typedcsv

Typedcsv

Here's your standard untyped CSV:

name,income,created_at,tags,great
Seamus,12301.2,2012-02-21,"red,blue",true

Now, you and I know that 12301.2 is a number and 2012-02-21 is a date and "red,blue" is a list... so let's just write that into the headers:

name,income:number,created_at:date,tags:list,great:boolean
Seamus,12301.2,2012-02-21,"red,blue",true

Now let's parse it:

Typedcsv.foreach('file.csv', headers: true) do |row|
  row['income']     # will be a Float
  row['created_at'] # will be a Date
  row['tags']       # will be an Array
  row['great']      # will be TrueClass or FalseClass
end

This gem provides Typedcsv.foreach(), which takes exactly the same arguments as ruby stdlib CSV.foreach.

Types

• text (default)
• number
• list (must be comma-separated and therefore quoted)
• date (must be ISO8601)
• time (must be ISO8601)
• boolean (recognizes "true" or "false")

Benchmarks

It's about 10x slower than ruby's stdlib CSV.foreach:

cd benchmark && ruby benchmark.rb
[...]
CSV.foreach - array mode
                          2.503  (± 0.0%) i/s -     13.000  in   5.197588s
Typedcsv.foreach - array mode
                          0.253  (± 0.0%) i/s -      2.000  in   7.892107s
CSV.foreach - hash mode
                          1.830  (± 0.0%) i/s -     10.000  in   5.466998s
Typedcsv.foreach - hash mode
                          0.226  (± 0.0%) i/s -      2.000  in   8.867616s

Sponsor

We use typedcsv for B2C customer intelligence at Faraday.

Copyright

Copyright 2017 Faraday