Rename http downloader module

PFERD/downloaders.py

@@ -0,0 +1,51 @@
+"""
+General downloaders useful in many situations
+"""
+
+from pathlib import Path
+from typing import Any, Dict, Optional
+
+import requests
+import requests.auth
+
+from .organizer import Organizer
+from .tmp_dir import TmpDir
+from .utils import stream_to_path
+
+
+class HttpDownloader():
+    """A HTTP downloader that can handle HTTP basic auth."""
+
+    def __init__(
+            self,
+            tmp_dir: TmpDir,
+            organizer: Organizer,
+            username: Optional[str],
+            password: Optional[str],
+    ):
+        """Create a new http downloader."""
+        self._organizer = organizer
+        self._tmp_dir = tmp_dir
+        self._username = username
+        self._password = password
+        self._session = self._build_session()
+
+    def _build_session(self) -> requests.Session:
+        session = requests.Session()
+        if self._username and self._password:
+            session.auth = requests.auth.HTTPBasicAuth(
+                self._username, self._password
+            )
+        return session
+
+    def download(self, url: str, target_path: Path, parameters: Dict[str, Any] = {}) -> None:
+        """Download a given url to a given path, optionally with some get parameters."""
+        with self._session.get(url, params=parameters) as response:
+            if response.status_code == 200:
+                tmp_file = self._tmp_dir.new_file()
+                stream_to_path(response, tmp_file)
+                self._organizer.accept_file(tmp_file, target_path)
+            else:
+                raise Exception(
+                    f"Could not download file, got response {response.status_code}"
+                )