Remote & Dev Containers

# 1) The Remote Development extension pack
# Install from the marketplace: 'Remote Development' (Microsoft)
# Bundle includes:
#   • Remote - SSH
#   • Remote - Tunnels
#   • Dev Containers
#   • WSL (Windows only)
# For Codespaces: 'GitHub Codespaces' extension (auto-installed by GitHub)

# Architecture:
#   Local VS Code (UI, settings, extensions)
#     ⇅ VS Code Server (runs on remote)
#     ⇅ Remote filesystem + tools

# 2) Remote - SSH (most common)
# Prerequisites:
#   • SSH client on local machine
#   • SSH access to a Linux/macOS host (Linux preferred)
#   • Tool path on remote: bash, curl, tar

# Connect:
# 1) Cmd/Ctrl+Shift+P → 'Remote-SSH: Connect to Host'
# 2) Pick host from ~/.ssh/config or 'Add New SSH Host'
# 3) VS Code installs vscode-server on remote (~ 200 MB cached)
# 4) Open folder on remote

# ~/.ssh/config example
Host dev-box
    HostName dev.example.internal
    User mara
    IdentityFile ~/.ssh/dev_ed25519
    ForwardAgent yes

Host jump-prod
    HostName bastion.example.com
    User mara
    IdentityFile ~/.ssh/jump_ed25519

Host prod-app
    HostName 10.0.0.42
    User mara
    ProxyJump jump-prod

# Now: 'Connect to Host' → dev-box → workspace files load.

# 3) Settings — local vs remote
# • Local settings.json: editor UI, themes
# • Remote settings.json: workspace-specific, language tooling, formatters
# • Workspace settings: committed to repo (.vscode/settings.json)

# Extensions are split:
#   • UI extensions stay LOCAL (themes, keymap)
#   • Workspace extensions install on REMOTE (language servers, debuggers)
# Settings sync still works across local sessions.

# 4) Dev Containers
# Code lives in a Docker container. Reproducible env per project.
# .devcontainer/devcontainer.json
{
    "name": "My Project",
    "image": "mcr.microsoft.com/devcontainers/typescript-node:20",
    "customizations": {
        "vscode": {
            "extensions": [
                "dbaeumer.vscode-eslint",
                "esbenp.prettier-vscode"
            ],
            "settings": {
                "editor.formatOnSave": true
            }
        }
    },
    "forwardPorts": [3000, 5432],
    "postCreateCommand": "npm install",
    "remoteUser": "node"
}

# Use: Cmd/Ctrl+Shift+P → 'Dev Containers: Reopen in Container'
# VS Code builds the container + connects to it.

# Features for Postgres, Redis, etc:
{
    "features": {
        "ghcr.io/devcontainers/features/docker-in-docker:2": {},
        "ghcr.io/devcontainers/features/github-cli:1": {}
    }
}

# Docker Compose-backed dev containers
{
    "dockerComposeFile": "docker-compose.yml",
    "service": "app",
    "workspaceFolder": "/workspaces/myapp"
}

# 5) WSL (Windows Subsystem for Linux)
# • Install Ubuntu via 'wsl --install -d Ubuntu-22.04'
# • Cmd/Ctrl+Shift+P → 'WSL: Connect to WSL' or 'WSL: New WSL Window'
# • Code on Linux filesystem, edit from Windows UI
# • Performance: keep code in WSL filesystem (/home/user) NOT /mnt/c (mount slowdown)

# 6) GitHub Codespaces — cloud-hosted dev containers
# • github.com/<repo> → green Code button → Codespaces tab
# • Or VS Code Command Palette: 'Codespaces: Create New Codespace'
# • Container spec from devcontainer.json (or default)
# • Per-codespace billing; idle suspension

# 7) Tunnels — connect to your local machine from anywhere
# Lightweight alternative to setting up SSH:
# Cmd/Ctrl+Shift+P → 'Remote-Tunnels: Turn on Remote Tunnel Access...'
# Sign in with GitHub → get a URL like vscode.dev/tunnel/my-name
# Access from any other device's browser or VS Code.

# 8) Performance tips
# • Big repos with many files — exclude node_modules from search/watch:
{
    "files.exclude":  { "**/node_modules": true, "**/dist": true },
    "search.exclude": { "**/node_modules": true, "**/dist": true },
    "files.watcherExclude": { "**/node_modules/**": true }
}

# • Disable heavy extensions on remote
# • Use SSH ControlMaster for faster reconnects
# • Codespaces: pick a higher-CPU machine type for heavy builds

# 9) Port forwarding
# Remote-SSH and dev containers auto-forward when a server listens on a port.
# Manually forward: 'Forward a Port' in the Ports panel.
# Set forwardPorts in devcontainer.json so they always show.
# Public visibility (Codespaces) — can share preview URLs.

# 10) File system + git operations on remote
# • Terminal runs on the REMOTE
# • Git uses REMOTE credentials (or forwarded SSH agent)
# • File saves go to REMOTE
# • Drag-drop from local explorer copies via remote workspace

# 11) Common workflows
# • Multiple branches / projects per dev container → context isolation
# • Travel laptop + powerful workstation → SSH into workstation
# • Onboarding → 'Reopen in Container' brings a working dev env in minutes
# • CI consistency → run the same dev container in GitHub Actions

# 12) Security
# • Remote-SSH uses your local SSH config; permissions you have apply
# • Dev containers run as the user defined (remoteUser)
# • Tunnels use GitHub auth — fine for trusted personal use
# • For org policy, restrict tunnel use; use SSO + provisioned containers

# 13) Common bugs
# • 'Could not establish connection to xyz' — check ssh xyz works in plain shell
# • Slow remote on first connect — vscode-server downloading; subsequent connects fast
# • Extension not installing on remote — needs different host CPU arch (musl vs glibc)
# • Port not forwarding — explicit forwardPorts entry; check firewall on remote
# • Dev container build cache miss — use Docker buildx + multi-stage; commit Dockerfile carefully
# • Codespaces idle suspend then long startup — set idle longer or use prebuilds
# • Settings sync clashing with remote settings — settings sync is per-machine; use workspace settings for project rules
# • WSL slow on /mnt/c paths — move code to /home/user
# • Tunnels disconnecting → require GitHub re-auth after 7 days
# • Multiple windows on same host → server prefers one workspace; spawn new window with 'New Window from Remote'

// Remote — SSH:  edit code on a remote machine as if it were local.
// Dev Containers: open a project inside a Docker container with all deps preinstalled.
// WSL: same for Linux on Windows.