daemon-pinger

Simple Google Cloud Function to ping TurtleCoin daemons for their /info

Once deployed simply POST a JSON blob at the function's URL like so

curl -X POST \
  https://asia-east2-projectid.cloudfunctions.net/getInfo \
  -H 'Content-Type: application/json' \
  -d '{"url": "https://blockapi.turtlepay.io:"}'

The script will add /info to the end so don't specify that.

Two extra helpful items will also be added to the response blob

{
    "pingerInfo": {
        "gcpRegion": "asia-east2",
        "time": 76
    }
}

time is how long the request took in ms. Provided the ENV variable FUNCTION_REGION is set will give the gcpRegion where the function was run from:

• node.js 8 runtime sets this automatically
• node.js 10 runtime doesn't set this, needs to be done when deploying

The script is set to timeout after 4 seconds, so if daemon is down the longest the script will run is 4 seconds. It can run longer in certain circumstances so best to limit the script runtime via the --timeout param when deploying

Deploying

Using the Google Cloud SDK can issue this one liner to deploy it. Make sure you've done a gcloud init, setup prompts to do that.

gcloud functions deploy getInfo --runtime nodejs10 --trigger-http --memory=128M --timeout 5 --region=us-east4 --set-env-vars=FUNCTION_REGION=us-east4 --max-instances=5 --entry-point=getInfo

Can also deploy via the web console.

These are the regions currently available

• europe-west2 - England
• europe-west1 - Belgium
• us-east4 - Northern Virginia
• us-central1 - Iowa
• us-east1 - South Carolina
• asia-east2 - Hong Kong
• asia-northeast1 - Tokyo

License

Copyright 2019 Nicholas Orr. All Rights Reserved.
Use of this source code is governed by an MIT-style
license that can be found in the LICENSE file

Photo by Damon Lam on Unsplash