jo and jg comparison and cheatsheet

jo and jg comparison and cheatsheet.md

jo and jg comparison and cheatsheet

What is it?

Both command line utilities allow to JSON output from a shell.

Links

• https://github.com/jawher/jg
• https://github.com/jpmens/jo

Basics

jo string=name integer=1457081292 float=12.3456 float2=1e-5 nil= boolean=true
{"string":"name","integer":1457081292,"float":12.3456,"float2":1e-05,"nil":null,"boolean":true}

Note that jo preserves key order

jg string=name integer=1457081292 float=:12.3456 float2=:1e-5 nil=:null boolean=:true
{"boolean":true,"float":12.3456,"float2":1e-05,"integer":"1457081292","nil":null,"string":"name"}

Note that jg sorts keys alphabetically

Keys merging

jo keeps all the keys (and generates invalid JSON as per rfc4627 The names within an object SHOULD be unique.)

jo a=1 a=2 a=3
{"a":1,"a":2,"a":3}

jg merge keys and last key wins (it's the same what jq does parsing JSON)

jg a=1 a=2 a=3
{"a":"3"}

Arrays

jo -a 1 2 3
[1,2,3]

seq 3 | jo -a
[1,2,3]

jo array[]=1 array[]=2 array[]=3
{"array":[1,2,3]}

jg [:1 :2 :3]
[1,2,3]

jg array=[:1 :2 :3]
{"array":[1,2,3]}

Array of objects

jo -a $(jo id=1) $(jo id=2)
[{"id":1},{"id":2}]

jg [id=:1 id=:2]
[{"id":1},{"id":2}]

Deep objects

jo a=$(jo a=1 b=2) b=$(jo a=3 b=4)
{"a":{"a":1,"b":2},"b":{"a":3,"b":4}}

jo a[a]=1 a[b]=2 b[a]=3 b[b]=4
{"a":{"a":1,"b":2},"b":{"a":3,"b":4}}

jg a={a=:1 b=:2} b={a=:3 b=:4}
{"a":{"a":1,"b":2},"b":{"a":3,"b":4}}

jg a.a=:1 a.b=:2 b.a=:3 b.b=:4
{"a":{"a":1,"b":2},"b":{"a":3,"b":4}}

jg a.b.c=value
{"a":{"b":{"c":"value"}}}

jo and booleans

jo bool@T
{"bool":true}
jo bool@F
{"bool":false}

jo bool@t
{"bool":true}
jo bool@f
{"bool":false}

jo bool@1
{"bool":true}
jo bool@0
{"bool":false}

jo and reading from files

cat a
eiri@eiri.ca

jo email=@a encoded=%a
{"email":"eiri@eiri.ca","encoded":"ZWlyaUBlaXJpLmNhCg=="}

jg and multiline object or arrays

jg {key=a} {key=b}
{"key":"a"}
{"key":"b"}

jg [key=a] [key=b]
[{"key":"a"}]
[{"key":"b"}]

Summary

jo is more convinient when you need to work with files and pipes. jq works better with deep objects and multiline JSON