| # Quest Agent |
| |
| The execution service for Chrome perf. |
| |
| - Owner: |
| - Mailing list: TBD |
| - [Design Doc](go/quest-agent-dd) |
| - Tracking Bug: TBD |
| - Status: **In Design** |
| |
| # Overview |
| |
|  |
| |
| ## QuestAgent Service |
| |
| The RPC service that executes a predefined quest / function, or queries an |
| ongoing quest. The service is wrapped inside RPC endpoints to isolate clients |
| from underlying storage schemas and Agent implementations details. This enjoys |
| all the benefits by hiding invocations behind RPC endpoints. |
| |
| ## QuestAgent Executor |
| |
| The demon-like service to execute the quests. It creates a topic, subscribes to |
| the pub/sub queue and continues to run. This should be able to be deployed to |
| Cloud Run or Cloud Function, or incorporated into any other long-running |
| service in Skia infra as well. |
| |
| One QuestExecutor is created to handle one quest type, one message queue/topic |
| is dedicated to one quest type. The executor is responsible for creating a |
| topic to indicate that it is ready to process quests. Multiple executors can be |
| started to handle requests in a distributed manner. |
| |
| ## Quest |
| |
| A Quest is a Go function that typically does followings: |
| |
| - Encapsulates all the logic that should not be too long or complicated |
| - Invokes remote services or quests synchronously (waiting on the result to |
| proceed) |
| - Runs a fairly complicated algorithm to process an input or an output from |
| other services |
| - Spawns another goroutine and waits on its completion |
| - Outputs results whose size should be relatively small |
| |
| However there are Go functions that may not be considered as a quest: |
| |
| - Continues to poll an external service |
| - Runs at a certain interval (cron jobs) |
| - Spawns another job but don't wait on its completion |
