rocks_example.cc

// osx instructions on Mojave (as of 2020-12-27)
// brew install llvm
// brew insall rocksdb
// llvm-g++ -std=c++14 -L /usr/local/Cellar/rocksdb/6.14.6_1/lib -lrocksdb rocks_example.cc
#include "rocksdb/db.h"
#include <iostream>
#include <cassert>
#include <sstream>

void assert_status(rocksdb::Status status, std::string msg ) {
  if (!status.ok()) {
    std::cout << msg << ". Exiting with failure. status -> " << status.ToString() << std::endl;
    assert(false);
  }
}

rocksdb::Status log_failure(rocksdb::Status status, std::string msg ) {
  if (!status.ok()) {
    std::cout << msg << ". Status -> " << status.ToString() << std::endl;
  }
  return status;
}


std::unique_ptr<rocksdb::DB> get_db(std::string dbfile) {
  rocksdb::Options options;
  options.create_if_missing = true;
  rocksdb::DB* db_raw_ptr;
  rocksdb::Status status =
    rocksdb::DB::Open(options, dbfile, &db_raw_ptr);
  std::unique_ptr<rocksdb::DB> db(db_raw_ptr);
  assert_status(status, "Failed to create db");
  return db;
}

int main() {
  std::unique_ptr<rocksdb::DB> db = get_db("/tmp/testdb");
  assert_status(
    db->Put(rocksdb::WriteOptions(), "k1", "v1"),
    "Failed to write k1 = v1"
  );
  std::string val;
  assert_status(
    db->Get(rocksdb::ReadOptions(), "k1", &val),
    "Failed to read k1"
  );
  std::cout << "Value for k1 is " << val << std::endl;
  log_failure(
    db->Get(rocksdb::ReadOptions(), "k2", &val),
    "Failed to read k2"
  );
  return 0;
}