markdown_processor

trestle.core.markdown.markdown_processor

A markdown processor.

logger

Classes

MarkdownProcessor

A markdown processor.

Source code in trestle/core/markdown/markdown_processor.py

class MarkdownProcessor:
    """A markdown processor."""

    def __init__(self) -> None:
        """Initialize markdown processor."""
        self.governed_header = None

    def render_gfm_to_html(self, markdown_text: str) -> str:
        """Render given Github Flavored Markdown to HTML."""
        try:
            html = cmarkgfm.github_flavored_markdown_to_html(markdown_text)
            return html
        except ValueError as e:
            raise TrestleError(f'Not a valid Github Flavored markdown: {e}.')

    def process_markdown(self, md_path: pathlib.Path) -> Tuple[Dict, MarkdownNode]:
        """Parse the markdown and builds the tree to operate over it."""
        header, markdown_wo_header = self.read_markdown_wo_processing(md_path)

        _ = self.render_gfm_to_html(markdown_wo_header)

        lines = markdown_wo_header.split('\n')
        tree = MarkdownNode.build_tree_from_markdown(lines, self.governed_header)
        return header, tree

    def read_markdown_wo_processing(self, md_path: pathlib.Path) -> Tuple[Dict, str]:
        """Read markdown header to dictionary and body to string."""
        try:
            contents = frontmatter.loads(md_path.open('r', encoding=const.FILE_ENCODING).read())
            header = contents.metadata
            markdown_wo_header = contents.content

            return header, markdown_wo_header
        except UnicodeDecodeError as e:
            logger.debug(traceback.format_exc())
            raise TrestleError(f'Markdown cannot be decoded into {const.FILE_ENCODING}, error: {e}')
        except ScannerError as e:
            logger.debug(traceback.format_exc())
            raise TrestleError(f'Header is not in a valid YAML format: {e}')
        except FileNotFoundError as e:
            logger.debug(traceback.format_exc())
            raise TrestleError(f'Markdown with path {md_path}, not found: {e}')

    def fetch_value_from_header(self, md_path: pathlib.Path, key: str) -> Optional[str]:
        """Fetch value for the given key from the markdown header if exists."""
        header, _ = self.read_markdown_wo_processing(md_path)
        value = None

        if key in header.keys():
            value = header[key]

        return value

Methods

__init__(self) special

Initialize markdown processor.

Source code in trestle/core/markdown/markdown_processor.py

def __init__(self) -> None:
    """Initialize markdown processor."""
    self.governed_header = None

fetch_value_from_header(self, md_path, key)

Fetch value for the given key from the markdown header if exists.

Source code in trestle/core/markdown/markdown_processor.py

def fetch_value_from_header(self, md_path: pathlib.Path, key: str) -> Optional[str]:
    """Fetch value for the given key from the markdown header if exists."""
    header, _ = self.read_markdown_wo_processing(md_path)
    value = None

    if key in header.keys():
        value = header[key]

    return value

process_markdown(self, md_path)

Parse the markdown and builds the tree to operate over it.

Source code in trestle/core/markdown/markdown_processor.py

def process_markdown(self, md_path: pathlib.Path) -> Tuple[Dict, MarkdownNode]:
    """Parse the markdown and builds the tree to operate over it."""
    header, markdown_wo_header = self.read_markdown_wo_processing(md_path)

    _ = self.render_gfm_to_html(markdown_wo_header)

    lines = markdown_wo_header.split('\n')
    tree = MarkdownNode.build_tree_from_markdown(lines, self.governed_header)
    return header, tree

read_markdown_wo_processing(self, md_path)

Read markdown header to dictionary and body to string.

Source code in trestle/core/markdown/markdown_processor.py

def read_markdown_wo_processing(self, md_path: pathlib.Path) -> Tuple[Dict, str]:
    """Read markdown header to dictionary and body to string."""
    try:
        contents = frontmatter.loads(md_path.open('r', encoding=const.FILE_ENCODING).read())
        header = contents.metadata
        markdown_wo_header = contents.content

        return header, markdown_wo_header
    except UnicodeDecodeError as e:
        logger.debug(traceback.format_exc())
        raise TrestleError(f'Markdown cannot be decoded into {const.FILE_ENCODING}, error: {e}')
    except ScannerError as e:
        logger.debug(traceback.format_exc())
        raise TrestleError(f'Header is not in a valid YAML format: {e}')
    except FileNotFoundError as e:
        logger.debug(traceback.format_exc())
        raise TrestleError(f'Markdown with path {md_path}, not found: {e}')

render_gfm_to_html(self, markdown_text)

Render given Github Flavored Markdown to HTML.

Source code in trestle/core/markdown/markdown_processor.py

def render_gfm_to_html(self, markdown_text: str) -> str:
    """Render given Github Flavored Markdown to HTML."""
    try:
        html = cmarkgfm.github_flavored_markdown_to_html(markdown_text)
        return html
    except ValueError as e:
        raise TrestleError(f'Not a valid Github Flavored markdown: {e}.')

handler: python