drastically reduced image size by multistaging and introducing docker ignore (from ~1.6 GB to 20 MB)

.dockerignore

@@ -0,0 +1,8 @@
+*
+# exluding everything and only allowing directly relevant stuff
+!cmd/server/main.go
+!internal
+!tokens
+!go.mod
+!go.sum
+!server

.gitignore

@@ -17,9 +17,10 @@
 # vendor/
 
 # binaries
-bin/*
+bin
 *.tar.gz
 # logs
 *.log
 
 tokens
+logs

Dockerfile.server

@@ -1,5 +1,5 @@
 # syntax=docker/dockerfile:1
-FROM golang:1.18
+FROM golang:1.18-alpine as builder
 
 WORKDIR /app
 
@@ -7,12 +7,17 @@ COPY . .
 
 RUN go mod download
 
-RUN go build -o /server ./cmd/server/main.go
+RUN CGO_ENABLED=0 go build -o /server ./cmd/server/main.go
+
+FROM alpine
+
+COPY --from=builder /server .
+COPY --from=builder /app/tokens/ ./tokens
 
 EXPOSE 2022
 EXPOSE 2023
 
-CMD [ "/server" ]
+ENTRYPOINT [ "./server" ]
 
 
 

internal/pkg/reactor/rlcoordinator.go

@@ -97,7 +97,7 @@ func NewCoordinator(ip string,port int,ch chan error) *Coordinator {
     c.Ip = ip
     c.Port = port
     c.hw = &hw{}
-    c.HB = time.Duration(1 * time.Second)
+    c.HB = time.Duration(5 * time.Second)
     c.PingTimer = make(chan struct{})
     // this is going to be scuffed
     url := fmt.Sprintf("http://%s:8086",ip)