How to convert string claims to a List

Question

I am getting back a JWT Token and I am using the System.IdentityModel.Tokens.Jwt to decode it so I can do validation on the token. I am able to strip the claims up to this point:

"{\"Account Manager\":\"true\",\"Administrator\":\"true\",\"Agent\":\"true\"}"

What I want is a List<string> that looks like this:

"Account Manager"
"Administrator"
"Agent"

What is the best way to handle this?

Looks like a job for `Newtonsoft.JSON` `.DeserializeObject()` (https://www.newtonsoft.com/json/help/html/M_Newtonsoft_Json_JsonConvert_DeserializeObject__1_1.htm) — Ryan Wilson, Jul 22 '19 at 21:07
What language is the string written in? It appears to be JSON; is it? — Eric Lippert, Jul 22 '19 at 21:07
@EricLippert Its originally a JWT token, When it gets Decoded it is a C# string, that looks like JSON — Robert, Jul 22 '19 at 21:09
first thing I would do is to replace \" with " then use NewtonsoftJSON to deserialize — curiousBoy, Jul 22 '19 at 21:09
@curiousBoy I'm like 99% sure that it's just the debug view and that the real string doesn't actually contain \. — Etienne de Martel, Jul 22 '19 at 21:10
@Robert - look at this post. It may help you to get what you need: https://stackoverflow.com/questions/5546142/how-do-i-use-json-net-to-deserialize-into-nested-recursive-dictionary-and-list — curiousBoy, Jul 22 '19 at 21:14
How exactly are you decoding the token? I wouldn't expect you to need to manually parse JSON here. — Kirk Larkin, Jul 22 '19 at 21:20

score 1 · Answer 1 · answered Jul 22 '19 at 21:16

1

You need something like that:
var claims = Newtonsoft.Json.JsonConvert.DeserializeObject<List<string>>(data);

answered Jul 22 '19 at 21:16

Y.Y.

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score 1 · Accepted Answer · answered Jul 22 '19 at 21:32

@Kirk has a good point, how are you decoding the token? It's a little strange to be dealing with the JSON string directly. Normally you'd decode it into a JwtSecurityToken and access the ClaimsPrincipal and Claims under that (see here for some info that may help). Nevertheless, if you're determined to forge ahead, this is how I'd do it.

You have a bunch of key-value pairs, and I'm assuming you only want a list of the values where the claim value is true. I'd filter them as follows:

    string json = "{\"Account Manager\":\"true\",\"Administrator\":\"true\",\"Agent\":\"true\"}";

    var vals = JsonConvert.DeserializeObject<Dictionary<string, string>>(json);
    var list = vals.Where(v => v.Value == "true").Select(v => v.Key);

    Console.WriteLine(string.Join(Environment.NewLine, list));

How to convert string claims to a List

2 Answers2