feat: support partial writes

[alespour]

Proposed Changes

This PR adds partial-write support in the Python client and finalizes write API selection behavior for product compatibility.

Feature highlights:

• Adds structured partial-write errors via InfluxDBPartialWriteError with per-line details:
  • line_number
  • error_message
  • original_line
• accept_partial defaults to true (server default behavior)
• accept_partial=false is sent only when partial writes are explicitly disabled
• use_v2_api routes writes between:
  • V2 API endpoint: /api/v2/write
  • V3 API endpoint: /api/v3/write_lp

Default behavior and option semantics:

• Default writes use the V2 API endpoint (use_v2_api=true).
• no_sync requires use_v2_api=false and is rejected otherwise.
• accept_partial applies only to V3 endpoint writes and is not used on V2 endpoint writes.

Configuration surfaces:

• Write options: accept_partial, use_v2_api, no_sync
• Constructor kwargs: write_accept_partial, write_use_v2_api, write_no_sync
• Environment variables: INFLUX_WRITE_ACCEPT_PARTIAL, INFLUX_WRITE_USE_V2_API, INFLUX_WRITE_NO_SYNC

See Partial writes for reference.

Example (partial-write handling):

try:
    client.write(lp)
except InfluxDBPartialWriteError as e:
    for line_err in e.line_errors:
        print(f"line {line_err.line_number} failed: {line_err.error_message} ({line_err.original_line})")
except InfluxDBError as e:
    print(e.message)

Example (enable V3 write options):

client = InfluxDBClient3(
    host=host,
    token=token,
    database=database,
    write_use_v2_api=False,
    write_no_sync=True,
    write_accept_partial=False,
)

client.write(lp)

Checklist

• CHANGELOG.md updated
• Rebased/mergeable
• A test has been added if appropriate
• Tests pass
• Commit messages are conventional

[codecov]

Codecov Report

❌ Patch coverage is 99.04306% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 77.45%. Comparing base (f8a0805) to head (c3f5407).

Files with missing lines	Patch %	Lines
influxdb_client_3/__init__.py	95.83%	1 Missing ⚠️
influxdb_client_3/exceptions/exceptions.py	99.09%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #213      +/-   ##
==========================================
+ Coverage   76.05%   77.45%   +1.40%     
==========================================
  Files          37       37              
  Lines        2543     2710     +167     
==========================================
+ Hits         1934     2099     +165     
- Misses        609      611       +2     

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[Copilot]

Pull request overview

This PR adds partial-write support to the InfluxDB 3 Python client by introducing a structured partial-write exception and by finalizing write endpoint selection logic to support both the V2 compatibility endpoint (/api/v2/write) and the V3 LP endpoint (/api/v3/write_lp). It also exposes new write configuration surfaces (options, constructor kwargs, and env vars) and updates tests and documentation accordingly.

Changes:

• Introduces InfluxDBPartialWriteError / InfluxDBPartialWriteLineError and structured parsing/formatting of partial-write responses.
• Adds write routing and option semantics via use_v2_api, accept_partial, and no_sync (including validation and env/kwargs wiring).
• Updates unit/integration tests and README/CHANGELOG to cover and document the new behaviors.

Reviewed changes

Copilot reviewed 12 out of 12 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
influxdb_client_3/write_client/client/write_api.py	Adds default write options (accept_partial, use_v2_api), per-request option resolution, and validation before dispatch.
influxdb_client_3/write_client/service/write_service.py	Routes requests to /api/v2/write vs /api/v3/write_lp, adds partial-write error raising, and improves 405 compatibility errors.
influxdb_client_3/exceptions/exceptions.py	Adds partial-write detection/parsing helpers and the new structured partial-write exception types.
influxdb_client_3/exceptions/__init__.py	Exports the new partial-write exception types.
influxdb_client_3/__init__.py	Adds env vars + constructor kwargs for new write booleans and updates env parsing helper.
README.md	Documents partial-write handling and endpoint compatibility configuration.
CHANGELOG.md	Records the new feature and option semantics.
tests/test_api_client.py	Expands error parsing tests to assert structured partial-write errors and fallback behavior.
tests/test_influxdb_client_3.py	Updates default option assertions, env/kwargs boolean parsing tests, and adds async multi-precision list behavior test.
tests/test_influxdb_client_3_integration.py	Updates integration coverage to expect InfluxDBPartialWriteError on partial write failures.
tests/test_write_local_server.py	Adds/updates local-server routing tests for use_v2_api, accept_partial, and no_sync validation.
tests/test_polars.py	Updates mock expectations to include new write parameters.

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[Copilot]

Pull request overview

Copilot reviewed 12 out of 12 changed files in this pull request and generated 3 comments.

[Copilot]

Pull request overview

Copilot reviewed 12 out of 12 changed files in this pull request and generated 3 comments.

[Copilot]

Pull request overview

Copilot reviewed 12 out of 12 changed files in this pull request and generated 1 comment.

[dburton-influxdata]

Is this Partial Write logic being considered or has it been implemented in Telegraf?