# Dropshell Build

A Docker-based build system for creating statically-linked C++ executables using Alpine Linux and musl libc.

## Overview

This repository provides a comprehensive C++ development environment with:

1. **dropshell-build-base**: A base image with C++ toolchain and libraries
2. **dropshell-build**: Multi-stage Docker build system for C++ projects  
3. **Test projects**: Sample applications demonstrating the build system

## Features

### Libraries Available

The base image includes statically-linked versions of:

- **Web Framework**: Drogon with async HTTP capabilities
- **Database Support**: PostgreSQL (libpq), MySQL/MariaDB, SQLite3
- **HTTP Clients**: 
  - Custom Drogon-based HTTP utilities (see `ipdemo`)
  - CPR (C++ Requests) library for simplified HTTP requests
- **Networking**: cURL, c-ares, OpenSSL
- **JSON**: nlohmann/json, jsoncpp
- **Compression**: zlib, zstd, lzma
- **Logging**: spdlog, fmt
- **Utilities**: ccache, mold linker

### HTTP Client Options

Two HTTP client approaches are available:

1. **Drogon HTTP Utilities** (see `tests/ipdemo/src/http_utils.hpp`):
   ```cpp
   auto response = http_get("example.com", "/api/endpoint", true, 10.0);
   if (response.success && response.status_code == 200) {
       std::cout << response.body << std::endl;
   }
   ```

2. **CPR Library** (C++ Requests):
   ```cpp
   #include <cpr/cpr.h>
   cpr::Response r = cpr::Get(cpr::Url{"https://example.com/api"});
   if (r.status_code == 200) {
       std::cout << r.text << std::endl;
   }
   ```

   To use CPR in your CMakeLists.txt with proper static linking:

   **Simple approach (recommended for new base images):**
   ```cmake
   find_package(nlohmann_json REQUIRED)
   find_package(CPRStatic REQUIRED)
   
   target_link_libraries(${PROJECT_NAME} PRIVATE 
       nlohmann_json::nlohmann_json 
       cpr::cpr_static)
   ```

   **Backwards-compatible approach (works with all base image versions):**
   ```cmake
   find_package(nlohmann_json REQUIRED)
   
   # Try the new CPRStatic module first, fall back to manual setup
   find_package(CPRStatic QUIET)
   if(NOT CPRStatic_FOUND)
       # Fallback for older base images
       find_library(OPENSSL_SSL_LIB NAMES ssl PATHS /usr/local/lib64 /usr/local/lib NO_DEFAULT_PATH)
       find_library(OPENSSL_CRYPTO_LIB NAMES crypto PATHS /usr/local/lib64 /usr/local/lib NO_DEFAULT_PATH)
       
       add_library(cpr::cpr_static STATIC IMPORTED)
       set_target_properties(cpr::cpr_static PROPERTIES
           IMPORTED_LOCATION "/usr/local/lib/libcpr.a"
           INTERFACE_INCLUDE_DIRECTORIES "/usr/local/include"
           INTERFACE_LINK_LIBRARIES "/usr/local/lib/libcurl.a;${OPENSSL_SSL_LIB};${OPENSSL_CRYPTO_LIB};/usr/lib/libz.a;/usr/lib/libzstd.a;lzma;dl"
       )
   endif()
   
   target_link_libraries(${PROJECT_NAME} PRIVATE 
       nlohmann_json::nlohmann_json 
       cpr::cpr_static)
   ```

## Quick Start

### Building the Base Image

```bash
cd build-base
./build.sh
```

### Building a Project

```bash
./build.sh
```

### Testing

```bash
./test.sh
```

## Project Structure

### Test Projects

- **ipdemo**: Demonstrates Drogon HTTP utilities and JSON processing
- **test_libs**: Tests all available libraries (fmt, spdlog, SQLite3, etc.)
- **cprdemo**: Example using CPR library for HTTP requests

### Environment Variables

- `CMAKE_BUILD_TYPE`: "Debug" or "Release" (default: Debug)
- `PROJECT`: Project name to build (default: ipdemo)

## Installation