Using RegEx in JSON Schema

Question

Trying to write a JSON schema that uses RegEx to validate a value of an item.

Have an item named progBinaryName whose value should adhrere to this RegEx string "^[A-Za-z0-9 -_]+_Prog\\.(exe|EXE)$".

Can not find any tutorials or examples that actually explain the use of RegEx in a JSON schema.

Any help/info would be GREATLY appreciated!

Thanks, D

JSON SCHEMA

{
    "name": "string",
    "properties": {
        "progName": {
            "type": "string",
            "description": "Program Name",
            "required": true
        },
        "ID": {
            "type": "string",
            "description": "Identifier",
            "required": true
        },
        "progVer": {
            "type": "string",
            "description": "Version number",
            "required": true
        },
        "progBinaryName": {
            "type": "string",
            "description": "Actual name of binary",
            "patternProperties": {
                "progBinaryName": "^[A-Za-z0-9 -_]+_Prog\\.(exe|EXE)$"
            },
            "required": true
        }
    }
}

ERRORS:

Warning! Better check your JSON.

Instance is not a required type - http://json-schema.org/draft-03/hyper-schema#

Schema is valid JSON, but not a valid schema.

Validation results: failure

[ {
    "level" : "warning",
    "schema" : {
        "loadingURI" : "#",
        "pointer" : ""
    },
    "domain" : "syntax",
    "message" : "unknown keyword(s) found; ignored",
    "ignored" : [ "name" ]
}, {
    "level" : "error",
    "domain" : "syntax",
    "schema" : {
        "loadingURI" : "#",
        "pointer" : "/properties/ID"
    },
    "keyword" : "required",
    "message" : "value has incorrect type",
    "expected" : [ "array" ],
    "found" : "boolean"
}, {
    "level" : "error",
    "domain" : "syntax",
    "schema" : {
        "loadingURI" : "#",
        "pointer" : "/properties/progBinaryName"
    },
    "keyword" : "required",
    "message" : "value has incorrect type",
    "expected" : [ "array" ],
    "found" : "boolean"
}, {
    "level" : "error",
    "schema" : {
        "loadingURI" : "#",
        "pointer" : "/properties/progBinaryName/patternProperties/progBinaryName"
    },
    "domain" : "syntax",
    "message" : "JSON value is not a JSON Schema: not an object",
    "found" : "string"
}, {
    "level" : "error",
    "domain" : "syntax",
    "schema" : {
        "loadingURI" : "#",
        "pointer" : "/properties/progName"
    },
    "keyword" : "required",
    "message" : "value has incorrect type",
    "expected" : [ "array" ],
    "found" : "boolean"
}, {
    "level" : "error",
    "domain" : "syntax",
    "schema" : {
        "loadingURI" : "#",
        "pointer" : "/properties/progVer"
    },
    "keyword" : "required",
    "message" : "value has incorrect type",
    "expected" : [ "array" ],
    "found" : "boolean"
} ]

Problem with schema#/properties/progBinaryName/patternProperties/progBinaryName : Instance is not a required type
Reported by http://json-schema.org/draft-03/hyper-schema#
Attribute "type" (["object"])

What is not working? (You might want to put that hyphen at the end of the character class) — Martin Ender, May 10 '13 at 23:00
What does "does not work right" mean? Do you get false positives? Do you get false negatives? Do you get some kind of error? — Martin Ender, May 10 '13 at 23:05
Validation fails with errors. http://json-schema-validator.herokuapp.com/syntax.jsp http://jsonschemavalidator.herokuapp.com/ http://jsonschemalint.com/ Too many to list. — Destroyer, May 10 '13 at 23:08
Don't you think it might help potential answerers if you included those error messages in the question? — Martin Ender, May 10 '13 at 23:12
Example repo https://github.com/rofrol/ajv-regexp-errormessage-example — rofrol, Jan 11 '21 at 20:35

score 69 · Accepted Answer · answered Jul 18 '13 at 12:33

69

To test a string value (not a property name) against a RegEx, you should use the "pattern" keyword:

{
    "type": "object",
    "properties": {
        "progBinaryName": {
            "type": "string",
            "pattern": "^[A-Za-z0-9 -_]+_Prog\\.(exe|EXE)$"
        }
    }
}

P.S. - if you want the pattern to match the key for the property (not the value), then you should use "patternProperties" (it's like "properties", but the key is a RegEx).

answered Jul 18 '13 at 12:33

cloudfeet

12,156
1
56
57

1

Is it possible to have case insensitive pattern matching? – Ninja Jul 10 '18 at 10:07
1

@Ninja it seems it can be done only via properly designed regular expression. Check https://json-schema.org/understanding-json-schema/reference/regular_expressions.html - usage of flags is not within recommended RegExp syntax for JSON Schema due to interoperability reasons. – PsychoFish Nov 16 '18 at 00:55
@Ninja for cace insensitive look at https://stackoverflow.com/questions/41874810/make-json-schema-pattern-case-insensitive/65673578#65673578 – rofrol Jan 11 '21 at 19:50

score 13 · Answer 2 · answered May 11 '13 at 10:34

13

Your JSON schema syntax is incorrect. Change

"patternProperties": {
    "progBinaryName": "^[A-Za-z0-9 -_]+_Prog\\.(exe|EXE)$"
    }

to

"patternProperties": {
    "^[A-Za-z0-9 -_]+_Prog\\.(exe|EXE)$": {}
    }

answered May 11 '13 at 10:34

Lodewijk Bogaards

19,777
3
28
52

1

Thank you for providing an answer and not wasting my time. Much, much appreciated! – Destroyer May 22 '13 at 00:13
2

Wasn't the question was about testing the *value*, not the property name? – cloudfeet Jul 18 '13 at 12:30

Using RegEx in JSON Schema

2 Answers2

Linked