Migrated Workflows From In Memory to Db

[keremeyuboglu]

• There was a constant error with no table found error. See issue: bugs when use attach database mattn/go-sqlite3#511
  Had to make a change for dev environment since appearently in memory sqlite creates a new in memory db instance when creating a new connection. I haven't run into issues testing the web app and running the integrations tests but I think it's important to keep that in mind.

• Right now I'm polling the enabled workflows from database in 100ms intervals.

• Changing defer in GcSessions sped up the integration test by a second since it closed connection earlier(was getting errors in session, so had to tinker with it a lot.)

Some Additional Footnotes

• I had to relocate some non-db related workflow stuff to persistence/workflow.go. But I'd like them to be under services package but the only way is to create another struct that embeds the db model. Since I haven't seen something like that in the project I've left that as is. Although I've relocated background job related stuff to workflow.go, so that workflowService only have functions that serve the API.

For example in services/workflow.go:

type MyWorkflow struct {
	persistence.Workflow
}

func (workflow MyWorkflow) Call(params ...interface{}) (result interface{}, err error) {
	f := reflect.ValueOf(persistence.FUNC_MAP[workflow.FunctionName])
	if len(params) != f.Type().NumIn() {
		err = errors.New("the number of params is out of index")
		return
	}
	in := make([]reflect.Value, len(params))
	for k, param := range params {
		in[k] = reflect.ValueOf(param)
	}
	res := f.Call(in)
	result = res[0].Interface()
	return
}

Haven't made changes about this yet but when for example creating a workflow, we're returning a generic internal server error if there's no topic in database with that particular name. Shouldn't we specify messages a little bit, but to at what extend. Should I create an error saying that in service layer and catch and serve that error to the user or
Log that error but give a generic error message that it can't be created with bad request instead of server error?

[bdkiran]

Hi Kareem, I'm reviewing your changes and the question about where some of the methods should live.

[bdkiran]

Similar to how we did in sessions and stickyConnections let's explicitly close tho rows instead of leaving it up to defer

[keremeyuboglu]

I'm changing all row-related defer statements while I'm at it

[bdkiran]

Everything looks good to me here