Consolidate and harden NI-TLS create_grpc_channel error descriptions

[alexdubois-ni]

What does this Pull Request accomplish?

Consolidate and harden NI-TLS create_grpc_channel error descriptions

Why should this Pull Request be merged?

As of today, I added quite a bit of fud and inactionable user information to our error descriptions. Furthermore, there is a lot of error scenario detection logic surrounding this as well that can be simplified by using a consolidated error messaging. In the end, the ONLY actionable user scenario is that a TLS configuration error occurred and that they need to check Hardware Manager that they did setup correctly. We should reflect this in the error description.

Last but not least, let's also create a base error class that user's of nitlsconfig can utilize to catch all error types from nitlsconfig and inherit from that separately between the Cli related errors and grpc_channel configuration related errors. This way, user's have a more flexible and streamlined error handling capabilities. Make minor improvements to the cli errors to ensure they all inherit from this base.

Lastly, also make an improvement to one of the most prominent errors which is: What to do when nitlsconfig is not even installed!

Note: We do not care about backwards compatibility yet since this package is not truly "released" yet in any form. It is all in alpha development.

What testing has been done?

Updated unit-tests accordingly.

[ni-github-admins]

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[Copilot]

Pull request overview

Consolidates NI-TLS channel errors and introduces a shared package exception hierarchy.

Changes:

• Adds common CLI and TLS exception base classes.
• Simplifies TLS validation and standardizes error guidance.
• Updates server-mode tests for fail-closed behavior.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/nitlsconfig/errors.py	Defines the exception hierarchy.
src/nitlsconfig/cli.py	Imports centralized CLI exceptions.
src/nitlsconfig/grpc_channel.py	Consolidates TLS validation and messages.
src/nitlsconfig/__init__.py	Exports the new exception API.
tests/unit/test_grpc_channel.py	Updates TLS mode and validation tests.

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[github-actions]

Test Results

 12 files  ± 0   12 suites  ±0   15s ⏱️ ±0s
 66 tests  -  2   66 ✅  -  2  0 💤 ±0  0 ❌ ±0 
792 runs   - 24  792 ✅  - 24  0 💤 ±0  0 ❌ ±0 

Results for commit a7db719. ± Comparison against base commit 6baa5fb.

This pull request removes 6 and adds 4 tests. Note that renamed tests count towards both.

tests.unit.test_grpc_channel ‑ test_invalid_configuration_raises[empty_certificate_path]
tests.unit.test_grpc_channel ‑ test_invalid_configuration_raises[non_file_certificate_scheme]
tests.unit.test_grpc_channel ‑ test_invalid_configuration_raises[trust_always_unsupported]
tests.unit.test_grpc_channel ‑ test_invalid_configuration_raises[unknown_server_mode]
tests.unit.test_grpc_channel ‑ test_invalid_configuration_raises[unknown_trust_scheme]
tests.unit.test_grpc_channel ‑ test_skip_hostname_validation_matches_trusted_certificates

tests.unit.test_grpc_channel ‑ test_non_disabled_server_modes_match_trusted_certificates[SkipHostnameValidation]
tests.unit.test_grpc_channel ‑ test_non_disabled_server_modes_match_trusted_certificates[TrustAlways]
tests.unit.test_grpc_channel ‑ test_non_disabled_server_modes_match_trusted_certificates[Unknown]
tests.unit.test_nitlsconfig ‑ test_command_timeout_is_reported_as_a_package_error

♻️ This comment has been updated with latest results.

[Copilot]

Pull request overview

Copilot reviewed 7 out of 7 changed files in this pull request and generated no new comments.