aeson-jsonpath

Run RFC 9535 compliant JSONPath queries on Data.Aeson.

Roadmap

• Selectors
  • Name Selector
  • Index Selector
  • Slice Selector
  • Wildcard Selector
  • Filter Selector
• Segments
  • Child Segment
  • Descendant Segment
• Normalized Paths
• Function Extensions

I have decided not to implement Function Extension yet. Please open an issue or discussion if you'd like to see them implemented.

Quick Start

{-# LANGUAGE QuasiQuotes #-} import Data.Aeson (Value (..)) import Data.Aeson.QQ.Simple (aesonQQ) import Data.Aeson.JSONPath (query, queryLocated, jsonPath) track = [aesonQQ| { "artist": "Duster", "title": "Earth Moon Transit" } |] ghci> query "$.artist" track -- child member shorthand Right [String "Duster"] ghci> queryLocated "$.*" track -- child wildcard segment Right [ ("$['artist']", String "Duster"), ("$['title']", String "Earth Moon Transit") ] 

More Examples

{-# LANGUAGE QuasiQuotes #-} import Data.Aeson (Value (..)) import Data.Aeson.QQ.Simple (aesonQQ) import Data.Aeson.JSONPath (query, queryLocated, jsonPath) json = [aesonQQ| { "shop": { "movies": [ { "title": "Mandy", "director": "Panos Cosmatos", "year": 2018 }, { "title": "Laurence Anyways", "director": "Xavier Dolan", "year": 2012 } ] } }|] 

Child Segment

ghci> query "$.shop.movies[0].title" json Right [String "Mandy"] ghci> query "$.shop.movies[0].*" json Right [ String "Mandy", String "Panos Cosmatos", Number 2018.0 ] ghci> query "$['shop']['new-movies']" json Right [] 

Descendant Segment

-- get all values with key "director", recursively ghci> query "$..director" json Right [ String "Panos Cosmatos", String "Xavier Dolan" ] 

Slice Selector

ghci> query "$[2:5]" [aesonQQ| [1,2,3,4,5,6] |] Right [ Number 3.0, Number 4.0, Number 5.0 ] 

Filter Selector

ghci> query "$.shop.movies[?@.year < 2015]" json Right [ Object (fromList [ ("director",String "Xavier Dolan"), ("title",String "Laurence Anyways"), ("year",Number 2012.0) ]) ] ghci> queryLocated "$.shop.movies[?@.director == 'Panos Cosmatos']" json Right [ ( "$['shop']['movies'][0]", Object (fromList [ ("director",String "Panos Cosmatos"), ("title",String "Mandy"), ("year",Number 2018.0) ]) ) ] 

QuasiQuoter

The functions queryQQ and queryLocatedQQ can be used with the jsonPath quasi quoter.

queryQQ [jsonPath|$.shop.movies|] json -- compiles successfully queryQQ [jsonPath|$.shop$$movies|] json -- compilation error, doesn't parse 

Testing

It is tested using 10000+ lines test suite given by jsonpath-compliance-test-suite 🚀.

Note: All tests pass except tests related to function extensions which we have not implemented yet.

Development

Please report any bugs you encounter by opening an issue.