Detector

detector

Format detection via parse-based heuristics.

Format

Bases: Enum

Supported input formats.

Source code in packages/axm-smelt/src/axm_smelt/core/models.py

class Format(enum.Enum):
    """Supported input formats."""

    JSON = "json"
    YAML = "yaml"
    XML = "xml"
    TOML = "toml"
    CSV = "csv"
    MARKDOWN = "markdown"
    TEXT = "text"

detect_format(text)

Detect the format of text using parse-based heuristics.

Source code in packages/axm-smelt/src/axm_smelt/core/detector.py

def detect_format(text: str) -> Format:
    """Detect the format of *text* using parse-based heuristics."""
    fmt, _ = detect_format_parsed(text)
    return fmt

detect_format_parsed(text)

Detect format and return (format, parsed_data).

parsed_data is non-None only when the format is JSON, giving the caller the already-parsed object so it can be injected into a :class:SmeltContext without a redundant json.loads call.

Source code in packages/axm-smelt/src/axm_smelt/core/detector.py

def detect_format_parsed(text: str) -> tuple[Format, object | None]:
    """Detect format and return ``(format, parsed_data)``.

    *parsed_data* is non-None only when the format is JSON, giving the
    caller the already-parsed object so it can be injected into a
    :class:`SmeltContext` without a redundant ``json.loads`` call.
    """
    stripped = text.strip()
    if not stripped:
        return Format.TEXT, None

    # JSON probe — capture the parsed object
    if stripped[0] in ("{", "["):
        try:
            data = json.loads(stripped)
            return Format.JSON, data
        except (json.JSONDecodeError, ValueError):
            pass

    # Remaining probes (XML, YAML, Markdown) — no parsed data
    for probe in (try_xml, try_yaml, try_markdown):
        result = probe(stripped)
        if result is not None:
            return result, None

    return Format.TEXT, None

try_json(stripped)

Return Format.JSON if stripped is valid JSON, else None.

Source code in packages/axm-smelt/src/axm_smelt/core/detector.py

def try_json(stripped: str) -> Format | None:
    """Return ``Format.JSON`` if *stripped* is valid JSON, else ``None``."""
    if stripped[0] in ("{", "["):
        try:
            json.loads(stripped)
            return Format.JSON
        except (json.JSONDecodeError, ValueError):
            pass
    return None

try_markdown(stripped)

Return Format.MARKDOWN if stripped has >=2 distinct markdown indicators.

Source code in packages/axm-smelt/src/axm_smelt/core/detector.py

def try_markdown(stripped: str) -> Format | None:
    """Return ``Format.MARKDOWN`` if *stripped* has >=2 distinct markdown indicators."""
    indicators = 0
    heading_levels = {len(m.group().rstrip()) for m in _MD_HEADING.finditer(stripped)}
    if len(heading_levels) >= 2:  # noqa: PLR2004
        indicators += 2
    elif heading_levels:
        indicators += 1
    if _MD_TABLE_SEP.search(stripped) and _MD_TABLE_DASH.search(stripped):
        indicators += 2  # pipe table with separator is a strong signal
    if len(_MD_FENCED.findall(stripped)) >= 2:  # noqa: PLR2004
        indicators += 1
    if _MD_LINK.search(stripped):
        indicators += 1
    if indicators >= 2:  # noqa: PLR2004
        return Format.MARKDOWN
    return None

try_xml(stripped)

Return Format.XML if stripped looks like XML, else None.

Source code in packages/axm-smelt/src/axm_smelt/core/detector.py

def try_xml(stripped: str) -> Format | None:
    """Return ``Format.XML`` if *stripped* looks like XML, else ``None``."""
    if stripped.startswith("<") and not stripped.startswith("<!"):
        # XML declaration is a strong signal
        if stripped.startswith("<?xml"):
            return Format.XML
        match = re.match(r"<(\w+)[\s>]", stripped)
        if match and re.search(r"<\w+[^>]*>", stripped):
            root_tag = match.group(1).lower()
            if root_tag not in _HTML_TAGS:
                return Format.XML
    return None

try_yaml(stripped)

Return Format.YAML if stripped has YAML indicators, else None.

Source code in packages/axm-smelt/src/axm_smelt/core/detector.py

def try_yaml(stripped: str) -> Format | None:
    """Return ``Format.YAML`` if *stripped* has YAML indicators, else ``None``."""
    if _YAML_INDICATORS.search(stripped):
        try:
            result = yaml.safe_load(stripped)
            if isinstance(result, (dict, list)):
                return Format.YAML
        except yaml.YAMLError:
            pass
    return None