scorecard/cron/internal/emulator

Configuring a local environment to test the Scorecard Cron Job

This emulator focuses on being able to test the worker, which pulls messages from a pubsub, processes them, and writes the results to a Google Cloud Storage (GCS) bucket. It's necessary to support pubsub, gcs, and the controller to get the worker working.

In general, you'll need 4-5 terminals (or tmux) to run everything needed.

GCS emulator

fake-gcs-server meets our needs and is written in Go. We may be able to use it as a library for unit tests in the future.

For now, the binary is good enough, so install it from source (or Releases):

go install github.com/fsouza/fake-gcs-server@latest

Now you can run the fake from the root of the Scorecard repo in your first window:

fake-gcs-server -scheme http -public-host 0.0.0.0:4443 \
    -backend filesystem -filesystem-root cron/internal/emulator/fakegcs

pubsub emulator:

Google Cloud has a pubsub emulator with complete install instructions. I've summarized some of them below.

One time setup

gcloud components install pubsub-emulator
gcloud components update

Anywhere outside your scorecard repo:

git clone https://github.com/googleapis/python-pubsub
cd python-pubsub/samples/snippet
pip install -r requirements.txt

Running the pubsub emulator (needed to do every time)

In a second window from any directory, run the emulator itself:

export PUBSUB_PROJECT_ID=test
gcloud beta emulators pubsub start --project=$PUBSUB_PROJECT_ID

In a third window (from the samples/snippet directory wherever you cloned python-pubsub) create the topic and subscription:

export PUBSUB_PROJECT_ID=test
export TOPIC_ID=scorecard-batch-requests
export SUBSCRIPTION_ID=scorecard-batch-worker
$(gcloud beta emulators pubsub env-init)
python3 publisher.py $PUBSUB_PROJECT_ID create $TOPIC_ID
python3 subscriber.py $PUBSUB_PROJECT_ID create $TOPIC_ID $SUBSCRIPTION_ID
alias drain-pubsub="python3 subscriber.py $PUBSUB_PROJECT_ID receive $SUBSCRIPTION_ID"

At any point you can drain the queue by running the following in the same window. Make sure to stop the command when testing the worker:

drain-pubsub

run Scorecard cron components

Commands intended to be run from the base of the Scorecard repo. Since this is intended to be used during development, go run is used but there's no reason you can't use go build. The repos in cron/internal/emulator/projects.csv and the cron/internal/emulator/config.yaml file can be changed as needed.

controller

$(gcloud beta emulators pubsub env-init)
export STORAGE_EMULATOR_HOST=0.0.0.0:4443
go run $(ls cron/internal/controller/*.go | grep -v _test.go) \
    --config cron/internal/emulator/config.yaml \
    cron/internal/emulator/projects.csv

worker

$(gcloud beta emulators pubsub env-init)
export STORAGE_EMULATOR_HOST=0.0.0.0:4443
go run $(ls cron/internal/worker/*.go | grep -v _test.go) \
    --ignoreRuntimeErrors=true \
    --config cron/internal/emulator/config.yaml