Add Static service feature

README.md

@@ -24,14 +24,13 @@ Baker is a dynamic HTTP reverse proxy with a focus on extensibility and flexibil
 - Automatic SSL certificate updates and creation using Let's Encrypt.
 - Configurable rate limiter per domain and path.
 - Prometheus metrics are available at `BAKER_METRICS_ADDRS/metrics`
+- Static Configuration for those services that doesn't expose any config path
 
 # Usage
 
 First, we need to run Baker inside docker. The following `docker-compose.yml`
 
 ```yml
-version: "3.5"
-
 services:
   baker:
     image: ellato/baker:latest
@@ -61,15 +60,13 @@ services:
 
 networks:
   baker:
-    name: baker_net
+    name: baker
     driver: bridge
 ```
 
 Then for each service, the following `docker-compose` can be used. The only requirements are labels and networks. Make sure both baker and service have the same network interface
 
 ```yml
-version: "3.5"
-
 services:
   service1:
     image: service:latest
@@ -79,14 +76,16 @@ services:
       - "baker.network=baker_net"
       - "baker.service.port=8000"
       - "baker.service.ping=/config"
+      - "baker.service.static.domain=xyz.example.com" # only define this if service is not dyanmic
+      - "baker.service.static.path=/*" # only define this if service is not dyanmic
 
     networks:
       - baker
 
 networks:
   baker:
-    external:
-      name: baker_net
+    name: baker
+    external: true
 ```
 
 The service should expose a REST endpoint that returns a configuration. This endpoint acts as a health check and provides real-time configuration.

action.go

@@ -19,6 +19,7 @@ const (
 type Event struct {
 	Type      EventType
 	Container *Container
+	Meta      *MetaData
 	Endpoint  *Endpoint
 	Result    chan struct {
 		Container *Container
@@ -28,7 +29,7 @@ type Event struct {
 
 type ActionRunner struct {
 	pingerCallback func()
-	addCallback    func(*Container)
+	addCallback    func(*Container, *MetaData)
 	updateCallback func(*Container, *Endpoint)
 	removeCallback func(*Container)
 	getCallback    func(string, string) (*Container, *Endpoint)
@@ -43,8 +44,8 @@ func (ar *ActionRunner) Pinger() {
 	ar.push(&Event{Type: pingerEvent})
 }
 
-func (ar *ActionRunner) Add(container *Container) {
-	ar.push(&Event{Type: addEvent, Container: container})
+func (ar *ActionRunner) Add(container *Container, meta *MetaData) {
+	ar.push(&Event{Type: addEvent, Container: container, Meta: meta})
 }
 
 func (ar *ActionRunner) Update(container *Container, endpoint *Endpoint) {
@@ -97,7 +98,7 @@ func WithPingerCallback(callback func()) func(*ActionRunner) {
 	}
 }
 
-func WithAddCallback(callback func(*Container)) func(*ActionRunner) {
+func WithAddCallback(callback func(*Container, *MetaData)) func(*ActionRunner) {
 	return func(ar *ActionRunner) {
 		ar.addCallback = callback
 	}
@@ -149,7 +150,7 @@ func NewActionRunner(bufferSize int, cbs ...ActionCallback) *ActionRunner {
 				case pingerEvent:
 					ar.pingerCallback()
 				case addEvent:
-					ar.addCallback(event.Container)
+					ar.addCallback(event.Container, event.Meta)
 				case updateEvent:
 					ar.updateCallback(event.Container, event.Endpoint)
 				case removeEvent:

data.go

@@ -41,7 +41,12 @@ type Service struct {
 	Endpoint   *Endpoint
 }
 
+type MetaData struct {
+	StaticDomain string
+	StaticPath   string
+}
+
 type Driver interface {
-	Add(*Container)
+	Add(*Container, *MetaData)
 	Remove(*Container)
 }

docker-compose.yml

@@ -1,5 +1,3 @@
-version: "3.5"
-
 services:
   baker:
     #image: ella-to/baker:latest
@@ -30,5 +28,5 @@ services:
 
 networks:
   baker:
-    name: baker_net
+    name: baker
     driver: bridge

driver/docker.go

@@ -18,20 +18,22 @@ type Docker struct {
 	close  chan struct{}
 }
 
-func (d *Docker) loadContainerById(ctx context.Context, id string) (*baker.Container, error) {
+func (d *Docker) loadContainerById(ctx context.Context, id string) (*baker.Container, *baker.MetaData, error) {
 	r, _, err := d.getter(ctx, "/containers/"+id+"/json")
 	if err != nil {
-		return nil, err
+		return nil, nil, err
 	}
 	defer r.Close()
 
 	payload := struct {
 		Config struct {
 			Labels struct {
-				Enable      string `json:"baker.enable"`
-				Network     string `json:"baker.network"`
-				ServicePort string `json:"baker.service.port"`
-				ServicePing string `json:"baker.service.ping"`
+				Enable       string `json:"baker.enable"`
+				Network      string `json:"baker.network"`
+				ServicePort  string `json:"baker.service.port"`
+				ServicePing  string `json:"baker.service.ping"`
+				StaticDomain string `json:"baker.service.static.domain"`
+				StaticPath   string `json:"baker.service.static.path"`
 			} `json:"Labels"`
 		} `json:"Config"`
 		NetworkSettings struct {
@@ -44,40 +46,43 @@ func (d *Docker) loadContainerById(ctx context.Context, id string) (*baker.Conta
 
 	err = json.NewDecoder(r).Decode(&payload)
 	if err != nil {
-		return nil, err
+		return nil, nil, err
 	}
 
 	if payload.Config.Labels.Enable != "true" {
-		return nil, fmt.Errorf("label 'baker.enable' is not set to true")
+		return nil, nil, fmt.Errorf("label 'baker.enable' is not set to true")
 	}
 
 	network, ok := payload.NetworkSettings.Networks[payload.Config.Labels.Network]
 	if !ok {
 		fmt.Println(payload.NetworkSettings.Networks)
-		return nil, fmt.Errorf("network '%s' not exists in labels", payload.Config.Labels.Network)
+		return nil, nil, fmt.Errorf("network '%s' not exists in labels", payload.Config.Labels.Network)
 	}
 
 	port, err := strconv.ParseInt(payload.Config.Labels.ServicePort, 10, 32)
 	if err != nil {
-		return nil, fmt.Errorf("failed to parse port for container '%s' because %s", id, err)
+		return nil, nil, fmt.Errorf("failed to parse port for container '%s' because %s", id, err)
 	}
 
 	var addr netip.AddrPort
 
 	if network.IPAddress != "" {
 		addr, err = netip.ParseAddrPort(fmt.Sprintf("%s:%d", network.IPAddress, port))
 		if err != nil {
-			return nil, fmt.Errorf("failed to parse address for container '%s' because %s", id, err)
+			return nil, nil, fmt.Errorf("failed to parse address for container '%s' because %s", id, err)
 		}
 	}
 
 	slog.Debug("docker driver loaded container", "id", id, "addr", addr, "config", payload.Config.Labels.ServicePing)
 
 	return &baker.Container{
-		Id:         id,
-		Addr:       addr,
-		ConfigPath: payload.Config.Labels.ServicePing,
-	}, nil
+			Id:         id,
+			Addr:       addr,
+			ConfigPath: payload.Config.Labels.ServicePing,
+		}, &baker.MetaData{
+			StaticDomain: payload.Config.Labels.StaticDomain,
+			StaticPath:   payload.Config.Labels.StaticPath,
+		}, nil
 }
 
 func (d *Docker) loadCurrentContainers(ctx context.Context) {
@@ -108,13 +113,13 @@ func (d *Docker) loadCurrentContainers(ctx context.Context) {
 
 		slog.Debug("docker driver received current event", "id", event.ID, "state", event.State)
 
-		container, err := d.loadContainerById(ctx, event.ID)
+		container, meta, err := d.loadContainerById(ctx, event.ID)
 		if err != nil {
 			slog.Error("failed to load container", "id", event.ID, "error", err)
 			continue
 		}
 
-		d.driver.Add(container)
+		d.driver.Add(container, meta)
 	}
 }
 
@@ -152,13 +157,13 @@ func (d *Docker) loadFutureContainers(ctx context.Context) {
 			continue
 		}
 
-		container, err := d.loadContainerById(ctx, event.ID)
+		container, meta, err := d.loadContainerById(ctx, event.ID)
 		if err != nil {
 			slog.Error("failed to load container", "id", event.ID, "error", err)
 			continue
 		}
 
-		d.driver.Add(container)
+		d.driver.Add(container, meta)
 	}
 }
 

examples/hello-world/docker-compose.yml

@@ -1,12 +1,10 @@
-version: "3.5"
-
 services:
   example-service:
     build: .
 
     labels:
       - "baker.enable=true"
-      - "baker.network=baker_net"
+      - "baker.network=baker"
       - "baker.service.port=8000"
       - "baker.service.ping=/config"
 
@@ -15,5 +13,5 @@ services:
 
 networks:
   baker:
-    name: baker_net
-    external: true     
+    name: baker
+    external: true

examples/static/.dockerignore

@@ -0,0 +1,4 @@
+.
+!go.mod
+!go.sum
+!main.go

examples/static/Dockerfile

@@ -0,0 +1,13 @@
+### build stage ###
+FROM golang:1.22-alpine AS builder
+
+WORKDIR /helloworld
+
+COPY . .
+
+RUN go build -o server /helloworld/main.go
+
+### run stage ###
+FROM alpine:latest
+COPY --from=builder /helloworld/server ./server
+CMD ["./server"]

examples/static/README.md

@@ -0,0 +1,21 @@
+# Run the example
+
+Firs, go to the root of the baker project and run the following command to start the baker
+
+```
+docker-compose up
+```
+
+Second, navigate to `examples/static` folder and run the following command
+
+```
+docker-compose up --build --scale example-service=3
+```
+
+There should be some logs prints out in Baker terminal indicating that services are registering
+
+Finally, run the following curl command which demonstrate the dynamic reverse proxy of Baker
+
+```
+curl -H "Host: example.com" http://localhost:80/api/v1
+```

examples/static/docker-compose.yml

@@ -0,0 +1,18 @@
+services:
+  example-static-service:
+    build: .
+
+    labels:
+      - "baker.enable=true"
+      - "baker.network=baker"
+      - "baker.service.port=8000"
+      - "baker.service.static.domain=example.com"
+      - "baker.service.static.path=/*"
+
+    networks:
+      - baker
+
+networks:
+  baker:
+    name: baker
+    external: true     

examples/static/go.mod

@@ -0,0 +1,3 @@
+module helloworld
+
+go 1.22

examples/static/main.go

@@ -0,0 +1,36 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"math/rand"
+	"net/http"
+	"time"
+)
+
+const charset = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
+
+func init() {
+	rand.Seed(time.Now().UnixNano())
+}
+
+func generateRandomString(length int) string {
+	b := make([]byte, length)
+	for i := range b {
+		b[i] = charset[rand.Intn(len(charset))]
+	}
+	return string(b)
+}
+func main() {
+	id := generateRandomString(8)
+
+	http.HandleFunc("/api/v1", func(w http.ResponseWriter, r *http.Request) {
+		fmt.Fprintf(w, "Received from %s: %s\n", id, r.URL.Path)
+	})
+
+	fmt.Printf("Starting server at port 8000\n")
+
+	if err := http.ListenAndServe(":8000", nil); err != nil {
+		log.Fatal(err)
+	}
+}