Retrieve specific properties from a given JSON file

Question

I'm trying to query a JSON file with a JSONPath expression, executed with a JObject.selectTonkens() call. Unfortunately, I don't get the expected output.

I have tried many ways on https://jsonpath.com/ and with Newtonsoft.

These are the several attempts that do not give me the expected result :

IEnumerable<JToken> rawProperties = obj.SelectTokens("$.properties[?(@..type)]");
foreach (JToken token in rawProperties)
{
    Console.WriteLine(token);
}

This does give me every property (including the ones I don't want) that do have a type. I've tried it in visual studio.

Best attempt :

$.properties[?(@.type != 'array')]

I've tried it on https://jsonpath.com/ , unfortunately, it does not work at all on Visual Studio. It gives me the good expected result but without the keys I need (cf expected output at the end of my post) :

[
  {
    "type": "string",
    "description": "Identifiant technique de l'action de régulation."
  },
  {
    "type": "string",
    "description": "Description de l'action de régulation."
  },
  {
    "type": "string",
    "description": "situations/id : identifiant technique de la situation."
  }
]

This is a sample of the JSON file I'm trying to query :

{
"$schema": "http://json-schema.org/draft-04/schema#",
"title": "actionRegulation",
    "type": "object",
    "properties": {
        "id": {
            "type": "string",
            "description": "Identifiant technique de l'action de régulation."
        },
        "description": {
            "type": "string",
            "description": "Description de l'action de régulation."
        },
        "idSituation": {
            "type": "string",
            "description": "situations/id : identifiant technique de la situation."
        },
        "pointsJalonnement": {
      "type": "array",
      "items": {
        "title": "PointJalonnement",
        "type": "object",
        "properties": {
          "rang": {
            "type": "integer",
            "description": "Rang du point de jalonnement."
          },
          "refJalon": {
            "type": "string",
            "description": "Référence du point de jalonnement (PR/CR-CI-CH)."
          },
          "typeModification": {
            "type": "string",
            "description": "Renseigné que si modification d'horaire (utile à IENA)."
          }
        }
      }
    }
   }
}

I want to retrieve all the properties (including their name, like "id", "description") but that are not a "type":"array" and that do not belong to an "array" type object, that is to say that are inner properties. I for example do not want to retrieve from my query "refJalon", "typeModification", etc. So I expect to have the following result from my query :

[
"id":
  {
    "type": "string",
    "description": "Identifiant technique de l'action de régulation."
  },
"description":
  {
    "type": "string",
    "description": "Description de l'action de régulation."
  },
"idSituation":
  {
    "type": "string",
    "description": "situations/id : identifiant technique de la situation."
  }
]

Any piece of help would be really appreciated : other technologies/frameworks I should use, some specific documenation, etc. Thanks!

Answer 1

You may not be able to get the result you want using JsonPath; there are limitations as @dbc mentioned in the comments. However, you can get the results you want using a pretty straightforward LINQ-to-JSON query:

IEnumerable<JToken> rawProperties = obj["properties"]
    .Children<JProperty>()
    .Where(jp => (string)jp.Value["type"] != "array");

foreach (JToken token in rawProperties)
{
    Console.WriteLine(token);
}

Fiddle: https://dotnetfiddle.net/A4ZbEG