https://github.com/radeusgd/jsonrewriter
Scala utility for converting data in JSON between expected formats
https://github.com/radeusgd/jsonrewriter
Last synced: 2 months ago
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Scala utility for converting data in JSON between expected formats
- Host: GitHub
- URL: https://github.com/radeusgd/jsonrewriter
- Owner: radeusgd
- Created: 2018-03-07T22:33:33.000Z (about 7 years ago)
- Default Branch: master
- Last Pushed: 2018-03-08T21:18:08.000Z (about 7 years ago)
- Last Synced: 2025-01-25T11:41:32.967Z (4 months ago)
- Language: Scala
- Size: 10.7 KB
- Stars: 0
- Watchers: 2
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
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README
# JSON Rewriter
A functional utility library for quickly writing JSON converters.
Useful for situations when you have two endpoints using JSON
that communicate similar data, however in slightly different formats.
## Examples
Full code is in `examples` package.
#### [Example 1] Convert some formats
Input:
```
{"user":{"age": 30, "names": "Jack Oliver Jake", "lastname": "King"}, "profile": {"adclicks": [0,1,2,3]}}
{"user":{"age": 45, "names": "Emma Amelia Margaret", "lastname": "Smith"}, "profile": {"adclicks": [0,1]}}
{"user":{"age": 26, "names": "Thomas", "lastname": "Martin"}, "profile": {"adclicks": []}}
```
Conversion function:
```scala
val convert: JsValue => JsValue =
asJsObject _ |> compose[JsObject](
_.mapChild("user", _.asJsObject.rename("lastname", "surname")), // rename property
_.mapDescendant("user.age", (j: JsValue) => j.asJsNumber.map(_ * 365)), // estimate age in days
_.mapDescendant("user.names", (j: JsValue) => // convert names to array of strings
JsArray(j.asString.split(' ').toVector.map(JsString(_))))
)
```
Output:
```
{"user":{"age":10950,"names":["Jack","Oliver","Jake"],"surname":"King"},"profile":{"adclicks":[0,1,2,3]}}
{"user":{"age":16425,"names":["Emma","Amelia","Margaret"],"surname":"Smith"},"profile":{"adclicks":[0,1]}}
{"user":{"age":9490,"names":["Thomas"],"surname":"Martin"},"profile":{"adclicks":[]}}
```
#### [Example 2] Group keys into objects
Input:
```
{"name": "John", "mother_name": "Emma", "mother_age": 35, "father_name": "Thomas", "father_age": 40}
{"name": "Emma", "mother_name": "Olivia", "mother_age": 30, "father_name": "Jack", "father_age": 29}
```
Conversion function:
```scala
val groupParents: JsValue => JsValue =
asJsObject _ |> compose[JsObject](
_.groupAndRename(Map("mother_name" -> "name", "mother_age" -> "age"), "mother"),
_.groupAndRename(Map("father_name" -> "name", "father_age" -> "age"), "father")
)
```
Output:
```
{"mother":{"name":"Emma","age":35},"name":"John","father":{"name":"Thomas","age":40}}
{"mother":{"name":"Olivia","age":30},"name":"Emma","father":{"name":"Jack","age":29}}
```
#### [Example 3] Group keys into an array
Input:
```
{"bikeid": "RC4963", "owner1": "Peter", "owner2": "Amelia", "owner3": "Jack", "owner4": "John"}
{"bikeid": "RK2528", "owner1": "Thomas", "owner2": null, "owner3": "Jack", "owner4": "Margaret", "repairs": 4}
{"bikeid": "RC4694", "owner1": null, "owner2": null, "owner3": null, "owner4": null}
```
Conversion function:
```scala
val arrayize: JsValue => JsValue =
asJsObject _ |> compose[JsObject](
_.mapChildrenToArray(Vector("owner1", "owner2", "owner3", "owner4"), "owners"),
_.mapChild("owners", _.asJsArray.filter(_ != JsNull)) // throw away empty values
)
```
Output:
```
{"owners":["Peter","Amelia","Jack","John"],"bikeid":"RC4963"}
{"owners":["Thomas","Jack","Margaret"],"bikeid":"RK2528","repairs":4}
{"owners":[],"bikeid":"RC4694"}
```