common : add callback interface for download progress (#21735)

Signed-off-by: Adrien Gallouët <angt@huggingface.co>

common/arg.cpp

@@ -291,14 +291,16 @@ static bool common_params_handle_remote_preset(common_params & params, llama_exa
         hf_tag = "default";
     }
 
-    const bool offline = params.offline;
     std::string model_endpoint = get_model_endpoint();
     auto preset_url = model_endpoint + hf_repo + "/resolve/main/preset.ini";
 
     // prepare local path for caching
     auto preset_fname = clean_file_name(hf_repo + "_preset.ini");
     auto preset_path = fs_get_cache_file(preset_fname);
-    const int status = common_download_file_single(preset_url, preset_path, params.hf_token, offline);
+    common_download_opts opts;
+    opts.bearer_token = params.hf_token;
+    opts.offline = params.offline;
+    const int status = common_download_file_single(preset_url, preset_path, opts);
     const bool has_preset = status >= 200 && status < 400;
 
     // remote preset is optional, so we don't error out if not found
@@ -341,10 +343,10 @@ static handle_model_result common_params_handle_model(struct common_params_model
             model.hf_file = model.path;
             model.path = "";
         }
-        common_download_model_opts opts;
+        common_download_opts opts;
-        opts.download_mmproj = true;
+        opts.bearer_token = bearer_token;
         opts.offline = offline;
-        auto download_result = common_download_model(model, bearer_token, opts);
+        auto download_result = common_download_model(model, opts, true);
 
         if (download_result.model_path.empty()) {
             LOG_ERR("error: failed to download model from Hugging Face\n");
@@ -365,9 +367,10 @@ static handle_model_result common_params_handle_model(struct common_params_model
             model.path = fs_get_cache_file(string_split<std::string>(f, '/').back());
         }
 
-        common_download_model_opts opts;
+        common_download_opts opts;
+        opts.bearer_token = bearer_token;
         opts.offline = offline;
-        auto download_result = common_download_model(model, bearer_token, opts);
+        auto download_result = common_download_model(model, opts);
         if (download_result.model_path.empty()) {
             LOG_ERR("error: failed to download model from %s\n", model.url.c_str());
             exit(1);

common/download.cpp

@@ -114,7 +114,7 @@ std::pair<std::string, std::string> common_download_split_repo_tag(const std::st
     return {hf_repo, tag};
 }
 
-class ProgressBar {
+class ProgressBar : public common_download_callback {
     static inline std::mutex mutex;
     static inline std::map<const ProgressBar *, int> lines;
     static inline int max_line = 0;
@@ -138,7 +138,11 @@ class ProgressBar {
     }
 
 public:
-    ProgressBar(const std::string & url = "") : filename(url) {
+    ProgressBar() = default;
+
+    void on_start(const common_download_progress & p) override {
+        filename = p.url;
+
         if (auto pos = filename.rfind('/'); pos != std::string::npos) {
             filename = filename.substr(pos + 1);
         }
@@ -156,13 +160,13 @@ public:
         }
     }
 
-    ~ProgressBar() {
+    void on_done(const common_download_progress &, bool) override {
         std::lock_guard<std::mutex> lock(mutex);
         cleanup(this);
     }
 
-    void update(size_t current, size_t total) {
+    void on_update(const common_download_progress & p) override {
-        if (!total || !is_output_a_tty()) {
+        if (!p.total || !is_output_a_tty()) {
             return;
         }
 
@@ -175,8 +179,8 @@ public:
         int lines_up = max_line - lines[this];
 
         size_t bar = (55 - len) * 2;
-        size_t pct = (100 * current) / total;
+        size_t pct = (100 * p.downloaded) / p.total;
-        size_t pos = (bar * current) / total;
+        size_t pos = (bar * p.downloaded) / p.total;
 
         if (lines_up > 0) {
             std::cout << "\033[" << lines_up << "A";
@@ -193,7 +197,7 @@ public:
         }
         std::cout << '\r' << std::flush;
 
-        if (current == total) {
+        if (p.downloaded == p.total) {
             cleanup(this);
         }
     }
@@ -206,8 +210,8 @@ static bool common_pull_file(httplib::Client & cli,
                              const std::string & resolve_path,
                              const std::string & path_tmp,
                              bool supports_ranges,
-                             size_t existing_size,
+                             common_download_progress & p,
-                             size_t & total_size) {
+                             common_download_callback * callback) {
     std::ofstream ofs(path_tmp, std::ios::binary | std::ios::app);
     if (!ofs.is_open()) {
         LOG_ERR("%s: error opening local file for writing: %s\n", __func__, path_tmp.c_str());
@@ -215,29 +219,27 @@ static bool common_pull_file(httplib::Client & cli,
     }
 
     httplib::Headers headers;
-    if (supports_ranges && existing_size > 0) {
+    if (supports_ranges && p.downloaded > 0) {
-        headers.emplace("Range", "bytes=" + std::to_string(existing_size) + "-");
+        headers.emplace("Range", "bytes=" + std::to_string(p.downloaded) + "-");
     }
 
     const char * func = __func__; // avoid __func__ inside a lambda
-    size_t downloaded = existing_size;
     size_t progress_step = 0;
-    ProgressBar bar(resolve_path);
 
     auto res = cli.Get(resolve_path, headers,
         [&](const httplib::Response &response) {
-            if (existing_size > 0 && response.status != 206) {
+            if (p.downloaded > 0 && response.status != 206) {
                 LOG_WRN("%s: server did not respond with 206 Partial Content for a resume request. Status: %d\n", func, response.status);
                 return false;
             }
-            if (existing_size == 0 && response.status != 200) {
+            if (p.downloaded == 0 && response.status != 200) {
                 LOG_WRN("%s: download received non-successful status code: %d\n", func, response.status);
                 return false;
             }
-            if (total_size == 0 && response.has_header("Content-Length")) {
+            if (p.total == 0 && response.has_header("Content-Length")) {
                 try {
                     size_t content_length = std::stoull(response.get_header_value("Content-Length"));
-                    total_size = existing_size + content_length;
+                    p.total = p.downloaded + content_length;
                 } catch (const std::exception &e) {
                     LOG_WRN("%s: invalid Content-Length header: %s\n", func, e.what());
                 }
@@ -250,11 +252,13 @@ static bool common_pull_file(httplib::Client & cli,
                 LOG_ERR("%s: error writing to file: %s\n", func, path_tmp.c_str());
                 return false;
             }
-            downloaded += len;
+            p.downloaded += len;
             progress_step += len;
 
-            if (progress_step >= total_size / 1000 || downloaded == total_size) {
+            if (progress_step >= p.total / 1000 || p.downloaded == p.total) {
-                bar.update(downloaded, total_size);
+                if (callback) {
+                    callback->on_update(p);
+                }
                 progress_step = 0;
             }
             return true;
@@ -275,11 +279,10 @@ static bool common_pull_file(httplib::Client & cli,
 
 // download one single file from remote URL to local path
 // returns status code or -1 on error
-static int common_download_file_single_online(const std::string        & url,
+static int common_download_file_single_online(const std::string & url,
-                                              const std::string        & path,
+                                              const std::string & path,
-                                              const std::string        & bearer_token,
+                                              const common_download_opts & opts,
-                                              const common_header_list & custom_headers,
+                                              bool skip_etag) {
-                                              bool                       skip_etag = false) {
     static const int max_attempts        = 3;
     static const int retry_delay_seconds = 2;
 
@@ -293,14 +296,14 @@ static int common_download_file_single_online(const std::string        & url,
     auto [cli, parts] = common_http_client(url);
 
     httplib::Headers headers;
-    for (const auto & h : custom_headers) {
+    for (const auto & h : opts.headers) {
         headers.emplace(h.first, h.second);
     }
     if (headers.find("User-Agent") == headers.end()) {
         headers.emplace("User-Agent", "llama-cpp/" + build_info);
     }
-    if (!bearer_token.empty()) {
+    if (!opts.bearer_token.empty()) {
-        headers.emplace("Authorization", "Bearer " + bearer_token);
+        headers.emplace("Authorization", "Bearer " + opts.bearer_token);
     }
     cli.set_default_headers(headers);
 
@@ -326,10 +329,11 @@ static int common_download_file_single_online(const std::string        & url,
         etag = head->get_header_value("ETag");
     }
 
-    size_t total_size = 0;
+    common_download_progress p;
+    p.url = url;
     if (head->has_header("Content-Length")) {
         try {
-            total_size = std::stoull(head->get_header_value("Content-Length"));
+            p.total = std::stoull(head->get_header_value("Content-Length"));
         } catch (const std::exception& e) {
             LOG_WRN("%s: invalid Content-Length in HEAD response: %s\n", __func__, e.what());
         }
@@ -357,13 +361,17 @@ static int common_download_file_single_online(const std::string        & url,
 
     { // silent
         std::error_code ec;
-        std::filesystem::path p(path);
+        std::filesystem::create_directories(std::filesystem::path(path).parent_path(), ec);
-        std::filesystem::create_directories(p.parent_path(), ec);
     }
 
+    bool success = false;
     const std::string path_temporary = path + ".downloadInProgress";
     int delay = retry_delay_seconds;
 
+    if (opts.callback) {
+        opts.callback->on_start(p);
+    }
+
     for (int i = 0; i < max_attempts; ++i) {
         if (i) {
             LOG_WRN("%s: retrying after %d seconds...\n", __func__, delay);
@@ -378,28 +386,38 @@ static int common_download_file_single_online(const std::string        & url,
                 existing_size = std::filesystem::file_size(path_temporary);
             } else if (remove(path_temporary.c_str()) != 0) {
                 LOG_ERR("%s: unable to delete file: %s\n", __func__, path_temporary.c_str());
-                return -1;
+                break;
             }
         }
 
+        p.downloaded = existing_size;
+
         LOG_DBG("%s: downloading from %s to %s (etag:%s)...\n",
                 __func__, common_http_show_masked_url(parts).c_str(),
                 path_temporary.c_str(), etag.c_str());
 
-        if (common_pull_file(cli, parts.path, path_temporary, supports_ranges, existing_size, total_size)) {
+        if (common_pull_file(cli, parts.path, path_temporary, supports_ranges, p, opts.callback)) {
             if (std::rename(path_temporary.c_str(), path.c_str()) != 0) {
                 LOG_ERR("%s: unable to rename file: %s to %s\n", __func__, path_temporary.c_str(), path.c_str());
-                return -1;
+                break;
             }
             if (!etag.empty() && !skip_etag) {
                 write_etag(path, etag);
             }
-            return head->status;
+            success = true;
+            break;
         }
     }
 
-    LOG_ERR("%s: download failed after %d attempts\n", __func__, max_attempts);
+    if (opts.callback) {
-    return -1; // max attempts reached
+        opts.callback->on_done(p, success);
+    }
+    if (!success) {
+        LOG_ERR("%s: download failed after %d attempts\n", __func__, max_attempts);
+        return -1; // max attempts reached
+    }
+
+    return head->status;
 }
 
 std::pair<long, std::vector<char>> common_remote_get_content(const std::string          & url,
@@ -438,12 +456,15 @@ std::pair<long, std::vector<char>> common_remote_get_content(const std::string
 
 int common_download_file_single(const std::string & url,
                                 const std::string & path,
-                                const std::string & bearer_token,
+                                const common_download_opts & opts,
-                                bool offline,
-                                const common_header_list & headers,
                                 bool skip_etag) {
-    if (!offline) {
+    if (!opts.offline) {
-        return common_download_file_single_online(url, path, bearer_token, headers, skip_etag);
+        ProgressBar tty_cb;
+        common_download_opts online_opts = opts;
+        if (!online_opts.callback) {
+            online_opts.callback = &tty_cb;
+        }
+        return common_download_file_single_online(url, path, online_opts, skip_etag);
     }
 
     if (!std::filesystem::exists(path)) {
@@ -452,6 +473,16 @@ int common_download_file_single(const std::string & url,
     }
 
     LOG_DBG("%s: using cached file (offline mode): %s\n", __func__, path.c_str());
+
+    // notify the callback that the file was cached
+    if (opts.callback) {
+        common_download_progress p;
+        p.url = url;
+        p.cached = true;
+        opts.callback->on_start(p);
+        opts.callback->on_done(p, true);
+    }
+
     return 304; // Not Modified - fake cached response
 }
 
@@ -631,16 +662,16 @@ struct hf_plan {
     hf_cache::hf_file mmproj;
 };
 
-static hf_plan get_hf_plan(const common_params_model        & model,
+static hf_plan get_hf_plan(const common_params_model  & model,
-                           const std::string                & token,
+                           const common_download_opts & opts,
-                           const common_download_model_opts & opts) {
+                           bool download_mmproj) {
     hf_plan plan;
     hf_cache::hf_files all;
 
     auto [repo, tag] = common_download_split_repo_tag(model.hf_repo);
 
     if (!opts.offline) {
-        all = hf_cache::get_repo_files(repo, token);
+        all = hf_cache::get_repo_files(repo, opts.bearer_token);
     }
     if (all.empty()) {
         all = hf_cache::get_cached_files(repo);
@@ -675,7 +706,7 @@ static hf_plan get_hf_plan(const common_params_model        & model,
     plan.primary = primary;
     plan.model_files = get_split_files(all, primary);
 
-    if (opts.download_mmproj) {
+    if (download_mmproj) {
         plan.mmproj = find_best_mmproj(all, primary.path);
     }
 
@@ -710,10 +741,9 @@ static std::vector<download_task> get_url_tasks(const common_params_model & mode
     return tasks;
 }
 
-common_download_model_result common_download_model(const common_params_model        & model,
+common_download_model_result common_download_model(const common_params_model  & model,
-                                                   const std::string                & bearer_token,
+                                                   const common_download_opts & opts,
-                                                   const common_download_model_opts & opts,
+                                                   bool download_mmproj) {
-                                                   const common_header_list         & headers) {
     common_download_model_result result;
     std::vector<download_task> tasks;
     hf_plan hf;
@@ -721,7 +751,7 @@ common_download_model_result common_download_model(const common_params_model
     bool is_hf = !model.hf_repo.empty();
 
     if (is_hf) {
-        hf = get_hf_plan(model, bearer_token, opts);
+        hf = get_hf_plan(model, opts, download_mmproj);
         for (const auto & f : hf.model_files) {
             tasks.push_back({f.url, f.local_path});
         }
@@ -742,8 +772,8 @@ common_download_model_result common_download_model(const common_params_model
     std::vector<std::future<bool>> futures;
     for (const auto & task : tasks) {
         futures.push_back(std::async(std::launch::async,
-            [&task, &bearer_token, offline = opts.offline, &headers, is_hf]() {
+            [&task, &opts, is_hf]() {
-                int status = common_download_file_single(task.url, task.path, bearer_token, offline, headers, is_hf);
+                int status = common_download_file_single(task.url, task.path, opts, is_hf);
                 return is_http_status_ok(status);
             }
         ));
@@ -879,7 +909,9 @@ std::string common_docker_resolve_model(const std::string & docker) {
         std::string local_path = fs_get_cache_file(model_filename);
 
         const std::string blob_url = url_prefix + "/blobs/" + gguf_digest;
-        const int http_status = common_download_file_single(blob_url, local_path, token, false, {});
+        common_download_opts opts;
+        opts.bearer_token = token;
+        const int http_status = common_download_file_single(blob_url, local_path, opts);
         if (!is_http_status_ok(http_status)) {
             throw std::runtime_error("Failed to download Docker Model");
         }

common/download.h

@@ -8,6 +8,21 @@ struct common_params_model;
 using common_header      = std::pair<std::string, std::string>;
 using common_header_list = std::vector<common_header>;
 
+struct common_download_progress {
+    std::string url;
+    size_t downloaded = 0;
+    size_t total      = 0;
+    bool cached       = false;
+};
+
+class common_download_callback {
+public:
+    virtual ~common_download_callback() = default;
+    virtual void on_start(const common_download_progress & p) = 0;
+    virtual void on_update(const common_download_progress & p) = 0;
+    virtual void on_done(const common_download_progress & p, bool ok) = 0;
+};
+
 struct common_remote_params {
     common_header_list headers;
     long timeout  = 0;           // in seconds, 0 means no timeout
@@ -31,10 +46,12 @@ struct common_cached_model_info {
     }
 };
 
-// Options for common_download_model
+// Options for common_download_model and common_download_file_single
-struct common_download_model_opts {
+struct common_download_opts {
-    bool download_mmproj = false;
+    std::string bearer_token;
-    bool offline         = false;
+    common_header_list headers;
+    bool offline = false;
+    common_download_callback * callback = nullptr;
 };
 
 // Result of common_download_model
@@ -69,9 +86,8 @@ struct common_download_model_result {
 // returns result with model_path and mmproj_path (empty on failure)
 common_download_model_result common_download_model(
     const common_params_model & model,
-    const std::string & bearer_token,
+    const common_download_opts & opts = {},
-    const common_download_model_opts & opts = {},
+    bool download_mmproj = false
-    const common_header_list & headers = {}
 );
 
 // returns list of cached models
@@ -82,9 +98,7 @@ std::vector<common_cached_model_info> common_list_cached_models();
 // skip_etag: if true, don't read/write .etag files (for HF cache where filename is the hash)
 int common_download_file_single(const std::string & url,
                                 const std::string & path,
-                                const std::string & bearer_token,
+                                const common_download_opts & opts = {},
-                                bool offline,
-                                const common_header_list & headers = {},
                                 bool skip_etag = false);
 
 // resolve and download model from Docker registry

tools/llama-bench/llama-bench.cpp

@@ -1014,7 +1014,9 @@ static cmd_params parse_cmd_params(int argc, char ** argv) {
                 model.hf_file = params.hf_file[i];
             }
 
-            auto download_result = common_download_model(model, params.hf_token);
+            common_download_opts opts;
+            opts.bearer_token = params.hf_token;
+            auto download_result = common_download_model(model, opts);
             if (download_result.model_path.empty()) {
                 fprintf(stderr, "error: failed to download model from HuggingFace\n");
                 exit(1);