Create filetype.py

libs/common/filetype.py

@@ -0,0 +1,98 @@
+# -*- coding: utf-8 -*-
+
+from __future__ import absolute_import
+
+from .match import match
+from .types import TYPES, Type
+
+# Expose supported matchers types
+types = TYPES
+
+
+def guess(obj):
+    """
+    Infers the type of the given input.
+
+    Function is overloaded to accept multiple types in input
+    and perform the needed type inference based on it.
+
+    Args:
+        obj: path to file, bytes or bytearray.
+
+    Returns:
+        The matched type instance. Otherwise None.
+
+    Raises:
+        TypeError: if obj is not a supported type.
+    """
+    return match(obj) if obj else None
+
+
+def guess_mime(obj):
+    """
+    Infers the file type of the given input
+    and returns its MIME type.
+
+    Args:
+        obj: path to file, bytes or bytearray.
+
+    Returns:
+        The matched MIME type as string. Otherwise None.
+
+    Raises:
+        TypeError: if obj is not a supported type.
+    """
+    kind = guess(obj)
+    return kind.mime if kind else kind
+
+
+def guess_extension(obj):
+    """
+    Infers the file type of the given input
+    and returns its RFC file extension.
+
+    Args:
+        obj: path to file, bytes or bytearray.
+
+    Returns:
+        The matched file extension as string. Otherwise None.
+
+    Raises:
+        TypeError: if obj is not a supported type.
+    """
+    kind = guess(obj)
+    return kind.extension if kind else kind
+
+
+def get_type(mime=None, ext=None):
+    """
+    Returns the file type instance searching by
+    MIME type or file extension.
+
+    Args:
+        ext: file extension string. E.g: jpg, png, mp4, mp3
+        mime: MIME string. E.g: image/jpeg, video/mpeg
+
+    Returns:
+        The matched file type instance. Otherwise None.
+    """
+    for kind in types:
+        if kind.extension == ext or kind.mime == mime:
+            return kind
+    return None
+
+
+def add_type(instance):
+    """
+    Adds a new type matcher instance to the supported types.
+
+    Args:
+        instance: Type inherited instance.
+
+    Returns:
+        None
+    """
+    if not isinstance(instance, Type):
+        raise TypeError('instance must inherit from filetype.types.Type')
+
+    types.insert(0, instance)