Azure Self hosted agent to run pytest

问题

I have installed a self-hosted agent on my local VM, it's connected to azure no issues there. I have a python code on azure DevOps I have installed all the requirements.txt requirements manually into the cmd line of the local VM so that self-hosted agent installed on it doesn't have to install them ( to minimize the build & deployment time)

But when I have below code in the YAML file to run pytest cases pipeline is failing because of below error

This is my Yaml file

    trigger:
        - master
        variables:
          python.version : 3.8.6

        stages:
        - stage: Build
          jobs: 
          - job: Build
            pool:
              name: 'MaitQA'
            #pool:
            #  vmImage: 'windows-latest'   # windows-latest Or windows-2019 ; vs2017-win2016 # https://docs.microsoft.com/en-us/azure/devops/pipelines/agents/hosted?view=azure-devops&tabs=yaml#software # vs2017-win2016

            steps:
              - task: UsePythonVersion@0
                inputs:
                  versionSpec: '$(python.version)'
                displayName: 'Use Python $(python.version)'
                

        - script: 'pip install pytest pytest-azurepipelines ; pytest unit_test/'
                

This is The error --------------- Starting: Use Python 3.8.6 ------------------------------ Task : Use Python version Description : Use the specified version of Python from the tool cache, optionally adding it to the PATH Version : 0.151.4 Author : Microsoft Corporation Help : https://docs.microsoft.com/azure/devops/pipelines/tasks/tool/use-python-version ------------------------------------------- [error]Version spec 3.8.6 for architecture x64 did not match any version in Agent.ToolsDirectory. Versions in C:\CodeVersions_tool: If this is a Microsoft-hosted agent, check that this image supports side-by-side versions of Python at https://aka.ms/hosted-agent-software. If this is a self-hosted agent, see how to configure side-by-side Python versions at https://go.microsoft.com/fwlink/?linkid=871498. Finishing: Use Python 3.8.6 ---------------

回答1:

Did you follow How can I configure a self-hosted agent to use this task?

The desired Python version will have to be added to the tool cache on the self-hosted agent in order for the task to use it. Normally the tool cache is located under the _work/_tool directory of the agent or the path can be overridden by the environment variable AGENT_TOOLSDIRECTORY. Under that directory, create the following directory structure based off of your Python version:

回答2:

Including @Krzysztof Madej's suggestion, you can also try to restart the self-hosted agent service.

回答3:

This error refers to Python not being in the agent tools directory, and therefore unavailable to the agent.

Here are (incomplete) details for setting up the tools directory with Python:

https://docs.microsoft.com/en-us/azure/devops/pipelines/tasks/tool/use-python-version?view=azure-devops#how-can-i-configure-a-self-hosted-agent-to-use-this-task

The mystery in the above documentation is, what are those 'tool_files' they refer to?

Thankfully, jrm346 on GitHub went through the source code to work it out; for Linux you need to compile Python from source and reconfigure the target directory:

https://github.com/microsoft/azure-pipelines-tasks/issues/10721

For Python 3.8:

1. Create the needed file structure under the agent's tool's directory:

   Python

    └── 3.8.0
        ├── x64
        └── x64.complete
   

Then compile Python 3.8.6 following the below instructions, with one small addition: just after '/configure --enable-optimizations' of step 4 run the command './configure --prefix=/home/azure/_work/_tool/Python/3.8.0/x64', replacing '/home/azure/_work/_tool' with your agent's tools directory location:

https://linuxize.com/post/how-to-install-python-3-8-on-ubuntu-18-04/

来源：https://stackoverflow.com/questions/64212888/azure-self-hosted-agent-to-run-pytest