Download optimizations (#2786)

* download_model_files metadata writing improvement

* line swap

* reduce line length

* safer download and greater block size

* Minor changes by pycodestyle

---------

Co-authored-by: oobabooga <112222186+oobabooga@users.noreply.github.com>

download-model.py

@@ -77,7 +77,6 @@ class ModelDownloader:
         if os.getenv('HF_USER') is not None and os.getenv('HF_PASS') is not None:
             self.s.auth = (os.getenv('HF_USER'), os.getenv('HF_PASS'))
 
-
     def sanitize_model_and_branch_names(self, model, branch):
         if model[-1] == '/':
             model = model[:-1]
@@ -92,7 +91,6 @@ class ModelDownloader:
 
         return model, branch
 
-
     def get_download_links_from_huggingface(self, model, branch, text_only=False):
         base = "https://huggingface.co"
         page = f"/api/models/{model}/tree/{branch}"
@@ -163,7 +161,6 @@ class ModelDownloader:
 
         return links, sha256, is_lora
 
-
     def get_output_folder(self, model, branch, is_lora, base_folder=None):
         if base_folder is None:
             base_folder = 'models' if not is_lora else 'loras'
@@ -174,10 +171,11 @@ class ModelDownloader:
         output_folder = Path(base_folder) / output_folder
         return output_folder
 
-
     def get_single_file(self, url, output_folder, start_from_scratch=False):
         filename = Path(url.rsplit('/', 1)[1])
         output_path = output_folder / filename
+        headers = {}
+        mode = 'wb'
         if output_path.exists() and not start_from_scratch:
             # Check if the file has already been downloaded completely
             r = self.s.get(url, stream=True, timeout=20)
@@ -187,50 +185,45 @@ class ModelDownloader:
             # Otherwise, resume the download from where it left off
             headers = {'Range': f'bytes={output_path.stat().st_size}-'}
             mode = 'ab'
-        else:
-            headers = {}
-            mode = 'wb'
 
-        r = self.s.get(url, stream=True, headers=headers, timeout=20)
-        with open(output_path, mode) as f:
+        with self.s.get(url, stream=True, headers=headers, timeout=20) as r:
+            r.raise_for_status()  # Do not continue the download if the request was unsuccessful
             total_size = int(r.headers.get('content-length', 0))
-            # Every 4MB we report an update
-            block_size = 4*1024*1024
-
-            with tqdm.tqdm(total=total_size, unit='iB', unit_scale=True, bar_format='{l_bar}{bar}| {n_fmt:6}/{total_fmt:6} {rate_fmt:6}') as t:
-                count = 0
-                for data in r.iter_content(block_size):
-                    t.update(len(data))
-                    f.write(data)
-                    if self.progress_bar is not None:
-                        count += len(data)
-                        self.progress_bar(float(count)/float(total_size), f"Downloading {filename}")
-
+            block_size = 1024 * 1024  # 1MB
+            with open(output_path, mode) as f:
+                with tqdm.tqdm(total=total_size,
+                               unit='iB',
+                               unit_scale=True,
+                               bar_format='{l_bar}{bar}| {n_fmt:6}/{total_fmt:6} {rate_fmt:6}'
+                               ) as t:
+                    count = 0
+                    for data in r.iter_content(block_size):
+                        t.update(len(data))
+                        f.write(data)
+                        if self.progress_bar is not None:
+                            count += len(data)
+                            self.progress_bar(float(count) / float(total_size), f"Downloading {filename}")
 
     def start_download_threads(self, file_list, output_folder, start_from_scratch=False, threads=1):
         thread_map(lambda url: self.get_single_file(url, output_folder, start_from_scratch=start_from_scratch), file_list, max_workers=threads, disable=True)
 
-
-    def download_model_files(self, model, branch, links, sha256, output_folder, progress_bar = None, start_from_scratch=False, threads=1):
+    def download_model_files(self, model, branch, links, sha256, output_folder, progress_bar=None, start_from_scratch=False, threads=1):
         self.progress_bar = progress_bar
         # Creating the folder and writing the metadata
-        if not output_folder.exists():
-            output_folder.mkdir(parents=True, exist_ok=True)
-        with open(output_folder / 'huggingface-metadata.txt', 'w') as f:
-            f.write(f'url: https://huggingface.co/{model}\n')
-            f.write(f'branch: {branch}\n')
-            f.write(f'download date: {str(datetime.datetime.now().strftime("%Y-%m-%d %H:%M:%S"))}\n')
-            sha256_str = ''
-            for i in range(len(sha256)):
-                sha256_str += f'    {sha256[i][1]} {sha256[i][0]}\n'
-            if sha256_str != '':
-                f.write(f'sha256sum:\n{sha256_str}')
+        output_folder.mkdir(parents=True, exist_ok=True)
+        metadata = f'url: https://huggingface.co/{model}\n' \
+                   f'branch: {branch}\n' \
+                   f'download date: {datetime.datetime.now().strftime("%Y-%m-%d %H:%M:%S")}\n'
+        sha256_str = '\n'.join([f'    {item[1]} {item[0]}' for item in sha256])
+        if sha256_str:
+            metadata += f'sha256sum:\n{sha256_str}'
+        metadata += '\n'
+        (output_folder / 'huggingface-metadata.txt').write_text(metadata)
 
         # Downloading the files
         print(f"Downloading the model to {output_folder}")
         self.start_download_threads(links, output_folder, start_from_scratch=start_from_scratch, threads=threads)
 
-
     def check_model_files(self, model, branch, links, sha256, output_folder):
         # Validate the checksums
         validated = True