Run cron in Golang while having different databases - mongodb

Question

I am working on a SaaS based project on which Merchants can subscribe to set up their online store.
Project Overview
I am using Golang (backend), Mongodb database service and Angular4 (frontend) to build the system. I have multiple merchants that can set up their store. Each merchant has its own url (having its business name as subdomain in the url) to connect to his database.
For Routing, I am using Golang's Gin framework at back end.
Problem
I want to run the cron jobs for the merchant-specific database. In these cron jobs there are some operations that need to connect to the database. But in my routing, until a route for an API is called, the database won't be set. And ultimately, the cron does not run with proper data.
Code
cron.go
package cron
import (
"gopkg.in/robfig/cron.v2"
"controllers"
)
func RunCron(){
c := cron.New()
c.AddFunc("#every 0h1m0s", controllers.ExpireProviderInvitation)
c.Start()
}
Controller function
func ExpireProviderInvitation() {
bookingAcceptTimeSetting, _ := models.GetMerchantSetting(bson.M{"section": "providers", "option_name": "bookings_accept_time"})
if bookingAcceptTimeSetting.OptionValue != nil{
allInvitations, _ := models.GetAllBookingInvitations(bson.M{ "status": 0, "send_type": "invitation", "datetime": bson.M{"$le": float64(time.Now().Unix()) - bookingAcceptTimeSetting.OptionValue.(float64)} })
if len(allInvitations) > 0 {
for _, invitationData := range allInvitations {
_ = GetNextAvailableProvider(invitationData.Bid, invitationData.Pid)
}
}
}
}
router.go
func NewRouter() {
router := gin.Default()
router.Use(gin.Recovery())
router.Use(SetMerchantDatabase)
public := router.Group("/api/v1")
for _, route := range publicRoutes{
switch route.Method {
case "GET" : public.GET(route.Pattern, route.HandlerFunc)
case "POST" : public.POST(route.Pattern, route.HandlerFunc)
case "PUT" : public.PUT(route.Pattern, route.HandlerFunc)
case "DELETE": public.DELETE(route.Pattern, route.HandlerFunc)
default : public.GET(route.Pattern, func(c *gin.Context){
c.JSON(200, gin.H{
"result": "Specify a valid http method with this route.",
})
})
}
}
router.NoRoute(controllers.UnauthorizedAccessResponse)
router.Run(":8080")
}
func SetMerchantDatabase(c *gin.Context){
subdomain := strings.Split(c.Request.Host, ".")
if len(subdomain) > 0{
config.Database = subdomain[0]
config.CurrentBusinessName = subdomain[0]
}else{
errMsg := "Failed: Invalid domain in headers."
response := controllers.ResponseController{
config.FailureCode,
config.FailureFlag,
errMsg,
nil,
}
controllers.GetResponse(c, response)
c.Abort()
}
c.Next()
}
main.go
package main
import (
"cron"
)
func main(){
cron.RunCron()
NewRouter()
}
Explanation of above code
An example route can be:
Route{ "AddCustomer", "POST", "/customer", controllers.SaveCustomer },
An example API url can be:
http://business-name.main-domain.com/api/v1/customer
Where "business-name" is the database which is set whenever an API is called.
I want to run my cron without calling an API route.
Alternative approach
In Shell script, we can run cron by hitting url as a command. For this, I can create a url to run it as a command. But this is my theoratical approach. Also I don't know how will I get different merchant databases.
I am not sure if this approach will work. Any kind of help will be greatly appreciated.

Answer 1

You need to adapt SetMerchantDatabase to work independently of your router. Then you can have it set things for Cron just as well.