Added a slightly changed version from the awscli find bucket function (…

…#648)

* Added a slightly changed version from the awscli find bucket function

* lint

Co-authored-by: Martin Durant <martin.durant@alumni.utoronto.ca>

s3fs/core.py

@@ -7,6 +7,7 @@
 import socket
 from typing import Tuple, Optional
 import weakref
+import re
 
 from urllib3.exceptions import IncompleteRead
 
@@ -363,6 +364,34 @@ def _get_kwargs_from_urls(urlpath):
                 out["version_aware"] = True
         return out
 
+    def _find_bucket_key(self, s3_path):
+        """
+        This is a helper function that given an s3 path such that the path is of
+        the form: bucket/key
+        It will return the bucket and the key represented by the s3 path
+        """
+
+        _S3_ACCESSPOINT_TO_BUCKET_KEY_REGEX = re.compile(
+            r"^(?P<bucket>arn:(aws).*:s3:[a-z\-0-9]*:[0-9]{12}:accesspoint[:/][^/]+)/?"
+            r"(?P<key>.*)$"
+        )
+        _S3_OUTPOST_TO_BUCKET_KEY_REGEX = re.compile(
+            r"^(?P<bucket>arn:(aws).*:s3-outposts:[a-z\-0-9]+:[0-9]{12}:outpost[/:]"
+            r"[a-zA-Z0-9\-]{1,63}[/:](bucket|accesspoint)[/:][a-zA-Z0-9\-]{1,63})[/:]?(?P<key>.*)$"
+        )
+        match = _S3_ACCESSPOINT_TO_BUCKET_KEY_REGEX.match(s3_path)
+        if match:
+            return match.group("bucket"), match.group("key")
+        match = _S3_OUTPOST_TO_BUCKET_KEY_REGEX.match(s3_path)
+        if match:
+            return match.group("bucket"), match.group("key")
+        s3_components = s3_path.split("/", 1)
+        bucket = s3_components[0]
+        s3_key = ""
+        if len(s3_components) > 1:
+            s3_key = s3_components[1]
+        return bucket, s3_key
+
     def split_path(self, path) -> Tuple[str, str, Optional[str]]:
         """
         Normalise S3 path string into bucket and key.
@@ -385,7 +414,7 @@ def split_path(self, path) -> Tuple[str, str, Optional[str]]:
         if "/" not in path:
             return path, "", None
         else:
-            bucket, keypart = path.split("/", 1)
+            bucket, keypart = self._find_bucket_key(path)
             key, _, version_id = keypart.partition("?versionId=")
             return (
                 bucket,

s3fs/tests/test_s3fs.py

@@ -2392,3 +2392,17 @@ def test_list_del_multipart(s3):
         f.close()  # may error
     except Exception:
         pass
+
+
+def test_split_path(s3):
+    buckets = [
+        "my-test-bucket",
+        "arn:aws:s3:region:123456789012:accesspoint/my-access-point-name",
+        "arn:aws:s3-outposts:region:123456789012:outpost/outpost-id/bucket/my-test-bucket",
+        "arn:aws:s3-outposts:region:123456789012:outpost/outpost-id/accesspoint/my-accesspoint-name",
+    ]
+    test_key = "my/test/path"
+    for test_bucket in buckets:
+        bucket, key, _ = s3.split_path("s3://" + test_bucket + "/" + test_key)
+        assert bucket == test_bucket
+        assert key == test_key