Advanced Docker Concepts and Features

1. Multi-stage Builds

Multi-stage builds allow you to create more efficient Dockerfiles by
using multiple FROM statements in your Dockerfile.

# Build stage
FROM golang:1.16 AS builder
WORKDIR /app
COPY . .
RUN go build -o main .
# Final stage
FROM alpine:latest
RUN apk --no-cache add ca-certificates
WORKDIR /root/
COPY --from=builder /app/main .
CMD ["./main"]

This approach reduces the final image size by only including necessary
artifacts from the build stage

2. Docker BuildKit

BuildKit is a next-generation build engine for Docker. Enable it by
setting an environment variable:

export DOCKER_BUILDKIT=1

BuildKit offers faster builds, better cache management, and advanced
features like:
Concurrent dependency resolution
Efficient instruction caching
Automatic garbage collection

3. Custom Bridge Networks

Create isolated network environments for your containers:

docker network create --driver bridge isolated_network
docker run --network=isolated_network --name container1 -d
nginx
docker run --network=isolated_network --name container2 -d
nginx

Containers on this network can communicate using their names as hostnames

4. Docker Contexts

Manage multiple Docker environments with contexts:

# Create a new context
docker context create my-remote --docker
"host=ssh://user@remote-host"
# List contexts
docker context ls
# Switch context
docker context use my-remote

1. Docker Content Trust (DCT)

DCT provides a way to verify the integrity and publisher of images:

# Enable DCT
export DOCKER_CONTENT_TRUST=1
# Push a signed image
docker push myrepo/myimage:latest

6. Docker Secrets

Manage sensitive data with Docker secrets:

# Create a secret
echo "mypassword" | docker secret create my_secret -
# Use the secret in a service
docker service create --name myservice --secret my_secret
myimage

7.Docker Manifest

Create and push multi-architecture images:

docker manifest create myrepo/myimage myrepo/myimage:amd64
myrepo/myimage:arm64
docker manifest push myrepo/myimage