# ──────────────────────────────────────────────────────────────────────────
# postgresql/cutover/postgresql-ha-final.yaml — ADR-0001 Phase 3, Stage 3
#
# Deployed by cutover.sh (Phase 7) as an UPDATE to the SAME "postgresqlha"
# stack that postgresql-ha-staging.yaml created in Stage 2:
#   docker stack deploy -c postgresql/cutover/postgresql-ha-final.yaml postgresqlha
#
# ⚠️  Do NOT deploy this before Patroni has been genuinely promoted
#     (cutover.sh Phase 5) and confirmed healthy (Phase 6). Deploying it
#     earlier adds the postgresql/db aliases to a backend HAProxy's own
#     healthcheck (GET /primary) will correctly report as unhealthy (a
#     standby_leader is read-only, not a real primary) — any client that
#     Swarm's round-robin DNS routes to HAProxy during that window would
#     hit zero healthy servers and fail outright. See RUNBOOK.md for the
#     full rationale on phase ordering.
#
# What changed vs. postgresql-ha-staging.yaml (Stage 2):
#   - etcd-1/2/3 and patroni-0/patroni-1 service specs are BYTE-IDENTICAL
#     to the staging file, deliberately. `docker stack deploy` diffs each
#     service's spec independently — since these five specs are unchanged,
#     Swarm will NOT recreate/restart them. This matters enormously here:
#     patroni-1 is the live, newly-promoted PRIMARY carrying real
#     production traffic by the time this file is deployed, and
#     patroni-0 is its live replica. Neither may be disrupted by this
#     step. Only the haproxy service (below) has a spec change, so only
#     it gets updated.
#   - haproxy service: adds `postgresql` and `db` as network aliases on
#     postgresql_db-backend — this is the actual DNS cutover mechanism.
#     Still deliberately WITHOUT the external port publish (5430) or
#     traefik_backend network/labels that the STEADY-STATE production
#     postgresql.yaml's haproxy block eventually needs — taking over
#     that external/Traefik-SNI path is a documented MANUAL, POST-cutover
#     step (see RUNBOOK.md "Post-cutover follow-up"), not part of this
#     automated procedure. Confirmed with the operator: no external
#     consumer depends on port 5430 during the cutover window, so this
#     is deferred deliberately, not an oversight.
#   - Uses the same postgresql/haproxy.cfg already committed to git
#     (Patroni-aware TCP router, GET /primary healthcheck, no changes
#     needed for this stage).
#
# Once this is live and all consumers have verified (cutover.sh Phase 9),
# legacy is scaled to 0 (Phase 10) and this becomes the sole answer for
# the `postgresql`/`db` names on postgresql_db-backend.
# ──────────────────────────────────────────────────────────────────────────
version: "3.6"

services:

  etcd-1:
    image: quay.io/coreos/etcd:v3.5.9
    hostname: etcd-1
    command:
      - etcd
      - --name=etcd-1
      - --data-dir=/etcd-data
      - --initial-advertise-peer-urls=http://etcd-1:2380
      - --listen-peer-urls=http://0.0.0.0:2380
      - --listen-client-urls=http://0.0.0.0:2379
      - --advertise-client-urls=http://etcd-1:2379
      - --initial-cluster=etcd-1=http://etcd-1:2380,etcd-2=http://etcd-2:2380,etcd-3=http://etcd-3:2380
      - --initial-cluster-state=new
      - --initial-cluster-token=postgresql-ha-etcd
    volumes:
      - /volume1/docker/PostgreSQL/etcd-1-data:/etcd-data
    networks:
      - postgresql_db-backend
    deploy:
      placement:
        constraints:
          - node.hostname == docker-1

  etcd-2:
    image: quay.io/coreos/etcd:v3.5.9
    hostname: etcd-2
    command:
      - etcd
      - --name=etcd-2
      - --data-dir=/etcd-data
      - --initial-advertise-peer-urls=http://etcd-2:2380
      - --listen-peer-urls=http://0.0.0.0:2380
      - --listen-client-urls=http://0.0.0.0:2379
      - --advertise-client-urls=http://etcd-2:2379
      - --initial-cluster=etcd-1=http://etcd-1:2380,etcd-2=http://etcd-2:2380,etcd-3=http://etcd-3:2380
      - --initial-cluster-state=new
      - --initial-cluster-token=postgresql-ha-etcd
    volumes:
      - /volume1/docker/PostgreSQL/etcd-2-data:/etcd-data
    networks:
      - postgresql_db-backend
    deploy:
      placement:
        constraints:
          - node.hostname == docker-2

  etcd-3:
    image: quay.io/coreos/etcd:v3.5.9
    hostname: etcd-3
    command:
      - etcd
      - --name=etcd-3
      - --data-dir=/etcd-data
      - --initial-advertise-peer-urls=http://etcd-3:2380
      - --listen-peer-urls=http://0.0.0.0:2380
      - --listen-client-urls=http://0.0.0.0:2379
      - --advertise-client-urls=http://etcd-3:2379
      - --initial-cluster=etcd-1=http://etcd-1:2380,etcd-2=http://etcd-2:2380,etcd-3=http://etcd-3:2380
      - --initial-cluster-state=new
      - --initial-cluster-token=postgresql-ha-etcd
    volumes:
      - /volume1/docker/PostgreSQL/etcd-3-data:/etcd-data
    networks:
      - postgresql_db-backend
    deploy:
      placement:
        constraints:
          - node.hostname == docker-3

  patroni-0:
    image: ghcr.io/zalando/spilo-17:4.0-p3
    hostname: patroni-0
    command:
      - /bin/sh
      - -c
      - |
        export PGPASSWORD_SUPERUSER="$$(cat /run/secrets/postgresql_password)"
        export PGPASSWORD_STANDBY="$$(cat /run/secrets/postgresql_replication_password)"
        export PATRONI_RESTAPI_PASSWORD="$$(cat /run/secrets/postgresql_patroni_password)"
        mkdir -p /scripts
        cat > /scripts/post_init_wrapper.sh <<'WRAP'
        #!/bin/bash
        set -e
        psql -d "$$2" -v ON_ERROR_STOP=1 -c 'DO $$do$$ BEGIN IF NOT EXISTS (SELECT 1 FROM pg_catalog.pg_roles WHERE rolname = $$x$$postgres$$x$$) THEN CREATE ROLE postgres WITH SUPERUSER NOLOGIN; END IF; END $$do$$;'
        exec /scripts/post_init.sh "$$@"
        WRAP
        chmod +x /scripts/post_init_wrapper.sh
        exec /bin/sh /launch.sh init
    environment:
      SCOPE: postgres-ha
      PATRONI_NAME: patroni-0
      ETCD3_HOSTS: '"etcd-1:2379","etcd-2:2379","etcd-3:2379"'
      PGUSER_SUPERUSER: PGadmin
      PGUSER_STANDBY: standby
      PATRONI_RESTAPI_USERNAME: patroni
      PGROOT: /home/postgres/pgdata/pgroot
      SPILO_CONFIGURATION: |
        bootstrap:
          post_init: /scripts/post_init_wrapper.sh "zalandos"
          dcs:
            standby_cluster:
              host: postgresql
              port: 5432
              create_replica_methods:
              - basebackup_fast_xlog
    secrets:
      - postgresql_password
      - postgresql_replication_password
      - postgresql_patroni_password
    volumes:
      - /volume1/docker/PostgreSQL/patroni-0-data:/home/postgres/pgdata
    networks:
      - postgresql_db-backend
    deploy:
      placement:
        constraints:
          - node.labels.pg-role == primary

  patroni-1:
    image: ghcr.io/zalando/spilo-17:4.0-p3
    hostname: patroni-1
    command:
      - /bin/sh
      - -c
      - |
        export PGPASSWORD_SUPERUSER="$$(cat /run/secrets/postgresql_password)"
        export PGPASSWORD_STANDBY="$$(cat /run/secrets/postgresql_replication_password)"
        export PATRONI_RESTAPI_PASSWORD="$$(cat /run/secrets/postgresql_patroni_password)"
        mkdir -p /scripts
        cat > /scripts/post_init_wrapper.sh <<'WRAP'
        #!/bin/bash
        set -e
        psql -d "$$2" -v ON_ERROR_STOP=1 -c 'DO $$do$$ BEGIN IF NOT EXISTS (SELECT 1 FROM pg_catalog.pg_roles WHERE rolname = $$x$$postgres$$x$$) THEN CREATE ROLE postgres WITH SUPERUSER NOLOGIN; END IF; END $$do$$;'
        exec /scripts/post_init.sh "$$@"
        WRAP
        chmod +x /scripts/post_init_wrapper.sh
        exec /bin/sh /launch.sh init
    environment:
      SCOPE: postgres-ha
      PATRONI_NAME: patroni-1
      ETCD3_HOSTS: '"etcd-1:2379","etcd-2:2379","etcd-3:2379"'
      PGUSER_SUPERUSER: PGadmin
      PGUSER_STANDBY: standby
      PATRONI_RESTAPI_USERNAME: patroni
      PGROOT: /home/postgres/pgdata/pgroot
      SPILO_CONFIGURATION: |
        bootstrap:
          post_init: /scripts/post_init_wrapper.sh "zalandos"
          dcs:
            standby_cluster:
              host: postgresql
              port: 5432
              create_replica_methods:
              - basebackup_fast_xlog
    secrets:
      - postgresql_password
      - postgresql_replication_password
      - postgresql_patroni_password
    volumes:
      - /volume1/docker/PostgreSQL/patroni-1-data:/home/postgres/pgdata
    networks:
      - postgresql_db-backend
    deploy:
      placement:
        constraints:
          - node.labels.pg-role == replica

  # ── Final-stage HAProxy: takes over the postgresql/db aliases ──────────
  # Internal Swarm-DNS only at this stage — no published port, no
  # traefik_backend network/labels. External access (port 5430 /
  # Traefik SNI) is a deliberate, documented MANUAL post-cutover step,
  # not part of this automated procedure — confirmed no external
  # consumer depends on it during the cutover window.
  haproxy:
    image: haproxy:2.9-alpine
    hostname: haproxy
    volumes:
      - /volume1/docker/compose-files/postgresql/haproxy.cfg:/usr/local/etc/haproxy/haproxy.cfg:ro
    networks:
      postgresql_db-backend:
        aliases:
          - postgresql
          - db
    deploy:
      mode: global

networks:
  postgresql_db-backend:
    external: true

secrets:
  postgresql_password:
    external: true
  postgresql_replication_password:
    external: true
  postgresql_patroni_password:
    external: true