Access root data in code generation custom keyword

What version of Ajv you are you using? 7.2.3

What problem do you want to solve? I’m trying to validate whether array items are used as object keys.

Let’s say I have a schema like this

{
	"keys": {
		"type": "array",
		"arrayItemsAreKeysOf": "/specialObject" // attempting to implement this custom keyword
	},
	"specialObject": {
		"type": "object"
	}
}

This is valid:

{
	"keys": ["one", "two"],
	"specialObject": {
		"one": true,
		"two": true
	}
}

This is invalid:

{
	"keys": ["one", "two", "three"],
	"specialObject": {
		"one": true,
		"two": true
	}
}

What do you think is the correct solution to problem? In ajv v6 I had a custom “validate” function to check this:

ajv.addKeyword('arrayItemsAreKeysOf', {
	validate(schema, data, parentSchema, dataPath, parentData, propertyName, rootData) {
		const validArrayItems = R.pipe(
			R.path(schema.split('/')),
			R.keys,
		)(rootData);
		return R.all(R.includes(R.__, validArrayItems))(data);
	},
	errors: false,
});

(If you’re unfamiliar with Ramda, this takes the keys of a given path (/specialObject) from rootData and then checks if all items of data (keys array in examples) are present)

And it worked fine. I tried rewriting this for ajv v7+ using the code generation keyword, but I’m not sure if it’s possible to access rootData there.

Will you be able to implement it? Maybe it’s already possible to do what I’m trying to achieve?

[domnantas]

I have rewritten the above v6 code to v7, took rootData from dataCtx:

ajv.addKeyword('arrayItemsArePropertiesOf', {
	validate(schema, data, parentSchema, dataCtx) {
		const validArrayItems = R.pipe(
			R.path(schema.split('/')),
			R.keys,
		)(dataCtx.rootData);

		return R.all(R.includes(R.__, validArrayItems))(data);
	},
});

So rootData is only accessible in validation functions and not in code generation functions, right?

[domnantas]

To make it slightly more clear for anyone stumbling on this, this is how you access the rootData in the code function:

ajv.addKeyword({
  keyword: "even",
  code(cxt: KeywordCxt) {
    cxt.fail(_`console.log(data)`) // data here returns the "rootData" 
  },
})