Comparator

Introduction

A comparator is a JSON object that tells the program how to compare the data fetched from the loader.

Possible values

And

Will match if all the comparators contained match.

Example:

{
    "and": [
        {"regex": "^start_"},
        {"regex": "_end$"},
    ]
}

Glob

Will perform a glob match on the data. Multiple patterns can be used with the ";" separator.

Example:

{
    "glob": "*.jpg; *.png"
}

In

Will match if the data is one of the values in the list. Comparison is case-insensitive by default.

Supports both string and numeric values.

Example:

{
    "in": ["jpg", "jpeg", "png"]
}

With case-sensitive matching:

{
    "in": ["image/jpeg", "image/png"],
    "case_sensitive": true
}

Not

Will match if the wrapped comparator does not match.

Example:

{
    "not": {"glob": "*.tmp"}
}

Or

Will match if one of the comparators contained match. Comparators are evaluated in order.

Example:

{
    "or": [
        {"regex": "^start_"},
        {"regex": "_end$"},
    ]
}

Range

Will perform a range check on the data. One or both of min and max can be set. min is inclusive, max is exclusive.

Supports both numbers and dates. Dates are parsed with the ISO 8601 format.

Example:

{
    "min": 100,
    "max": 200
}

{
    "min": "2017-07-24T15:46:29"
}

Regex

Will perform a regex match on the data.

Example:

{
    "regex": "^start_with_"
}

Capture groups

Named and positional capture groups are extracted on a successful match and made available as template variables in other actions via {captures.$data.$group}, where:

• $data: the loader key of the condition, or "content" for content loaders
• $group the group index, or name when using named groups: (?P<name>...)

With "data": "filename" and "regex": "(?P<title>.+)-(\\d+)\\.jpg", a match on photo-42.jpg exposes:

• {captures.filename.title}: photo
• {captures.filename.1}: photo (same group but by position)
• {captures.filename.2}: 42

These values are usable in any action template in the same rule. For example, to rename photo-2024-06-01.jpg into 2024-06-01-photo.jpg:

{
    "name": "Rename photos",
    "conditions": [
        {
            "data": "stem",
            "regex": "(?P<name>.+)-(?P<date>\\d{4}-\\d{2}-\\d{2})"
        }
    ],
    "actions": {
        "type": "rename",
        "dest": "{captures.stem.date}-{captures.stem.name}.{extension}"
    }
}

Composite comparators

• and / or: when multiple regex comparators are composed, all of them write into the same capture map. Positional indices are shared and the last-evaluated regex wins. Prefer named groups ((?P<name>...)) whenever captures will be used in templates inside a composite condition.
• not: the inner comparator's captures are passed through even when not inverts the result.