23a9ffe443
Phase Plans (5 files): - 04-RESEARCH.md: Domain research on Docker limits, healthchecks, EC2 parallels - 04-VALIDATION.md: Success criteria and validation strategy - 04-01-PLAN.md: Test infrastructure (RED phase) - 04-02-PLAN.md: Diátxis documentation - 04-03-PLAN.md: Infrastructure implementation (GREEN phase) Test Scripts (6 files, 1300+ lines): - 01-resource-limits-test.sh: Validate INF-03 compliance - 02-healthcheck-test.sh: Validate healthcheck configuration - 03-enforcement-test.sh: Verify resource limits with docker stats - 04-verify-infrastructure.sh: Infrastructure verification - 99-final-verification.sh: End-to-end student verification - run-all-tests.sh: Test orchestration with fail-fast - quick-test.sh: Fast validation (<30s) Documentation (11 files, 2500+ lines): Tutorials (3): - 01-set-resource-limits.md: EC2 instance types, Docker limits syntax - 02-implement-healthchecks.md: ELB health check parallels - 03-dependencies-with-health.md: depends_on with service_healthy How-to Guides (4): - check-resource-usage.md: docker stats monitoring - test-limits-enforcement.md: Stress testing CPU/memory - custom-healthcheck.md: HTTP, TCP, database healthchecks - instance-type-mapping.md: Docker limits → EC2 mapping Reference (3): - compose-resources-syntax.md: Complete deploy.resources reference - healthcheck-syntax.md: All healthcheck parameters - ec2-instance-mapping.md: Instance type mapping table Explanation (1): - compute-ec2-parallels.md: Container=EC2, Limits=Instance Type, Healthcheck=ELB Infrastructure: - docker-compose.yml: 5 services (web, app, worker, db, stress-test) All services: INF-03 compliant (cpus + memory limits) All services: healthcheck configured EC2 parallels: t2.nano, t2.micro, t2.small, t2.medium, m5.large - Dockerfile: Alpine 3.19 + stress tools + non-root user Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
194 lines
3.6 KiB
Markdown
194 lines
3.6 KiB
Markdown
# Reference: Docker Compose Healthcheck Syntax
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Riferimento completo per la configurazione degli healthchecks.
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## Sezione healthcheck
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### Struttura Completa
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```yaml
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services:
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service_name:
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healthcheck:
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test: ["CMD", "command", "arg1", "arg2"]
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interval: 30s
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timeout: 30s
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retries: 3
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start_period: 0s
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```
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## Parametri
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### test (Required)
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Comando da eseguire per verificare la salute.
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**Formato CMD:**
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```yaml
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test: ["CMD", "wget", "--spider", "-q", "http://localhost/health"]
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```
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**Formato CMD-SHELL:**
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```yaml
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test: ["CMD-SHELL", "curl -f http://localhost/ || exit 1"]
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```
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**Formato NONE:**
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```yaml
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test: ["NONE"]
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```
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Disabilita healthcheck ereditato dall'immagine.
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### interval
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Frequenza di esecuzione del test.
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```yaml
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interval: 5s # Ogni 5 secondi
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interval: 10s # Ogni 10 secondi
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interval: 30s # Ogni 30 secondi (default)
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interval: 1m # Ogni minuto
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```
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**Validità:**
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- Minimo: `1s` (1 secondo)
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- Massimo: Nessuno
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- Default: `30s`
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### timeout
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Tempo massimo per completare il test.
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```yaml
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timeout: 2s # 2 secondi
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timeout: 5s # 5 secondi (default)
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timeout: 30s # 30 secondi
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```
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**Nota:** Se il test supera il timeout, conta come fallimento.
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### retries
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Numero di fallimenti consecutivi prima di marcare unhealthy.
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```yaml
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retries: 1 # 1 fallimento = unhealthy
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retries: 3 # 3 fallimenti = unhealthy (default)
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retries: 5 # 5 fallimenti = unhealthy
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```
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**Calcolo del tempo unhealthy:**
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```
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tempo_totale = (interval + timeout) × retries
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```
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Esempio con `interval: 10s, timeout: 5s, retries: 3`:
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- Check 1: 0s - 5s
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- Check 2: 10s - 15s
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- Check 3: 20s - 25s
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- Unhealthy dopo: 25s
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### start_period
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Grace period prima di contare retries verso unhealthy.
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```yaml
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start_period: 0s # Nessun grace period (default)
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start_period: 5s # 5 secondi di grace
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start_period: 10s # 10 secondi di grace
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start_period: 30s # 30 secondi di grace
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```
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**Comportamento:**
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- Durante `start_period`: Fallimenti non contano
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- Dopo `start_period`: `retries` inizi a contare
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## Esempi per Tipo di Servizio
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### HTTP Service (Nginx)
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```yaml
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healthcheck:
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test: ["CMD", "wget", "--quiet", "--tries=1", "--spider", "http://localhost/"]
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interval: 10s
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timeout: 5s
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retries: 3
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start_period: 5s
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```
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### Database (PostgreSQL)
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```yaml
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healthcheck:
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test: ["CMD-SHELL", "pg_isready -U postgres || exit 1"]
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interval: 10s
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timeout: 5s
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retries: 5
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start_period: 10s
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```
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### Cache (Redis)
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```yaml
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healthcheck:
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test: ["CMD", "redis-cli", "ping"]
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interval: 10s
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timeout: 3s
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retries: 3
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```
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### TCP Connection
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```yaml
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healthcheck:
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test: ["CMD-SHELL", "nc -z localhost 8080 || exit 1"]
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interval: 15s
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timeout: 2s
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retries: 3
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```
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### File Check
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```yaml
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healthcheck:
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test: ["CMD-SHELL", "test -f /tmp/ready || exit 1"]
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interval: 5s
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timeout: 1s
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retries: 5
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```
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## Stati di Salute
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### Ciclo di Vita
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```
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created → starting → healthy
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↓
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unhealthy
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```
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**Transizioni:**
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| Da | A | Condizione |
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|----|---|------------|
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| created | starting | Container avviato con healthcheck |
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| starting | healthy | `retries` consecutivi passano |
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| starting | unhealthy | `retries` consecutivi falliscono (dopo start_period) |
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| healthy | unhealthy | `retries` consecutivi falliscono |
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| unhealthy | healthy | 1 check passa |
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### Ispezionare Stato
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```bash
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# Stato corrente
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docker inspect lab03-web --format '{{.State.Health.Status}}'
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# Output: healthy / unhealthy / starting
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# Exit code dell'ultimo check
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docker inspect lab03-web --format '{{.State.Health.ExitCode}}'
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# Output: 0 (success) o !0 (failure)
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### Vedi Anche
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- Tutorial: Implementare Healthchecks
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- How-to: Custom Healthcheck
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