Add target_keys property schema

[annakrystalli]

Use additionalProperties to enforce that target_keys properties are strings, not arrays.

Resolves #97

[annakrystalli]

Adding the experimentation test results below, with plans to add specific tests for this in hubAdmin hubverse-org/hubAdmin#54

text_invalid <- '{
    "target_keys": {
        "target": [
            "wk flu hosp rate change"
        ]
    }
}'
text_valid <- '{
    "target_keys": {
        "target": "wk flu hosp rate change"
    }
}'
text_valid_null <- '{
    "target_keys": null
}'

schema_text_vague <- '
{
    "$schema": "https://json-schema.org/draft/2020-12/schema",
    "$id": "https://raw.githubusercontent.com/hubverse-org/schemas/main/v3.0.1/tasks-schema.json",
    "type": "object",
    "properties": {
        "target_keys": {
            "type": [
                "object",
                "null"
                ]

        }

    }
}
'
schema_vague <- jsonvalidate::json_schema$new(schema_text_vague)
schema_vague$validate(text_invalid) # FALSE NEGATIVE
#> [1] TRUE
schema_vague$validate(text_valid)
#> [1] TRUE
schema_vague$validate(text_valid_null)
#> [1] TRUE


schema_text_specific <- '
{
    "$schema": "https://json-schema.org/draft/2020-12/schema",
    "$id": "https://raw.githubusercontent.com/hubverse-org/schemas/main/v3.0.1/tasks-schema.json",
    "title": "Schema for Modeling Hub model task definitions",
    "description": "This is the schema of the tasks.json configuration file that defines the tasks within a modeling hub.",
    "type": "object",
    "properties": {
        "target_keys": {
            "type": [
                "object",
                "null"
                ],
            "additionalProperties": {
                "type": "string"

            }
        }
    }
}
'

schema <- jsonvalidate::json_schema$new(schema_text_specific)
schema$validate(text_invalid)
#> [1] FALSE
schema$validate(text_valid)
#> [1] TRUE
schema$validate(text_valid_null)
#> [1] TRUE

[matthewcornell]

looks good!

[elray1]

agreed, looks good, thanks!