Experimental/adding singlerun headless capabilty

[andrewbaxter439]

What

• This partially addresses concerns in Make main entry points and jar files consistent for clearer model use #177 in that it allows singlerun.jar to do a full run
• Adds the argument Run to cli to potentially allow run only (as opposed to setup only - tests for mutually exclusive argument conflicts)

Why

• Not a fully necessary step for users if Make main entry points and jar files consistent for clearer model use #177 refactoring is useful: if we wanted to do all gui-less runs consistently via a single class/method then this would be redundant
• However, it does allow for a potentially testable SimPathsStart full run, doing a headless replication of what the GUI does to make sure it works

Why it doesn't actually work

• Ideally, this should test and close testing once done. But SimPathsStart.main() currently cannot exit.
• So I've not yet aded the test
• engine.startSimulation() and never returns? Where should a return statement be added to find 'the end', but allow GUI runs to keep programme running?

Questions

• Worth having?
• If we run a singlerun.jar -g false -Run test, is this best done as a maven integration test or a github actions test @igelstorm?

[andrewbaxter439]

Edit

It works now! will do a full single run headlessly using singlerun.jar, adds a test to see if it works. Should be a mostly sufficient test of whether the GUI-based runs work, without starting the GUI itself.

[Copilot]

Pull Request Overview

This PR introduces headless single-run capability for singlerun.jar, allowing full simulation runs without the GUI and adds corresponding CLI flags and CI validation.

• Adjust default population size for quicker test runs
• Add doSetup/doRun flags with new Run CLI option and headless execution loop in SimPathsStart
• Extend GitHub Actions workflow to invoke a full setup-and-run of the headless jar

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 4 comments.

File	Description
src/main/java/simpaths/model/SimPathsModel.java	Updated default popSize from 170000 to 50000
src/main/java/simpaths/experiment/SimPathsStart.java	Introduced doSetup/doRun, new CLI options, headless loop, and conditional observer registration
.github/workflows/SimPathsBuild.yml	Added run-simpaths-start job to validate headless setup & run

Comments suppressed due to low confidence (3)

src/main/java/simpaths/experiment/SimPathsStart.java:51

• [nitpick] The flags doSetup and doRun are somewhat ambiguous; consider renaming to setupOnly/runOnly or similar to clearly express their intent.

private static boolean doSetup = true;

.github/workflows/SimPathsBuild.yml:61

• The workflow currently only verifies input files; consider adding checks for expected output artifacts (e.g., simulation results) to ensure the headless run completes successfully.

run: java -jar singlerun.jar -c UK -s 2019 -g false --rewrite-policy-schedule

src/main/java/simpaths/experiment/SimPathsStart.java:229

• Omitting the observer in headless mode may disable critical observation logic. Verify that removing the observer for non-GUI runs does not impact required data collection or reporting.

if (showGui) engine.addSimulationManager(observer);

[justin-ven]

Good to hear that you found a work-around