Class SaneYAMLHandler

src/licensedcode/frontmatter.py:25–84

Load and export YAML metadata. . This is similar to the original frontmatter.default_handlers.YAMLHandler but is using nexB/saneyaml instead of pyyaml.

class SaneYAMLHandler:
    """
    Load and export YAML metadata. .

    This is similar to the original frontmatter.default_handlers.YAMLHandler
    but is using nexB/saneyaml instead of pyyaml.
    """
    FM_BOUNDARY = re.compile(r"^-{3,}\s*$", re.MULTILINE)
    START_DELIMITER = END_DELIMITER = "---"

    def __init__(self):
        self.FM_BOUNDARY = self.FM_BOUNDARY
        self.START_DELIMITER = self.START_DELIMITER
        self.END_DELIMITER = self.END_DELIMITER

    def detect(self, text):
        """
        Decide whether this handler can parse the given ``text``,
        and return True or False.
        """
        if self.FM_BOUNDARY.match(text):
            return True
        return False

    def split(self, text):
        """
        Split text into frontmatter and content.
        """
        _, fm, content = self.FM_BOUNDARY.split(text, 2)
        return fm, content

    def format(self, content, metadata, template=DEFAULT_POST_TEMPLATE, **kwargs):
        """
        Return string with `content` and `metadata` as YAML frontmatter,
        used in ``frontmatter.dumps``.
        """
        start_delimiter = kwargs.pop("start_delimiter", self.START_DELIMITER)
        end_delimiter = kwargs.pop("end_delimiter", self.END_DELIMITER)

        metadata = self.export(metadata, **kwargs)

        return template.format(
            metadata=metadata,
            content=content,
            start_delimiter=start_delimiter,
            end_delimiter=end_delimiter,
        ).strip()

    def load(self, fm, **kwargs):
        """
        Parse YAML front matter.
        """
        return saneyaml.load(fm, allow_duplicate_keys=False, **kwargs)

    def export(self, metadata, **kwargs):
        """
        Export metadata as YAML.
        """