name
diff --git a/pipeline/rpc/proto/woodpecker.proto b/pipeline/rpc/proto/woodpecker.proto
index d780f71d2b3..876a4060f42 100644
--- a/pipeline/rpc/proto/woodpecker.proto
+++ b/pipeline/rpc/proto/woodpecker.proto
@@ -24,16 +24,17 @@ package proto;
 
 // Woodpecker Server Service
 service Woodpecker {
-  rpc Version       (Empty)                returns (VersionResponse) {}
-  rpc Next          (NextRequest)          returns (NextResponse) {}
-  rpc Init          (InitRequest)          returns (Empty) {}
-  rpc Wait          (WaitRequest)          returns (Empty) {}
-  rpc Done          (DoneRequest)          returns (Empty) {}
-  rpc Extend        (ExtendRequest)        returns (Empty) {}
-  rpc Update        (UpdateRequest)        returns (Empty) {}
-  rpc Log           (LogRequest)           returns (Empty) {}
-  rpc RegisterAgent (RegisterAgentRequest) returns (RegisterAgentResponse) {}
-  rpc ReportHealth  (ReportHealthRequest)  returns (Empty) {}
+  rpc Version         (Empty)                returns (VersionResponse) {}
+  rpc Next            (NextRequest)          returns (NextResponse) {}
+  rpc Init            (InitRequest)          returns (Empty) {}
+  rpc Wait            (WaitRequest)          returns (Empty) {}
+  rpc Done            (DoneRequest)          returns (Empty) {}
+  rpc Extend          (ExtendRequest)        returns (Empty) {}
+  rpc Update          (UpdateRequest)        returns (Empty) {}
+  rpc Log             (LogRequest)           returns (Empty) {}
+  rpc RegisterAgent   (RegisterAgentRequest) returns (RegisterAgentResponse) {}
+  rpc UnregisterAgent (Empty)                returns (Empty) {}
+  rpc ReportHealth    (ReportHealthRequest)  returns (Empty) {}
 }
 
 //
diff --git a/pipeline/rpc/proto/woodpecker_grpc.pb.go b/pipeline/rpc/proto/woodpecker_grpc.pb.go
index b6f0f6ae148..787f8f6e708 100644
--- a/pipeline/rpc/proto/woodpecker_grpc.pb.go
+++ b/pipeline/rpc/proto/woodpecker_grpc.pb.go
@@ -16,7 +16,7 @@
 // Code generated by protoc-gen-go-grpc. DO NOT EDIT.
 // versions:
 // - protoc-gen-go-grpc v1.3.0
-// - protoc             v4.23.4
+// - protoc             v4.24.4
 // source: woodpecker.proto
 
 package proto
@@ -34,16 +34,17 @@ import (
 const _ = grpc.SupportPackageIsVersion7
 
 const (
-	Woodpecker_Version_FullMethodName       = "/proto.Woodpecker/Version"
-	Woodpecker_Next_FullMethodName          = "/proto.Woodpecker/Next"
-	Woodpecker_Init_FullMethodName          = "/proto.Woodpecker/Init"
-	Woodpecker_Wait_FullMethodName          = "/proto.Woodpecker/Wait"
-	Woodpecker_Done_FullMethodName          = "/proto.Woodpecker/Done"
-	Woodpecker_Extend_FullMethodName        = "/proto.Woodpecker/Extend"
-	Woodpecker_Update_FullMethodName        = "/proto.Woodpecker/Update"
-	Woodpecker_Log_FullMethodName           = "/proto.Woodpecker/Log"
-	Woodpecker_RegisterAgent_FullMethodName = "/proto.Woodpecker/RegisterAgent"
-	Woodpecker_ReportHealth_FullMethodName  = "/proto.Woodpecker/ReportHealth"
+	Woodpecker_Version_FullMethodName         = "/proto.Woodpecker/Version"
+	Woodpecker_Next_FullMethodName            = "/proto.Woodpecker/Next"
+	Woodpecker_Init_FullMethodName            = "/proto.Woodpecker/Init"
+	Woodpecker_Wait_FullMethodName            = "/proto.Woodpecker/Wait"
+	Woodpecker_Done_FullMethodName            = "/proto.Woodpecker/Done"
+	Woodpecker_Extend_FullMethodName          = "/proto.Woodpecker/Extend"
+	Woodpecker_Update_FullMethodName          = "/proto.Woodpecker/Update"
+	Woodpecker_Log_FullMethodName             = "/proto.Woodpecker/Log"
+	Woodpecker_RegisterAgent_FullMethodName   = "/proto.Woodpecker/RegisterAgent"
+	Woodpecker_UnregisterAgent_FullMethodName = "/proto.Woodpecker/UnregisterAgent"
+	Woodpecker_ReportHealth_FullMethodName    = "/proto.Woodpecker/ReportHealth"
 )
 
 // WoodpeckerClient is the client API for Woodpecker service.
@@ -59,6 +60,7 @@ type WoodpeckerClient interface {
 	Update(ctx context.Context, in *UpdateRequest, opts ...grpc.CallOption) (*Empty, error)
 	Log(ctx context.Context, in *LogRequest, opts ...grpc.CallOption) (*Empty, error)
 	RegisterAgent(ctx context.Context, in *RegisterAgentRequest, opts ...grpc.CallOption) (*RegisterAgentResponse, error)
+	UnregisterAgent(ctx context.Context, in *Empty, opts ...grpc.CallOption) (*Empty, error)
 	ReportHealth(ctx context.Context, in *ReportHealthRequest, opts ...grpc.CallOption) (*Empty, error)
 }
 
@@ -151,6 +153,15 @@ func (c *woodpeckerClient) RegisterAgent(ctx context.Context, in *RegisterAgentR
 	return out, nil
 }
 
+func (c *woodpeckerClient) UnregisterAgent(ctx context.Context, in *Empty, opts ...grpc.CallOption) (*Empty, error) {
+	out := new(Empty)
+	err := c.cc.Invoke(ctx, Woodpecker_UnregisterAgent_FullMethodName, in, out, opts...)
+	if err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
 func (c *woodpeckerClient) ReportHealth(ctx context.Context, in *ReportHealthRequest, opts ...grpc.CallOption) (*Empty, error) {
 	out := new(Empty)
 	err := c.cc.Invoke(ctx, Woodpecker_ReportHealth_FullMethodName, in, out, opts...)
@@ -173,6 +184,7 @@ type WoodpeckerServer interface {
 	Update(context.Context, *UpdateRequest) (*Empty, error)
 	Log(context.Context, *LogRequest) (*Empty, error)
 	RegisterAgent(context.Context, *RegisterAgentRequest) (*RegisterAgentResponse, error)
+	UnregisterAgent(context.Context, *Empty) (*Empty, error)
 	ReportHealth(context.Context, *ReportHealthRequest) (*Empty, error)
 	mustEmbedUnimplementedWoodpeckerServer()
 }
@@ -208,6 +220,9 @@ func (UnimplementedWoodpeckerServer) Log(context.Context, *LogRequest) (*Empty,
 func (UnimplementedWoodpeckerServer) RegisterAgent(context.Context, *RegisterAgentRequest) (*RegisterAgentResponse, error) {
 	return nil, status.Errorf(codes.Unimplemented, "method RegisterAgent not implemented")
 }
+func (UnimplementedWoodpeckerServer) UnregisterAgent(context.Context, *Empty) (*Empty, error) {
+	return nil, status.Errorf(codes.Unimplemented, "method UnregisterAgent not implemented")
+}
 func (UnimplementedWoodpeckerServer) ReportHealth(context.Context, *ReportHealthRequest) (*Empty, error) {
 	return nil, status.Errorf(codes.Unimplemented, "method ReportHealth not implemented")
 }
@@ -386,6 +401,24 @@ func _Woodpecker_RegisterAgent_Handler(srv interface{}, ctx context.Context, dec
 	return interceptor(ctx, in, info, handler)
 }
 
+func _Woodpecker_UnregisterAgent_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
+	in := new(Empty)
+	if err := dec(in); err != nil {
+		return nil, err
+	}
+	if interceptor == nil {
+		return srv.(WoodpeckerServer).UnregisterAgent(ctx, in)
+	}
+	info := &grpc.UnaryServerInfo{
+		Server:     srv,
+		FullMethod: Woodpecker_UnregisterAgent_FullMethodName,
+	}
+	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
+		return srv.(WoodpeckerServer).UnregisterAgent(ctx, req.(*Empty))
+	}
+	return interceptor(ctx, in, info, handler)
+}
+
 func _Woodpecker_ReportHealth_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
 	in := new(ReportHealthRequest)
 	if err := dec(in); err != nil {
@@ -447,6 +480,10 @@ var Woodpecker_ServiceDesc = grpc.ServiceDesc{
 			MethodName: "RegisterAgent",
 			Handler:    _Woodpecker_RegisterAgent_Handler,
 		},
+		{
+			MethodName: "UnregisterAgent",
+			Handler:    _Woodpecker_UnregisterAgent_Handler,
+		},
 		{
 			MethodName: "ReportHealth",
 			Handler:    _Woodpecker_ReportHealth_Handler,
diff --git a/server/grpc/rpc.go b/server/grpc/rpc.go
index 7cbdd9a82a7..3a4eb8f88f9 100644
--- a/server/grpc/rpc.go
+++ b/server/grpc/rpc.go
@@ -352,6 +352,18 @@ func (s *RPC) RegisterAgent(ctx context.Context, platform, backend, version stri
 	return agent.ID, nil
 }
 
+func (s *RPC) UnregisterAgent(ctx context.Context) error {
+	agent, err := s.getAgentFromContext(ctx)
+	log.Debug().Msgf("unregistering agent with ID %d", agent.ID)
+	if err != nil {
+		return err
+	}
+
+	err = s.store.AgentDelete(agent)
+
+	return err
+}
+
 func (s *RPC) ReportHealth(ctx context.Context, status string) error {
 	agent, err := s.getAgentFromContext(ctx)
 	if err != nil {
diff --git a/server/grpc/server.go b/server/grpc/server.go
index 44e73277c1d..ff14a907493 100644
--- a/server/grpc/server.go
+++ b/server/grpc/server.go
@@ -163,6 +163,11 @@ func (s *WoodpeckerServer) RegisterAgent(c context.Context, req *proto.RegisterA
 	return res, err
 }
 
+func (s *WoodpeckerServer) UnregisterAgent(ctx context.Context, _ *proto.Empty) (*proto.Empty, error) {
+	err := s.peer.UnregisterAgent(ctx)
+	return new(proto.Empty), err
+}
+
 func (s *WoodpeckerServer) ReportHealth(c context.Context, req *proto.ReportHealthRequest) (*proto.Empty, error) {
 	res := new(proto.Empty)
 	err := s.peer.ReportHealth(c, req.GetStatus())
diff --git a/shared/utils/context.go b/shared/utils/context.go
index 0bc689e6bd6..bb72f8251f7 100644
--- a/shared/utils/context.go
+++ b/shared/utils/context.go
@@ -34,10 +34,10 @@ func WithContextSigtermCallback(ctx context.Context, f func()) context.Context {
 		select {
 		case <-ctx.Done():
 		case <-receivedSignal:
-			cancel(fmt.Errorf("received signal: %v", receivedSignal))
 			if f != nil {
 				f()
 			}
+			cancel(fmt.Errorf("received signal: %v", receivedSignal))
 		}
 	}()
 

From ee86bf78e5b9c7d9f6a3e9cdac4271fca6c7f42d Mon Sep 17 00:00:00 2001
From: 6543 <6543@obermui.de>
Date: Thu, 2 Nov 2023 00:20:50 +0100
Subject: [PATCH 2/2] make stateless agent an option

---
 cmd/agent/agent.go  | 7 ++++---
 cmd/agent/config.go | 4 ++++
 cmd/agent/flags.go  | 2 +-
 3 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/cmd/agent/agent.go b/cmd/agent/agent.go
index f7674903dd9..3eba6a128a1 100644
--- a/cmd/agent/agent.go
+++ b/cmd/agent/agent.go
@@ -176,9 +176,10 @@ func run(c *cli.Context) error {
 		return err
 	}
 
-	err = writeAgentConfig(agentConfig, agentConfigPath)
-	if err == nil {
-		agentConfigPersisted.Set()
+	if agentConfigPath != "" {
+		if err := writeAgentConfig(agentConfig, agentConfigPath); err == nil {
+			agentConfigPersisted.Set()
+		}
 	}
 
 	labels := map[string]string{
diff --git a/cmd/agent/config.go b/cmd/agent/config.go
index ea1791ba627..61e700e1b07 100644
--- a/cmd/agent/config.go
+++ b/cmd/agent/config.go
@@ -35,6 +35,10 @@ func readAgentConfig(agentConfigPath string) AgentConfig {
 		AgentID: defaultAgentIDValue,
 	}
 
+	if agentConfigPath == "" {
+		return conf
+	}
+
 	rawAgentConf, err := os.ReadFile(agentConfigPath)
 	if err != nil {
 		if os.IsNotExist(err) {
diff --git a/cmd/agent/flags.go b/cmd/agent/flags.go
index 481afd4864c..fa43297fed9 100644
--- a/cmd/agent/flags.go
+++ b/cmd/agent/flags.go
@@ -54,7 +54,7 @@ var flags = []cli.Flag{
 	&cli.StringFlag{
 		EnvVars: []string{"WOODPECKER_AGENT_CONFIG_FILE"},
 		Name:    "agent-config",
-		Usage:   "agent config file path",
+		Usage:   "agent config file path, if set empty the agent will be stateless and unregister on termination",
 		Value:   "/etc/woodpecker/agent.conf",
 	},
 	&cli.StringSliceFlag{