From aa584381b24d8007a5831d398e9e72fa5090dcf9 Mon Sep 17 00:00:00 2001
From: keewis <keewis@users.noreply.github.com>
Date: Wed, 3 Nov 2021 17:55:54 +0100
Subject: [PATCH] fix the detection of backend entrypoints (#5931)

---
 ci/requirements/py37-bare-minimum.yml |  1 +
 ci/requirements/py37-min-all-deps.yml |  1 +
 doc/whats-new.rst                     |  2 ++
 xarray/backends/plugins.py            | 10 +++-------
 4 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/ci/requirements/py37-bare-minimum.yml b/ci/requirements/py37-bare-minimum.yml
index f9148d6dfd0..620b5057d50 100644
--- a/ci/requirements/py37-bare-minimum.yml
+++ b/ci/requirements/py37-bare-minimum.yml
@@ -13,3 +13,4 @@ dependencies:
   - numpy=1.18
   - pandas=1.1
   - typing_extensions=3.7
+  - importlib-metadata=2.0
diff --git a/ci/requirements/py37-min-all-deps.yml b/ci/requirements/py37-min-all-deps.yml
index 2d5a0f4e8d9..e62987dd31a 100644
--- a/ci/requirements/py37-min-all-deps.yml
+++ b/ci/requirements/py37-min-all-deps.yml
@@ -24,6 +24,7 @@ dependencies:
   - hdf5=1.10
   - hypothesis
   - iris=2.4
+  - importlib-metadata=2.0
   - lxml=4.6  # Optional dep of pydap
   - matplotlib-base=3.3
   - nc-time-axis=1.2
diff --git a/doc/whats-new.rst b/doc/whats-new.rst
index 06d9ea8ed40..be39cd387d8 100644
--- a/doc/whats-new.rst
+++ b/doc/whats-new.rst
@@ -31,6 +31,8 @@ Deprecations
 
 Bug fixes
 ~~~~~~~~~
+- Fix a regression in the detection of the backend entrypoints (:issue:`5930`, :pull:`5931`)
+  By `Justus Magin <https://github.com/keewis>`_.
 
 Documentation
 ~~~~~~~~~~~~~
diff --git a/xarray/backends/plugins.py b/xarray/backends/plugins.py
index b71ca7be55c..bcaee498b90 100644
--- a/xarray/backends/plugins.py
+++ b/xarray/backends/plugins.py
@@ -6,10 +6,10 @@
 from .common import BACKEND_ENTRYPOINTS, BackendEntrypoint
 
 try:
-    from importlib.metadata import Distribution
+    from importlib.metadata import entry_points
 except ImportError:
     # if the fallback library is missing, we are doomed.
-    from importlib_metadata import Distribution  # type: ignore[no-redef]
+    from importlib_metadata import entry_points  # type: ignore[no-redef]
 
 
 STANDARD_BACKENDS_ORDER = ["netcdf4", "h5netcdf", "scipy"]
@@ -99,11 +99,7 @@ def build_engines(entrypoints):
 
 @functools.lru_cache(maxsize=1)
 def list_engines():
-    entrypoints = (
-        entry_point
-        for entry_point in Distribution.from_name("xarray").entry_points
-        if entry_point.module == "xarray.backends"
-    )
+    entrypoints = entry_points().get("xarray.backends", ())
     return build_engines(entrypoints)