Minimal Work Example of building program with LevelDB

building_flow_of_leveldb.sh

# If using macOS, please first install Command-Line Tools, Homebrew, and cmake via the following commands:
# $ xcode-select --install
# $ /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
# $ brew install cmake

# declear vars
WORK_SPACE=$(pwd)
REPO_DIR=${WORK_SPACE}/remote_repo
PROJECT_DIR=${WORK_SPACE}/my_project

LEVELDB_REPO=${REPO_DIR}/leveldb
LEVELDB_BUILD=${LEVELDB_REPO}/build
LEVELDB_INSTALL=${PROJECT_DIR}/local

# clone and build LevelDB
mkdir -p ${REPO_DIR}
git clone --recurse-submodules https://github.com/google/leveldb.git ${LEVELDB_REPO}
mkdir -p ${LEVELDB_BUILD} && cd ${LEVELDB_BUILD}
cmake -DCMAKE_INSTALL_PREFIX=${LEVELDB_INSTALL} -DCMAKE_BUILD_TYPE=Release ${LEVELDB_REPO}
make install -j4

# create several source files for testing

## subdirs
mkdir -p ${PROJECT_DIR}/include/mwe
mkdir -p ${PROJECT_DIR}/src/mwe

## include/mwe/test.h
echo '#ifndef INCLUDE_MWE_TEST_H_
#define INCLUDE_MWE_TEST_H_

void test_leveldb ();

#endif // INCLUDE_MWE_TEST_H_
' | tee ${PROJECT_DIR}/include/mwe/test.h

## src/mwe/test.cc
echo '#include "leveldb/db.h"
#include "mwe/test.h"

void test_leveldb () {
    leveldb::DB* db;
    leveldb::Options options;
    options.create_if_missing = true;
    leveldb::Status status = leveldb::DB::Open(options, "testdb", &db);
    assert(status.ok());
}
' | tee ${PROJECT_DIR}/src/mwe/test.cc

## src/main.cc
echo '#include <iostream>
#include "mwe/test.h"

int main() {
    test_leveldb();
    std::cout << "Build LevelDB Successed." << std::endl;
    return 0;
}
' | tee ${PROJECT_DIR}/src/main.cc

## CMakeLists.txt
echo 'cmake_minimum_required(VERSION 3.9)
project(my_project)

set(CMAKE_CXX_STANDARD 11)
set(CMAKE_CXX_STANDARD_REQUIRED ON)
set(CMAKE_CXX_EXTENSIONS OFF)

include_directories(include local/include)
file(GLOB_RECURSE SOURCES src/*.cc)
add_executable(main ${SOURCES})

find_package(Threads REQUIRED)
find_library (LEVELDB
    NAMES leveldb libleveldb # what to look for
    HINTS ${CMAKE_SOURCE_DIR}/local/lib # where to look
    NO_DEFAULT_PATH) # do not search system default paths

target_link_libraries(main PRIVATE Threads::Threads ${LEVELDB})
' | tee ${PROJECT_DIR}/CMakeLists.txt

# compile and build with LevelDB
cd ${PROJECT_DIR}
mkdir build && cd build
cmake ${PROJECT_DIR} && make -j4

# execute and test
./main