azd-deployment skill

```skill
---
name: azd-deployment
description: Deploy containerized applications to Azure Container Apps using Azure Developer CLI (azd). Use when setting up azd projects, writing azure.yaml configuration, creating Bicep infrastructure for Container Apps, configuring remote builds with ACR, implementing idempotent deployments, managing environment variables across local/.azure/Bicep, or troubleshooting azd up failures. Triggers on requests for azd configuration, Container Apps deployment, multi-service deployments, and infrastructure-as-code with Bicep.
---

# Azure Developer CLI (azd) Container Apps Deployment

Deploy containerized frontend + backend applications to Azure Container Apps with remote builds, managed identity, and idempotent infrastructure.

## Quick Start

```bash
# Initialize and deploy
azd auth login
azd init                    # Creates azure.yaml and .azure/ folder
azd env new <env-name>      # Create environment (dev, staging, prod)
azd up                      # Provision infra + build + deploy
```

## Core File Structure

```
project/
├── azure.yaml              # azd service definitions + hooks
├── infra/
│   ├── main.bicep          # Root infrastructure module
│   ├── main.parameters.json # Parameter injection from env vars
│   └── modules/
│       ├── container-apps-environment.bicep
│       └── container-app.bicep
├── .azure/
│   ├── config.json         # Default environment pointer
│   └── <env-name>/
│       ├── .env            # Environment-specific values (azd-managed)
│       └── config.json     # Environment metadata
└── src/
    ├── frontend/Dockerfile
    └── backend/Dockerfile
```

## azure.yaml Configuration

### Minimal Configuration

```yaml
name: my-project
services:
  backend:
    project: ./src/backend
    language: python
    host: containerapp
    docker:
      path: ./Dockerfile
      remoteBuild: true
```

### Full Configuration with Hooks

```yaml
name: my-project
metadata:
  template: [email protected]

infra:
  provider: bicep
  path: ./infra

azure:
  location: eastus2

services:
  frontend:
    project: ./src/frontend
    language: ts
    host: containerapp
    docker:
      path: ./Dockerfile
      context: .
      remoteBuild: true

  backend:
    project: ./src/backend
    language: python
    host: containerapp
    docker:
      path: ./Dockerfile
      context: .
      remoteBuild: true

hooks:
  preprovision:
    shell: sh
    run: |
      echo "Before provisioning..."
      
  postprovision:
    shell: sh
    run: |
      echo "After provisioning - set up RBAC, etc."
      
  postdeploy:
    shell: sh
    run: |
      echo "Frontend: ${SERVICE_FRONTEND_URI}"
      echo "Backend: ${SERVICE_BACKEND_URI}"
```

### Key azure.yaml Options

| Option | Description |
|--------|-------------|
| `remoteBuild: true` | Build images in Azure Container Registry (recommended) |
| `context: .` | Docker build context relative to project path |
| `host: containerapp` | Deploy to Azure Container Apps |
| `infra.provider: bicep` | Use Bicep for infrastructure |

## Environment Variables Flow

### Three-Level Configuration

1. **Local `.env`** - For local development only
2. **`.azure/<env>/.env`** - azd-managed, auto-populated from Bicep outputs
3. **`main.parameters.json`** - Maps env vars to Bicep parameters

### Parameter Injection Pattern

```json
// infra/main.parameters.json
{
  "parameters": {
    "environmentName": { "value": "${AZURE_ENV_NAME}" },
    "location": { "value": "${AZURE_LOCATION=eastus2}" },
    "azureOpenAiEndpoint": { "value": "${AZURE_OPENAI_ENDPOINT}" }
  }
}
```

Syntax: `${VAR_NAME}` or `${VAR_NAME=default_value}`

### Setting Environment Variables

```bash
# Set for current environment
azd env set AZURE_OPENAI_ENDPOINT "https://my-openai.openai.azure.com"
azd env set AZURE_SEARCH_ENDPOINT "https://my-search.search.windows.net"

# Set during init
azd env new prod
azd env set AZURE_OPENAI_ENDPOINT "..." 
```

### Bicep Output → Environment Variable

```bicep
// In main.bicep - outputs auto-populate .azure/<env>/.env
output SERVICE_FRONTEND_URI string = frontend.outputs.uri
output SERVICE_BACKEND_URI string = backend.outputs.uri
output BACKEND_PRINCIPAL_ID string = backend.outputs.principalId
```

## Idempotent Deployments

### Why azd up is Idempotent

1. **Bicep is declarative** - Resources reconcile to desired state
2. **Remote builds tag uniquely** - Image tags include deployment timestamp
3. **ACR reuses layers** - Only changed layers upload

### Preserving Manual Changes

Custom domains added via Portal can be lost on redeploy. Preserve with hooks:

```yaml
hooks:
  preprovision:
    shell: sh
    run: |
      # Save custom domains before provision
      if az containerapp show --name "$FRONTEND_NAME" -g "$RG" &>/dev/null; then
        az containerapp show --name "$FRONTEND_NAME" -g "$RG" \
          --query "properties.configuration.ingress.customDomains" \
          -o json > /tmp/domains.json
      fi

  postprovision:
    shell: sh
    run: |
      # Verify/restore custom domains
      if [ -f /tmp/domains.json ]; then
        echo "Saved domains: $(cat /tmp/domains.json)"
      fi
```

### Handling Existing Resources

```bicep
// Reference existing ACR (don't recreate)
resource containerRegistry 'Microsoft.ContainerRegistry/registries@2023-07-01' existing = {
  name: containerRegistryName
}

// Set customDomains to null to preserve Portal-added domains
customDomains: empty(customDomainsParam) ? null : customDomainsParam
```

## Container App Service Discovery

Internal HTTP routing between Container Apps in same environment:

```bicep
// Backend reference in frontend env vars
env: [
  {
    name: 'BACKEND_URL'
    value: 'http://ca-backend-${resourceToken}'  // Internal DNS
  }
]
```

Frontend nginx proxies to internal URL:
```nginx
location /api {
    proxy_pass $BACKEND_URL;
}
```

## Managed Identity & RBAC

### Enable System-Assigned Identity

```bicep
resource containerApp 'Microsoft.App/containerApps@2024-03-01' = {
  identity: {
    type: 'SystemAssigned'
  }
}

output principalId string = containerApp.identity.principalId
```

### Post-Provision RBAC Assignment

```yaml
hooks:
  postprovision:
    shell: sh
    run: |
      PRINCIPAL_ID="${BACKEND_PRINCIPAL_ID}"
      
      # Azure OpenAI access
      az role assignment create \
        --assignee-object-id "$PRINCIPAL_ID" \
        --assignee-principal-type ServicePrincipal \
        --role "Cognitive Services OpenAI User" \
        --scope "$OPENAI_RESOURCE_ID" 2>/dev/null || true
      
      # Azure AI Search access
      az role assignment create \
        --assignee-object-id "$PRINCIPAL_ID" \
        --role "Search Index Data Reader" \
        --scope "$SEARCH_RESOURCE_ID" 2>/dev/null || true
```

## Common Commands

```bash
# Environment management
azd env list                        # List environments
azd env select <name>               # Switch environment
azd env get-values                  # Show all env vars
azd env set KEY value               # Set variable

# Deployment
azd up                              # Full provision + deploy
azd provision                       # Infrastructure only
azd deploy                          # Code deployment only
azd deploy --service backend        # Deploy single service

# Debugging
azd show                            # Show project status
az containerapp logs show -n <app> -g <rg> --follow  # Stream logs
```

## Reference Files

- **Bicep patterns**: See [references/bicep-patterns.md](references/bicep-patterns.md) for Container Apps modules
- **Troubleshooting**: See [references/troubleshooting.md](references/troubleshooting.md) for common issues
- **azure.yaml schema**: See [references/azure-yaml-schema.md](references/azure-yaml-schema.md) for full options

## Critical Reminders

1. **Always use `remoteBuild: true`** - Local builds fail on M1/ARM Macs deploying to AMD64
2. **Bicep outputs auto-populate .azure/<env>/.env** - Don't manually edit
3. **Use `azd env set` for secrets** - Not main.parameters.json defaults
4. **Service tags (`azd-service-name`)** - Required for azd to find Container Apps
5. **`|| true` in hooks** - Prevent RBAC "already exists" errors from failing deploy
```