Push rejected, failed to compile Go app. Error when deploying Go to Heroku

About the error

I wanted to deploy the API made with Go to Heroku, git push heroku main I gave a command

!     Push rejected, failed to compile Go app.
!     Push failed

Failed with the above error.

The solution

Looking back at the log,

-----> 
 !!    The go.mod file for this project does not specify a Go version
 !!    
 !!    Defaulting to go1.12.17
 !!    
 !!    For more details see: https://devcenter.heroku.com/articles/go-apps-with-modules#build-configuration
 !!    
-----> New Go Version, clearing old cache

There was a description like. At first I didn't think this was the cause, so I left it alone, but I decided to give it a try.

If you look it up, you can use go.mod to specify the go version on Heroku.

go.mod

module xxxx

// +heroku goVersion go1.15      <--add to
go 1.15

It seems that it needs to be described as. After rewriting and pushing again, I was able to deploy successfully.