10-infrastructure.slide

# Infrastructure
Course Go
Tags: golang, go

## Outline

- Linters
- CI/CD
    - GitLab CI/CD
    - GitHub Actions
- Infrastructure
- Cloud
    - GCP

## Linters

## Linters

- Go has a:
    - Built-in formatter
        - `go fmt`
    - Built-in linter
        - `go vet`
- Is there anything better?
    - More static analysis checks
    - Configurable

## golanci-lint

- Go linters runner
    - Runs them in parallel
- Configured using YAML
    - Using `.golangci.yaml`
- Over a hundred of [linters](https://golangci-lint.run/usage/linters/)
- [Custom CLI](https://golangci-lint.run/welcome/install/)

```
$ golangci-lint run
```

[golangci-lint.run](https://golangci-lint.run)

## Configuring golangci-lint

.code assets/lecture-10/linters/golangci.yaml /CONFIG START OMIT/,/CONFIG END OMIT/

[golang-ci-lint.run configuration](https://golangci-lint.run/usage/configuration/)

## Configuring specific golangci-lint linters

.code assets/lecture-10/linters/golangci.yaml /LINTER CONFIG START OMIT/,/LINTER CONFIG END OMIT/

[golang-ci-lint.run configuration](https://golangci-lint.run/usage/configuration/)

## CI/CD

## CI/CD

.image assets/lecture-10/cicd/cicd.svg 500 _

## CI/CD

- _Continuous integration and continuous delivery/deployment_
- Aims to automate software development process

## CI

- Continuous integration
- Involves:
    - Running linters and formatters
    - Checking that code is buildable
    - And that all tests pass
- Generally always triggered
    - On "each" commit
- The CI can be sped up by running just a subset of tests
    - Smoke tests

## CD

- Mostly setup on pushes to the _main_ branch
    - Releases/tags
- Continuous Delivery
    - Shipping update
        - Container/package repositories
- Continuous Deployment
    - Deploying update to production
    - Not always practiced
        - Manual trigger

## Semantic versioning

- **Major.Minor.Patch**
    - `v1.17.5`
- Major
    - Incompatible API changes
- Minor
    - New features
- Patch
    - Bug fixes
- Release candidates
    - Suffixed with `.rc-[NUMBER]`

[Semver](https://semver.org)

## Tags

- Annotated 

```
$ git tag -a v1.17.5 -m "Gophers would approve"
```

- Lightweight

```
$ git tag v1.17.5
```

- Specific commit

```
$ git tag v1.17.5 c3d5e1
```

- Tags have to be pushed explicitly

```
$ git push origin --tags
```

[Git Book: Git Basics - Tagging](https://git-scm.com/book/en/v2/Git-Basics-Tagging)

## GitLab CI/CD

- Built into GitLab
- Configured using the `.gitlab-ci.yaml`
    - Root of project

[GitLab Docs: CI/CD](https://docs.gitlab.com/ee/topics/build_your_application.html)

## GitLab CI/CD (1/2)

.code assets/lecture-10/cicd/gitlab-ci.yaml /START OMIT/,/MIDDLE OMIT/

## GitLab CI/CD (2/2)

.code assets/lecture-10/cicd/gitlab-ci.yaml /MIDDLE OMIT/,/END OMIT/

## GitHub Actions

- GitHub's CI/CD
    - Built into GitHub
- No restrictions for public repositories
- Defined as [worklows](https://docs.github.com/en/actions/learn-github-actions/understanding-github-actions#workflows)
    - Configured using YAML
    - In `.github/workflows/` directory
    - Single workflow can have multiple `jobs`
        - [Job](https://docs.github.com/en/actions/learn-github-actions/understanding-github-actions#jobs) is just a set of steps
- The workflows are then run using [runners](https://docs.github.com/en/actions/learn-github-actions/understanding-github-actions#runners) when a specified [event](https://docs.github.com/en/actions/learn-github-actions/understanding-github-actions#events) occurs

[GitHub Docs: GitHub Actions](https://docs.github.com/en/actions)

## GitHub Actions (1/4)

.code assets/lecture-10/cicd/github-workflow.yaml /START OMIT/,/LINT OMIT/

## GitHub Actions (2/4)

.code assets/lecture-10/cicd/github-workflow.yaml /LINT OMIT/,/TEST OMIT/

## GitHub Actions (3/4)

.code assets/lecture-10/cicd/github-workflow.yaml /TEST OMIT/,/DOCKER SETUP OMIT/

## GitHub Actions (4/4)

.code assets/lecture-10/cicd/github-workflow.yaml /DOCKER SETUP OMIT/,/DOCKER PUSH OMIT/

## GitHub Actions

- Pre-prepared worklow steps
    - No need to write repeating shell command sequences
        - You just use the action
    - Regural GitHub repositories
        - [golangci/golangci-lint-action](https://github.com/golangci/golangci-lint-action)
- Simplify usage of frequent tasks
- [Custom actions](https://docs.github.com/en/actions/creating-actions) can be created

[GitHub Marketplace: Actions](https://github.com/marketplace?type=actions)

## GitHub Packages

- Alternative to [Docker Hub](https://hub.docker.com)
    - Or [GitLab container registry](https://docs.gitlab.com/ee/user/packages/container_registry/)
- Directly linked with repository
    - [course-go/lectures packages](https://github.com/course-go/lectures/pkgs/container/lectures)

[GitHub Docs: GitHub Packages](https://docs.github.com/en/packages)

## Alternatives

- [Jenkins](https://www.jenkins.io)
- [Circle CI](https://circleci.com)
- [TeamCity](https://www.jetbrains.com/teamcity/)

## Deployments

## Deployments

- What do we build apps for?
    - Provides a service to customers
- Apps are useless unless used by customers
    - Developing them is nice
    - But you have to deploy them

## Simple

.image assets/lecture-10/infrastructure/simple.svg 400 _

## Simple

- What if I want to run more services?
- How can I scale service instances?
    - Fault tolerance
    - Distribute load
- HTTPS?
    - Managing certificates

[Sam Rose: Load Balancing](https://samwho.dev/load-balancing/)

## Caddy

- Web server, reverse proxy, load-balancer
    - Alternative to NGINX, Apache etc.
- Native config format is JSON
    - `Caddyfile`
        - More handy
- [Automatic HTTPS](https://caddyserver.com/docs/automatic-https) configuration using [ACME](https://en.wikipedia.org/wiki/Automatic_Certificate_Management_Environment)
    - [ZeroSSL](https://zerossl.com) project
- Supports all HTTP versions
- Extensible using [modules](https://caddyserver.com/docs/modules/)

[Caddy](https://caddyserver.com)

[GitHub: Caddy](https://github.com/caddyserver/caddy)

## Caddyfile

.code assets/lecture-10/infrastructure/Caddyfile

```
$ caddy run
```

## Traefik

- Proxy, edge router (reverse proxy)
    - Alternative to NGINX, HAProxy, Envoy etc.
- Also [supports ACME](https://doc.traefik.io/traefik/https/acme/) providers like [Let's Encrypt](https://letsencrypt.org)
- Includes a CLI, API and GUI dashboard
- Static configuration at startup
- [Dynamic configuration](https://doc.traefik.io/traefik/providers/overview) via providers
    - Docker, Kubernetes, Consul, Nomad, HTTP, ...

```
    labels:
      - traefik.http.routers.my-container.rule=Host(`course-go.dev`)
      - traefik.http.services.my-service.loadbalancer.server.port=12345
```

[Traefik](https://traefik.io/traefik/)

[GitHub: Traefik](https://github.com/traefik/traefik/)

## Traefik Configuration

.code assets/lecture-10/infrastructure/traefik-docker-compose.yaml

.code assets/lecture-10/infrastructure/traefik.yml

## Advanced

.image assets/lecture-10/infrastructure/advanced.svg 420 _

## Advanced

- Progress
    - Single entrypoint
    - Multiple services
    - Multiple instances
- What if our VM dies?
    - Lack of hardware resources
    - Network outage
    - Datacenters can [caught on fire](https://dgtlinfra.com/data-center-fires/)

## Complex

.image assets/lecture-10/infrastructure/complex.svg 550 _

## Cloud

## Cloud

- Allows access to computer system resource and storage
- Major service providers:
    - **Amazon Web Services (AWS)** [~33 %]
    - **Microsoft Azure** [~22 %]
    - **Google Cloud Platform (GCP)** [~11 %]
- All major providers offer plenty of services
- For only hosting VPSs or dedicated servers, consider smaller providers
    - Generally cheaper
    - Honorable mentions:
        - [Hetzner](https://www.hetzner.com), [netcup](https://www.netcup.eu), [Digital Ocean](https://www.digitalocean.com)

[N-iX: AWS vs Azure vs GCP](https://www.n-ix.com/comparing-big-3-aws-azure-gcp/)

## GCP

## GCP

- Google Cloud Platform
    - One of the top three cloud services providers
- Launched in 2008
- Includes plenty of APIs to Google services:
    - Machine learning
        - Gemini
    - Computing
    - Storage
    - Data anylytics

[GCP: Cloud APIs](https://cloud.google.com/apis?hl=en)

## Artifact Registry

- Google's container registry
    - Docker Hub, GitHub Packages, ...
- Allows for easy [CI/CD setup](https://cloud.google.com/docs/application-development#expandable-2)
    - Upload containers to AR
    - Deploy them right away
- Additional features:
    - Vulnerability scanning
- You can setup building of containers in GCP directly
    - [Cloud Build](https://cloud.google.com/build/docs)

[GCP: Artifact Registry](https://cloud.google.com/artifact-registry)

## Compute Engine

- Service for setting up VMs
- Alternatives:
    - Amazon: Elastic Compute Cloud (EC2)
    - Azure: Virtual Machine

[GCP: Compute Engine](https://cloud.google.com/products/compute?hl=en)

## Cloud Run

- Service for running containers
    - Serverless
- Allows you to scale to 0
    - Cost
- Alternatives:
    - Amazon: App Runner
    - Azure: Container Apps

[GCP: Cloud Run](https://cloud.google.com/run?hl=en)

## GKE

- Google Kubernetes Engine
- [Autopilot](https://cloud.google.com/kubernetes-engine/docs/concepts/autopilot-overview) can manage your infrastructure
    - Serverless
- Alternatives:
    - Amazon: Elastic Kubernetes Service (EKS)
    - Azure: Azure Kubernetes Service (AKS)

[GCP: GKE](https://cloud.google.com/kubernetes-engine?hl=en)

## VPC

- Virtual Private Cloud
- Network service
    - Allows you to setup virtual topology
    - Allows network sharing across projects
- Alternatives:
    - Amazon: Virtual Private Cloud
    - Azure: Virtual Network

[GCP: VPC](https://cloud.google.com/vpc?hl=en)

## Cloud SQL

- Service for running SQL database instances
- Currently supports MySQL, PostgresSQL, and SQL Server
- Alternatives:
    - Amazon: Simple Storage Service (S3)
    - Azure: Blob Storage

[GCP: Cloud SQL](https://cloud.google.com/sql?hl=en)

## Cloud Storage

- Object storage
    - Files, videos, photos, ...
- Structured using buckets
    - Directory structure
- Alternatives:
    - Amazon: Simple Storage Service (S3)
    - Azure: Blob Storage
    - Open-source: [Minio](https://github.com/minio/minio)

[GCP: Cloud Storage](https://cloud.google.com/storage?hl=en)