# Start by building the application.
FROM golang:1.21 as builder

# Set the Current Working Directory inside the container
WORKDIR /app

# Copy go mod and sum files
COPY go.mod go.sum ./

# Download all dependencies. Dependencies will be cached if the go.mod and go.sum files are not changed
RUN go mod download

# Copy the source from the current directory to the Working Directory inside the container
COPY . .

# Build the Go app
RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -a -installsuffix cgo -o main .

# Start a new stage from scratch
# Alternatively, you could use a very small base image like alpine, but scratch will be smaller
FROM scratch 

# Copy the Pre-built binary file from the previous stage
COPY --from=builder /app/main .

# Expose the port the app runs on
EXPOSE 8080

# Command to run the executable
CMD ["./main"]