diff --git a/modules/http/server/middlewares/file_downloader_middleware.cpp b/modules/http/server/middlewares/file_downloader_middleware.cpp index 2ca245b7428df0e0f27f937e0eac7a767ef10783..6c326e05b6148fcede5659afb290c58d97f23687 100644 --- a/modules/http/server/middlewares/file_downloader_middleware.cpp +++ b/modules/http/server/middlewares/file_downloader_middleware.cpp @@ -22,12 +22,16 @@ #include #include #include +#include +#include #include #include #include #include +#include #include +#include #include namespace tbox { @@ -35,7 +39,9 @@ namespace http { namespace server { namespace { -bool IsPathSafe(const std::string& path) { + +bool IsPathSafe(const std::string& path) +{ //! 检查是否有".."路径组件，这可能导致目录遍历 std::istringstream path_stream(path); std::string component; @@ -47,6 +53,79 @@ bool IsPathSafe(const std::string& path) { return true; } + +std::string GenerateETag(time_t mtime, off_t size) +{ + return "\"" + std::to_string(static_cast(mtime)) + + "-" + std::to_string(static_cast(size)) + "\""; +} + +std::string HttpDateToString(time_t t) +{ + struct tm tm_buf; + gmtime_r(&t, &tm_buf); + char buf[64]; + strftime(buf, sizeof(buf), "%a, %d %b %Y %H:%M:%S GMT", &tm_buf); + return buf; +} + +time_t StringToHttpDate(const std::string& s) +{ + struct tm t = {}; + if (strptime(s.c_str(), "%a, %d %b %Y %H:%M:%S GMT", &t) == nullptr) + return -1; + return timegm(&t); +} + +std::string GetHeader(const tbox::http::Headers& headers, const std::string& lower_name) +{ + for (const auto& h : headers) { + if (tbox::util::string::ToLower(h.first) == lower_name) + return h.second; + } + return ""; +} + +//! 解析 +bool ParseRangeString(const std::string &range_str, size_t file_size, size_t &range_begin, size_t &range_end) +{ + std::string range_val = range_str.substr(6); + auto dash_pos = range_val.find('-'); + if (dash_pos == std::string::npos) + return false; + + //!FIXME: 暂不支持 1000-1999, 3000-3555, 多段返回的情况 + auto comma_pos = range_val.find(',', dash_pos); + if (comma_pos != std::string::npos) { + return false; + } + + std::string begin_str = range_val.substr(0, dash_pos); + std::string end_str = range_val.substr(dash_pos + 1); + + if (begin_str.empty()) { //! 出现：-500 + size_t suffix_size = 0; + if (!util::StringTo(end_str, suffix_size)) + return false; + + range_begin = (suffix_size >= file_size) ? 0 : file_size - suffix_size; + range_end = file_size - 1; + + } else { //! 出现：1000-1999 或 1000- + if (!util::StringTo(begin_str, range_begin)) + return false; + + if (!end_str.empty()) { + if (!util::StringTo(end_str, range_end)) + return false; + } else { + range_end = file_size - 1; + } + } + + return true; +} + } //! 目录配置项 @@ -58,8 +137,8 @@ struct DirectoryConfig { //! 中间件私有数据结构 struct FileDownloaderMiddleware::Data { - eventx::ThreadExecutor *worker = nullptr; - eventx::WorkThread *inner_worker = nullptr; + eventx::ThreadExecutor *worker = nullptr; + eventx::WorkThread *inner_worker = nullptr; std::vector directories; //! 目录配置列表 std::map path_mappings;//! 特定路径映射 std::map mime_types; //! MIME类型映射 @@ -74,10 +153,9 @@ struct FileDownloaderMiddleware::Data { , switch_to_worker_filesize_threshold(100 << 10) { if (worker == nullptr) { - inner_worker = new tbox::eventx::WorkThread(wp_loop); + inner_worker = new eventx::WorkThread(wp_loop); worker = inner_worker; } - //! 初始化常见MIME类型 mime_types["html"] = "text/html"; mime_types["htm"] = "text/html"; @@ -104,13 +182,15 @@ struct FileDownloaderMiddleware::Data { mime_types["ttf"] = "font/ttf"; mime_types["otf"] = "font/otf"; } - ~Data() { + + ~Data() + { CHECK_DELETE_RESET_OBJ(inner_worker); } }; FileDownloaderMiddleware::FileDownloaderMiddleware(event::Loop *wp_loop, eventx::ThreadExecutor *wp_thread_executor) - : d_(new Data(wp_loop, wp_thread_executor)) + : d_(new Data(wp_loop, wp_thread_executor)) { } FileDownloaderMiddleware::~FileDownloaderMiddleware() @@ -118,7 +198,8 @@ FileDownloaderMiddleware::~FileDownloaderMiddleware() bool FileDownloaderMiddleware::addDirectory(const std::string& url_prefix, const std::string& local_path, - const std::string& default_file) { + const std::string& default_file) +{ //! 验证URL前缀是否以'/'开头 if (url_prefix.empty() || url_prefix[0] != '/') { LogErr("Invalid URL prefix: %s. Must start with '/'", url_prefix.c_str()); @@ -146,25 +227,42 @@ bool FileDownloaderMiddleware::addDirectory(const std::string& url_prefix, return true; } -void FileDownloaderMiddleware::setDirectoryListingEnabled(bool enable) { +void FileDownloaderMiddleware::setDirectoryListingEnabled(bool enable) +{ d_->directory_listing_enabled = enable; } -void FileDownloaderMiddleware::setPathMapping(const std::string& url, const std::string& file) { +void FileDownloaderMiddleware::setPathMapping(const std::string& url, const std::string& file) +{ d_->path_mappings[url] = file; } -void FileDownloaderMiddleware::setDefaultMimeType(const std::string& mime_type) { +void FileDownloaderMiddleware::setDefaultMimeType(const std::string& mime_type) +{ d_->default_mime_type = mime_type; } -void FileDownloaderMiddleware::setMimeType(const std::string& ext, const std::string& mime_type) { +void FileDownloaderMiddleware::setMimeType(const std::string& ext, const std::string& mime_type) +{ d_->mime_types[ext] = mime_type; } -void FileDownloaderMiddleware::handle(ContextSptr sp_ctx, const NextFunc& next) { +void FileDownloaderMiddleware::handle(ContextSptr sp_ctx, const NextFunc& next) +{ const auto& request = sp_ctx->req(); + //! 处理 OPTIONS 预检请求（浏览器跨域访问） + if (request.method == Method::kOptions) { + auto& res = sp_ctx->res(); + res.status_code = StatusCode::k200_OK; + res.headers["Access-Control-Allow-Origin"] = "*"; + res.headers["Access-Control-Allow-Methods"] = "GET, HEAD, OPTIONS"; + res.headers["Access-Control-Allow-Headers"] = "Auth, Range, If-Range, If-None-Match, If-Modified-Since"; + res.headers["Access-Control-Allow-Private-Network"] = "true"; + res.headers["Access-Control-Max-Age"] = "86400"; + return; + } + //! 只处理GET和HEAD请求 if (request.method != Method::kGet && request.method != Method::kHead) { next(); @@ -241,7 +339,8 @@ void FileDownloaderMiddleware::handle(ContextSptr sp_ctx, const NextFunc& next) next(); } -std::string FileDownloaderMiddleware::getMimeType(const std::string& filename) const { +std::string FileDownloaderMiddleware::getMimeType(const std::string& filename) const +{ //! 查找最后一个点的位置 size_t dot_pos = filename.find_last_of('.'); if (dot_pos != std::string::npos) { @@ -256,53 +355,124 @@ std::string FileDownloaderMiddleware::getMimeType(const std::string& filename) c return d_->default_mime_type; } -bool FileDownloaderMiddleware::respondFile(ContextSptr sp_ctx, const std::string& file_path) { +bool FileDownloaderMiddleware::respondFile(ContextSptr sp_ctx, const std::string& file_path) +{ auto& res = sp_ctx->res(); - //! 打开文件 - std::ifstream file(file_path, std::ios::binary | std::ios::ate); - if (!file.is_open()) { + //! 用 stat() 获取文件元信息，同时验证文件是否存在 + struct stat file_stat; + if (::stat(file_path.c_str(), &file_stat) != 0) { res.status_code = StatusCode::k404_NotFound; return true; } - res.headers["Content-Type"] = getMimeType(file_path); + size_t file_size = static_cast(file_stat.st_size); + time_t file_mtime = file_stat.st_mtime; + std::string etag = GenerateETag(file_mtime, file_stat.st_size); + std::string last_modified = HttpDateToString(file_mtime); + + res.headers["Content-Type"] = getMimeType(file_path); + res.headers["Accept-Ranges"] = "bytes"; + res.headers["ETag"] = etag; + res.headers["Last-Modified"] = last_modified; + res.headers["Cache-Control"] = "public, max-age=0, must-revalidate"; + res.headers["Access-Control-Allow-Origin"] = "*"; + res.headers["Access-Control-Expose-Headers"] = "Content-Range, Content-Length, ETag, Last-Modified"; + + //! 条件请求：If-None-Match 优先于 If-Modified-Since（RFC 7232 §6） + std::string if_none_match = GetHeader(sp_ctx->req().headers, "if-none-match"); + if (!if_none_match.empty()) { + if (if_none_match == etag) { + res.status_code = StatusCode::k304_NotModified; + return true; + } + } else { + std::string if_modified_since = GetHeader(sp_ctx->req().headers, "if-modified-since"); + if (!if_modified_since.empty()) { + time_t since = StringToHttpDate(if_modified_since); + if (since != -1 && file_mtime <= since) { + res.status_code = StatusCode::k304_NotModified; + return true; + } + } + } - //! 获取文件大小 - size_t file_size = static_cast(file.tellg()); - file.seekg(0, std::ios::beg); + //! 解析 Range 请求头（需在 HEAD 判断之前，确保非法 Range 返回 416） + size_t range_begin = 0; + size_t range_end = file_size > 0 ? file_size - 1 : 0; + bool has_range = false; - //! 如果是HEAD请求，不返回内容 - if (sp_ctx->req().method == Method::kHead) { - res.status_code = StatusCode::k200_OK; - res.headers["Content-Length"] = std::to_string(file_size); - return true; + if (file_size > 0) { + auto range_str = GetHeader(sp_ctx->req().headers, "range"); + if (util::string::IsStartWith(range_str, "bytes=")) { + has_range = ParseRangeString(range_str, file_size, range_begin, range_end); + } + + //! If-Range：ETag 不匹配时降级为全量响应，保证数据一致性 + if (has_range) { + std::string if_range = GetHeader(sp_ctx->req().headers, "if-range"); + if (!if_range.empty() && if_range != etag) { + has_range = false; + range_begin = 0; + range_end = file_size - 1; + } + } + + //! 校验范围合法性 + if (has_range && (range_begin >= file_size || range_end >= file_size || range_begin > range_end)) { + res.status_code = StatusCode::k416_RequestedRangeNotSatisfiable; + res.headers["Content-Range"] = "bytes */" + std::to_string(file_size); + return true; + } } - //! 文件是否大于100KB - if (file_size < d_->switch_to_worker_filesize_threshold) { - //! 小文件就直接读了 + size_t content_length = file_size > 0 ? range_end - range_begin + 1 : 0; + res.headers["Content-Length"] = std::to_string(content_length); + + if (has_range) { + res.status_code = StatusCode::k206_PartialContent; + res.headers["Content-Range"] = "bytes " + std::to_string(range_begin) + "-" + + std::to_string(range_end) + "/" + std::to_string(file_size); + } else { res.status_code = StatusCode::k200_OK; - res.headers["Content-Length"] = std::to_string(file_size); - //! 将文件内容读到body中去 - res.body = std::string((std::istreambuf_iterator(file)), std::istreambuf_iterator()); - LogInfo("Served file: %s (%zu bytes)", file_path.c_str(), file_size); + } + + //! HEAD 请求不返回 body + if (sp_ctx->req().method == Method::kHead) + return true; + //! 空文件直接返回 + if (file_size == 0) + return true; + + if (content_length < d_->switch_to_worker_filesize_threshold) { + std::ifstream file(file_path, std::ios::binary); + if (!file.is_open()) { + res.status_code = StatusCode::k500_InternalServerError; + return true; + } + file.seekg(static_cast(range_begin)); + res.body.resize(content_length); + file.read(&res.body[0], static_cast(content_length)); + LogInfo("Served file: %s (bytes %zu-%zu/%zu)", + file_path.c_str(), range_begin, range_end, file_size); } else { - //! 文件太大就采用子线程去读 d_->worker->execute( - [sp_ctx, file_path] { + [sp_ctx, file_path, range_begin, content_length] { auto& res = sp_ctx->res(); - if (util::fs::ReadBinaryFromFile(file_path, res.body)) { - res.status_code = StatusCode::k200_OK; - res.headers["Content-Length"] = std::to_string(res.body.size()); - LogInfo("Served file: %s (%zu bytes)", file_path.c_str(), res.body.size()); + std::ifstream f(file_path, std::ios::binary); + if (f.is_open()) { + f.seekg(static_cast(range_begin)); + res.body.resize(content_length); + f.read(&res.body[0], static_cast(content_length)); + LogInfo("Served file(worker): %s (%zu bytes from %zu)", + file_path.c_str(), content_length, range_begin); } else { - res.status_code = StatusCode::k404_NotFound; + res.status_code = StatusCode::k500_InternalServerError; } }, - [sp_ctx] { } //! 这是为了确保sp_ctx在主线程上析构 - ); + [sp_ctx] { } //! 确保 sp_ctx 在主线程上析构 + ); } return true; @@ -310,7 +480,8 @@ bool FileDownloaderMiddleware::respondFile(ContextSptr sp_ctx, const std::string bool FileDownloaderMiddleware::respondDirectory(ContextSptr sp_ctx, const std::string& dir_path, - const std::string& url_path) { + const std::string& url_path) +{ try { //! 生成HTML目录列表 std::ostringstream html_oss;