I wanted to run some tasks once a day. The idea being we run application to check from any drift/changes to configuration etc. Luckily this is simple in Azure devops.

We create a YAML pipeline with no trigger and create a cronjob style schedule instead as below

trigger: none

schedules:
- cron: "0 7 * * *"
  displayName: Daily
  branches:
    include:
    - main
  always: true

pool:
  vmImage: 'ubuntu-latest'

steps:
- task: UseDotNet@2
  inputs:
    packageType: 'sdk'
    version: '10.x'

- script: dotnet build ./tools/TestDrift/TestDrift.csproj -c Release
  displayName: Test for drift

- script: |
    dotnet ./tools/TestDrift/bin/Release/net10.0/TestDrift.dll
  displayName: Run Test for drift

- task: PublishTestResults@1
  inputs:
    testResultsFormat: 'JUnit'
    testResultsFiles: ./tools/TestDrift/bin/Release/net10.0/drift-results.xml
    failTaskOnFailedTests: true

In this example we’re publishing test results. Azure devops supports several formats, see the testResultsFormat variable. We’re just creating an XML file named drift-results.xml with the following format

<testsuite tests="0" failures="0">
  <testcase name="check site" />
  <testcase name="check pipeline">
    <failure message="pipeline check failed" />
  </testcase>
</testsuite>

In C# we’d do something like

var suite = new XElement("testsuite");
var total = GetTotalTests();
var failures = 0;

var testCase = new XElement("testcase",
   new XAttribute("name", "check pipeline")
);

// run some test
var success = RunSomeTest();

if(!success)
{
  failures++;
  testCase.Add(new XElement("failure",
    new XAttribute("message", "Some test name")
  ));
}

suite.Add(testCase);

// completed
suite.SetAttributeValue("tests", total);
suite.SetAttributeValue("failures", failures);

var exeDir = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location)!;
var outputPath = Path.Combine(exeDir, "tls-results.xml");

File.WriteAllText(outputPath, suite.ToString());

Using one of the valid formats, such as the JUnit format, will also result in Azure pipeline build showing a Test tab with our test results listed.