21020: Make arvados.api.http_cache get a path from the environment

[arvados.git] / sdk / python / arvados / api.py

diff --git a/sdk/python/arvados/api.py b/sdk/python/arvados/api.py
index ca9f17f8661ebffae7203af458dc5b83eb6b68f7..6b6ee36b3ecb7ed803ac4cb6075254ba2439e074 100644 (file)
--- a/sdk/python/arvados/api.py
+++ b/sdk/python/arvados/api.py
@@ -9,12 +9,7 @@ niceties such as caching, X-Request-Id header for tracking, and more. The main
 client constructors are `api` and `api_from_config`.
 """
 
-from __future__ import absolute_import
-from future import standard_library
-standard_library.install_aliases()
-from builtins import range
 import collections
-import http.client
 import httplib2
 import json
 import logging
@@ -28,6 +23,14 @@ import threading
 import time
 import types
 
+from typing import (
+    Any,
+    Dict,
+    List,
+    Mapping,
+    Optional,
+)
+
 import apiclient
 import apiclient.http
 from apiclient import discovery as apiclient_discovery
@@ -152,43 +155,40 @@ def _new_http_error(cls, *args, **kwargs):
         errors.ApiError, *args, **kwargs)
 apiclient_errors.HttpError.__new__ = staticmethod(_new_http_error)
 
-def http_cache(data_type):
+def http_cache(data_type: str) -> cache.SafeHTTPCache:
     """Set up an HTTP file cache
 
     This function constructs and returns an `arvados.cache.SafeHTTPCache`
-    backed by the filesystem under `~/.cache/arvados/`, or `None` if the
-    directory cannot be set up. The return value can be passed to
+    backed by the filesystem under a cache directory from the environment, or
+    `None` if the directory cannot be set up. The return value can be passed to
     `httplib2.Http` as the `cache` argument.
 
     Arguments:
 
-    * data_type: str --- The name of the subdirectory under `~/.cache/arvados`
+    * data_type: str --- The name of the subdirectory
       where data is cached.
     """
     try:
-        homedir = pathlib.Path.home()
-    except RuntimeError:
-        return None
-    path = pathlib.Path(homedir, '.cache', 'arvados', data_type)
-    try:
-        path.mkdir(parents=True, exist_ok=True)
-    except OSError:
+        path = util._BaseDirectories('CACHE').storage_path() / data_type
+        path.mkdir(exist_ok=True)
+    except (OSError, RuntimeError):
         return None
-    return cache.SafeHTTPCache(str(path), max_age=60*60*24*2)
+    else:
+        return cache.SafeHTTPCache(str(path), max_age=60*60*24*2)
 
 def api_client(
-        version,
-        discoveryServiceUrl,
-        token,
+        version: str,
+        discoveryServiceUrl: str,
+        token: str,
         *,
-        cache=True,
-        http=None,
-        insecure=False,
-        num_retries=10,
-        request_id=None,
-        timeout=5*60,
-        **kwargs,
-):
+        cache: bool=True,
+        http: Optional[httplib2.Http]=None,
+        insecure: bool=False,
+        num_retries: int=10,
+        request_id: Optional[str]=None,
+        timeout: int=5*60,
+        **kwargs: Any,
+) -> apiclient_discovery.Resource:
     """Build an Arvados API client
 
     This function returns a `googleapiclient.discovery.Resource` object
@@ -208,8 +208,7 @@ def api_client(
     Keyword-only arguments:
 
     * cache: bool --- If true, loads the API discovery document from, or
-      saves it to, a cache on disk (located at
-      `~/.cache/arvados/discovery`).
+      saves it to, a cache on disk.
 
     * http: httplib2.Http | None --- The HTTP client object the API client
       object will use to make requests.  If not provided, this function will
@@ -232,7 +231,6 @@ def api_client(
 
     Additional keyword arguments will be passed directly to
     `googleapiclient.discovery.build`.
-
     """
     if http is None:
         http = httplib2.Http(
@@ -294,12 +292,12 @@ def api_client(
     return svc
 
 def normalize_api_kwargs(
-        version=None,
-        discoveryServiceUrl=None,
-        host=None,
-        token=None,
-        **kwargs,
-):
+        version: Optional[str]=None,
+        discoveryServiceUrl: Optional[str]=None,
+        host: Optional[str]=None,
+        token: Optional[str]=None,
+        **kwargs: Any,
+) -> Dict[str, Any]:
     """Validate kwargs from `api` and build kwargs for `api_client`
 
     This method takes high-level keyword arguments passed to the `api`
@@ -352,7 +350,11 @@ def normalize_api_kwargs(
         **kwargs,
     }
 
-def api_kwargs_from_config(version=None, apiconfig=None, **kwargs):
+def api_kwargs_from_config(
+        version: Optional[str]=None,
+        apiconfig: Optional[Mapping[str, str]]=None,
+        **kwargs: Any
+) -> Dict[str, Any]:
     """Build `api_client` keyword arguments from configuration
 
     This function accepts a mapping with Arvados configuration settings like
@@ -395,9 +397,18 @@ def api_kwargs_from_config(version=None, apiconfig=None, **kwargs):
         **kwargs,
     )
 
-def api(version=None, cache=True, host=None, token=None, insecure=False,
-        request_id=None, timeout=5*60, *,
-        discoveryServiceUrl=None, **kwargs):
+def api(
+        version: Optional[str]=None,
+        cache: bool=True,
+        host: Optional[str]=None,
+        token: Optional[str]=None,
+        insecure: bool=False,
+        request_id: Optional[str]=None,
+        timeout: int=5*60,
+        *,
+        discoveryServiceUrl: Optional[str]=None,
+        **kwargs: Any,
+) -> 'arvados.safeapi.ThreadSafeApiCache':
     """Dynamically build an Arvados API client
 
     This function provides a high-level "do what I mean" interface to build an
@@ -449,7 +460,11 @@ def api(version=None, cache=True, host=None, token=None, insecure=False,
     from .safeapi import ThreadSafeApiCache
     return ThreadSafeApiCache({}, {}, kwargs, version)
 
-def api_from_config(version=None, apiconfig=None, **kwargs):
+def api_from_config(
+        version: Optional[str]=None,
+        apiconfig: Optional[Mapping[str, str]]=None,
+        **kwargs: Any
+) -> 'arvados.safeapi.ThreadSafeApiCache':
     """Build an Arvados API client from a configuration mapping
 
     This function builds an Arvados API client from a mapping with user