Sample Application with Go and Gin

This sample is running on: https://go-gin.is-easy-on-scalingo.com/

Deploy via Git

Create an application on https://scalingo.com, then:

scalingo --app my-app git-setup
git push scalingo master

And that's it!

Deploy via One-Click

Running Locally

docker-compose up

The app listens by default on the port 3000 or the one defined in the PORT environment variable.

DNS Debug Cron

This project now uses the official Scalingo Scheduler with a cron.json file at the repository root:

{
  "jobs": [
    {
      "command": "*/10 * * * * /bin/bash ./scripts/debug_dns_allowlist.sh"
    }
  ]
}

The schedule respects the Scalingo Scheduler limitation documented by Scalingo: the minimum interval is 10 minutes, and schedules are evaluated in UTC.

The job executed by the scheduler only probes domains you explicitly provide. It logs:

• /etc/resolv.conf
• Scalingo runtime context such as APP, CONTAINER, HOSTNAME, SCALINGO_PRIVATE_HOSTNAME, SCALINGO_PRIVATE_NETWORK_ID, and REGION_NAME
• dig output when available
• getent ahosts output when available
• nslookup output when available

Available environment variables:

SCALINGO_APP=test-secnum
DNS_DEBUG_ALLOWLIST_FILE=./dns-allowlist.txt
DNS_DEBUG_CLI_TABLE_FILE=./private-networks-domain-names.txt
DNS_DEBUG_DOMAINS=db.internal.example,redis.internal.example

Local test:

cp dns-allowlist.txt.example dns-allowlist.txt
./scripts/debug_dns_allowlist.sh

You can also inject the domains directly through an environment variable:

DNS_DEBUG_DOMAINS="db.internal.example redis.internal.example" ./scripts/debug_dns_allowlist.sh

Or paste the output of scalingo -a test-secnum private-networks-domain-names into private-networks-domain-names.txt; the script extracts the DOMAIN NAME column automatically:

cp private-networks-domain-names.txt.example private-networks-domain-names.txt
./scripts/debug_dns_allowlist.sh

Trigger Scalingo Deployments In A Loop

The repository also includes a helper script that waits a random amount of time, then triggers a real manual deployment through the Scalingo CLI:

chmod +x scripts/simulate_scalingo_deployments.sh
DEPLOY_BRANCH=main MIN_WAIT_SECONDS=30 MAX_WAIT_SECONDS=180 ./scripts/simulate_scalingo_deployments.sh test-secnum

By default the loop runs forever. Set DEPLOY_COUNT if you want a fixed number of deployments:

DEPLOY_BRANCH=main DEPLOY_COUNT=5 MIN_WAIT_SECONDS=10 MAX_WAIT_SECONDS=30 ./scripts/simulate_scalingo_deployments.sh test-secnum

If you want the CLI to follow deployment logs, enable FOLLOW_DEPLOY=true:

DEPLOY_BRANCH=main FOLLOW_DEPLOY=true ./scripts/simulate_scalingo_deployments.sh test-secnum