Files
simple-object-server/src/server.cpp
Your Name 3c5fc11065 filename
2025-05-03 11:15:12 +12:00

362 lines
12 KiB
C++

#include <filesystem>
#include <iostream>
#include <sstream>
#include <fstream>
#include <random> // For random number generation
#include <chrono> // For seeding random number generator
#include <vector> // For getAllKeys
#include <string_view> // For litecask values
#include <sqlite3.h> // Include SQLite
#include <stdexcept> // For std::runtime_error
#include "server.hpp"
#include "hash.hpp"
#include "compress.hpp"
#include "string_utils.hpp" // Include the new utility header
namespace simple_object_storage {
// Simple RAII helper for file deletion
class ScopeFileDeleter {
public:
ScopeFileDeleter(const std::filesystem::path& path) : path_(path), released_(false) {}
~ScopeFileDeleter() {
if (!released_) {
try {
if (std::filesystem::exists(path_)) {
std::filesystem::remove(path_);
}
} catch (const std::filesystem::filesystem_error& e) {
std::cerr << "Error deleting temp file: " << path_ << " - " << e.what() << std::endl;
}
}
}
void release() { released_ = true; }
private:
std::filesystem::path path_;
bool released_;
};
// Helper to execute SQL and check for errors
void execute_sql(sqlite3* db, const char* sql, const std::string& error_msg_prefix) {
char* err_msg = nullptr;
int rc = sqlite3_exec(db, sql, 0, 0, &err_msg);
if (rc != SQLITE_OK) {
std::string error_details = error_msg_prefix + ": " + (err_msg ? err_msg : "Unknown error");
sqlite3_free(err_msg);
throw std::runtime_error(error_details);
}
}
bool Server::init_db() {
try {
std::filesystem::path db_path = config_.object_store_path / "index.db";
db_ = std::make_unique<Database>(db_path);
return true;
} catch (const std::runtime_error& e) {
std::cerr << "Database initialization error: " << e.what() << std::endl;
return false;
}
}
Server::Server(const ServerConfig& config)
: config_(config), running_(false) {
// Ensure object store directory exists
try {
std::filesystem::create_directories(config_.object_store_path);
} catch (const std::filesystem::filesystem_error& e) {
std::cerr << "Failed to create object store directory: " << config_.object_store_path << " - " << e.what() << std::endl;
return;
}
// Initialize the database
if (!init_db()) {
// Error already printed in init_db
// Consider throwing or setting an error state
}
}
Server::~Server() {
stop();
}
bool Server::start() {
if (!db_) { // Check if DB initialization failed
std::cerr << "Database is not initialized. Cannot start server." << std::endl;
return false;
}
setup_routes();
running_ = true;
if (!server_.listen(config_.host.c_str(), config_.port)) {
running_ = false;
std::cerr << "Failed to listen on " << config_.host << ":" << config_.port << std::endl;
return false;
}
return true; // Should not be reached if listen is blocking and successful
}
void Server::stop() {
if (running_) {
server_.stop();
running_ = false;
std::cout << "Server stopped." << std::endl;
}
}
void Server::setup_routes() {
const std::string welcome_page = "<html><body><h1>simple_object_storage Template Registry</h1></body></html>";
// Welcome page
server_.Get("/", [welcome_page](const httplib::Request&, httplib::Response& res) {
res.set_content(welcome_page, "text/html");
});
server_.Get("/index.html", [welcome_page](const httplib::Request&, httplib::Response& res) {
res.set_content(welcome_page, "text/html");
});
// Get object by hash or label:tag
server_.Get("/object/(.*)", [this](const httplib::Request& req, httplib::Response& res) {
handle_get_object(req, res);
});
// Get hash for label:tag
server_.Get("/hash/(.*)", [this](const httplib::Request& req, httplib::Response& res) {
handle_get_hash(req, res);
});
// Get directory listing
server_.Get("/dir", [this](const httplib::Request& req, httplib::Response& res) {
handle_get_directory(req, res);
});
// Upload object
server_.Put("/([^/]+)/(.*)", [this](const httplib::Request& req, httplib::Response& res) {
handle_put_object(req, res);
});
// Get metadata for label:tag
server_.Get("/meta/(.*)", [this](const httplib::Request& req, httplib::Response& res) {
handle_get_metadata(req, res);
});
}
void Server::handle_get_object(const httplib::Request& req, httplib::Response& res) {
const auto& key = req.matches[1].str();
std::string hash_str;
// Check if the key looks like a hash (numeric)
bool is_hash_lookup = true;
for (char c : key) {
if (!std::isdigit(c)) {
is_hash_lookup = false;
break;
}
}
if (!is_hash_lookup) {
// Lookup by label:tag in the database
dbEntry entry;
if (!db_->get(key, entry)) {
res.status = 404;
res.set_content("Object not found (label:tag)", "text/plain");
return;
}
hash_str = entry.hash;
} else {
// Lookup directly by hash
hash_str = key;
}
if (hash_str.empty()) {
res.status = 404;
res.set_content("Object hash could not be determined", "text/plain");
return;
}
// Construct the file path using the hash string
std::filesystem::path file_path = config_.object_store_path / hash_str;
if (!std::filesystem::exists(file_path) || !std::filesystem::is_regular_file(file_path)) {
res.status = 404;
res.set_content("Object file not found for hash: " + hash_str, "text/plain");
return;
}
// Send file using Response::set_file_content
std::string content_type = "application/octet-stream"; // Basic default
res.set_file_content(file_path.string(), content_type);
}
void Server::handle_get_hash(const httplib::Request& req, httplib::Response& res) {
const auto& label_tag = req.matches[1].str();
dbEntry entry;
if (!db_->get(label_tag, entry)) {
res.status = 404;
res.set_content("Label:tag not found", "text/plain");
return;
}
res.set_content(entry.hash, "text/plain");
}
void Server::handle_get_directory(const httplib::Request& /*req*/, httplib::Response& res) {
std::stringstream ss;
std::vector<dbEntry> entries;
if (!db_->list(entries)) {
res.status = 500;
res.set_content("Database error retrieving directory", "text/plain");
return;
}
for (const auto& entry : entries) {
ss << entry.label_tag << "," << entry.hash << "\n";
}
res.set_content(ss.str(), "text/plain");
}
void Server::handle_put_object(const httplib::Request& req, httplib::Response& res) {
const auto& token = req.matches[1].str();
const auto& label_tag = req.matches[2].str();
if (!validate_write_token(token)) {
res.status = 403;
res.set_content("Invalid write token", "text/plain");
return;
}
auto [label, tag] = parse_label_tag(label_tag);
if (label.empty() || tag.empty()) {
res.status = 400;
res.set_content("Invalid label:tag format", "text/plain");
return;
}
// Generate a random number for the temporary filename
std::mt19937_64 rng(std::chrono::high_resolution_clock::now().time_since_epoch().count());
std::uniform_int_distribution<uint64_t> dist;
uint64_t random_num = dist(rng);
std::string temp_filename = "temp_" + std::to_string(random_num);
// Create temporary file
std::filesystem::path temp_path = config_.object_store_path / temp_filename;
std::ofstream temp_file(temp_path, std::ios::binary);
if (!temp_file.is_open()) {
res.status = 500;
res.set_content("Failed to create temporary file", "text/plain");
return;
}
// Write request body to temporary file
temp_file.write(req.body.data(), req.body.size());
temp_file.close();
// Ensure the temporary file is removed even if errors occur
ScopeFileDeleter temp_file_deleter(temp_path);
// Calculate hash
uint64_t hash = hash_file(temp_path.string());
if (hash == 0) {
res.status = 500;
res.set_content("Failed to calculate hash", "text/plain");
return;
}
nlohmann::json metadata;
// Check for filename query parameter
std::string filename = "";
if (req.has_param("filename")) {
filename = req.get_param_value("filename");
metadata["original_filename"] = filename;
}
// Check if filename ends with ".tgz" using the utility function
if (utils::ends_with(filename, ".tgz")) {
metadata["tgz_content_hash"] = get_hash_from_tgz(temp_path.string());
}
add_file_metadata(temp_path.string(), metadata);
// Move file to final location
std::string hash_str = std::to_string(hash);
std::filesystem::path final_path = config_.object_store_path / hash_str;
if (!std::filesystem::exists(final_path)) {
try {
std::filesystem::rename(temp_path, final_path);
temp_file_deleter.release();
} catch (const std::filesystem::filesystem_error& e) {
std::cerr << "Error renaming temp file: " << e.what() << std::endl;
res.status = 500;
res.set_content("Failed to store object file", "text/plain");
return;
}
}
// Update database index
dbEntry entry;
entry.label_tag = label_tag;
entry.hash = hash_str;
entry.metadata = metadata; // Store the potentially updated metadata
if (!db_->update_or_insert(entry)) {
res.status = 500;
res.set_content("Failed to update database index", "text/plain");
// Attempt to clean up the moved file if index fails
try { if (std::filesystem::exists(final_path)) std::filesystem::remove(final_path); } catch(...) {};
return;
}
res.set_content(hash_str, "text/plain");
}
void Server::handle_get_metadata(const httplib::Request& req, httplib::Response& res) {
const auto& label_tag = req.matches[1].str();
dbEntry entry;
if (!db_->get(label_tag, entry)) {
res.status = 404;
res.set_content("Metadata not found for label:tag: " + label_tag, "text/plain");
return;
}
try {
res.set_content(entry.metadata.dump(), "application/json");
} catch (const nlohmann::json::exception& e) {
std::cerr << "Error serializing metadata for " << label_tag << ": " << e.what() << std::endl;
res.status = 500;
res.set_content("Internal server error: Failed to serialize metadata", "text/plain");
}
}
bool Server::validate_write_token(const std::string& token) const {
return std::find(config_.write_tokens.begin(), config_.write_tokens.end(), token) != config_.write_tokens.end();
}
std::pair<std::string, std::string> Server::parse_label_tag(const std::string& label_tag) const {
size_t colon_pos = label_tag.find(':');
if (colon_pos == std::string::npos || colon_pos == 0 || colon_pos == label_tag.length() - 1) {
return {"", ""};
}
return {label_tag.substr(0, colon_pos), label_tag.substr(colon_pos + 1)};
}
void Server::add_file_metadata(const std::string &file_path, nlohmann::json &metadata) const
{
// get the file size
metadata["file_size"] = std::filesystem::file_size(file_path);
// get the file modification time
auto ftime = std::filesystem::last_write_time(file_path);
auto sctp = std::chrono::time_point_cast<std::chrono::system_clock::duration>(
ftime - std::filesystem::file_time_type::clock::now()
+ std::chrono::system_clock::now()
);
metadata["file_modification_time"] = std::chrono::system_clock::to_time_t(sctp);
}
} // namespace simple_object_storage