AJV - Help understand strictmode warnings - jsonschema

Question

I have the following json schema:
{
"$schema": "http://json-schema.org/draft-07/schema#",
"type": "object",
"title": "Form Field configuration",
"properties": {
"title": {
"type": "string",
"title": "The field label"
},
"description": {
"type": "string",
"title": "The field description"
},
"presentation": {
"additionalProperties": false,
"type": "object",
"title": "Configuration for the field visual UI",
"properties": {
"inputType": {
"title": "The recommend way to represent the field visually.",
"anyOf": [
{
"const": "text",
"title": "Similar to the HTML `<input>` with text type."
},
{
"const": "number",
"title": "Similar to the HTML `<input>` with number type."
},
{
"const": "money",
"title": "Similar to 'number', dedicated to monetary values."
}
]
},
"currency": {
"title": "For inputType=money. Monetary Currency Code (3 digits)",
"maxLength": 3,
"minLength": 3,
"type": "string"
},
"description": {
"type": "string",
"title": "The field description with HTML"
}
}
},
"$template": {
"type": "string",
"title": "Pass the template URL to a given field"
}
},
"required": ["presentation"],
"allOf": [
{
"$comment": "Extend the base Draft-07 configuration",
"$ref": "http://json-schema.org/draft-07/schema#"
},
{
"$comment": "Add presentation validations only when $template is not present.",
"if": { "required": ["$template"] },
"else": {
"properties": {
"presentation": {
"$ref": "#/$defs/presentation_validations"
}
}
}
},
{
"if": {
"$comment": "If it contains presentation.description, then [root].description is also required.",
"properties": {
"presentation": {
"required": ["description"]
}
}
},
"then": {
"required": ["description"]
}
}
],
"$defs": {
"presentation_validations": {
"allOf": [
{
"required": ["inputType"]
},
{
"if": {
"properties": {
"inputType": { "const": "money" }
},
"required": ["inputType"]
},
"then": {
"required": ["currency"]
},
"else": {
"properties": { "currency": false }
}
}
]
}
}
}
If I log the strict mode warnings, I get the following warnings:
strict mode: required property "$template" is not defined at "#/allOf/1/if" (strictRequired)
strict mode: missing type "object" for keyword "required" at "#/$defs/presentation_validations/allOf/0" (strictTypes)
strict mode: required property "inputType" is not defined at "#/$defs/presentation_validations/allOf/0" (strictRequired)
strict mode: missing type "object" for keyword "required" at "#/$defs/presentation_validations/allOf/1/if" (strictTypes)
strict mode: missing type "object" for keyword "properties" at "#/$defs/presentation_validations/allOf/1/if" (strictTypes)
strict mode: missing type "object" for keyword "required" at "#/$defs/presentation_validations/allOf/1/then" (strictTypes)
strict mode: required property "currency" is not defined at "#/$defs/presentation_validations/allOf/1/then" (strictRequired)
strict mode: missing type "object" for keyword "properties" at "#/$defs/presentation_validations/allOf/1/else" (strictTypes)
strict mode: missing type "object" for keyword "required" at "#/allOf/2/if/properties/presentation" (strictTypes)
strict mode: required property "description" is not defined at "#/allOf/2/if/properties/presentation" (strictRequired)
strict mode: required property "description" is not defined at "#/allOf/2/then" (strictRequired)
But I don't understand what do I need to change and, most importantly, when I need to do them, as if I validate against some jsons, they work as expected.
Here's the codesandbox: https://codesandbox.io/s/ajv-strict-mode-warnings-b88re5

Answer 1

AJV's "strict mode" prevents you from making common mistakes which could lead to creating a JSON Schema which is less specified (or "more underspecified") than you expect.
Let's take the first error you see.
strict mode: missing type "object" for keyword "required" at "#/allOf/1/if/properties/presentation" (strictTypes)
The required keyword only applies to objects. This means if the instance data at that location was of another type, say, a string, then validation would pass. The required keyword doesn't mean it has to be an object. If you want it to be an object, you need to additionally specify such using the type keyword.
AJV's strict mode rule "strictTypes" explicitly requires that you specify the types if you use keywords which are only applied based on their type.
Consider a JSON Schema such as { "required": "name" }. If the instance was an object, "name" would be required. However, if the instance data was in stead an array [], it would also pass validation for the given schema in this example.

Answer 2

In addition to the answer of #relequestual. There is a built-in linter/analyzer in JSONBuddy and it shows a major issue in your schema immediately:
There is a $ref at the same schema as other keywords. Prior to draft 2019-09 all of the keywords next to $ref at the same level are ignored during validation.
AJV does not complain as you are using draft 7? Is this also present in your copy?
Often, a possible solution for an error like this is to use allOf and wrap the $ref and all other definitions in two separate (sub)schemas. Like:
"allOf": [
{ "$ref": "myref" },
{ ... all other definitions ... }
]