⚠️ WARNING: Please notice that part of this functionality (latency alerts) should not be shown anymore as per the following PR: #129597. Make sure to test the requirements in that PR instead of this one.

Summary

This PR addresses the Synthetics Service issue about network bandwidth limits. I can't link it here as it's on a non-public repo.

It does so by adding warnings for when the user exceeds throttling limits, or does not enable throttling when assigning monitors to a location.

How to test this PR Locally

1. Create a new manifest.json with the following content and place it under a folder named, for example, manifest_folder.

   {
     "throttling": {
       "downloadBandwidthLimit": 20,
       "uploadBandwidthLimit": 10,
       "latencyLimit": 5000
     },
     "locations": {
       "Local Synth Node [MANIFEST]": {
         "url": "https://localhost:10001",
         "geo": {
           "name": "Example - Local",
           "location": {"lat": 41.25, "lon": -95.86}
         },
         "status": "beta"
       }
     }
   }

2. Run an HTTP server to serve the contents of the manifest_folder

   $ npx http-server manifest_folder --port 8082
   

3. In Kibana's config, fill the following options:

   # Make sure your pods will be able to send data to ES which should be bound to your host's 9200 port
   xpack.uptime.service.hosts: [http://host.docker.internal:9200]
   
   # Add the URL for the manifest with the `throttling` configs you're serving
   xpack.uptime.service.manifestUrl: http://localhost:8082/manifest.json
   
   # Make sure to disable the devUrl so you're only fetching locations from the `manifest` as we'll do in production
   # xpack.uptime.service.devUrl: https://localhost:10001
   
   # Enable the Monitor Management UI
   xpack.uptime.ui.monitorManagement.enabled: true

4. Run the service locally

   $ DEV=true LOGLEVEL=trace CACERTFILE=./k8s/cert-test/build/bundle.pem SERVERCERT=./k8s/cert-test/build/local-server.pem SERVERKEYFILE=./k8s/cert-test/build/local-server.key PORT=10001 ./synthetics-service
   

5. Run Kibana and try to add a monitor. You should see the warnings above when exceeding the limits defined in your manifest.json file.
6. Disable throttling and you should see a warning about the automatic caps.
7. Create a monitor with a particular throttling value set and save it. Use the following code for that monitor:

   step("load homepage", async () => {
       await page.goto('https://www.fast.com');
   });
   
   step("wait for test", async () => {
     await page.waitForSelector('#show-more-details-link');
     await page.waitForTimeout(10000);
     await page.click("#show-more-details-link");
   });
   
   step("wait for up/lat", async () => {
     await page.waitForSelector(".extra-measurement-value-container.succeeded");
     await page.waitForTimeout(10000);
   });

8. Wait for that monitor to run and ensure your throttling values have been applied.
9. Create a monitor with throttling disabled using the same script as above and confirm that your script has not been throtted.
   ⚠️ It will be throttled on the service because of platform limits.
10. Create a monitor with throttling values which exceed the limits for the node. You should still be able to save such monitors.

Checklist

Delete any items that are not applicable to this PR.

• Any text added follows EUI's writing guidelines, uses sentence case text and includes i18n support
• Documentation was added for features that require explanation or tutorials -> Do we need this now or should we wait until we're out of beta?
• Unit or functional tests were updated or added to match the most common scenarios
• Any UI touched in this PR is usable by keyboard only (learn more about keyboard accessibility)
• Any UI touched in this PR does not create any new axe failures (run axe in browser: FF, Chrome)
• If a plugin configuration key changed, check if it needs to be allowlisted in the cloud and added to the docker list
• This renders correctly on smaller devices using a responsive layout. (You can test this in your browser)
• This was checked for cross-browser compatibility

For maintainers

• This was checked for breaking API changes and was labeled appropriately

Release note

Show warning when users exceed a Synthetics Node throttling limits.