feat: improve typing definitions, introduce mypy in CI

[o-santi]

What kind of change does this PR introduce?

Improves typing definitions enough for mypy with a weak rule set to accept them. This is mostly an initial patch set to ease reviewing, as there are many things to improve still - mainly, remove Any usage in favor of generics, and improve the types of payloads with actual pydantic-based validation, with the ultimate goal of making the code type check with strict = true.

It also adds a new step to enforce mypy ./realtime in CI from now on.

What is the current behavior?

No type checking at all.

What is the new behavior?

$ mypy ./realtime
Success: no issues found in 17 source files

Additional context

This should contain no breaking changes, just some rewiring of internal plumbing. The only real change I made is removing the AsyncRealtimeClient.summary method, which was broken as it used a non existant channel.listeners property.

[Copilot]

Pull Request Overview

Improves type safety by refining typing definitions across the realtime module and integrates MyPy into CI.

• Updated typing annotations (e.g., Mapping, TypedDict, callback generics) and reduced Any usage.
• Converted Message to a Pydantic BaseModel and removed the broken summary method.
• Added MyPy configuration and CI steps for automated type checking.

Reviewed Changes

Copilot reviewed 9 out of 10 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
realtime/types.py	Refined enum type hint, updated callback and TypedDict definitions
realtime/message.py	Switched Message to Pydantic BaseModel and adjusted payload type
realtime/exceptions.py	Broadened error message parameter type
realtime/_async/push.py	Switched to Pydantic Message, updated payload types and hook logic
realtime/_async/presence.py	Replaced callback dict with individual attributes and updated hook flows
realtime/_async/client.py	Fixed send/receive for Message, updated connection typing and logging
realtime/_async/channel.py	Updated callback signatures, replaced raw dicts with Message, removed summary
pyproject.toml	Added pydantic dependency and MyPy settings
.github/workflows/ci.yml	Added MyPy type-check steps using Poetry and Nix

Comments suppressed due to low confidence (3)

realtime/_async/channel.py:318

• [nitpick] Parameter type shadows the built-in type and filter shadows the built-in filter. Consider renaming to more descriptive names like event_type and filter_args to improve readability and avoid confusion.

    def _on(

.github/workflows/ci.yml:39

• [nitpick] There are duplicate Type check steps in the CI workflow (one using Poetry and one using Nix). Consider consolidating them or giving each a distinct name to clarify their purpose.

      - name: Type check

realtime/_async/channel.py:265

• Changed the payload for the phx_close event from the original "leave" string to an empty dict, which may break consumers expecting a termination reason. Consider restoring the original payload or updating callers accordingly.

            self._trigger(ChannelEvents.close, {})

[Copilot]

Removal of the __hash__ method makes Message instances unhashable; if these objects need to be used in sets or dict keys, consider reintroducing a custom __hash__ implementation or documenting this change.

[coveralls]

Pull Request Test Coverage Report for Build 16199329439

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 110 unchanged lines in 6 files lost coverage.
• Overall coverage decreased (-0.01%) to 81.078%

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Files with Coverage Reduction	New Missed Lines	%
types.py	1	98.91%
exceptions.py	2	63.64%
_async/push.py	12	85.37%
_async/presence.py	18	80.37%
_async/client.py	29	74.21%
_async/channel.py	48	75.11%

Totals
Change from base Build 16148084255:	-0.01%
Covered Lines:	647
Relevant Lines:	798

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💛 - Coveralls