lander/src/main.cpp

#include "crow.h"

extern "C" {
#include "ternarytrie.h"
}

#define ENV(var, env_var)                                                      \
  const char* _##var = getenv(env_var);                                           \
  if (_##var == NULL) {                                                           \
    printf("Missing environment variable %s.\n", env_var);                     \
    return 1;                                                                  \
  } \
  const std::string var = std::string(_##var);

#define AUTH()                                                                 \
  std::string provided_api_key = req.get_header_value("X-Api-Key");            \
  if (api_key.compare(provided_api_key) != 0) {                        \
    return crow::response(crow::status::UNAUTHORIZED);                         \
  }

int main() {
  // Initialize random seed for generating URLs
  srand(time(NULL));

  ENV(api_key, "LANDER_API_KEY");
  ENV(base_url, "LANDER_BASE_URL");

  TernaryTrie *trie = ternarytrie_init();

  std::string file_path = "lander.data";

  std::cout << "Populating trie from file '" << file_path << "'..." << std::endl;

  int count = ternarytrie_populate(trie, file_path.c_str());

  if (count == -1) {
    std::cout << "An error occured while populating the trie." << std::endl;

    exit(1);
  } else {
    std::cout << "Added " << count << " entries to trie." << std::endl;
  }

  crow::SimpleApp app;

  app.loglevel(crow::LogLevel::Warning);

  CROW_ROUTE(app, "/<string>")
      .methods(crow::HTTPMethod::Get)(
          [trie](crow::response &res, std::string s) {
            char *payload = ternarytrie_search(trie, s.c_str());

            if (payload != NULL) {
              res.redirect(payload);
            } else {
              res.code = 404;
            }

            res.end();
          });
  CROW_ROUTE(app, "/").methods(crow::HTTPMethod::Post)(
      [api_key, base_url, trie](const crow::request req) {
        AUTH();

        char *key = ternarytrie_add_random(trie, req.body.c_str());

        if (key == NULL) {
          return crow::response(crow::status::INTERNAL_SERVER_ERROR);
        }

        std::string res = base_url + key;
        free(key);

        return crow::response(res);
      });
  CROW_ROUTE(app, "/<string>")
      .methods(crow::HTTPMethod::Post)(
          [api_key, base_url, trie](const crow::request &req,
                                                  std::string s) {
            AUTH();

            std::string key = req.body;
            bool added = ternarytrie_add(trie, s.c_str(), req.body.c_str());

            if (!added) {
              return crow::response(crow::status::CONFLICT);
            }

            return crow::response(base_url + key);
          });

  app.port(18080).multithreaded().run();
}