xju 1.4.0

xju library

Various modules implemented to some broad principles:

• fine-grained static typing

• pure context management

• useful functionality that is hard to use incorrectly

• 100% test coverage

(see the bottom of this readme for release history)

xju.newtype - static and dynamic distinct int, float and str types

• unlike typing.NewType the new types are compatible with isinstance, so you can actually use them to do real stuff, like implement overloaded methods

• see xju/newtype.py.test for sample code

xju.cmc - context management

• unlike python standard library e.g. open(), these are “pure” context managers: resources are never acquired until __enter__

xju.cmc.cmclass - provides context management for class attributes that are context managers

• managing multiple resource attributes is clumsy with ExitStack, this module implements __enter__ and __exit__ automatically to ensure correct ordering and cleanup on exceptions

• see xju/cmc/cmclass.py.test for sample code

xju.cmc.Dict - dictionary that is a context manager for its (context manager) values

• see xju/cmc/Dict.py.test for sample code

xju.cmc.Opt - context manager for its optional (context manager) value

• see xju/cmc/Opt.py.test for sample code

xju.cmc.async_cmclass - provides async context management for class attributes that are async / sync context managers

• managing multiple resource attributes is clumsy with AsyncExitStack, this module implements __aenter__ and __aexit__ automatically to ensure correct ordering and cleanup on exceptions

• see xju/cmc/async_cmclass.py.test for sample code

xju.cmc.AsyncDict - dictionary that is a async context manager for its (async context manager) values

• see xju/cmc/AsyncDict.py.test for sample code

xju.cmc.AsyncOpt - async context manager for its optional (async context manager) value

• see xju/cmc/AsyncOpt.py.test for sample code

xju.cmc.io - pure context management for e.g. file reading and writing, non-blocking io

• see unit tests for sample code: * FileLock.py.test * FileMode.py.test * FilePosition.py.test * FileReader.py.test * FileWriter.py.test * UnixStreamListener.py.test * UnixStreamSocket.py.test * Pipe.py.test

xju.cmc.tstore

• time-based storage, organised as files covering time-ranges

• see xju/cmc/tstore.py.test for sample code

xju.cmc.perflog

• time-based json-format record storage built on xju.cmc.tstore

xju.cmc.Thread/Mutex/Lock/Condition

• threading primitives that encourage correct design

• see xju/cmc/ThreadMutexLockCondition.py.test for sample code

xju.cmc.AsyncTask/Mutex/Lock/Condition

• asyncio Task/Mutex/Lock/Condition context managers

• see xju/cmc/Task.py.test for sample code

xju.cmc.AsyncServiceQueue

• asyncio thread-safe service queue, allows any thread to queue a coroutine on an event loop so it is executed by a task in that event loop

• see xju/cmc/AsyncServiceQueue.py.test for sample code

xju.pq

• jquery-like html inspection and modification

• see xju/pq.py.test for sample code

xju.assert_

• assert functions that capture term values e.g. x and y in Assert(x)==y

• see xju/assert_.py.test for sample code

xju.cmd

• wrapper for subprocess.Popen that captures very common usage without the option-and-flag-warren of subprocess

• see xju/cmd.py.test for sample code

xju.json_codec

• encoding/decoding type-hinted dict/list/int/bool/None/float/str/Enum and classes to and from json

• designed to fit well with type checking

• built in support for xju.newtype described above

• generates json schema equivalent schemas for types

• generates typescript code (types, type-guards and dynamic casts) equivalents

• extensible with custom encodings

• see xju/json_codec.py.test for full sample code

xju.jsonschema

• represents JSON schemas as straight-foward, easy-to-read python data structures, because life’s too short for jsonschema.org

• see xju/jsonschema.py.test for sample code

xju.patch

• minimal, simple, direct patching(/stub/mock) utility, unlike mock-warren. Because one shouldn’t need a degree to read and write a unit test

• see xju/patch.py.test for sample code

xju.time

• type-safe time and duration classes

• see xju/time.py.test for sample code

xju.xn

• Exception wrapping to provide human readable context gathering

• see xju/xn.py.test for sample code

Release History

• 1.4.0 add Enum support to xju.json_codec

• 1.3.0 add xju.cmc.AsyncDict, like xju.cmc.Dict but async

• 1.3.0 xju.cmc.AsyncOpt/Opt async context manager that holds an optional async context manager

• 1.3.0 xju.cmc.Opt context manager that holds an optional context manager

• 1.3.0 python xju.cmc add async_cmclass, like xju.cmc.cmclass; handles both async and non-async attrs

• 1.3.0 strip leading whitespace from doc strings, for compatibility with code formatters like black

• 1.2.13 xju.newtype Literals now handle more than one value, e.g. Literal[‘fred’,’jock’]

• 1.2.13 xju.newtype eq/neq now follows python “you can compare apples to oranges”, rely on mypy –strict-equality (which for what it’s worth is broken at mypy 1.3.0)

• 1.2.13 now compatible with mypy –strict-equality

• 1.2.13 add xju.cmc.AsyncTask/Mutex/Condition/Lock (thread equivalents for asyncio); note Task deprecated, use AsyncTask

• 1.2.13 add custom encoding facility to xju.json_codec

• 1.2.13 add typescript aliases to json_codec generated code for xju.newtype Str/Int/Float

• 1.2.12 fixes typescript null v object handling

• 1.2.12 adds typescript aliases for NewStr, NewInt, NewFloat

• 1.2.11 adds typescript –strict support and fixes typescript code generation bugs

• 1.2.11 xju.json_codec supports Literal[int] and Literal[bool]

• 1.2.11 xju.json_codec supports generic classes

• 1.2.10 xju.json_codec supports typing.NewType str/int/bool/float

• 1.2.9 xju.json_codec generates typescript equivalents

• 1.2.9 xju.json_codec adds codec() convenience method

• 1.2.9 xju.json_codec uses kw_args to construct classes

• 1.2.8 xju.json_codec supports string type-hints (for foward definitions)

• 1.2.8 xju.json_codec adds typing.Self support (for recursive types)

• 1.2.8 xju.json_codec requires python 3.11, tested with mypy 1.1.1