How to create a new JSON object in every loop iteration - ruby-on-rails

Question

I am working on a feature that given my daily work hours and the start and end date of my contract displays in a calendar my work hours. The problem is when I have 2 or more shifts on the same day. Let's say Julian has a shift from 03:00 to 04:00 and another one on the same day from 5:00 to 6:00 every Monday starting from July 17, 2019 to July 31, 2019. That means that my calendar should display these 2 shifts in July 22 and July 29. I have coded the logic to get me the correct dates. As of right now my JSON response looks like this
{"user":"Julian","start":"2019-07-22","day":"Monday","start_time":["03:00","05:00"],"end_time":["04:00","06:00"]},{"user_":"Julian","start":"2019-07-29","day":"Monday","start_time":["03:00","05:00"],"end_time":["04:00","06:00"]}
which is being generated by the following code in my JSON builder file
json.array! event.each do |inevent|
json.id hr_schedule.id
json.user_id hr_schedule.user_id
json.start inevent.strftime('%Y-%m-%d')
day_of_week = inevent.strftime('%A')
json.day day_of_week
if day_of_week == "Monday"
json.start_time hr_schedule.monday_st
json.end_time hr_schedule.monday_end
elsif day_of_week == "Tuesday"
json.start_time hr_schedule.tuesday_st
json.end_time hr_schedule.tuesday_end
elsif day_of_week == "Wednesday"
json.start_time hr_schedule.wednesday_st
json.end_time hr_schedule.wednesday_end
elsif day_of_week == "Thursday"
json.start_time hr_schedule.thursday_st
json.end_time hr_schedule.thursday_end
elsif day_of_week == "Friday"
json.start_time hr_schedule.friday_st
json.end_time hr_schedule.friday_end
elsif day_of_week == "Saturday"
json.start_time hr_schedule.saturday_st
json.end_time hr_schedule.saturday_end
elsif day_of_week == "Sunday"
json.start_time hr_schedule.sunday_st
json.end_time hr_schedule.sunday_end
end
end
what I want to achieve is to be able to have all my events as a unique JSON object like the following
{"user":"Julian","start":"2019-07-22","day":"Monday","start_time":"03:00","end_time":"04:00"},{"user":"Julian","start":"2019-07-22","day":"Monday","start_time":"05:00","end_time":"06:00"},
{"user":"Julian","start":"2019-07-29","day":"Monday","start_time":"03:00","end_time":"04:00"},{"user":"Julian","start":"2019-07-29","day":"Monday","start_time":"05:00","end_time":"06:00"}

Answer 1

I'm not sure what class json is, nor what array! is doing. But the basic way to do what you want is to use map to turn your events into an Array of Hashes. Then turn the Array into JSON with to_json.
calendar = event.map do |inevent|
json = {}
json[:id] = hr_schedule.id
json[:user] = hr_schedule.user_id
json[:start] = inevent.strftime('%Y-%m-%d')
json[:day] = inevent.strftime('%A')
case inevent.wday
when 0
json[:start_time] = hr_schedule.sunday_st
json[:end_time] = hr_schedule.sunday_end
when 1
json[:start_time] = hr_schedule.monday_st
json[:end_time] = hr_schedule.monday_end
when 2
json[:start_time] = hr_schedule.tuesday_st
json[:end_time] = hr_schedule.tuesday_end
when 3
json[:start_time] = hr_schedule.wednesday_st
json[:end_time] = hr_schedule.wednesday_end
when 4
json[:start_time] = hr_schedule.thursday_st
json[:end_time] = hr_schedule.thursday_end
when 5
json[:start_time] = hr_schedule.friday_st
json[:end_time] = hr_schedule.friday_end
when 6
json[:start_time] = hr_schedule.saturday_st
json[:end_time] = hr_schedule.saturday_end
end
json
end
puts calendar.to_json
I've simplified it a bit by using a case/when and Time#wday. strftime(%A) might change if the language of the application changes, and the day of week numbers are harder to typo.
As a side note, this event structure limits itself to only events which end before midnight. Consider instead using a full ISO8061 datetimes for start and end. In general, it's easier to work with a full datetime than separate date and time. The event day can be inferred from start.
{"user":"Julian","start":"2019-07-22T03:00","end":"2019-07-22T04:00"}
Or if the events are relative, like they happen every Monday, consider a start and a duration. And use an ISO weekday number for the day instead of a string, less parsing for the receiver to do.
{"user":"Julian","day":1,"start":"03:00","duration":"P1H"}