Confused by JSON-schema format

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cuthbert

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Mar 19, 2015, 5:34:49 PM3/19/15
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Hi, I'm wondering if anyone could clarify something i'm stuck on.

i have some json i want to validate. it is in the following format :

{
  "fixedKey": {
    "1": {}
  }
}

In the object the key "fixedKey" will never change, it is hard coded in the structure. 

The key "1" I wish to validate, but it could be any numerical value so i've written the json schema below to check it's of the pattern [0-9]*

{
    "type": "object",
    "properties": {
        "fixedKey": {
            "type": "object",
            "patternProperties": {
                "[0-9]*": {}
            }
        }
    }
}

my problem is when testing here http://jsonschemalint.com/draft4/#

the json always passes even if the second key is not numeric. 

could someone point out where i've gone wrong please
thanks :-)

Mike Lorbetske

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Mar 19, 2015, 6:04:04 PM3/19/15
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The schema you're using specifies that properties that match that regex must validate against the empty schema but does not say those are the only properties allowed. Add "additionalProperties": false as a peer to your patternProperties member to disallow undeclared property names.

Thanks,
Mike
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From: cuthbert
Sent: ‎3/‎19/‎2015 2:34 PM
To: json-...@googlegroups.com
Subject: [json-schema] Confused by JSON-schema format

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Geraint

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Mar 20, 2015, 9:36:32 AM3/20/15
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In addition to "additionalProperties": false as Mike said, you should also fix your regular expression.

Firstly, you've used the asterisk "*", which means "zero or more".  You probably want plus "+", which means "one or more".

You should also put the start/end in there, because by default regular expressions are not anchored.

So: "^[0-9]+$" would match a series of decimal characters.  If you don't want leading zeros, you could use "^(0|[1-9][0-9]*)$".

cuthbert

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Mar 21, 2015, 6:25:52 AM3/21/15
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thanks for your help guys but i stil can't get this to work...

i'm using this helper here: http://www.jsonschemavalidator.net/

using this schema it fails to compile

{
    "type": "object",
    "properties": {
        "fixedKey": {
            "type": "object",
            "properties": {
                "patternProperties": {
                    "^(0|[1-9][0-9]*)$": {}
                },
                "additionalProperties": false
            }
        }
    }
}

Unexpected token encountered when reading value for 'additionalProperties'. Expected StartObject, got Boolean. Path 'properties.fixedKey.properties.additionalProperties', line 10, position 46.

running the code against this https://github.com/mafintosh/is-my-json-valid doesn't complain but thinks my test json is ok when it should fail for not matching the regex

if i move out the "additionalProperties":false out to the next level that looks wrong as it rejects any value that is present

{
    "type": "object",
    "properties": {
        "fixedKey": {
            "type": "object",
            "properties": {
                "patternProperties": {
                    "^(0|[1-9][0-9]*)$": {}
                }
            },
            "additionalProperties": false
        }
    }
}

still confused...
Message has been deleted

Sebastian Lasse

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Mar 21, 2015, 12:05:29 PM3/21/15
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Two bugs in your Schema !

  • The "additionalProperties" must be on the same 'level' than "patternProperties".
  • "patternProperties" is a replacement for "properties" (properties that are defined as patterns)

It should just read:

...

"patternProperties": {
    "^(0|[1-9][0-9]*)$": {}
},
"additionalProperties": false

...

Sebastian Lasse

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Mar 21, 2015, 12:07:58 PM3/21/15
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Be sure to read the official Specifications ...

cuthbert

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Mar 21, 2015, 12:47:20 PM3/21/15
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yes, I've tried that, it doesn't behave as expected in the tools indicated

xmlbuddy

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Mar 22, 2015, 3:14:57 PM3/22/15
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Hi,

the following JSON schema works for your example validated with the standard Java JSON schema validator version 2.2.5 (Java lib available here):

Regards
Clemens
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