smaller image

Src/Backend/foodApi/Dockerfile

@@ -1,15 +1,61 @@
-# Take from https://medium.com/@uxioandrade/implementing-session-caching-in-go-with-gin-sessions-redis-and-docker-838608f6cca
-# Last build size was 996MB, which having 809MB as golang:latest
-FROM golang:latest
-
+# https://blog.golang.org/docker
+# Start from a Debian image with the latest version of Go installed
+# and a workspace (GOPATH) configured at /go.
+# FROM s390x/golang:1.14-alpine
+############################
+# STEP 1 build executable binary
+############################
+# golang alpine 1.13.5
+FROM golang@sha256:0991060a1447cf648bab7f6bb60335d1243930e38420bee8fec3db1267b84cfa as builder
 ENV GO111MODULE=on
-
-WORKDIR /app
-
-COPY ./go.mod .
-COPY ./go.sum .
-
-RUN go mod download
-
+# Install git + SSL ca certificates.
+# Git is required for fetching the dependencies.
+# Ca-certificates is required to call HTTPS endpoints.
+# Else you will get error => local error: tls: bad record MAC 
+RUN apk update && apk add --no-cache git ca-certificates tzdata && update-ca-certificates
+# Create appuser
+ENV USER=appuser
+ENV UID=10001
+# Install git + SSL ca certificates.
+# Git is required for fetching the dependencies.
+# Ca-certificates is required to call HTTPS endpoints.
+# RUN apk update && apk add --no-cache git ca-certificates tzdata && update-ca-certificates
+# See https://stackoverflow.com/a/55757473/12429735
+RUN adduser \
+   --disabled-password \
+   --gecos "" \
+   --home "/nonexistent" \
+   --shell "/sbin/nologin" \
+   --no-create-home \
+   --uid "${UID}" \
+   "${USER}"
+WORKDIR $GOPATH/src/mypackage/myapp/
 COPY . .
-CMD ["go","run","main.go"]
+# Fix the error cannot find package "golang.org/x/net/html" in any of:
+# default: #10 0.286  /usr/local/go/src/golang.org/x/net/html (from $GOROOT)
+# default: #10 0.286  /go/src/golang.org/x/net/html (from $GOPATH)
+RUN go mod vendor
+RUN ls
+# Build the binary
+# RUN CGO_ENABLED=0 GOOS=linux go build -ldflags="-w -s" -o /go/bin/hello main.go
+# -mod vendor 
+RUN CGO_ENABLED=0 GOOS=linux go build -ldflags="-w -s" -o /go/bin/hello -mod vendor main.go
+############################
+# STEP 2 build a small image
+############################
+FROM scratch
+# Import from builder.
+COPY --from=builder /usr/share/zoneinfo /usr/share/zoneinfo
+COPY --from=builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/
+COPY --from=builder /etc/passwd /etc/passwd
+COPY --from=builder /etc/group /etc/group
+# Copy our static executable
+COPY --from=builder /go/bin/hello /go/bin/hello
+# Use an unprivileged user.
+USER appuser:appuser
+# Run the hello binary.
+ENTRYPOINT ["/go/bin/hello"]
+# Run the outyet command by default when the container starts.
+# ENTRYPOINT /go/bin/outyet
+# Document that the service listens on port 8080.
+EXPOSE 8080