2 files changed, 44 insertions, 0 deletions
diff --git a/mdf/util/__init__.py b/mdf/util/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/mdf/util/__init__.py
diff --git a/mdf/util/util.py b/mdf/util/util.py
new file mode 100644
index 0000000..b233d88
--- /dev/null
+++ b/mdf/util/util.py
@@ -0,0 +1,44 @@
+import subprocess
+import urllib.request
+import urllib.error
+
+from time import sleep
+from threading import Lock
+import http.client
+
+
+_print_lock = Lock()
+
+
+def safe_print(*args, **kwargs):
+    with _print_lock:
+        print(*args, **kwargs)
+
+
+def run(args: list, **kwargs):
+    p = subprocess.run(args, **kwargs)
+    if p.returncode != 0:
+        raise OSError(f'convert returned {p.returncode} ('+' '.join(args)+')')
+
+
+def download_file(url, output, handle_http_errors=True) -> bool:
+    tries_left = 3
+    ok = False
+    while tries_left > 0:
+        try:
+            urllib.request.urlretrieve(url, output)
+            ok = True
+            break
+        except http.client.RemoteDisconnected:
+            ok = False
+            print('    caught an exception, sleeping for 2 seconds and retrying...')
+            sleep(2)
+            tries_left -= 1
+        except urllib.error.HTTPError as e:
+            if not handle_http_errors:
+                raise e
+            else:
+                print(f'    failed to download {url}: {str(e)}')
+                return False
+    return ok
+