Minify

Mutate Content Optimization

Synopsis

A content optimization processor that minifies XML, JSON, and HTML documents by removing unnecessary whitespace, comments, and other non-essential elements to reduce file size and improve performance.

Schema

- minify:
    field: <ident>
    format: <enum>
    target_field: <ident>
    keep_whitespace: <boolean>
    keep_comments: <boolean>
    description: <text>
    if: <script>
    ignore_failure: <boolean>
    ignore_missing: <boolean>
    keep_end_tags: <boolean>
    keep_document_tags: <boolean>
    on_failure: <processor[]>
    on_success: <processor[]>
    tag: <string>

Configuration

The following fields are used to define the processor:

Field	Required	Default	Description
field	Y	-	Field containing the content to minify
format	Y	-	Content format: xml, json, or html. Any other value fails the processor
target_field	N	field	Field to store the minified content
keep_whitespace	N	false	Preserve whitespace. XML and HTML only; JSON ignores it
keep_comments	N	false	Preserve comments. HTML only — it also covers conditional comments. XML and JSON ignore it, and XML comments are always stripped
keep_end_tags	N	false	Preserve end tags in HTML (HTML only)
keep_document_tags	N	false	Preserve document tags in HTML (HTML only)
description	N	-	Explanatory note
if	N	-	Condition to run
ignore_failure	N	false	Continue if minification fails
ignore_missing	N	false	Continue if source field doesn't exist
on_failure	N	-	See Handling Failures
on_success	N	-	See Handling Success
tag	N	-	Identifier
disabled	N	false	When true, the processor is skipped and the event continues to the next one. Lets you take a processor out of the path without removing its configuration

Details

The processor provides content minification for three primary formats: XML, JSON, and HTML. Each format has specific optimization strategies tailored to its structure and common use cases.

note

Minification is irreversible - ensure you preserve original content if needed.

XML minification removes whitespace between elements and always removes comments. keep_comments applies to HTML only. JSON compaction keeps number types, never writes a number in scientific notation, and takes no options. HTML is the only format that honours the full option set.

keep_end_tags, keep_document_tags and keep_comments reach the HTML minifier only. keep_whitespace reaches XML and HTML. Setting an option on a format that ignores it is silent, not an error.

warning

Test minified content thoroughly as some applications may depend on specific formatting.

Examples

XML Minification

Minifying XML content...	{ "xml_data": "<?xml version=\"1.0\"?>\n<root>\n <item>value</item>\n <!-- comment -->\n</root>" } - minify: field: xml_data format: xml target_field: minified_xml
produces compact XML:	{ "xml_data": "<?xml version=\"1.0\"?>\n<root>\n <item>value</item>\n <!-- comment -->\n</root>", "minified_xml": "<?xml version=\"1.0\"?><root><item>value</item></root>" }

JSON Minification

Compacting JSON data...	{ "json_content": "{\n \"name\": \"example\",\n \"value\": 123,\n \"nested\": {\n \"key\": \"data\"\n }\n}" } - minify: field: json_content format: json
removes all formatting:	{ "json_content": "{\"name\":\"example\",\"value\":123,\"nested\":{\"key\":\"data\"}}" }

HTML Minification

Optimizing HTML content...	{ "html_page": "<!DOCTYPE html>\n<html>\n <head>\n <title>Example</title>\n </head>\n <body>\n <!-- Main content -->\n <div class=\"container\">\n <p>Hello World</p>\n </div>\n </body>\n</html>" } - minify: field: html_page format: html target_field: optimized_html
creates compact HTML:	{ "html_page": "<!DOCTYPE html>\n<html>\n <head>\n <title>Example</title>\n </head>\n <body>\n <!-- Main content -->\n <div class=\"container\">\n <p>Hello World</p>\n </div>\n </body>\n</html>", "optimized_html": "<!doctype html><html><head><title>Example</title><body><div class=container><p>Hello World" }

Preserving Comments in HTML

keep_comments works for HTML only...	{ "page": "<html>\n <!-- Important setting -->\n <body>value</body>\n</html>" } - minify: field: page format: html keep_comments: true keep_whitespace: false
keeps the comment while removing the layout whitespace — the same configuration with format: xml would strip it:	{ "page": "<html><!-- Important setting --><body>value</body></html>" }

Conditional Minification

Minifying based on content size...	{ "large_json": "{\n \"data\": \"large content here\"\n}", "content_size": 1024 } - minify: field: large_json format: json if: "content_size > 500" target_field: compressed_json
applies minification when needed:	{ "large_json": "{\n \"data\": \"large content here\"\n}", "content_size": 1024, "compressed_json": "{\"data\":\"large content here\"}" }

HTML with Preserved Structure

Minifying HTML while keeping structure...	{ "template": "<html>\n<head></head>\n<body>\n <main>Content</main>\n</body>\n</html>" } - minify: field: template format: html keep_end_tags: true keep_document_tags: true target_field: clean_template
maintains essential HTML structure:	{ "template": "<html>\n<head></head>\n<body>\n <main>Content</main>\n</body>\n</html>", "clean_template": "<html><head></head><body><main>Content</main></body></html>" }