add __slots__ to most classes

string slicing is expensive as python copies the (immutable) string...

debian/changelog

@@ -1,11 +0,0 @@
-pqm (0.1-1) unstable; urgency=medium
-
-  * Initial release.
-
- -- Stefan Bühler <stefan.buehler@tik.uni-stuttgart.de>  Thu, 12 Jan 2023 10:14:06 +0100
-
-pqm (0.1-0) unstable; urgency=medium
-
-  * Initial release (fake ITP).
-
- -- Stefan Bühler <stefan.buehler@tik.uni-stuttgart.de>  Thu, 12 Jan 2023 10:14:05 +0100

debian/control

@@ -1,21 +0,0 @@
-Source: pqm
-Section: mail
-Priority: optional
-Maintainer: Stefan Bühler <stefan.buehler@tik.uni-stuttgart.de>
-Rules-Requires-Root: no
-Build-Depends:
- debhelper-compat (= 13),
-Standards-Version: 4.6.1
-Homepage: https://git-nks-public.tik.uni-stuttgart.de/mail/pqm
-
-Package: pqm
-Architecture: all
-Depends:
- python3:any,
- python3-trio,
- python3-pyparsing,
- python3-yaml,
- ${misc:Depends},
-Description: postfix (cluster) queue manager
- CLI tool to manage postfix queues (optionally across multiple hosts through
- ssh).

debian/copyright

@@ -1,28 +0,0 @@
-Format: https://www.debian.org/doc/packaging-manuals/copyright-format/1.0/
-Source: https://git-nks-public.tik.uni-stuttgart.de/mail/pqm
-Upstream-Name: pqm
-
-Files:
- *
-Copyright:
- 2023 Universität Stuttgart <no-support-by-mail@uni-stuttgart.de>
-License: MIT
-
-License: MIT
- Permission is hereby granted, free of charge, to any person obtaining a copy
- of this software and associated documentation files (the "Software"), to deal
- in the Software without restriction, including without limitation the rights
- to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- copies of the Software, and to permit persons to whom the Software is
- furnished to do so, subject to the following conditions:
- .
- The above copyright notice and this permission notice shall be included in all
- copies or substantial portions of the Software.
- .
- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- SOFTWARE.

debian/gbp.conf

@@ -1,5 +0,0 @@
-[DEFAULT]
-debian-branch = debian
-upstream-branch = main
-upstream-tag = v%(version)s
-pristine-tar = False

debian/pqm.docs

@@ -1,2 +0,0 @@
-README.md
-pqm.example.yaml

debian/pqm.install

@@ -1 +0,0 @@
-pqm /usr/bin

debian/pqm.lintian-overrides

@@ -1 +0,0 @@
-pqm: no-manual-page [usr/bin/pqm]

debian/rules

@@ -1,4 +0,0 @@
-#!/usr/bin/make -f
-
-%:
-	dh $@

debian/source/format

@@ -1 +0,0 @@
-3.0 (quilt)

debian/source/options

@@ -1 +0,0 @@
-extend-diff-ignore = "(^|/)(venv|.mypy_cache)(/|$)"

pqm

@@ -33,7 +33,7 @@ import yaml
 T = typing.TypeVar('T')
 
 
-@dataclasses.dataclass
+@dataclasses.dataclass(slots=True)
 class Config:
     # if not remote_sources are configured -> use local queue
     remote_sources: dict[str, str] = dataclasses.field(default_factory=dict)
@@ -157,7 +157,7 @@ async def trio_parallel_ordered(
         await tpo.close()
 
 
-@dataclasses.dataclass
+@dataclasses.dataclass(slots=True)
 class Recipient:
     """Recipient in a postfix mail"""
     address: str
@@ -184,7 +184,22 @@ class QueueName(enum.Enum):
 ALL_QUEUE_NAMES: set[QueueName] = set(QueueName)
 
 
-@dataclasses.dataclass
+def json_decode_stream(data: str):
+    decoder = json.JSONDecoder()
+    data_len = len(data)
+    data_pos = 0
+    while data_len > data_pos and data[data_len-1].isspace():
+        data_len -= 1
+    while True:
+        while data_pos < data_len and data[data_pos].isspace():
+            data_pos += 1
+        if data_pos >= data_len:
+            return
+        obj, data_pos = decoder.raw_decode(data, data_pos)
+        yield obj
+
+
+@dataclasses.dataclass(slots=True)
 class Mail:
     """Metadata for mail in postfix queue"""
     queue_name: QueueName
@@ -209,11 +224,7 @@ class Mail:
     @staticmethod
     def read_postqueue_json(data: str, id_prefix: str = '') -> list[Mail]:
         queue = []
-        decoder = json.JSONDecoder()
+        for obj in json_decode_stream(data):
-        data = data.strip()
-        while data:
-            obj, end = decoder.raw_decode(data, 0)
-            data = data[end:].lstrip()
             mail = Mail.from_json(obj)
             mail.queue_id = id_prefix + mail.queue_id
             queue.append(mail)
@@ -222,6 +233,8 @@ class Mail:
 
 # abstract collection/cluster of postfix nodes (or just a single one)
 class Source(abc.ABC):
+    __slots__ = ()
+
     # list of server names in collection
     @abc.abstractmethod
     def server_list(self) -> list[str]:
@@ -320,6 +333,8 @@ class Source(abc.ABC):
 
 
 class LocalSource(Source):
+    __slots__ = ()
+
     def server_list(self) -> list[str]:
         return [socket.gethostname()]
 
@@ -377,6 +392,8 @@ class LocalSource(Source):
 
 
 class RemoteSource(Source):
+    __slots__ = ('remotes',)
+
     def __init__(self, remotes: dict[str, str]) -> None:
         super().__init__()
         self.remotes = remotes
@@ -509,6 +526,8 @@ class RemoteSource(Source):
 
 
 class UserActivityStats:
+    __slots__ = ('count_mails', 'related_mails', 'cut_off')
+
     # find most active address for `health` command
 
     def __init__(self, cut_off: int = 10) -> None:
@@ -577,6 +596,8 @@ class UserActivityStats:
 class Filter(abc.ABC):
     """abstract base class for filter expressions"""
 
+    __slots__ = ()
+
     def __init__(self) -> None:
         pass
 
@@ -639,11 +660,14 @@ class Filter(abc.ABC):
 
 # abstract base class for filters that don't need (...) around in representations of members in combined filters
 class SingleExprFilter(Filter):
-    pass
+    __slots__ = ()
 
 
 class FalseFilter(SingleExprFilter):
     """constant false - matches no mail"""
+
+    __slots__ = ()
+
     def __repr__(self) -> str:
         return '0'
 
@@ -669,6 +693,9 @@ class FalseFilter(SingleExprFilter):
 
 class TrueFilter(SingleExprFilter):
     """constant true - matches all mail"""
+
+    __slots__ = ()
+
     def __repr__(self) -> str:
         return '1'
 
@@ -697,6 +724,8 @@ TRUE_FILTER = TrueFilter()
 
 
 class AndFilter(Filter):
+    __slots__ = ('expressions',)
+
     def __init__(self, expressions: list[Filter] | tuple[()] = ()) -> None:
         super().__init__()
         self.expressions: list[Filter] = expressions or []
@@ -750,6 +779,8 @@ class AndFilter(Filter):
 
 
 class OrFilter(Filter):
+    __slots__ = ('expressions',)
+
     def __init__(self, expressions: list[Filter] | tuple[()] = ()) -> None:
         super().__init__()
         self.expressions: list[Filter] = expressions or []
@@ -803,6 +834,8 @@ class OrFilter(Filter):
 
 
 class NotFilter(SingleExprFilter):
+    __slots__ = ('expression',)
+
     def __init__(self, expression: Filter) -> None:
         super().__init__()
         self.expression = expression
@@ -840,6 +873,9 @@ class NotFilter(SingleExprFilter):
 
 class QueueFilter(SingleExprFilter):
     """match mails based on queue they are in"""
+
+    __slots__ = ('select',)
+
     def __init__(self, select: list[QueueName]) -> None:
         self.select = set(select)
 
@@ -898,6 +934,8 @@ class AddressSelector(enum.Enum):
 
 
 class BaseAddressPattern(abc.ABC):
+    __slots__ = ()
+
     # abstract base class of patterns to use to match a mail address
     # subclasses match either: full address, domain part, regex
     def __init__(self) -> None:
@@ -930,6 +968,8 @@ class BaseAddressPattern(abc.ABC):
 
 
 class AddressPattern(BaseAddressPattern):
+    __slots__ = ('address',)
+
     # match full address exactly
     def __init__(self, address: str) -> None:
         super().__init__()
@@ -952,6 +992,8 @@ class AddressPattern(BaseAddressPattern):
 
 
 class AddressDomainPattern(BaseAddressPattern):
+    __slots__ = ('domain',)
+
     # match address by domain
     def __init__(self, domain: str) -> None:
         super().__init__()
@@ -969,6 +1011,8 @@ class AddressDomainPattern(BaseAddressPattern):
 
 
 class AddressRegexMatch(BaseAddressPattern):
+    __slots__ = ('address',)
+
     # match address by regex
     def __init__(self, address: str | re.Pattern[str]) -> None:
         super().__init__()
@@ -990,6 +1034,8 @@ class AddressRegexMatch(BaseAddressPattern):
 
 
 class AddressFilter(SingleExprFilter):
+    __slots__ = ('selector', 'patterns')
+
     # match mails by address
     def __init__(self, selector: AddressSelector, patterns: list[BaseAddressPattern]) -> None:
         self.selector = selector