Check if a key exists in play.api.libs.json.Json

Question

contains like functionality for play.api.libs.json.Json

val data=Map("id" -> "240190", "password" -> "password","email" -> "email@domain.com")

data.contains("email")//true


val info=Json.obj("id" -> "240190", "password" -> "password","email" -> "email@domain.com")

now how to check info contains email or not?

score 23 · Accepted Answer · answered Jul 23 '14 at 07:49

23

info.keys.contains("email")

The .keys gives you back a Set with the key values and then you can call the contains method, I'm not sure there's a more direct way to do it.

answered Jul 23 '14 at 07:49

Ende Neu

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`keys` yields a `Set`. – Kigyo Jul 23 '14 at 07:51
Thanks, It was a typo. – Ende Neu Jul 23 '14 at 07:52

Mahesh Pujari · Answer 2 · 2017-07-23T17:02:53.910

7

(info \ "email").asOpt[String].isEmpty

as asOpt would return Optional, we can have isEmpty simple check, this would do what we want.

edited Jul 23 '17 at 17:02

answered Jul 22 '17 at 12:18

Mahesh Pujari

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Some explanation might help future visitors. – Gaurav Gandhi Jul 22 '17 at 22:04
1

@errhunter thankq! as asOpt would return Optional, we can have isEmpty simple check, this would do what we want. – Mahesh Pujari Jul 23 '17 at 11:15
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You can edit your answer to add the explanation, instead of writing it as a comment. – chtz Jul 23 '17 at 16:04

score 6 · Answer 3 · edited Sep 02 '16 at 06:54

6

(info \ "email").asOpt[String] match {
  case Some(data) => println("here is the value for the key email represented by variable data" + data)
  case None => println("email key is not found") 
}

edited Sep 02 '16 at 06:54

dk14

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answered Sep 01 '16 at 06:12

Sangeeta

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This won't work when you do things like `.asOpt[Boolean]`, which will always give you a Some(false) when the key doesn't exist. – chuchao333 Jul 24 '17 at 17:19

Check if a key exists in play.api.libs.json.Json

3 Answers3