alot/settings: Use notmuch config to read configuration

The main benefit from this is that we get the defaults directly from
notmuch and do not risk using inconsistent configuration values.

A good example of this is getting the database path. Getting the path
directly from the notmuch config file is not enough, because the user
might be using the default location with no explicit entry in the file.
Since notmuch does is a bit of logic notmuch to get the database path
(see section "DATABASE LOCATION" in man page for notmuch-config(1)), it
is better to get it directly from "notmuch config".

Since get_notmuch_setting() now always returns a string, also refactor
the call to settings.get_notmuch_setting('maildir', 'synchronize_flags')
for this new reality.

alot/db/manager.py

@@ -72,7 +72,7 @@ def flush(self):
             raise DatabaseROError()
         if self.writequeue:
             # read notmuch's config regarding imap flag synchronization
-            sync = settings.get_notmuch_setting('maildir', 'synchronize_flags')
+            sync = settings.get_notmuch_setting('maildir', 'synchronize_flags') == 'true'
 
             # go through writequeue entries
             while self.writequeue:

alot/settings/manager.py

@@ -17,7 +17,7 @@
 from ..utils import configobj as checks
 
 from .errors import ConfigError, NoMatchingAccount
-from .utils import read_config
+from .utils import read_config, read_notmuch_config
 from .utils import resolve_att
 from .theme import Theme
 
@@ -36,12 +36,13 @@ def __init__(self):
         self._accounts = None
         self._accountmap = None
         self._notmuchconfig = None
+        self._notmuchconfig_path = None
         self._config = ConfigObj()
         self._bindings = None
 
     def reload(self):
         """Reload notmuch and alot config files"""
-        self.read_notmuch_config(self._notmuchconfig.filename)
+        self.read_notmuch_config(self._notmuchconfig_path)
         self.read_config(self._config.filename)
 
     def read_notmuch_config(self, path):
@@ -50,8 +51,8 @@ def read_notmuch_config(self, path):
         :param path: path to notmuch's config file
         :type path: str
         """
-        spec = os.path.join(DEFAULTSPATH, 'notmuch.rc.spec')
-        self._notmuchconfig = read_config(path, spec)
+        self._notmuchconfig = read_notmuch_config(path)
+        self._notmuchconfig_path = path  # Set the path *after* succesful read.
 
     def _update_bindings(self, newbindings):
         assert isinstance(newbindings, Section)
@@ -275,7 +276,8 @@ def get_notmuch_setting(self, section, key, fallback=None):
         :type key: str
         :param fallback: fallback returned if key is not present
         :type fallback: str
-        :returns: config value with type as specified in the spec-file
+        :returns: the config value
+        :rtype: str
         """
         value = None
         if section in self._notmuchconfig:

alot/settings/utils.py

@@ -9,6 +9,7 @@
 from urwid import AttrSpec
 
 from .errors import ConfigError
+from ..helper import call_cmd
 
 
 def read_config(configpath=None, specpath=None, checks=None,
@@ -82,6 +83,40 @@ def read_config(configpath=None, specpath=None, checks=None,
     return config
 
 
+def read_notmuch_config(path):
+    """
+    Read notmuch configuration.
+
+    This function calls the command "notmuch --config {path} config list" and
+    parses its output into a ``config`` dictionary, which is then returned.
+
+    The configuration value for a key under a section can be accessed with
+    ``config[section][key]``.
+
+    The returned value is a dict ``config`` with
+
+    :param path: path to the configuration file, which is passed as
+        argument to the --config option of notmuch.
+    :type path: str
+    :raises: :class:`~alot.settings.errors.ConfigError`
+    :rtype: `dict`
+    """
+    cmd = ['notmuch', '--config', path, 'config', 'list']
+    out, err, code = call_cmd(cmd)
+    if code != 0:
+        msg = f'failed to read notmuch config with command {cmd} (exit error: {code}):\n{err}'
+        logging.error(msg)
+        raise ConfigError(msg)
+
+    config = {}
+    for line in out.splitlines():
+        left_hand, right_hand = line.split("=", maxsplit=1)
+        section, key = left_hand.split(".", maxsplit=1)
+        config.setdefault(section, {})[key] = right_hand
+
+    return config
+
+
 def resolve_att(a, fallback):
     """ replace '' and 'default' by fallback values """
     if a is None:

setup.py

@@ -31,7 +31,6 @@
     package_data={
         'alot': [
             'defaults/alot.rc.spec',
-            'defaults/notmuch.rc.spec',
             'defaults/abook_contacts.spec',
             'defaults/default.theme',
             'defaults/default.bindings',