NPRPC Development Docker Image

A development image with NPRPC's C++ library, Swift package and tools pre-built, so a Swift or C++ project can build against NPRPC without building it first. Use it for building; see the multi-stage example below for a small runtime image.

What's Included

Swift 6.3.0 toolchain (the image is based on swift:6.3.0)
NPRPC C++ library (libnprpc.so), headers and CMake config
npidl (IDL compiler) and npnameserver
Swift package nprpc_swift, pre-built: the NPRPC library, and NPRPCWeb for server-rendered pages
swift-mustache, which NPRPCWeb depends on
Boost 1.89.0
CMake, Ninja, pkg-config, Node.js, liburing, and ffmpeg/gpac for media examples

Quick Start

Build the Image

just build-dev-image

This creates nprpc-dev:latest with everything under /opt/:

/opt/nprpc: C++ library, headers, tools, CMake config
/opt/nprpc_swift: Swift package (source + compiled)
/opt/swift-mustache: template engine used by NPRPCWeb
/opt/boost: Boost libraries

The image runs as the ubuntu user (UID/GID 1000). Pass --user $(id -u):$(id -g) so files written to a mounted directory belong to you.

Use in Your Project

1. As Base Image (Dockerfile)

FROM nprpc-dev:latest

WORKDIR /app
COPY Package.swift .
COPY Sources ./Sources

# Swift projects can reference NPRPC package
RUN swift build -c release

2. Mount Project Directory

# Build your Swift project
docker run --rm --user $(id -u):$(id -g) \
  -v $(pwd):/project \
  -w /project \
  nprpc-dev:latest \
  swift build

# Run tests
docker run --rm \
  -v $(pwd):/project \
  -w /project \
  nprpc-dev:latest \
  swift test

3. Interactive Development

docker run -it --rm \
  -v $(pwd):/project \
  -w /project \
  nprpc-dev:latest \
  /bin/bash

# Inside container:
npidl --version          # IDL compiler available
npnameserver &           # Start nameserver
swift build              # Build your project

Using NPRPC in Your Swift Package

Package.swift

// swift-tools-version: 6.0
import PackageDescription

let package = Package(
    name: "MyRpcService",
    dependencies: [
        // Reference installed NPRPC Swift package
        .package(path: "/opt/nprpc_swift")
    ],
    targets: [
        .executableTarget(
            name: "MyRpcService",
            dependencies: [
                .product(name: "NPRPC", package: "nprpc_swift"),
                // Only if you render pages with Mustache templates:
                .product(name: "NPRPCWeb", package: "nprpc_swift"),
            ],
            swiftSettings: [.interoperabilityMode(.Cxx)]
        )
    ]
)

Targets that import NPRPC need C++ interoperability enabled, as above.

Using NPRPC in CMake Projects

The image includes CMake config files for easy integration:

cmake_minimum_required(VERSION 3.15)
project(my_rpc_client)

# Include NPRPC toolchain hints
include(/opt/nprpc-toolchain.cmake)

# Find NPRPC
find_package(nprpc REQUIRED)

add_executable(client client.cpp)
target_link_libraries(client PRIVATE nprpc::nprpc)

Build:

docker run --rm -v $(pwd):/project -w /project nprpc-dev:latest \
  bash -c "cmake -B build && cmake --build build"

Environment Variables

Pre-configured in the image:

BOOST_ROOT=/opt/boost
NPRPC_ROOT=/opt/nprpc
NPRPC_SWIFT_ROOT=/opt/nprpc_swift
PATH includes /opt/nprpc/bin (npidl, npnameserver)
LD_LIBRARY_PATH includes /opt/nprpc/lib and /opt/boost/lib
PKG_CONFIG_PATH includes /opt/nprpc/lib/pkgconfig

Customization

Build with Different Tag

just build-dev-image mycompany/nprpc 1.0.0

Push to Registry

docker tag nprpc-dev:latest myregistry.com/nprpc-dev:latest
docker push myregistry.com/nprpc-dev:latest

Example: Multi-Stage Production Build

# Build stage - use NPRPC dev image
FROM nprpc-dev:latest AS builder

WORKDIR /app
COPY . .
RUN swift build -c release

# Runtime stage - minimal image
FROM swift:6.3.0-slim

# Copy only runtime dependencies
COPY --from=builder /opt/nprpc/lib/libnprpc.so* /usr/local/lib/
COPY --from=builder /opt/boost/lib/libboost_*.so* /usr/local/lib/
COPY --from=builder /app/.build/release/MyApp /usr/local/bin/

RUN ldconfig

CMD ["MyApp"]

Troubleshooting

Swift Can't Find NPRPC Package

Ensure your Package.swift references the correct path:

.package(path: "/opt/nprpc_swift")

CMake Can't Find nprpc

Include the toolchain file:

cmake -DCMAKE_TOOLCHAIN_FILE=/opt/nprpc-toolchain.cmake -B build

Library Not Found at Runtime

Libraries are in LD_LIBRARY_PATH, but if running executables outside the image, copy libs or mount them.

Version Information

Run inside the container:

swift --version        # Swift 6.3.0
npidl --version        # NPRPC IDL compiler
cmake --version        # CMake

docs/DOCKER_DEV_IMAGE.md