fix: partial write error handling

[NguyenHoangSon96]

Closes #

Proposed Changes

The current exception classes hierarchy are InfluxDBError -> InfluxDBPartialWriteError and ApiException

• In InfluxDBError there is an important function _get_message(self, response) , this function will run everytime a subclass of InfluxDBError is initialized, inside this function there is a quite heavy function will run, that is _parse_partial_write_line_error_info(data), so when a partial write error occurs _get_message(self, response) will be called at least twice.
  Some issues:
• With the current implementation it is quite hard to make exception classes run efficiently when a partial writes error occurs.
• Exception class should not have any logic that can affect other exceptions. Exception classes should just some simple data carrier objects with very limited functionality as mine knowledge, or at least this is what I have seen on other v3 clients.
• json.loads(response.data) was called multiple times like in Java v3.
• The assumption that every subclass of InfluxDBError will have the same way of parsing the error messages like we do in _get_message(self, response) function is not correct... I think.
  We can try to make everything work more efficiently as possible with the current exception classes implementation, but I still feel It very wrong on the architecture and design perspective.
• InfluxDBPartialWriteLineException changed to InfluxDBPartialWriteExceptionLine

What I'm trying to do right now is moving all logic inside exception classes to WriteApi class (or wherever than inside exception classes) and making them as lightweight as possible. They should only carry information about the errors;

Checklist

• CHANGELOG.md updated
• Rebased/mergeable
• A test has been added if appropriate
• Tests pass
• Commit messages are conventional
• Sign CLA (if not already signed)

[Copilot]

Pull request overview

This PR refactors write error handling to better distinguish partial-write errors from generic write failures by parsing JSON error bodies and conditionally raising InfluxDBPartialWriteError only when accept_partial is enabled and the response matches the expected “rejected rows” list format.

Changes:

• Update write exception translation to parse JSON bodies and format per-line rejection details for partial writes.
• Adjust sync REST client response decoding to normalize empty bodies to None.
• Expand and update tests to cover partial-write detection, message formatting, and fallback behaviors.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
tests/test_write_api.py	Adds broader unit coverage for write-error classification and fallback messaging; updates existing error-translation tests.
tests/test_influxdb_client_3_integration.py	Loosens assertion on v3 error message content and narrows the tested accept_partial configuration.
influxdb_client_3/write_client/client/write_api.py	Implements new JSON parsing and partial-write detection/formatting in _translate_write_exception.
influxdb_client_3/write_client/_sync/rest_client.py	Avoids decoding empty bodies and normalizes empty data to None.
influxdb_client_3/exceptions/exceptions.py	Changes exception message handling and updates partial-write error types/constructors.

Suppressed comments (1)

influxdb_client_3/exceptions/exceptions.py:69

• These PEP 604 union annotations (int | None, etc.) will fail to parse on Python <3.10. Use Optional[...] (with Optional imported from typing) to preserve compatibility.

class InfluxDBPartialWriteLineError:
    line_number: int | None
    error_message: str | None
    original_line: str | None

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[Copilot]

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.

Suppressed comments (2)

influxdb_client_3/exceptions/exceptions.py:5

• Python 3.9 is still in the CI matrix, but this module now uses PEP 604 union syntax elsewhere (int | None), so you’ll need Optional available for 3.9-compatible type annotations.

from typing import List

influxdb_client_3/exceptions/exceptions.py:69

• int | None / str | None type syntax is a Python 3.10+ feature and will raise a SyntaxError on Python 3.9 (which is still in .github/workflows/pylint.yml). Use Optional[...] instead for compatibility.

class InfluxDBPartialWriteLineError:
    line_number: int | None
    error_message: str | None
    original_line: str | None

[codecov]

Codecov Report

❌ Patch coverage is 94.52736% with 11 lines in your changes missing coverage. Please review.
✅ Project coverage is 87.99%. Comparing base (7ceb8bf) to head (786a0d7).

Files with missing lines	Patch %	Lines
...luxdb_client_3/write_client/client/util/helpers.py	0.00%	5 Missing ⚠️
influxdb_client_3/exceptions/write_exceptions.py	97.14%	4 Missing ⚠️
influxdb_client_3/__init__.py	80.00%	1 Missing ⚠️
...nfluxdb_client_3/write_client/_sync/rest_client.py	83.33%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #239      +/-   ##
==========================================
+ Coverage   87.78%   87.99%   +0.20%     
==========================================
  Files          28       28              
  Lines        2072     2049      -23     
==========================================
- Hits         1819     1803      -16     
+ Misses        253      246       -7     

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[bednar]

I found five issues that need to be addressed before approval.

[NguyenHoangSon96]

@karel-rehor
This PR is now ready to be reviewed.
Please check when you have time.

[karel-rehor]

I have some concerns about missed opportunities to improve and simplify the API. This is of course open for discussion.

[Copilot]

🟡 Changes recommended

Critical import and exception-hierarchy issues remain, along with additional error-handling and compatibility findings.

9 open findings

• Fix undefined InfluxDB query exception import · New
• Import write_exceptions from the exceptions package · New
• Make partial-write exceptions inherit from write exceptions · New
• Fix invalid exception import and constructor arguments · New
• Lint job no longer covers all supported Python versions · New
• Require line error messages to be non-empty strings · New
• Preserve the response in fallback exceptions · New
• Use accepts instead of except in changelog entry · New
• Correct write_exceptions module path in docstring example · New

3 resolved since last review

• _is_partial_write_error currently treats any data: [] as a partial-write error when…
• InfluxDBError(response=...) now sets self.message to the passed message even when it’s…
• InfluxDBError.__init__ sets self.message = message when a response is provided. Existing…

🧠 Review effort: Lite

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[NguyenHoangSon96]

Hi Karel, do you agree with this suggestion?

[NguyenHoangSon96]

Hi @karel-rehor
You can resume your review now.
Exception classes have been refactored. These exception classes refactor are the latest commit.
Some work still needs to be done like add code comments and update to CHANGELOG.md, … but I think you should check a "first round" first.

[karel-rehor]

So far the refactoring looks great.

I still have a suggestion for revising the name of the InfluxDBPartialWriteLineException class, which seems to be inaccurately named.

It involves a bit of linguistic jargon, but linguistics has long been a bit of a hobby.

[karel-rehor]

After seeing similar classes to this in other libraries, it now occurs to me why the name seems odd.

Lexicologically in English most often all modifying adjectival seme (A) precede the seme indicating the substative nucleus (N) of the phrase, which indicates its wider contextual semantic role. e.g. "Big (A) blue (A) french (A) poodle (N)". Wider contextual semantic roles: "A big blue french poodle ate my Siamese cat." or "My girlfriend ran over a big blue french poodle." In either case the nucleus "poodle" occurs last.

The name InfluxDBParialWriteLineException, with the seme "Exception" occurring last, implies that the substantive nucleus of the class and the objects from which it is derived will assume the semantic role of an exception. e.g. "Influx(A) DB(A) Partial(A) Write (A) Line (A) Exception (N)". In other words it implies that it will encapsulate exceptions occurring from a Line.

But I believe the role of this class is more to encapsulate a complex line of information derived from an exception and not to be an exception.

So a more accurate name would need the seme for the nucleus to be "Line" and for this to be in the last place, which would probably best be "Influx(A) DB(A) Partial(AV) Write(A) Exception(A) Line(N)" or InfluxDBPartialWriteExceptionLine.

Perhaps this is may seem trivial at this phase. But I think it makes the intention behind the code clearer.

I'm unsure of the how word order works in Vietnamese (the current order may be a transfer of lexical rules), but in Czech it is perfectly possible to have an order like (A)-(N)-(A). Still in English, which implies programming languages derived from English, the order of words or of seme must be more strictly observed.

We may want to review this in other updated libraries.

[NguyenHoangSon96]

No, I have no problem with that.
I changed the class name to InfluxDBPartialWriteExceptionLine.