LocalAI/backend/Dockerfile.audio-cpp

ARG BASE_IMAGE=ubuntu:24.04
ARG APT_MIRROR=""
ARG APT_PORTS_MIRROR=""

# audio-cpp: 0xShug0/audio.cpp, a ggml audio inference framework covering TTS,
# ASR, VAD, diarization, source separation and music generation, wrapped as a
# LocalAI gRPC backend.
#
# BASE_IMAGE is ubuntu:24.04 for cpu and vulkan builds, or
# nvidia/cuda:<ver>-devel-ubuntu24.04 for cublas builds; both ship apt and
# Ubuntu Noble packages, and the CUDA base additionally provides
# /usr/local/cuda. BUILD_TYPE selects the engine backend in the Makefile:
# "" = portable CPU with all ggml CPU variants, "cublas" ->
# -DENGINE_ENABLE_CUDA=ON, "vulkan" -> -DENGINE_ENABLE_VULKAN=ON. Darwin
# (Metal) builds bypass this Dockerfile entirely.
#
# Upstream needs GCC 13 or newer, which ubuntu:24.04 and the CUDA 12/13
# devel-ubuntu24.04 images all provide.
#
# THIS BACKEND CANNOT USE .docker/install-base-deps.sh OR THE PREBUILT
# quay.io/go-skynet/ci-cache:base-grpc-* IMAGES, AND THAT IS NOT A STYLE CHOICE.
#
# Both supply gRPC v1.65 built from source at /opt/grpc, which downstream
# Dockerfiles copy to /usr/local. That gRPC vendors protobuf v26, and protobuf
# has depended on abseil since v22: google/protobuf/message_lite.h includes
# absl/strings/cord.h. audio.cpp links sentencepiece, and our CMakeLists sets
# SPM_PROTOBUF_PROVIDER=package so sentencepiece uses the same protobuf the
# generated backend.pb.cc was built against (the alternative broke every
# nested-message parse; the full account is in backend/cpp/audio-cpp/CMakeLists.txt).
# That makes sentencepiece's init.h include the external message_lite.h while it
# still includes its own vendored mini-abseil from third_party/absl. The vendored
# copy declares `namespace absl { namespace internal { ... } }` and real abseil
# declares `namespace absl { inline namespace lts_20240116 { namespace internal
# { ... } } }`, so every `absl::internal::` reference becomes ambiguous and the
# compile dies in absl/base/casts.h. Verified, not theorised: building this image
# against the base-grpc-amd64 prebuilt fails at
# sentencepiece-static/error.cc.o with "reference to 'internal' is ambiguous".
#
# Ubuntu Noble's apt protobuf is 3.21.12, which predates the abseil dependency,
# so message_lite.h pulls in no abseil and the vendored copy is the only one in
# scope. That is also the exact protobuf/gRPC pair every unit and end-to-end run
# of this backend has been verified against. Keep it: a from-source gRPC here
# does not buy a faster build, it buys a broken one.
#
# The install-base-deps path is additionally unsafe because it drops protoc 27.1
# into /usr/local/bin, which shadows apt's protoc on PATH and would generate
# protobuf-27 sources to be compiled against 3.21 headers.
FROM alpine:3.22 AS ca-certificates

FROM ${BASE_IMAGE} AS builder
COPY --from=ca-certificates /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/ca-certificates.crt
ARG BUILD_TYPE
ARG TARGETARCH
ARG TARGETVARIANT
ARG APT_MIRROR
ARG APT_PORTS_MIRROR
# Selects the CUDA architecture list in backend/cpp/audio-cpp/Makefile. It has
# to be forwarded: upstream compiles engine_runtime for `native` when
# CMAKE_CUDA_ARCHITECTURES is unset, and no CI runner has a GPU to enumerate.
# The value is the same cuda-major-version the matrix entry declares.
ARG CUDA_MAJOR_VERSION

ENV BUILD_TYPE=${BUILD_TYPE} \
    CUDA_MAJOR_VERSION=${CUDA_MAJOR_VERSION} \
    APT_MIRROR=${APT_MIRROR} \
    APT_PORTS_MIRROR=${APT_PORTS_MIRROR} \
    DEBIAN_FRONTEND=noninteractive \
    PATH=/usr/local/cuda/bin:${PATH}

WORKDIR /build

# gRPC/protobuf from apt, deliberately; see the block above. libgrpc++-dev ships
# a CMake config so find_package(gRPC CONFIG) resolves, and libprotobuf-dev
# lands in the layout CMake's FindProtobuf module expects, which matters because
# sentencepiece runs a bare find_package(Protobuf REQUIRED) with no CONFIG
# fallback of its own.
#
# BUILD_TYPE=vulkan additionally needs the loader headers and glslc; both are in
# Noble. The CUDA toolkit for BUILD_TYPE=cublas comes from BASE_IMAGE.
RUN --mount=type=secret,id=build_proxy_ca,target=/run/secrets/build_proxy_ca,mode=0444 --mount=type=bind,source=.docker/install-build-proxy-ca.sh,target=/usr/local/sbin/install-build-proxy-ca --mount=type=bind,source=.docker/apt-mirror.sh,target=/usr/local/sbin/apt-mirror \
    sh /usr/local/sbin/apt-mirror && \
    apt-get update && \
    apt-get install -y --no-install-recommends \
        git cmake build-essential pkg-config ca-certificates \
        libgrpc++-dev libprotobuf-dev protobuf-compiler protobuf-compiler-grpc && \
    if [ "${BUILD_TYPE}" = "vulkan" ]; then \
        apt-get install -y --no-install-recommends libvulkan-dev glslc; \
    fi && \
    if [ "${TARGETARCH}" = "arm64" ]; then \
        apt-get install -y --no-install-recommends gcc-14 g++-14; \
    fi && \
    apt-get clean && \
    rm -rf /var/lib/apt/lists/*

COPY . /LocalAI

# gcc-14 on arm64, for the same reason llama-cpp does it in
# .docker/llama-cpp-compile.sh: ggml's CPU_ALL_VARIANTS table includes armv9.2
# variants built with -march=...+sme, and Noble's default gcc-13 rejects that
# feature modifier outright ("invalid feature modifier 'sme'"). Every variant in
# the table has to COMPILE even though a host only ever dlopens the one its own
# CPU supports, so one unbuildable variant fails the whole image.
#
# ON EVERY arm64 BUILD_TYPE, which is where this differs from llama-cpp's script
# and why that difference is spelled out rather than assumed. llama-cpp only
# needs gcc-14 for its pure-CPU image because its GPU builds run
# llama-cpp-fallback, which has no variant table at all. This backend's Makefile
# sets ENGINE_ENABLE_CPU_ALL_VARIANTS for every non-Darwin build, GPU included,
# so an arm64 GPU image would hit the identical compile error. Gating this on an
# empty BUILD_TYPE would leave that trap armed for the first arm64 GPU entry
# added to the matrix, which today has none.
RUN --mount=type=secret,id=build_proxy_ca,target=/run/secrets/build_proxy_ca,mode=0444 --mount=type=cache,target=/root/.ccache,id=audio-cpp-ccache-${TARGETARCH}-${BUILD_TYPE},sharing=locked \
    if [ "${TARGETARCH}" = "arm64" ]; then \
        export CC=gcc-14 CXX=g++-14; \
    fi && \
    make -C /LocalAI/backend/cpp/audio-cpp BUILD_TYPE=${BUILD_TYPE} \
        CUDA_MAJOR_VERSION=${CUDA_MAJOR_VERSION} NATIVE=false grpc-server package

# The package directory is the whole image: run.sh, grpc-server, the dlopened
# ggml CPU variants, the bundled loader and its library closure, and the
# bundled silero_vad / marblenet_vad assets. Nothing else exists at run time.
FROM scratch
COPY --from=builder /LocalAI/backend/cpp/audio-cpp/package/. ./