fix(lab-05): align database lab with runtime behavior

This commit is contained in:
Luca Sacchi Ricciardi
2026-04-10 14:10:22 +00:00
parent 4b6777f600
commit 92c11d524f
7 changed files with 231 additions and 205 deletions
+9 -2
View File
@@ -4,12 +4,19 @@ Deploy PostgreSQL in rete privata con persistenza dati.
## Avvio del Laboratorio
Leggi prima i tutorial nell'ordine indicato sotto. Il flusso principale del lab usa `docker-compose.yml`; il `Dockerfile` e solo un riferimento per client e strumenti, non un prerequisito di avvio.
```bash
cd labs/lab-05-database
docker build .
docker compose up -d
```
## Ordine Consigliato
1. `tutorial/01-deploy-rds-database.md`
2. `tutorial/02-data-persistence.md`
3. `tutorial/03-security-compliance.md`
## Verifica Completamento
```bash
@@ -21,4 +28,4 @@ bash tests/99-final-verification.sh
- [Tutorial](tutorial/) - Guida passo-passo
- [How-to Guides](how-to-guides/) - Procedure specifiche
- [Reference](reference/) - Documentazione tecnica
- [Explanation](explanation/) - Paralleli cloud
- [Explanation](explanation/) - Paralleli cloud
@@ -5,7 +5,10 @@
### Da container nella stessa rete
```bash
docker exec lab05-app psql -h db -U lab05_user -d lab05_db
docker run --rm --network lab05-vpc-private \
-e PGPASSWORD=lab05_password \
postgres:16-alpine \
psql -h db -U lab05_user -d lab05_db
```
### Dall'host con port forwarding (non recommended)
@@ -43,13 +46,15 @@ postgresql://lab05_user:lab05_password@127.0.0.1:5432/lab05_db
Il database è in rete privata. Devi connetterti da container nella stessa rete:
```bash
# Prima entra in un container
docker exec -it lab05-app sh
# Poi connettiti
psql -h db -U lab05_user -d lab05_db
# Client temporaneo nella rete privata
docker run --rm -it --network lab05-vpc-private \
-e PGPASSWORD=lab05_password \
postgres:16-alpine \
psql -h db -U lab05_user -d lab05_db
```
Nota: il servizio `lab05-app` usa `nginx:alpine` e non include `psql`.
### Password authentication failed
Verifica le credenziali in docker-compose.yml:
@@ -8,8 +8,11 @@
# Connessione base
docker exec lab05-db psql -U lab05_user -d lab05_db
# Connessione con host specificato
docker exec lab05-app psql -h db -U lab05_user -d lab05_db
# Connessione da client nella rete privata
docker run --rm --network lab05-vpc-private \
-e PGPASSWORD=lab05_password \
postgres:16-alpine \
psql -h db -U lab05_user -d lab05_db
# Esegui comando singolo
docker exec lab05-db psql -U lab05_user -d lab05_db -c "SELECT version();"
+160 -153
View File
@@ -1,27 +1,49 @@
#!/bin/bash
# Lab 05 - Database & RDS
# Test 99: Final Verification (Double Check)
# Verifica finale end-to-end per studenti
set -euo pipefail
# Colori per output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
NC='\033[0m'
# Contatori
TEST_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
LAB_DIR="$(cd "$TEST_DIR/.." && pwd)"
pass_count=0
fail_count=0
skip_count=0
# Funzioni helper
inc_pass() { ((pass_count++)) || true; }
inc_fail() { ((fail_count++)) || true; }
inc_skip() { ((skip_count++)) || true; }
check_pass() {
echo -e "${GREEN}OK${NC}"
inc_pass
}
check_fail() {
echo -e "${RED}FAIL${NC}"
inc_fail
}
check_warn() {
echo -e "${YELLOW}WARN${NC} $1"
inc_skip
}
cleanup() {
docker compose down >/dev/null 2>&1 || true
}
trap cleanup EXIT
cd "$LAB_DIR"
echo "=========================================="
echo "Lab 05 - Final Verification (Double Check)"
echo "=========================================="
@@ -30,219 +52,204 @@ echo "Verifica completa: Lab 05 - Database & RDS"
echo "Parallelo: PostgreSQL in Docker ↔ RDS in AWS VPC"
echo ""
# Verifica file docker-compose.yml
echo -n "[CHECK] Verifica docker-compose.yml esista... "
if [ -f "docker-compose.yml" ]; then
echo -e "${GREEN}OK${NC}"
inc_pass
if [ -f docker-compose.yml ]; then
check_pass
else
echo -e "${RED}FAIL${NC}"
inc_fail
echo "ERRORE: docker-compose.yml non trovato"
exit 1
check_fail
exit 1
fi
echo -n "[CHECK] Sintassi docker compose valida... "
if docker compose config >/dev/null 2>&1; then
check_pass
else
check_fail
exit 1
fi
echo ""
echo "=== VERIFICA CONFIGURAZIONE ==="
# Verifica servizio database
echo -n "[CHECK] Servizio 'database' definito... "
if grep -q "database:" docker-compose.yml; then
echo -e "${GREEN}OK${NC}"
inc_pass
echo -n "[CHECK] Servizio 'db' definito... "
if grep -q '^ db:$' <(docker compose config); then
check_pass
else
echo -e "${RED}FAIL${NC}"
inc_fail
check_fail
fi
# Verifica immagine PostgreSQL
echo -n "[CHECK] Immagine PostgreSQL... "
if grep -q "image: postgres" docker-compose.yml; then
echo -e "${GREEN}OK${NC}"
inc_pass
if grep -q 'image: postgres:16-alpine' docker-compose.yml; then
check_pass
else
echo -e "${RED}FAIL${NC}"
inc_fail
check_fail
fi
# Verifica credenziali
echo -n "[CHECK] Credenziali PostgreSQL configurate... "
if grep -q "POSTGRES_DB:" docker-compose.yml && \
grep -q "POSTGRES_USER:" docker-compose.yml && \
grep -q "POSTGRES_PASSWORD:" docker-compose.yml; then
echo -e "${GREEN}OK${NC}"
inc_pass
if grep -q 'POSTGRES_DB:' docker-compose.yml && \
grep -q 'POSTGRES_USER:' docker-compose.yml && \
grep -q 'POSTGRES_PASSWORD:' docker-compose.yml; then
check_pass
else
echo -e "${RED}FAIL${NC}"
inc_fail
check_fail
fi
# Verifica volume
echo -n "[CHECK] Volume 'db-data' configurato... "
if grep -q "db-data:" docker-compose.yml; then
echo -e "${GREEN}OK${NC}"
inc_pass
if grep -q '^ db-data:$' <(docker compose config); then
check_pass
else
echo -e "${RED}FAIL${NC}"
inc_fail
check_fail
fi
# Verifica rete privata
echo -n "[CHECK] Database in rete 'vpc-private'... "
if grep -A 20 "database:" docker-compose.yml | grep -q "vpc-private"; then
echo -e "${GREEN}OK${NC}"
inc_pass
if docker compose config | grep -A 30 '^ db:$' | grep -q 'vpc-private'; then
check_pass
else
echo -e "${RED}FAIL${NC}"
inc_fail
check_fail
fi
# Verifica nessuna porta esposta
echo -n "[CHECK] NESSUNA porta esposta (INF-02)... "
if grep -A 30 "database:" docker-compose.yml | grep -q "ports:"; then
echo -e "${YELLOW}WARN${NC} (porte configurate - RDS non espone porte)"
inc_skip
echo -n "[CHECK] NESSUNA porta esposta sul database (INF-02)... "
if docker compose config | grep -A 30 '^ db:$' | grep -q 'ports:'; then
check_fail
else
echo -e "${GREEN}OK${NC}"
inc_pass
check_pass
fi
# Verifica limiti risorse
echo -n "[CHECK] Limiti risorse configurati (INF-03)... "
if grep -A 30 "database:" docker-compose.yml | grep -q "cpus:" && \
grep -A 30 "database:" docker-compose.yml | grep -q "memory:"; then
echo -e "${GREEN}OK${NC}"
inc_pass
echo -n "[CHECK] Limiti risorse configurati sul database (INF-03)... "
if docker compose config | grep -A 30 '^ db:$' | grep -q 'cpus:' && \
docker compose config | grep -A 30 '^ db:$' | grep -q 'memory:'; then
check_pass
else
echo -e "${RED}FAIL${NC}"
inc_fail
check_fail
fi
echo ""
echo "=== VERIFICA ESECUZIONE ==="
# Verifica container in esecuzione
docker compose down >/dev/null 2>&1 || true
docker compose up -d >/dev/null
sleep 10
echo -n "[CHECK] Container 'lab05-db' in esecuzione... "
if docker ps --format '{{{{Names}}}}' | grep -q "^lab05-db$"; then
echo -e "${GREEN}OK${NC}"
inc_pass
if docker ps --format '{{.Names}}' | grep -q '^lab05-db$'; then
check_pass
else
echo -e "${RED}FAIL${NC}"
inc_fail
echo "Avviare i container: docker compose up -d"
echo ""
echo "Risultato: $pass_count PASS, $fail_count FAIL, $skip_count SKIP"
exit 1
check_fail
echo "Avviare i container: docker compose up -d"
exit 1
fi
# Verifica healthcheck
echo -n "[CHECK] Healthcheck configurato... "
health_status=$(docker inspect lab05-db --format '{{.State.Health.Status}}' 2>/dev/null || echo "unknown")
if [ "$health_status" != "unknown" ]; then
echo -e "${GREEN}OK${NC} ($health_status)"
inc_pass
echo -n "[CHECK] Healthcheck database... "
health_status=$(docker inspect lab05-db --format '{{.State.Health.Status}}' 2>/dev/null || echo unknown)
if [ "$health_status" = "healthy" ]; then
check_pass
elif [ "$health_status" = "starting" ]; then
check_warn "(database ancora in avvio)"
else
echo -e "${YELLOW}WARN${NC} (nessun healthcheck)"
inc_skip
check_fail
fi
# Verifica pg_isready
echo -n "[CHECK] PostgreSQL pronto (pg_isready)... "
if docker exec lab05-db pg_isready &>/dev/null; then
echo -e "${GREEN}OK${NC}"
inc_pass
if docker exec lab05-db pg_isready -U lab05_user >/dev/null 2>&1; then
check_pass
else
echo -e "${YELLOW}WARN${NC} (PostgreSQL non ancora pronto)"
inc_skip
check_fail
fi
echo ""
echo "=== VERIFICA SICUREZZA ==="
# INF-01: Non-root
echo -n "[CHECK] Container NON gira come root (INF-01)... "
container_user=$(docker exec lab05-db whoami 2>/dev/null || echo "unknown")
if [ "$container_user" = "postgres" ]; then
echo -e "${GREEN}OK${NC} ($container_user)"
inc_pass
echo -n "[CHECK] Processo principale NON gira come root (INF-01)... "
pid1_user=$(docker exec lab05-db sh -c "ps -o user,pid,args | awk '\$2 == 1 {print \$1}'" 2>/dev/null | tr -d '[:space:]')
pid1_uid=$(docker exec lab05-db sh -c "awk '/^Uid:/ {print \$2}' /proc/1/status" 2>/dev/null | tr -d '[:space:]')
if [ -n "$pid1_uid" ] && [ "$pid1_uid" -ne 0 ]; then
echo -e "${GREEN}OK${NC} ($pid1_user uid=$pid1_uid)"
inc_pass
else
echo -e "${RED}FAIL${NC} ($container_user)"
inc_fail
check_fail
fi
# INF-02: No host ports
echo -n "[CHECK] NESSUNA porta su host (INF-02)... "
db_port=$(docker port lab05-db 5432 2>/dev/null || echo "")
echo -n "[CHECK] NESSUNA porta host sul DB (INF-02)... "
db_port=$(docker port lab05-db 5432 2>/dev/null || true)
if [ -z "$db_port" ]; then
echo -e "${GREEN}OK${NC}"
inc_pass
check_pass
else
echo -e "${RED}FAIL${NC} (porta $db_port)"
inc_fail
echo -e "${RED}FAIL${NC} ($db_port)"
inc_fail
fi
echo -n "[CHECK] Isolamento rete pubblica -> DB... "
if docker exec lab05-test-public ping -c 1 db >/dev/null 2>&1; then
check_fail
else
check_pass
fi
echo -n "[CHECK] App privata puo raggiungere DB... "
if docker exec lab05-app ping -c 1 db >/dev/null 2>&1; then
check_pass
else
check_fail
fi
# INF-03: Resource limits
echo -n "[CHECK] Limiti risorsa applicati (INF-03)... "
if docker inspect lab05-db --format '{{.HostConfig.Memory}}' | grep -q "[1-9]"; then
echo -e "${GREEN}OK${NC}"
inc_pass
db_memory=$(docker inspect lab05-db --format '{{.HostConfig.Memory}}' 2>/dev/null || echo 0)
db_cpus=$(docker inspect lab05-db --format '{{.HostConfig.NanoCpus}}' 2>/dev/null || echo 0)
if [ "$db_memory" -gt 0 ] && [ "$db_cpus" -gt 0 ]; then
check_pass
else
echo -e "${RED}FAIL${NC}"
inc_fail
check_fail
fi
# INF-04: Volume persistence
echo -n "[CHECK] Volume persistenza (INF-04)... "
if docker volume ls --format '{{{{.Name}}}}' | grep -q "^lab05_db-data$"; then
echo -e "${GREEN}OK${NC}"
inc_pass
echo -n "[CHECK] Volume persistenza presente (INF-04)... "
if docker volume ls --format '{{.Name}}' | grep -q '^lab-05-database_db-data$'; then
check_pass
else
echo -e "${RED}FAIL${NC}"
inc_fail
check_fail
fi
echo ""
echo "=== VERIFICA FUNZIONALITÀ ==="
echo "=== VERIFICA FUNZIONALITA ==="
# Test connessione database
echo -n "[CHECK] Connessione database funziona... "
if docker exec lab05-db psql -U lab05_user -d lab05_db -c "SELECT 1;" &>/dev/null; then
echo -e "${GREEN}OK${NC}"
inc_pass
if docker exec lab05-db psql -U lab05_user -d lab05_db -c 'SELECT 1;' >/dev/null 2>&1; then
check_pass
else
echo -e "${RED}FAIL${NC}"
inc_fail
check_fail
fi
# Test creazione tabella
echo -n "[CHECK] Creazione tabella... "
if docker exec lab05-db psql -U lab05_user -d lab05_db -c "CREATE TABLE IF NOT EXISTS verify_test (id SERIAL);" &>/dev/null; then
echo -e "${GREEN}OK${NC}"
inc_pass
if docker exec lab05-db psql -U lab05_user -d lab05_db -c 'CREATE TABLE IF NOT EXISTS verify_test (id SERIAL PRIMARY KEY, note TEXT);' >/dev/null 2>&1; then
check_pass
else
echo -e "${RED}FAIL${NC}"
inc_fail
check_fail
fi
# Test inserimento dati
echo -n "[CHECK] Inserimento dati... "
if docker exec lab05-db psql -U lab05_user -d lab05_db -c "INSERT INTO verify_test DEFAULT VALUES;" &>/dev/null; then
echo -e "${GREEN}OK${NC}"
inc_pass
if docker exec lab05-db psql -U lab05_user -d lab05_db -c "INSERT INTO verify_test (note) VALUES ('ok');" >/dev/null 2>&1; then
check_pass
else
echo -e "${RED}FAIL${NC}"
inc_fail
check_fail
fi
# Test query dati
echo -n "[CHECK] Query dati... "
count=$(docker exec lab05-db psql -U lab05_user -d lab05_db -t -c "SELECT COUNT(*) FROM verify_test;" 2>/dev/null | tr -d ' ')
if [ -n "$count" ] && [ "$count" -gt 0 ]; then
echo -e "${GREEN}OK${NC} ($count righe)"
inc_pass
count=$(docker exec lab05-db psql -U lab05_user -d lab05_db -tAc "SELECT COUNT(*) FROM verify_test WHERE note='ok';" 2>/dev/null | tr -d '[:space:]')
if [ -n "$count" ] && [ "$count" -ge 1 ]; then
echo -e "${GREEN}OK${NC} ($count righe)"
inc_pass
else
echo -e "${RED}FAIL${NC}"
inc_fail
check_fail
fi
echo -n "[CHECK] Persistenza dati dopo restart DB... "
docker compose restart db >/dev/null
sleep 8
persist_count=$(docker exec lab05-db psql -U lab05_user -d lab05_db -tAc "SELECT COUNT(*) FROM verify_test WHERE note='ok';" 2>/dev/null | tr -d '[:space:]')
if [ -n "$persist_count" ] && [ "$persist_count" -ge 1 ]; then
echo -e "${GREEN}OK${NC} ($persist_count righe)"
inc_pass
else
check_fail
fi
echo ""
@@ -253,20 +260,20 @@ echo " $fail_count FAIL"
echo " $skip_count SKIP"
echo "=========================================="
if [ $fail_count -eq 0 ]; then
echo ""
echo -e "${GREEN}✓ LAB 05 COMPLETATO CON SUCCESSO${NC}"
echo ""
echo "Paralleli confermati:"
echo " PostgreSQL container → RDS Instance"
echo " Private network → VPC Private Subnet"
echo " Named volume → EBS Volume"
echo " Resource limits → DB Instance Class"
echo ""
exit 0
if [ "$fail_count" -eq 0 ]; then
echo ""
echo -e "${GREEN}✓ LAB 05 COMPLETATO CON SUCCESSO${NC}"
echo ""
echo "Paralleli confermati:"
echo " PostgreSQL container → RDS Instance"
echo " Private network → VPC Private Subnet"
echo " Named volume → EBS Volume"
echo " Resource limits → DB Instance Class"
echo ""
exit 0
else
echo ""
echo -e "${RED}✗ LAB 05 HA ERRORI - RISOLVERE E RIPETERE${NC}"
echo ""
exit 1
echo ""
echo -e "${RED}✗ LAB 05 HA ERRORI - RISOLVERE E RIPETERE${NC}"
echo ""
exit 1
fi
@@ -16,20 +16,20 @@ Deployare PostgreSQL in Docker private network che simula RDS in VPC privata AWS
## Passo 1: Verifica l'ambiente
Verifica che le reti private siano già state create.
Il compose di questo lab crea da solo le reti `lab05-vpc-public` e `lab05-vpc-private`. Lab 02 resta un prerequisito concettuale, non una dipendenza runtime.
Esegui:
```bash
# Verifica reti esistenti
docker network ls | grep vpc
# Verifica servizi e reti definiti nel compose
docker compose config --services
docker compose config | grep -A 20 "networks:"
# Atteso:
# lab05-vpc-private
# lab05-vpc-public
# app
# db
# test-public
```
Se le reti non esistono, consulta prima il Lab 02.
---
## Passo 2: Esamina docker-compose.yml
@@ -109,10 +109,13 @@ Atteso: `healthy` o `accepting connections`
Puoi connetterti SOLO da container nella stessa rete privata.
Esegui dal container `app`:
Esegui da un client PostgreSQL temporaneo collegato alla rete privata:
```bash
# Connettiti dal container app
docker exec lab05-app psql -h db -U lab05_user -d lab05_db
# Connettiti da un client nella stessa rete privata
docker run --rm --network lab05-vpc-private \
-e PGPASSWORD=lab05_password \
postgres:16-alpine \
psql -h db -U lab05_user -d lab05_db
# Una volta connesso, esegui:
lab05_db=> SELECT version();
@@ -163,8 +166,7 @@ Esegui lo script di verifica finale.
Esegui:
```bash
cd tests
./99-final-verification.sh
bash tests/99-final-verification.sh
```
Tutti i test devono PASSARE.
@@ -24,10 +24,10 @@ Esegui:
docker volume ls | grep db-data
# Atteso:
# local lab05_db-data
# local lab-05-database_db-data
```
Il volume è nominativo (`local` driver), quindi i dati sopravvivono.
Il volume e nominativo (`local` driver), quindi i dati sopravvivono. Nel repository il nome reale include il prefisso del progetto compose: `lab-05-database_db-data`.
---
@@ -142,10 +142,10 @@ Esplora il volume per capire come PostgreSQL memorizza i dati.
Esegui:
```bash
# Trova il mount point del volume
docker inspect lab05-db --format '{{range .Mounts}}{{if eq .Destination "/var/lib/postgresql/data"}}{{.Source}}{{end}}{{end}}'
docker volume inspect lab-05-database_db-data --format '{{.Mountpoint}}'
# Lista file nel volume (come root)
sudo ls -la /var/lib/docker/volumes/lab05_db-data/_data/
sudo ls -la $(docker volume inspect lab-05-database_db-data --format '{{.Mountpoint}}')
```
Struttura chiave:
@@ -215,7 +215,7 @@ Tutte le verifiche devono passare.
### Dati persi dopo riavvio
```bash
# Verifica che il volume sia nominativo
docker volume inspect lab05_db-data
docker volume inspect lab-05-database_db-data
# Verifica montaggio corretto
docker inspect lab05-db --format '{{json .Mounts}}' | jq
@@ -226,17 +226,17 @@ docker inspect lab05-db --format '{{json .Mounts}}' | jq
# Lista tutti i volumi
docker volume ls
# Se il volume non esiste, ricrea
docker volume create lab05_db-data
# Se il volume non esiste, ricrealo rialzando il compose
docker compose up -d
```
### Permesso negato su volume
```bash
# Verifica proprietà volume
sudo ls -la /var/lib/docker/volumes/lab05_db-data/
sudo ls -la $(docker volume inspect lab-05-database_db-data --format '{{.Mountpoint}}')
# PostgreSQL deve poter scrivere
sudo chown -R 999:999 /var/lib/docker/volumes/lab05_db-data/
sudo chown -R 999:999 $(docker volume inspect lab-05-database_db-data --format '{{.Mountpoint}}')
```
---
@@ -19,21 +19,21 @@ PostgreSQL official image NON gira come root.
Esegui:
```bash
# Verifica utente nel container
docker exec lab05-db whoami
# Verifica l'utente del processo principale (PID 1)
docker exec lab05-db sh -c "ps -o user,pid,args | awk '\$2 == 1 {print \$1, \$2, \$3}'"
# Atteso: postgres
# Atteso: postgres 1 postgres
```
Verifica UID:
```bash
# Verifica UID != 0
docker exec lab05-db id -u
# Verifica UID del processo principale != 0
docker exec lab05-db sh -c "awk '/^Uid:/ {print \$2}' /proc/1/status"
# Atteso: 999 (postgres user UID)
# Atteso: un valore non-zero (nel lab osservato: 70)
```
Se l'utente è `root` o UID `0`, c'è una violazione di sicurezza.
Nota: `docker exec ... whoami` puo mostrare `root` per la shell di debug lanciata con `exec`, ma non rappresenta il processo principale del database. Per INF-01 devi controllare il processo PID 1.
---
@@ -62,8 +62,14 @@ Test isolamento:
# Prova connessione dall'host (DEVE fallire)
psql -h localhost -U lab05_user -d lab05_db 2>&1 || echo "Corretto: non accessibile"
# Prova connessione da container app (DEVE successo)
docker exec lab05-app psql -h db -U lab05_user -d lab05_db -c "SELECT 1;"
# Prova reachability dal container app (DEVE riuscire)
docker exec lab05-app ping -c 2 db
# Prova query SQL da un client nella rete privata (DEVE riuscire)
docker run --rm --network lab05-vpc-private \
-e PGPASSWORD=lab05_password \
postgres:16-alpine \
psql -h db -U lab05_user -d lab05_db -c "SELECT 1;"
```
---
@@ -104,13 +110,13 @@ I dati devono persistere in volume nominativo.
Esegui:
```bash
# Verifica volume esista
docker volume ls | grep lab05_db-data
docker volume ls | grep lab-05-database_db-data
# Verifica montaggio
docker inspect lab05-db --format '{{range .Mounts}}{{if eq .Destination "/var/lib/postgresql/data"}}{{.Name}}{{end}}{{end}}'
```
Atteso: `lab05_db-data`
Atteso: `lab-05-database_db-data`
---
@@ -120,11 +126,10 @@ Esegui lo script di verifica sicurezza.
Esegui:
```bash
cd tests
./04-security-test.sh
bash tests/99-final-verification.sh
```
Tutti i test devono PASSARE.
Lo script finale copre anche i controlli di sicurezza principali del lab.
---
@@ -205,8 +210,7 @@ Esegui la verifica finale completa.
Esegui:
```bash
cd tests
./99-final-verification.sh
bash tests/99-final-verification.sh
```
Tutti i test devono PASSARE, inclusi:
@@ -249,11 +253,9 @@ Prima di passare al production (simulato):
### Container gira come root
```bash
# Verifica image
docker inspect lab05-db --format '{{.Config.User}}'
# PostgreSQL official image deve usare 'postgres'
# Se root, controlla Dockerfile
# Verifica il processo principale, non la shell lanciata con docker exec
docker exec lab05-db sh -c "ps -o user,pid,args | awk '\$2 == 1 {print \$1, \$2, \$3}'"
docker exec lab05-db sh -c "awk '/^Uid:/ {print \$2}' /proc/1/status"
```
### Database accessibile dall'host