Ruby : Convert timestamp to date time in given json input

Question

I have a JSON input. I would like to convert all timestamp (createdDate ,modifiedDate) to time in ruby. How do I do that? I tried below methods but dint work

characterList.each { |char| DateTime.strptime(char.try(:getEditInfo).try(:getCreatedDate),%s) } {"characterList": [ {"editInfo": {"createdBy": "testname", "createdDate": 1503137795000, "modifiedBy": "testname", "modifiedDate": 1503137795000}, "charInfo": {"charid": "3434", "charDesc": "3434", "status": "ON"} }, {"editInfo": {"createdBy": "testname", "createdDate": 1503137795000, "modifiedBy": "testname", "modifiedDate": 1503137795000}, "charInfo": {"charid": "3434 6", "charDesc": "43dfdf", "status": "ON"} }, {"editInfo": {"createdBy": "testname", "createdDate": 1503137795000, "modifiedBy": "testname", "modifiedDate": 1503137795000}, "charInfo": {"charid": "4hr_SLA", "charDesc": "sd", "status": "ON"} }, {"editInfo": {"createdBy": "testname", "createdDate": 1503137795000, "modifiedBy": "testname", "modifiedDate": 1503137795000}, "charInfo": {"charid": "aaaaaaaaaa", "charDesc": "asdfaadsf asdfasdf asdf", "status": "ON"} }, {"editInfo": {"createdBy": "testname", "createdDate": 1503137795000, "modifiedBy": "testname", "modifiedDate": 1503137795000}, "charInfo": {"charid": "abababab", "charDesc": "abababababab", "status": "ON"} } ]} 

I am ok converting in 2 like separately for createdDate and modifiedDate. But Im looking for one line solution

Answer 1

You can do something like:

json[:characterList].map! do |character| character.tap do |char| if editInfo = char[:editInfo] if editInfo[:createdDate] editInfo[:createdDate] = DateTime.strptime(editInfo[:createdDate].to_s, '%Q') end if editInfo[:modifiedDate] editInfo[:modifiedDate] =_ DateTime.strptime(editInfo[:modifiedDate].to_s, '%Q') end end end end 

the main issues with your code were

1. No :getEditInfo or :getCreatedDate, though, those may just be methods you made but didn't include here.
2. strptime takes a string, the *Date fields are integers
3. The %s argument to strptime is the number of seconds since 1970-01-01 00:00:00 UTC, I'm going to assume you aren't dealing with dates in the year 49,602, so changed it to %Q, which is the number of milliseconds since 1970-01-01 00:00:00 UTC.

This is just a sample, modifying the JSON hash itself with DateTime objects, you may need to be doing something different with it, the big thing here is the %Q and to_s in strptimes

DateTime.strptime(1503137795000.to_s, '%Q') # => 2017-08-19T10:16:35+00:00 

Without knowing what's actually wrong with your code ("didn't work" isn't very descriptive), if everything else on that line you tried work you could just change to:

characterList.each { |char| DateTime.strptime(char.try(:getEditInfo).try(:getCreatedDate).to_s,'%Q') } 

for a one-liner