YAML Functions

The YAML module provides functions for parsing, processing, and converting YAML (YAML Ain’t Markup Language) data.

Including the YAML Module

To use the YAML functions, include the module at the top of your mq script:

include "yaml"

Functions

yaml_parse(input)

Parses a YAML string and returns the parsed data structure.

Parameters:

• input: String containing the YAML data

Returns:

• Parsed data structure (dict, array, or scalar value depending on the YAML content)

Example:

include "yaml"

# Parse YAML object
| "name: John\nage: 30\ncity: New York" | yaml_parse()
# Returns: {"name": "John", "age": 30, "city": "New York"}

# Parse YAML array
| "- item1\n- item2\n- item3" | yaml_parse()
# Returns: ["item1", "item2", "item3"]

# Parse complex YAML
| "users:\n  - name: John\n    age: 30\n  - name: Jane\n    age: 25" | yaml_parse()
# Returns: {"users": [{"name": "John", "age": 30}, {"name": "Jane", "age": 25}]}

yaml_stringify(data)

Converts a data structure to a YAML string representation.

Parameters:

• data: Data structure to convert (dict, array, or scalar value)

Returns:

• String containing the formatted YAML data

Example:

include "yaml"

# Convert dict to YAML
| {"name": "John", "age": 30, "city": "New York"} | yaml_stringify()
# Returns: "name: John\nage: 30\ncity: New York"

# Convert array to YAML
| ["item1", "item2", "item3"] | yaml_stringify()
# Returns: "- item1\n- item2\n- item3"

# Convert nested structure to YAML
| {"users": [{"name": "John", "age": 30}, {"name": "Jane", "age": 25}]} | yaml_stringify()
# Returns: "users:\n  - name: John\n    age: 30\n  - name: Jane\n    age: 25"

yaml_keys(data, prefix)

Returns all keys in a YAML data structure, including nested keys, with dot notation.

Parameters:

• data: YAML data structure (dict or array)
• prefix: String prefix to add to the keys (use empty string for no prefix)

Returns:

• Array of strings containing all keys with dot notation for nested structures

Example:

include "yaml"

# Get keys from nested YAML structure
| let data = {"user": {"name": "John", "profile": {"age": 30, "city": "New York"}}}
| data | yaml_keys("")
# Returns: ["user", "user.name", "user.profile", "user.profile.age", "user.profile.city"]

# Get keys with prefix
| data | yaml_keys("root")
# Returns: ["root.user", "root.user.name", "root.user.profile", "root.user.profile.age", "root.user.profile.city"]

yaml_to_json(data)

Converts a YAML data structure to a JSON string representation.

Parameters:

• data: YAML data structure to convert

Returns:

• String containing the JSON representation

Example:

include "yaml"

# Convert YAML data to JSON
| {"name": "John", "age": 30, "active": true} | yaml_to_json()
# Returns: "{\"name\": \"John\", \"age\": 30, \"active\": true}"

# Convert array to JSON
| ["item1", "item2", "item3"] | yaml_to_json()
# Returns: "[\"item1\", \"item2\", \"item3\"]"

yaml_to_markdown_table(data)

Converts a YAML data structure to a Markdown table format.

Parameters:

• data: YAML data structure to convert (dict, array, or scalar value)

Returns:

• String containing the Markdown table

Example:

include "yaml"

# Convert dict to Markdown table
| {"name": "John", "age": 30, "city": "New York"} | yaml_to_markdown_table()
# Returns:
# | Key | Value |
# | --- | --- |
# | name | John |
# | age | 30 |
# | city | New York |

# Convert array of dicts to Markdown table
| [{"name": "John", "age": 30}, {"name": "Jane", "age": 25}] | yaml_to_markdown_table()
# Returns:
# | name | age |
# | --- | --- |
# | John | 30 |
# | Jane | 25 |

YAML Format Support

The YAML parser supports YAML 1.2 specifications and handles:

• Scalars: strings, numbers, booleans, and null values
• Collections: sequences (arrays) and mappings (dictionaries)
• Nested structures with proper indentation
• Quoted and unquoted strings
• Multi-line strings with literal block scalars (|)
• Boolean values: true, false, yes, no (case-insensitive)
• Null values: null, ~, or empty values
• Comments (lines starting with #)
• Proper handling of special characters and escape sequences

Type Conversion

The YAML parser automatically converts values to appropriate types:

• Strings: Quoted or unquoted text
• Numbers: Integers and floating-point numbers
• Booleans: true/false, yes/no, True/False, etc.
• Null: null, ~, or empty values become None
• Arrays: YAML sequences become mq arrays
• Objects: YAML mappings become mq dictionaries