# syntax=docker/dockerfile:1
# =============================================================================
# Multi-stage Dockerfile for pg_trickle E2E integration tests.
#
# Stage 1 (builder): Compiles the extension from source.
# Stage 2 (runtime): Copies the compiled artifacts into a clean postgres:18.3.
#
# Usage:
#   # Fast build — uses pre-built builder image (Rust + cargo-pgrx pre-baked):
#   just build-builder-image   # once, ~7 min; skip if already built
#   just build-e2e-image       # ~2-3 min cold, ~30s warm
#
#   # Self-contained build (no pre-built builder, downloads everything, ~10 min):
#   BUILDER_IMAGE=postgres:18.3 just build-e2e-image
#
# The build context must be the project root (parent of tests/).
#
# Speed notes:
#   When BUILDER_IMAGE=pg_trickle_builder:pg18 (default), Rust + cargo-pgrx
#   + pgrx init are already baked in.  Stage 1 only runs cargo fetch and
#   cargo pgrx package (~2-3 min cold; ~30s warm with BuildKit cache mounts).
#   BuildKit --mount=type=cache persists the cargo registry and incremental
#   compile artefacts between builds on the same Docker host.
# =============================================================================

# ── Stage 1: Build the extension ────────────────────────────────────────────
# Default to the pre-built builder image (see tests/Dockerfile.builder).
# Override with BUILDER_IMAGE=postgres:18.3 for a self-contained build.
ARG BUILDER_IMAGE=pg_trickle_builder:pg18
FROM ${BUILDER_IMAGE} AS builder

# ── Dependency caching layer ────────────────────────────────────────────────
# Copy manifests + lockfile so dep downloads are cached separately from source.
WORKDIR /build
COPY Cargo.toml Cargo.lock ./

# Create minimal stubs so cargo can resolve the workspace without real source.
RUN mkdir -p src/bin src/dvm/operators benches && \
    echo '#![allow(warnings)] fn main() {}' > src/bin/pgrx_embed.rs && \
    echo '#![allow(warnings)]' > src/lib.rs && \
    echo '' > src/dvm/mod.rs && \
    echo '' > src/dvm/operators/mod.rs && \
    echo '' > src/ivm.rs && \
    echo 'fn main() {}' > benches/refresh_bench.rs && \
    echo 'fn main() {}' > benches/diff_operators.rs

# Pre-fetch all crates.  Cache mount keeps the registry between builds so
# this becomes a no-op when Cargo.lock hasn't changed.
RUN --mount=type=cache,target=/root/.cargo/registry \
    --mount=type=cache,target=/root/.cargo/git \
    cargo fetch

# ── Build the real extension ────────────────────────────────────────────────
# Copy actual source — invalidates only the compile step below.
COPY src/ src/
COPY pg_trickle.control ./

# Compile the extension.
# The target/ cache mount keeps incremental artefacts between builds on the
# same host, so only crates touched by the source change are recompiled.
# Artefacts are copied to /artefacts/ so that Stage 2 can COPY them
# (cache-mounted paths aren't directly visible to downstream COPY --from=).
RUN --mount=type=cache,target=/root/.cargo/registry \
    --mount=type=cache,target=/root/.cargo/git \
    --mount=type=cache,target=/build/target \
    cargo pgrx package --pg-config /usr/bin/pg_config && \
    mkdir -p /artefacts && \
    cp -r target/release/pg_trickle-pg18 /artefacts/

# Verify the artifacts were produced
RUN echo "=== Package artifacts ===" && \
    find /artefacts/pg_trickle-pg18 -type f && \
    echo "========================="

# ── Stage 2: Runtime image with extension installed ─────────────────────────
FROM postgres:18.3

LABEL org.opencontainers.image.title="pg_trickle E2E test image"
LABEL org.opencontainers.image.description="PostgreSQL 18.3 with pg_trickle extension for integration testing"

# Copy extension artifacts from the builder stage
COPY --from=builder \
    /artefacts/pg_trickle-pg18/usr/share/postgresql/18/extension/ \
    /usr/share/postgresql/18/extension/

COPY --from=builder \
    /artefacts/pg_trickle-pg18/usr/lib/postgresql/18/lib/ \
    /usr/lib/postgresql/18/lib/

# Configure shared_preload_libraries so background worker + shared memory work.
# Append to postgresql.conf.sample which is the template for new clusters.
RUN echo "" >> /usr/share/postgresql/postgresql.conf.sample && \
    echo "# pg_trickle E2E test configuration" >> /usr/share/postgresql/postgresql.conf.sample && \
    echo "shared_preload_libraries = 'pg_trickle'" >> /usr/share/postgresql/postgresql.conf.sample && \
    echo "wal_level = logical" >> /usr/share/postgresql/postgresql.conf.sample && \
    echo "max_replication_slots = 10" >> /usr/share/postgresql/postgresql.conf.sample && \
    echo "# Each test database spawns one pg_trickle scheduler BGW via the launcher." >> /usr/share/postgresql/postgresql.conf.sample && \
    echo "# Default max_worker_processes=8 is too tight when many test databases run" >> /usr/share/postgresql/postgresql.conf.sample && \
    echo "# concurrently. The full E2E suite runs ~55 test binaries in parallel, each" >> /usr/share/postgresql/postgresql.conf.sample && \
    echo "# with its own scheduler BGW (e.g. 1 launcher + 55 scheduler workers +  " >> /usr/share/postgresql/postgresql.conf.sample && \
    echo "# autovacuum workers). 32 was too low, causing load_dynamic() failures for" >> /usr/share/postgresql/postgresql.conf.sample && \
    echo "# the shared 'postgres' DB scheduler used by bgworker/cascade tests." >> /usr/share/postgresql/postgresql.conf.sample && \
    echo "max_worker_processes = 128" >> /usr/share/postgresql/postgresql.conf.sample

# Verify the extension files are in place
RUN ls -la /usr/share/postgresql/18/extension/pg_trickle* && \
    ls -la /usr/lib/postgresql/18/lib/pg_trickle*

# Pre-create the extension on the `postgres` database during initdb.
# The launcher background worker probes databases on startup — if the
# extension isn't installed yet it waits 5 min (skip_ttl) before re-probing.
# Creating the extension in initdb.d ensures the launcher's first probe
# finds it and spawns a scheduler immediately.
RUN echo "CREATE EXTENSION IF NOT EXISTS pg_trickle CASCADE;" \
    > /docker-entrypoint-initdb.d/00-create-pg-trickle.sql

EXPOSE 5432