Can not search substrings when JSON is nested

[aikrikunov95]

I want to write a string which represents nested JSON object to disk and get beginning indexes of some inner objects. The problem is that I store an inner object as string, not JSON object, in order to ensure that a digital signature function will always receive the same input. When I encode the most outer object to string, the inner one becomes escaped and I can't find initial un-escaped version in the resulting string. Consider the following example:

val messageContent = MessageContent(
    type = "createGroup",
    groupTitle = "Test title",
    timestamp = 0
)
val messageContentString = Json.encodeToString(messageContent)

{
    "type":"createGroup",
    "timestamp":0,
    "groupTitle":"My title"
}

val signedMessage = SignedMessage(
    contentString = messageContentString,
    memberPublicKey = "xxx",
    contentSignature = "yyy"
)
val signedMessageString = Json.encodeToString(signedMessage)

{
    "contentString":"
        {
            \"type\":\"createGroup\",
            \"timestamp\":0,
            \"groupTitle\":\"My title\"
        }",
    "memberPublicKey":"xxx",
    "contentSignature":"yyy"
}

I'm trying to search messageContentString in signedMessageString but it's escaped with backslashes and my search fails.

Is there a way to un-escape resulting string so I can search inside it, or should I stop storing JSON objects as strings in general? Thanks.

[sandwwraith]

There's no way to do this for now, but it looks like a use case for #1405 (comment)

[shanshin]

Implemented in #2041