Fix leftover directories in /tmp after tests

The way wms_cache was set previously made it so that after each tests
run there would be one or more directories leftover in /tmp. This also
happened for each start of MSUI. This change makes MSUI use the
platform-specific cache directory of the user instead and sets
XDG_CACHE_HOME to isolate those between test runs.

mslib/msui/constants.py

@@ -30,6 +30,7 @@
 import fs
 import os
 import logging
+import platformdirs
 
 # ToDo refactor to generic functions, keep only constants
 HOME = os.path.expanduser(f"~{os.path.sep}")
@@ -39,6 +40,8 @@
 # MSUI does not actually support any PyFilesystem2 fs that is not available as a local path
 MSUI_CONFIG_SYSPATH = _fs.getsyspath("")
 
+MSUI_CACHE_PATH = platformdirs.user_cache_path("msui", "mss")
+
 GRAVATAR_DIR_PATH = fs.path.join(MSUI_CONFIG_PATH, "gravatars")
 
 MSUI_SETTINGS = os.getenv('MSUI_SETTINGS', os.path.join(MSUI_CONFIG_PATH, "msui_settings.json"))

mslib/utils/config.py

@@ -32,7 +32,6 @@
 import logging
 import fs
 import os
-import tempfile
 
 from mslib.utils import FatalUserError
 from mslib.msui import constants
@@ -149,8 +148,7 @@ class MSUIDefaultConfig:
     WMS_preload = []
 
     # WMS image cache settings:
-    # this changes on any start of msui, use ths msui_settings.json when you want a persistent path
-    wms_cache = os.path.join(tempfile.TemporaryDirectory().name, "msui_wms_cache")
+    wms_cache = str(constants.MSUI_CACHE_PATH / "wms_cache")
 
     # Maximum size of the cache in bytes.
     wms_cache_max_size_bytes = 20 * 1024 * 1024

tests/constants.py

@@ -27,6 +27,7 @@
 
 import os
 import fs
+import tempfile
 from fs.tempfs import TempFS
 
 try:
@@ -60,6 +61,9 @@
 os.environ["MSUI_CONFIG_PATH"] = MSUI_CONFIG_PATH
 SERVER_CONFIG_FILE_PATH = fs.path.join(SERVER_CONFIG_FS.getsyspath(""), SERVER_CONFIG_FILE)
 
+_xdg_cache_home_temporary_directory = tempfile.TemporaryDirectory()
+os.environ["XDG_CACHE_HOME"] = _xdg_cache_home_temporary_directory.name
+
 # we keep DATA_DIR until we move netCDF4 files to pyfilesystem2
 DATA_DIR = DATA_FS.getsyspath("")