backoff 2.0.x update blocked by opentelemetry-exporter-otlp

[jvtm]

Describe your environment

• Python 3.8.12, 3.9.12, 3.10.4 (matrix build)
• Poetry 1.1.13
• Private package X depends on
  • backoff
  • opentelemetry-api
  • opentelemetry-sdk
  • opentelemetry-exporter-otlp
• Renovate bot trying to apply the backoff major version update from 1.x series to 2.0.x
• Other additional dependencies already updated to backoff 2.0.x series, resulting in failing builds and deployments

Steps to reproduce

1. Create pyproject.toml:

[tool.poetry]
name = "boffdep"
version = "1.0.0"
description = "backoff 2.x vs opentelemetry"
authors = []

[tool.poetry.dependencies]
python = "^3.10"
backoff = "^2.0.0"
opentelemetry-api = "^1.11.0"
opentelemetry-sdk = "^1.11.0"
opentelemetry-exporter-otlp = "^1.11.0"

[build-system]
requires = ["poetry_core>=1.0.0"]
build-backend = "poetry.core.masonry.api"

2. Run poetry install

What is the expected behavior?

Updating to / using backoff 2.0.x succeeds.

What is the actual behavior?

Poetry output:

Resolving dependencies...

  SolverProblemError

  Because no versions of opentelemetry-exporter-otlp match >1.11.0,<1.11.1 || >1.11.1,<2.0.0
   and opentelemetry-exporter-otlp (1.11.0) depends on opentelemetry-exporter-otlp-proto-http (1.11.0), opentelemetry-exporter-otlp (>=1.11.0,<1.11.1 || >1.11.1,<2.0.0) requires opentelemetry-exporter-otlp-proto-http (1.11.0).
  And because opentelemetry-exporter-otlp-proto-http (1.11.0) depends on backoff (>=1.10.0,<2.0.0), opentelemetry-exporter-otlp (>=1.11.0,<1.11.1 || >1.11.1,<2.0.0) requires backoff (>=1.10.0,<2.0.0).
  And because opentelemetry-exporter-otlp (1.11.1) depends on opentelemetry-exporter-otlp-proto-http (1.11.1)
   and opentelemetry-exporter-otlp-proto-http (1.11.1) depends on backoff (>=1.10.0,<2.0.0), opentelemetry-exporter-otlp (>=1.11.0,<2.0.0) requires backoff (>=1.10.0,<2.0.0).
  So, because boffdep depends on both backoff (^2.0.0) and opentelemetry-exporter-otlp (^1.11.0), version solving failed.

Additional context

Backoff 2.0.x release dropped Python 3.6 support.
https://github.com/litl/backoff/blob/master/CHANGELOG.md#v200---2022-04-26

Some Opentelemery Python components depend on backoff >= 1.10.0, < 2.0.0.

Previous change:
b2e9387

README states:

We remove support for old Python versions 6 months after they reach their end of life.
https://github.com/open-telemetry/opentelemetry-python#python-version-support-addition-and-removal

Python 3.6 reached EOL 2021-12-23, which means opentelemetry-python support for it ends in about five weeks from now.

-> Just wait? Or could the dependency be loosened (for fresh Python versions)?

[srikanthccv]

If there are no breaking changes with backoff 2.0 and it works with all environments, we can loosed the dependency earlier.

[jvtm]

If there are no breaking changes with backoff 2.0 and it works with all environments, we can loosed the dependency earlier.

According to backoff changelog it's just:

• dropping Python 3.6 support
• adding Python 3.10 support
• improving type hints

https://github.com/litl/backoff/blob/master/CHANGELOG.md

[srikanthccv]

Does it work with python3.6?

[musicinmybrain]

Does it work with python3.6?

They intentionally dropped Python 3.6 support in 2.0, although there might not be any actual incompatible changes.

If you still need to support Python 3.6 (which, as you probably know, is at end-of-life), you could still remove the upper bound on backoff for later Pythons, something like:

[options]
python_requires = >=3.6
install_requires =
    backoff >= 1.10.0, < 2.0.0; python_version<'3.7'
    backoff >= 1.10.0; python_version>='3.7'