Move dogpile cache and URLShortener to services

I can see why this was originally in db because it does touch the
filesystem but it is pretty unrelated to the rest of the module and is
only used by services.

bugwarrior/db.py

@@ -1,10 +1,7 @@
 import json
-import os
 import re
 import subprocess
 
-import requests
-import dogpile.cache
 from taskw import TaskWarriorShellout
 from taskw.exceptions import TaskwarriorError
 
@@ -15,35 +12,6 @@
 log = logging.getLogger(__name__)
 
 
-DOGPILE_CACHE_PATH = os.path.expanduser(''.join([
-    os.getenv('XDG_CACHE_HOME', '~/.cache'), '/dagd-py3.dbm']))
-
-if not os.path.isdir(os.path.dirname(DOGPILE_CACHE_PATH)):
-    os.makedirs(os.path.dirname(DOGPILE_CACHE_PATH))
-CACHE_REGION = dogpile.cache.make_region().configure(
-    "dogpile.cache.dbm",
-    arguments=dict(filename=DOGPILE_CACHE_PATH),
-)
-
-
-class URLShortener:
-    _instance = None
-
-    def __new__(cls, *args, **kwargs):
-        if not cls._instance:
-            cls._instance = super().__new__(
-                cls, *args, **kwargs
-            )
-        return cls._instance
-
-    @CACHE_REGION.cache_on_arguments()
-    def shorten(self, url):
-        if not url:
-            return ''
-        base = 'https://da.gd/s'
-        return requests.get(base, params=dict(url=url)).text.strip()
-
-
 class NotFound(Exception):
     pass
 

bugwarrior/services/__init__.py

@@ -1,20 +1,49 @@
 import abc
 import copy
+import os
 import re
 
 from dateutil.parser import parse as parse_date
 from dateutil.tz import tzlocal
+import dogpile.cache
 from jinja2 import Template
 import pytz
+import requests
 
 from taskw.task import Task
 
 from bugwarrior.config import schema, secrets
-from bugwarrior.db import URLShortener
 
 import logging
 log = logging.getLogger(__name__)
 
+DOGPILE_CACHE_PATH = os.path.expanduser(''.join([
+    os.getenv('XDG_CACHE_HOME', '~/.cache'), '/dagd-py3.dbm']))
+
+if not os.path.isdir(os.path.dirname(DOGPILE_CACHE_PATH)):
+    os.makedirs(os.path.dirname(DOGPILE_CACHE_PATH))
+CACHE_REGION = dogpile.cache.make_region().configure(
+    "dogpile.cache.dbm",
+    arguments=dict(filename=DOGPILE_CACHE_PATH),
+)
+
+class URLShortener:
+    _instance = None
+
+    def __new__(cls, *args, **kwargs):
+        if not cls._instance:
+            cls._instance = super().__new__(
+                cls, *args, **kwargs
+            )
+        return cls._instance
+
+    @CACHE_REGION.cache_on_arguments()
+    def shorten(self, url):
+        if not url:
+            return ''
+        base = 'https://da.gd/s'
+        return requests.get(base, params=dict(url=url)).text.strip()
+
 
 def get_processed_url(main_config: schema.MainSectionConfig, url: str):
     """ Returns a URL with conditional processing.

bugwarrior/services/taiga.py

@@ -2,8 +2,7 @@
 import typing_extensions
 
 from bugwarrior import config
-from bugwarrior.db import CACHE_REGION as cache
-from bugwarrior.services import IssueService, Issue, ServiceClient
+from bugwarrior.services import IssueService, Issue, ServiceClient, CACHE_REGION as cache
 
 import logging
 log = logging.getLogger(__name__)