isabella232 / temporal-render-simple

temporal-render-simple

Simple Temporal Setup on Render

This is a template for running a simple version of Temporal on Render. This is not recommended for production beyond small use cases, as all 4 Temporal internal services (Frontend, Matching, History, and Worker) are being run out of one server, but the benefit is that setup is a lot simpler. For a more production-ready setup, see the render-examples/temporal repo.

The deployment also includes an example Go app that interacts with the cluster. Fork this repo and click the button below to try it out!

⚠️ Note: this blueprint spins up 4 server instances and 2 Postgres instances, all on Render's "Starter" plan, which (as of Feb 2022) will cost $42 if left running for a whole month. Remember to tear down your resources when just kicking the tires.

This repo defines a Render Blueprint with the following components:

• Temporal cluster:
  • Two Postgres databases, temporal-db and temporal-db-visibility.
  • A temporal server that runs all Temporal services.
  • temporal-ui provides the Temporal web UI.
• Example app (from Render's sample Temporal app):
  • app-workflow-trigger runs a simple HTTP server with two routes:
    • / for health checking.
    • /trigger-workflow for kicking off the TransferMoney workflow.
  • app-worker executes any triggered workflows.

Deploy Steps

1. Click the "Deploy to Render" button.

2. In your Render dashboard, click on the service app-workflow-trigger, and copy its URL. Let's say it's https://app-workflow-trigger.onrender.com/.

3. To verify that your Temporal cluster is running correctly, you can use Temporal's CLI tool tctl. Gain shell access to the temporal service:

   • Using SSH.
   • Using the web shell:

   Some commands to run (with expected, non-exact output):

   $ tctl cluster health
   temporal.api.workflowservice.v1.WorkflowService: SERVING
   $ tctl admin membership list_gossip  # list all temporal services.
   [
     {
       "role": "frontend",
       "member_count": 1,
       "members": [
         {
           "identity": "0.0.0.0:7233"
         }
       ]
     },
     {
       "role": "history",
       "member_count": 1,
       "members": [
         {
           "identity": "0.0.0.0:7234"
         }
       ]
     },
     {
       "role": "matching",
       "member_count": 1,
       "members": [
         {
           "identity": "0.0.0.0:7235"
         }
       ]
     },
     {
       "role": "worker",
       "member_count": 1,
       "members": [
         {
           "identity": "0.0.0.0:7239"
         }
       ]
     }
   ]

4. Go to https://app-workflow-trigger.onrender.com/. If everything is well, you will see "OK!".

5. Now trigger the example workflow by visiting https://app-workflow-trigger.onrender.com/trigger-workflow. It should print

   Transfer of $54.990002 from account 001-001 to account 002-002 is processing. ReferenceID: 5e1f48db-5021-4e05-adb6-8bca54587d40
   
   WorkflowID: transfer-money-workflow RunID: 3179d644-4235-4ea8-b1a4-b7c4fabb0afd
   

6. app-worker will immediately pick up and run this workflow. You can verify by clicking on the service, and going to the "Logs" tab:

7. To check that the workflow has been run successfully, click on the temporal-ui service, and go to its URL. Under the default namespace, you should find your workflow's run with the status "Completed".