kestra-io/kestra · error · PebbleException

The '%s' filter expects a positive integer >=0 as argument '

Error message

The '%s' filter expects a positive integer >=0 as argument 'amount'.

What it means

Thrown by AbstractIndent when the 'amount' argument of the indent or nindent filter is a negative number. The filter requires amount to be zero or positive because a negative repeat count for the prefix string is meaningless.

Source

Thrown at core/src/main/java/io/kestra/core/runners/pebble/AbstractIndent.java:56

        return System.lineSeparator(); // System default
    }

    protected Object abstractApply(Object input, Map<String, Object> args, PebbleTemplate self, EvaluationContext context, int lineNumber, String indentType) throws PebbleException {
        if (input == null) {
            return null;
        }
        if (input.toString().isEmpty()) {
            return input.toString();
        }

        if (!args.containsKey("amount")) {
            throw new PebbleException(null, String.format("The '%s' filter expects an integer as argument 'amount'.", indentType), lineNumber, self.getName());
        }

        int amount = ((Long) args.get("amount")).intValue();
        if (!(amount >= 0)) {
            throw new PebbleException(null, String.format("The '%s' filter expects a positive integer >=0 as argument 'amount'.", indentType), lineNumber, self.getName());
        }

        String prefix = prefix(args);
        String newLine = getLineSeparator(input.toString());

        if (indentType.equals("indent"))
            // indent filter adds N amount of spaces to each line except for the first one (assuming the first line is already indented in place)
            return input.toString().replace(newLine, newLine + prefix.repeat(amount));
        else if (indentType.equals("nindent")) {
            // nindent filter adds a newline to the string and indents each line by defined amount of spaces
            return (newLine + input).replace(newLine, newLine + prefix.repeat(amount));
        }
        throw new PebbleException(null, String.format("Unknown indent type '%s'.", indentType), lineNumber, self.getName());

    }
}

View on GitHub (pinned to 823fada927)

Solutions

1. Change the amount to zero or a positive integer: '{{ text | indent(0) }}' or '{{ text | indent(4) }}'.
2. If the amount is dynamic, clamp it with a max/min expression: '{{ text | indent(max(vars.indent, 0)) }}'.
3. Audit the upstream variable or expression that produces the negative value.

Example fix

{# before #}
{{ text | indent(vars.indent_level) }}
{# where vars.indent_level = -1 #}

{# after #}
{{ text | indent(max(vars.indent_level, 0)) }}

{# Clamp the amount to a minimum of zero before passing it #}
{% set safe_indent = max(vars.indent_amount ?? 0, 0) %}
{{ text | indent(safe_indent) }}

When it happens

Trigger: Passing a negative integer to indent or nindent: '{{ text | indent(-2) }}'. Also possible when the amount comes from a variable or expression that evaluates to a negative value at runtime.

Common situations: A computed amount variable that underflows to negative due to subtraction or a malformed input. Hard-coding a negative value by mistake.

Related errors

• The '%s' filter expects an integer as argument 'amount'.
• Unknown indent type '%s'.
• 'chunk' filter argument 'size' must be a number. Actual type
• The 'escapeChar' filter expects the value of 'type' to be ei
• Too many rendering attempts

AI-assisted analysis of kestra-io/kestra@823fada927 (2026-08-14). Data as JSON: /api/errors/21ad64090d1d486b. Report an issue: GitHub.