pglite for testing - memory consumption issues?

[grmkris]

I love idea of using pglite for testing, since i can configure my app to run without any running dependencies. I just init pglite in memory instead of docker pg instance which simplifies my cicd, local run etc etc

buut i'm hitting some issues, my app is pretty large monolith with ~30 test files and each file has ~10 tests..

initally i was naively creating a pglite for each test (beforeEach) but this destroyed my ram... then i moved to a model where i create one pglite, run migration and prepare some inital data and save that as "golden instance" then for each test run i do pglite.clone() to get a clone version..
this still kills my computer in terms of memory, so next optimization would be to use the same pglite for each test inside a test file... but this breaks the logic where each test does not affect the test before or after it...

what are your tips for using pglite in cicd for large test codebases? maybe some examples from the wild ?

[SimonJTurner]

Hi +1 here because I'm currently working on this.

• I tried using pglite-tools/dump but it did not write the users/roles that I needed with the DB as well
• I tried using clone but it does not preserve the extensions
• I might be able to use dumpDataDir

Update:
Since clone is just a wrap on dumpDataDir and create, we should allow for some optional params.

async clone(): Promise<PGliteInterface> {
    const dump = await this.dumpDataDir('none')
    return PGlite.create({ loadDataDir: dump })
  }

[grmkris]

freshPgLite = await PGlite.create({
      loadDataDir: goldenDataDirDump,
      extensions: {
        uuid_ossp,
      },
    });

this starts taking 5+sec in 200+ test system where each test loads their own clean pglite instance