🎉 Implement scheduled event for positive TempIDs list #27
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serverless.yml
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| @@ -42,6 +43,11 @@ functions: | |||
| path: /{proxy+} | |||
| method: any | |||
| cors: true | |||
| schedule-main: | |||
| handler: dist/schedule-main.handler | |||
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@shogo-mitomo
I can verify that this might not work, because I was trying to do something similar and ran into the same issue. 😢
I get the error:
[Nest] 29960 - 04/20/2020, 1:20:00 AM
[ExceptionHandler] The default Firebase app already exists.
This means you called initializeApp() more than once without providing an app name as the second argument.
In most cases you only need to call initializeApp() once.
But if you do want to initialize multiple apps,
pass a second argument to initializeApp() to give each app a unique name. +4ms
You can reproduce this error by:
- Let the cron function run successfully.
- Try to load any endpoint, ex:
http://localhost:3000/dev.
The app will crash.
I think it's happening because both the handlers try to create AppModule, which tries to re-create firebase instance each time for the lambda-main handler and schedule-main handler.
Hence this error message.
I'm further investigating right now how to handle this.
I guess easiest solution would be to split the handlers into mutliple serverless.yml files. This would mean the cron nest app will run in different AWS Lambda from main nest app.
This might actually be the behavior we want because we might not want to scale up our cron job as our main app scales up?. 🤔
| @@ -42,6 +43,12 @@ functions: | |||
| path: /{proxy+} | |||
| method: any | |||
| cors: true | |||
| schedule-main: | |||
| handler: dist/schedule-main.handler | |||
| reservedConcurrency: 1 | |||
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@shogo-mitomo for reservedConcurrency
Does this mean that even if there are 100 lambda instances running, only 1 instance will run this cron function? 😲
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@yashmurty
my understanding is:
Originally, lambda-main and schedule-main are separated as a Lambda Function, so they are invoked and scaled separately.
schedule-main function does not scale when many HTTP requests come in. This is because there is no http event defined for this function.
reservedConcurrency is a setting to prevent the next function from being invoked while the old function is running because it takes more time to process than the interval of Cron, for example.
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Originally, lambda-main and schedule-main are separated as a Lambda Function, so they are invoked and scaled separately.
Noted.
If that is the case, then you will not face the firebase issue of multiple initialization as well, because each function will run on separate lambda. 🙏
TODO
Closes #10