Merge Pull Request #936 into wechatcom-app

common/utils.py

@@ -0,0 +1,34 @@
+import io
+import os
+
+from PIL import Image
+
+
+def fsize(file):
+    if isinstance(file, io.BytesIO):
+        return file.getbuffer().nbytes
+    elif isinstance(file, str):
+        return os.path.getsize(file)
+    elif hasattr(file, "seek") and hasattr(file, "tell"):
+        pos = file.tell()
+        file.seek(0, os.SEEK_END)
+        size = file.tell()
+        file.seek(pos)
+        return size
+    else:
+        raise TypeError("Unsupported type")
+
+
+def compress_imgfile(file, max_size):
+    if fsize(file) <= max_size:
+        return file
+    file.seek(0)
+    img = Image.open(file)
+    rgb_image = img.convert("RGB")
+    quality = 95
+    while True:
+        out_buf = io.BytesIO()
+        rgb_image.save(out_buf, "JPEG", quality=quality)
+        if fsize(out_buf) <= max_size:
+            return out_buf
+        quality -= 5