From 828baff301445a0a47b968681b5aec5079d95105 Mon Sep 17 00:00:00 2001
From: vincentsarago <vincent.sarago@gmail.com>
Date: Tue, 23 Apr 2024 14:00:33 +0200
Subject: [PATCH] refactor assert

---
 .pre-commit-config.yaml      |  1 +
 pyproject.toml               |  6 +++---
 titiler/xarray/main.py       | 13 +------------
 titiler/xarray/reader.py     | 15 ++-------------
 titiler/xarray/redis_pool.py | 23 ++++++++++++++++++++---
 5 files changed, 27 insertions(+), 31 deletions(-)

diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 6d84490..e6ef50a 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -30,3 +30,4 @@ repos:
         exclude: tests/.*
         additional_dependencies:
         - types-attrs
+        - types-redis
diff --git a/pyproject.toml b/pyproject.toml
index db844d3..bfd8073 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -30,9 +30,9 @@ dependencies = [
     "xarray==2024.3.0",
     "rioxarray==0.15.0",
     "zarr==2.17.2",
-    "fsspec==2024.3.1",
-    "s3fs==2024.3.1",
-    "aiohttp==3.9.5",
+    "fsspec",
+    "s3fs",
+    "aiohttp",
     "requests==2.31.0",
     "pydantic==2.0.2",
     "titiler.core==0.14.1",
diff --git a/titiler/xarray/main.py b/titiler/xarray/main.py
index 233289d..8065fc3 100644
--- a/titiler/xarray/main.py
+++ b/titiler/xarray/main.py
@@ -1,7 +1,6 @@
 """titiler app."""
 
 import logging
-from typing import Any, Callable, Optional
 
 import rioxarray
 import zarr
@@ -22,14 +21,6 @@
 from titiler.xarray.middleware import ServerTimingMiddleware
 from titiler.xarray.settings import ApiSettings
 
-get_redis: Optional[Callable[[], Any]]
-
-try:
-    from titiler.xarray.redis_pool import get_redis
-except ImportError:
-    get_redis = None
-
-
 logging.getLogger("botocore.credentials").disabled = True
 logging.getLogger("botocore.utils").disabled = True
 logging.getLogger("rio-tiler").setLevel(logging.ERROR)
@@ -107,9 +98,7 @@ def ping():
 
 if api_settings.enable_cache:
 
-    assert (
-        get_redis is not None
-    ), "`redis` must be installed to enable caching. Please install titiler-xarray with the `cache` optional dependencies that include `redis`."
+    from titiler.xarray.redis_pool import get_redis
 
     @app.get("/clear_cache")
     def clear_cache(cache_client=Depends(get_redis)):
diff --git a/titiler/xarray/reader.py b/titiler/xarray/reader.py
index d999c9e..dcdd286 100644
--- a/titiler/xarray/reader.py
+++ b/titiler/xarray/reader.py
@@ -3,7 +3,7 @@
 import contextlib
 import pickle
 import re
-from typing import Any, Callable, Dict, List, Optional
+from typing import Any, Dict, List, Optional
 
 import attr
 import fsspec
@@ -16,15 +16,9 @@
 from rio_tiler.io.xarray import XarrayReader
 from rio_tiler.types import BBox
 
+from titiler.xarray.redis_pool import get_redis
 from titiler.xarray.settings import ApiSettings
 
-get_redis: Optional[Callable[[], Any]]
-try:
-    from titiler.xarray.redis_pool import get_redis
-except ImportError:
-    get_redis = None
-
-
 api_settings = ApiSettings()
 
 
@@ -95,11 +89,6 @@ def xarray_open_dataset(
     """Open dataset."""
     # Generate cache key and attempt to fetch the dataset from cache
     if api_settings.enable_cache:
-
-        assert (
-            get_redis is not None
-        ), "`redis` must be installed to enable caching. Please install titiler-xarray with the `cache` optional dependencies that include `redis`."
-
         cache_client = get_redis()
         cache_key = f"{src_path}_{group}" if group is not None else src_path
         data_bytes = cache_client.get(cache_key)
diff --git a/titiler/xarray/redis_pool.py b/titiler/xarray/redis_pool.py
index 2c26d0c..11ac563 100644
--- a/titiler/xarray/redis_pool.py
+++ b/titiler/xarray/redis_pool.py
@@ -1,13 +1,20 @@
 """ Redis singleton class. """
 import os
 
-import fakeredis
-import redis  # type: ignore
-
 from titiler.xarray.settings import ApiSettings
 
 api_settings = ApiSettings()
 
+try:
+    import redis
+except ImportError:
+    redis = None  # type: ignore
+
+try:
+    import fakeredis
+except ImportError:
+    fakeredis = None
+
 
 class RedisCache:
     """Redis connection pool singleton class."""
@@ -17,6 +24,11 @@ class RedisCache:
     @classmethod
     def get_instance(cls):
         """Get the redis connection pool."""
+
+        assert (
+            redis
+        ), "`redis` must be installed to enable caching. Please install titiler-xarray with the `cache` optional dependencies that include `redis`."
+
         if cls._instance is None:
             cls._instance = redis.ConnectionPool(
                 host=api_settings.cache_host, port=6379, db=0
@@ -27,6 +39,11 @@ def get_instance(cls):
 def get_redis():
     """Get a redis connection."""
     if os.getenv("TEST_ENVIRONMENT"):
+
+        assert (
+            fakeredis
+        ), "`fakeredis` must be installed to enable caching in test environment. Please install titiler-xarray with the `dev` optional dependencies that include `fakeredis`."
+
         server = fakeredis.FakeServer()
         # Use fakeredis in a test environment
         return fakeredis.FakeRedis(server=server)