Use env var IPA_CONFDIR to get confdir

The environment variable IPA_CONFDIR overrides the default confdir path.
The value of the environment variable must be an absolute path to an existing
directory. The new variable makes it much simpler to use the 'ipa'
command and ipalib with a local configuration directory.

Some scripts (e.g. servers, installers, and upgrades) set the confdir
explicitly and do not support the env var.

Signed-off-by: Christian Heimes <cheimes@redhat.com>
Reviewed-By: Jan Cholasta <jcholast@redhat.com>

client/man/ipa.1

@@ -186,6 +186,10 @@ The ipa client will determine which server to connect to in this order:
 
 .TP
 If a kerberos error is raised by any of the requests then it will stop processing and display the error message.
+.SH "ENVIRONMENT VARIABLES"
+.TP
+\fBIPA_CONFDIR\fR
+Override path to confdir (default: \fB/etc/ipa\fR).
 .SH "FILES"
 .TP
 \fB/etc/ipa/default.conf\fR

ipalib/config.py

@@ -43,6 +43,7 @@ from ipapython.dn import DN
 from ipalib.base import check_name
 from ipalib.constants import CONFIG_SECTION
 from ipalib.constants import OVERRIDE_ERROR, SET_ERROR, DEL_ERROR
+from ipapython.admintool import ScriptError
 
 if six.PY3:
     unicode = str
@@ -460,8 +461,17 @@ class Env(object):
             self.context = 'default'
 
         # Set confdir:
+        self.env_confdir = os.environ.get('IPA_CONFDIR')
         if 'confdir' not in self:
-            if self.in_tree:
+            if self.env_confdir is not None:
+                if (not path.isabs(self.env_confdir)
+                        or not path.isdir(self.env_confdir)):
+                    raise ScriptError(
+                        "IPA_CONFDIR env var must be an absolute path to an "
+                        "existing directory, got '{}'.".format(
+                            self.env_confdir))
+                self.confdir = self.env_confdir
+            elif self.in_tree:
                 self.confdir = self.dot_ipa
             else:
                 self.confdir = path.join('/', 'etc', 'ipa')

ipalib/plugable.py

@@ -713,6 +713,15 @@ class API(ReadOnly):
         self.__doing('finalize')
         self.__do_if_not_done('load_plugins')
 
+        if self.env.env_confdir is not None:
+            if self.env.env_confdir == self.env.confdir:
+                self.log.info(
+                    "IPA_CONFDIR env sets confdir to '%s'.", self.env.confdir)
+            else:
+                self.log.warn(
+                    "IPA_CONFDIR env is overridden by an explicit confdir "
+                    "argument.")
+
         for plugin in self.__plugins:
             if not self.env.validate_api:
                 if plugin.full_name not in DEFAULT_PLUGINS:

ipatests/test_ipalib/test_plugable.py

@@ -24,9 +24,13 @@ Test the `ipalib.plugable` module.
 # FIXME: Pylint errors
 # pylint: disable=no-member
 
+import os
+import textwrap
+
+from ipalib import plugable, errors, create_api
+from ipapython.admintool import ScriptError
 from ipatests.util import raises, read_only
-from ipatests.util import ClassChecker, create_test_api
-from ipalib import plugable, errors
+from ipatests.util import ClassChecker, create_test_api, TempHome
 
 import pytest
 
@@ -272,3 +276,35 @@ class test_API(ClassChecker):
         assert o.isdone('load_plugins') is True
         e = raises(Exception, o.load_plugins)
         assert str(e) == 'API.load_plugins() already called'
+
+    def test_ipaconf_env(self):
+        ipa_confdir = os.environ.get('IPA_CONFDIR', None)
+        try:
+            with TempHome() as home:
+                defaultconf = home.join('default.conf')
+                with open(defaultconf, 'w') as f:
+                    f.write(textwrap.dedent("""
+                        [global]
+                        basedn = dc=ipa,dc=test
+                        realm = IPA.TEST
+                        domain = ipa.test
+                        """)
+                    )
+                os.environ['IPA_CONFDIR'] = home.path
+                api = create_api(mode='unit_test')
+                api.bootstrap()
+                api.finalize()
+                assert api.env.confdir == home.path
+                assert api.env.conf_default == defaultconf
+                assert api.env.realm == 'IPA.TEST'
+                assert api.env.domain == 'ipa.test'
+
+                os.environ['IPA_CONFDIR'] = home.join('invalid')
+                api = create_api(mode='unit_test')
+                with pytest.raises(ScriptError):
+                    api.bootstrap()
+        finally:
+            if ipa_confdir:
+                os.environ['IPA_CONFDIR'] = ipa_confdir
+            else:
+                os.environ.pop('IPA_CONFDIR')

ipatests/util.py

@@ -96,6 +96,12 @@ class TempDir(object):
     def __del__(self):
         self.rmtree()
 
+    def __enter__(self):
+        return self
+
+    def __exit__(self, exc_type, exc_val, exc_tb):
+        self.rmtree()
+
 
 class TempHome(TempDir):
     def __init__(self):