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ontocast.onto.rdfgraph

RDFGraph

Bases: Graph

Subclass of rdflib.Graph with Pydantic schema support.

This class extends rdflib.Graph to provide serialization and deserialization capabilities for Pydantic models, with special handling for Turtle format.

Source code in ontocast/onto/rdfgraph.py
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class RDFGraph(Graph):
    """Subclass of rdflib.Graph with Pydantic schema support.

    This class extends rdflib.Graph to provide serialization and deserialization
    capabilities for Pydantic models, with special handling for Turtle format.
    """

    @classmethod
    def __get_pydantic_core_schema__(cls, _source_type, handler: GetCoreSchemaHandler):
        """Get the Pydantic core schema for this class.

        Args:
            _source_type: The source type.
            handler: The core schema handler.

        Returns:
            A union schema that handles both Graph instances and string conversion.
            Supports both Turtle and JSON-LD string formats.
        """
        return core_schema.union_schema(
            [
                core_schema.is_instance_schema(cls),
                core_schema.chain_schema(
                    [
                        core_schema.str_schema(),
                        core_schema.no_info_plain_validator_function(cls._from_str),
                    ]
                ),
            ],
            serialization=core_schema.plain_serializer_function_ser_schema(
                cls._to_turtle_str,
                info_arg=False,
                return_schema=core_schema.str_schema(),
            ),
        )

    def __add__(self, other: Union["RDFGraph", Graph, Iterable]) -> "RDFGraph":
        """Addition operator for RDFGraph instances.

        Merges the RDF graphs while maintaining the RDFGraph type.

        Args:
            other: The graph to add to this one.

        Returns:
            RDFGraph: A new RDFGraph containing the merged triples.
        """
        # Create a new RDFGraph instance
        result = RDFGraph()

        # Copy all triples from both graphs
        for triple in self:
            result.add(triple)
        for triple in other:
            result.add(triple)

        # Copy namespace bindings from self
        for prefix, uri in self.namespaces():
            result.bind(prefix, uri)

        # Copy namespace bindings from other if it's a Graph
        if isinstance(other, Graph):
            for prefix, uri in other.namespaces():
                result.bind(prefix, uri)

        return result

    def __iadd__(self, other: Union["RDFGraph", Graph, Iterable]) -> "RDFGraph":
        """In-place addition operator for RDFGraph instances.

        Merges the RDF graphs while maintaining the RDFGraph type and binding prefixes.

        Args:
            other: The graph to add to this one.

        Returns:
            RDFGraph: self after modification.
        """
        # Use __add__ to get the merged result with proper prefix binding
        result = self.__add__(other)

        # Clear current graph and copy the result
        self.remove((None, None, None))  # Remove all triples

        # Copy all triples from result
        for triple in result:
            self.add(triple)

        # Copy namespace bindings from result
        for prefix, uri in result.namespaces():
            self.bind(prefix, uri)

        return self

    def copy(self) -> "RDFGraph":
        """Create a copy of this RDFGraph.

        Returns:
            RDFGraph: A new RDFGraph instance with all triples and namespace bindings copied.
        """
        result = RDFGraph()

        # Copy all triples
        for triple in self:
            result.add(triple)

        # Copy namespace bindings
        for prefix, uri in self.namespaces():
            result.bind(prefix, uri)

        return result

    @staticmethod
    def _ensure_prefixes(turtle_str: str) -> str:
        """Ensure all common prefixes are declared in the Turtle string.

        Args:
            turtle_str: The input Turtle string.

        Returns:
            str: The Turtle string with all common prefixes declared.
        """
        declared_prefixes = set(
            match.group(1) for match in PREFIX_PATTERN.finditer(turtle_str)
        )

        missing = {
            prefix: uri
            for prefix, uri in COMMON_PREFIXES.items()
            if prefix not in declared_prefixes
        }

        if not missing:
            return turtle_str

        prefix_block = (
            "\n".join(f"@prefix {prefix}: {uri} ." for prefix, uri in missing.items())
            + "\n\n"
        )

        return prefix_block + turtle_str

    @staticmethod
    def _is_jsonld_str(s: str) -> bool:
        """Check if a string appears to be JSON-LD format.

        Args:
            s: The string to check.

        Returns:
            bool: True if the string appears to be JSON-LD.
        """
        s = s.strip()
        if not (s.startswith("{") or s.startswith("[")):
            return False
        try:
            # Try to parse as JSON
            data = json.loads(s)
            # Check if it's a dict/object with @context or @id, or an array containing such objects
            if isinstance(data, dict):
                return "@context" in data or "@id" in data
            elif isinstance(data, list):
                return any(
                    isinstance(item, dict) and ("@context" in item or "@id" in item)
                    for item in data
                )
            return False
        except (json.JSONDecodeError, ValueError):
            return False

    @classmethod
    def _from_str(cls, data_str: str) -> "RDFGraph":
        """Create an RDFGraph instance from a string (Turtle or JSON-LD).

        Automatically detects the format and parses accordingly.

        Args:
            data_str: The input string in Turtle or JSON-LD format.

        Returns:
            RDFGraph: A new RDFGraph instance.
        """
        if cls._is_jsonld_str(data_str):
            return cls._from_jsonld_str(data_str)
        else:
            return cls._from_turtle_str(data_str)

    @classmethod
    def _from_turtle_str(cls, turtle_str: str) -> "RDFGraph":
        """Create an RDFGraph instance from a Turtle string.

        Args:
            turtle_str: The input Turtle string.

        Returns:
            RDFGraph: A new RDFGraph instance.
        """
        turtle_str = bytes(turtle_str, "utf-8").decode("unicode_escape")
        patched_turtle = cls._ensure_prefixes(turtle_str)
        g = cls()
        g.parse(data=patched_turtle, format="turtle")
        return g

    @classmethod
    def _from_jsonld_str(cls, jsonld_str: str) -> "RDFGraph":
        """Create an RDFGraph instance from a JSON-LD string.

        Args:
            jsonld_str: The input JSON-LD string.

        Returns:
            RDFGraph: A new RDFGraph instance with namespace prefixes extracted from @context.
        """
        # Use pyld to convert JSON-LD to n-quads, then parse to avoid rdflib's deprecated ConjunctiveGraph
        # This adapts to the new convention by using pyld directly instead of rdflib's JSON-LD parser
        jsonld_data = json.loads(jsonld_str)
        normalized = jsonld.normalize(
            jsonld_data,
            {"algorithm": "URDNA2015", "format": "application/n-quads"},
        )

        # jsonld.normalize returns a string when format is "application/n-quads"
        normalized_str = normalized if isinstance(normalized, str) else str(normalized)

        # Parse the normalized n-quads into RDFGraph
        g = cls()
        g.parse(data=normalized_str, format="nquads")

        # Extract prefixes from @context in JSON-LD and bind them
        try:
            context = None

            # Handle single object or array
            if isinstance(jsonld_data, dict):
                context = jsonld_data.get("@context")
            elif isinstance(jsonld_data, list) and jsonld_data:
                # For arrays, check first item for @context
                first_item = jsonld_data[0]
                if isinstance(first_item, dict):
                    context = first_item.get("@context")

            # Bind prefixes from @context
            if context and isinstance(context, dict):
                for prefix, uri in context.items():
                    if isinstance(uri, str) and not prefix.startswith("@"):
                        # Skip JSON-LD keywords (starting with @)
                        try:
                            g.bind(prefix, uri)
                        except Exception as e:
                            logger.debug(f"Failed to bind prefix '{prefix}': {e}")

        except (json.JSONDecodeError, ValueError, AttributeError) as e:
            logger.debug(f"Could not extract prefixes from JSON-LD @context: {e}")

        return g

    @staticmethod
    def _to_turtle_str(g: Any) -> str:
        """Convert an RDFGraph to a Turtle string.

        Args:
            g: The RDFGraph instance.

        Returns:
            str: The Turtle string representation.
        """
        return g.serialize(format="turtle")

    def __new__(cls, *args, **kwargs):
        """Create a new RDFGraph instance."""
        instance = super().__new__(cls)
        return instance

    def sanitize_prefixes_namespaces(self):
        """
        Rematches prefixes in an RDFLib graph to correct namespaces when a namespace
        with the same URI exists. Handles cases where prefixes might not be bound
        as namespaces.

        Args:
            self (RDFGraph): The RDFLib graph to process

        Returns:
           RDFGraph: The graph with corrected prefix-namespace mappings
        """
        # Get the namespace manager
        ns_manager = self.namespace_manager

        # Collect all current prefix-URI mappings
        current_prefixes = dict(ns_manager.namespaces())

        # Group URIs by their string representation to find duplicates
        uri_to_prefixes = defaultdict(list)
        for prefix, uri in current_prefixes.items():
            uri_to_prefixes[str(uri)].append((prefix, uri))

        # Find the "canonical" namespace objects for each URI
        # (the actual Namespace objects that might be registered)
        canonical_namespaces = {}

        # Check if any of the URIs correspond to well-known namespaces
        # by trying to create Namespace objects and seeing if they're already registered
        for uri_str, prefix_uri_pairs in uri_to_prefixes.items():
            # Try to find if there's already a proper Namespace object for this URI
            namespace_candidates = []

            for prefix, uri_obj in prefix_uri_pairs:
                # Check if this is already a proper Namespace object
                if isinstance(uri_obj, Namespace):
                    namespace_candidates.append(uri_obj)
                else:
                    # Try to create a Namespace and see if it matches existing ones
                    try:
                        ns = Namespace(uri_str)
                        namespace_candidates.append(ns)
                    except:
                        continue

            # Use the first valid namespace candidate as canonical
            if namespace_candidates:
                canonical_namespaces[uri_str] = namespace_candidates[0]

        # Now rebuild the namespace manager with corrected mappings
        # Clear existing bindings first
        new_ns_manager = NamespaceManager(self)

        # Track which prefixes we want to keep/reassign
        final_mappings = {}

        for uri_str, prefix_uri_pairs in uri_to_prefixes.items():
            if len(prefix_uri_pairs) == 1:
                # No duplicates, keep as-is but ensure we use canonical namespace
                prefix, _ = prefix_uri_pairs[0]
                canonical_ns = canonical_namespaces.get(uri_str)
                if canonical_ns:
                    final_mappings[prefix] = canonical_ns
                else:
                    # Fallback to creating a new Namespace
                    final_mappings[prefix] = Namespace(uri_str)
            else:
                # Multiple prefixes for same URI - need to decide which to keep
                # Priority: 1) Proper Namespace objects,
                #           2) Shorter prefixes,
                #           3) Alphabetical
                prefix_uri_pairs.sort(
                    key=lambda x: (
                        not isinstance(x[1], Namespace),  # Namespace objects first
                        len(x[0]),  # Shorter prefixes next
                        x[0],  # Alphabetical order
                    )
                )

                # Keep the best prefix, map others to it if needed
                best_prefix, _ = prefix_uri_pairs[0]
                canonical_ns = canonical_namespaces.get(uri_str, Namespace(uri_str))
                final_mappings[best_prefix] = canonical_ns

                other_prefixes = [p for p, _ in prefix_uri_pairs[1:]]
                if other_prefixes:
                    logger.debug(
                        f"Consolidating prefixes {other_prefixes} "
                        f"-> '{best_prefix}' for URI: {uri_str}"
                    )

        # Apply the final mappings
        for prefix, namespace in final_mappings.items():
            new_ns_manager.bind(prefix, namespace, override=True)

        # Replace the graph's namespace manager
        self.namespace_manager = new_ns_manager

    def unbind_chunk_namespaces(self, chunk_pattern="/chunk/") -> "RDFGraph":
        """
        Unbinds namespace prefixes that point to URIs containing a chunk pattern.
        Returns a new graph with chunk namespaces dereferenced (expanded to full URIs).

        Args:
            chunk_pattern (str): The pattern to look for in URIs (default: "/chunk/")

        Returns:
            RDFGraph: New graph with chunk-related namespaces unbound
        """
        current_prefixes = dict(self.namespace_manager.namespaces())

        # Find prefixes that point to URIs containing the chunk pattern
        chunk_prefixes = []
        for prefix, uri in current_prefixes.items():
            uri_str = str(uri)
            if chunk_pattern in uri_str:
                chunk_prefixes.append((prefix, uri_str))

        # Create new graph
        new_graph = RDFGraph()

        # Copy all triples (URIs are already expanded internally)
        for triple in self:
            new_graph.add(triple)

        # Bind only non-chunk namespace prefixes to the new graph
        for prefix, uri in current_prefixes.items():
            uri_str = str(uri)
            if chunk_pattern not in uri_str:
                new_graph.bind(prefix, uri)

        # Log what was removed
        if chunk_prefixes:
            logger.debug(f"Unbound {len(chunk_prefixes)} chunk-related namespace(s):")
            for prefix, uri in chunk_prefixes:
                logger.debug(f"  - '{prefix}': {uri}")

        return new_graph

    def remap_namespaces(self, old_namespace, new_namespace) -> None:
        updates = {}
        for s, p, o in self:
            new_s, new_p, new_o = s, p, o
            if isinstance(s, URIRef) and str(s).startswith(str(old_namespace)):
                new_s = URIRef(
                    str(s).replace(str(old_namespace), str(new_namespace), 1)
                )
            if isinstance(p, URIRef) and str(p).startswith(str(old_namespace)):
                new_p = URIRef(
                    str(p).replace(str(old_namespace), str(new_namespace), 1)
                )
            if isinstance(o, URIRef) and str(o).startswith(str(old_namespace)):
                new_o = URIRef(
                    str(o).replace(str(old_namespace), str(new_namespace), 1)
                )

            if (new_s, new_p, new_o) != (s, p, o):
                updates[(s, p, o)] = (new_s, new_p, new_o)

        for (s, p, o), (new_s, new_p, new_o) in updates.items():
            self.remove((s, p, o))
            self.add((new_s, new_p, new_o))

    def add_triple(self, subject: str, predicate: str, object_: str) -> None:
        """Add a triple to the graph.

        Args:
            subject: Subject URI as string
            predicate: Predicate URI as string
            object_: Object URI as string or literal value
        """
        # Convert strings to appropriate RDFLib objects
        subj = URIRef(subject)
        pred = URIRef(predicate)

        # Handle object - could be URI or literal
        if object_.startswith("http://") or object_.startswith("https://"):
            obj = URIRef(object_)
        else:
            # Treat as literal
            obj = Literal(object_)

        self.add((subj, pred, obj))
        logger.debug(f"Added triple: {subj} {pred} {obj}")

    def remove_triple(self, subject: str, predicate: str, object_: str) -> None:
        """Remove a triple from the graph.

        Args:
            subject: Subject URI as string
            predicate: Predicate URI as string
            object_: Object URI as string or literal value
        """
        # Convert strings to appropriate RDFLib objects
        subj = URIRef(subject)
        pred = URIRef(predicate)

        # Handle object - could be URI or literal
        if object_.startswith("http://") or object_.startswith("https://"):
            obj = URIRef(object_)
        else:
            # Treat as literal
            obj = Literal(object_)

        self.remove((subj, pred, obj))
        logger.debug(f"Removed triple: {subj} {pred} {obj}")

    def hash(self: Graph) -> str:
        # Serialize to JSON-LD
        data = self.serialize(format="json-ld")

        # Parse the JSON string
        doc = json.loads(data)

        # Canonicalize using URDNA2015 normalization
        normalized = jsonld.normalize(
            doc,
            {"algorithm": "URDNA2015", "format": "application/n-quads"},
        )
        # jsonld.normalize returns a string when format is "application/n-quads"
        normalized_str = normalized if isinstance(normalized, str) else str(normalized)
        return hashlib.sha256(normalized_str.encode("utf-8")).hexdigest()

__add__(other)

Addition operator for RDFGraph instances.

Merges the RDF graphs while maintaining the RDFGraph type.

Parameters:

Name Type Description Default
other Union[RDFGraph, Graph, Iterable]

The graph to add to this one.

required

Returns:

Name Type Description
RDFGraph RDFGraph

A new RDFGraph containing the merged triples.

Source code in ontocast/onto/rdfgraph.py
def __add__(self, other: Union["RDFGraph", Graph, Iterable]) -> "RDFGraph":
    """Addition operator for RDFGraph instances.

    Merges the RDF graphs while maintaining the RDFGraph type.

    Args:
        other: The graph to add to this one.

    Returns:
        RDFGraph: A new RDFGraph containing the merged triples.
    """
    # Create a new RDFGraph instance
    result = RDFGraph()

    # Copy all triples from both graphs
    for triple in self:
        result.add(triple)
    for triple in other:
        result.add(triple)

    # Copy namespace bindings from self
    for prefix, uri in self.namespaces():
        result.bind(prefix, uri)

    # Copy namespace bindings from other if it's a Graph
    if isinstance(other, Graph):
        for prefix, uri in other.namespaces():
            result.bind(prefix, uri)

    return result

__get_pydantic_core_schema__(_source_type, handler) classmethod

Get the Pydantic core schema for this class.

Parameters:

Name Type Description Default
_source_type

The source type.

required
handler GetCoreSchemaHandler

The core schema handler.

required

Returns:

Type Description

A union schema that handles both Graph instances and string conversion.

Supports both Turtle and JSON-LD string formats.

Source code in ontocast/onto/rdfgraph.py
@classmethod
def __get_pydantic_core_schema__(cls, _source_type, handler: GetCoreSchemaHandler):
    """Get the Pydantic core schema for this class.

    Args:
        _source_type: The source type.
        handler: The core schema handler.

    Returns:
        A union schema that handles both Graph instances and string conversion.
        Supports both Turtle and JSON-LD string formats.
    """
    return core_schema.union_schema(
        [
            core_schema.is_instance_schema(cls),
            core_schema.chain_schema(
                [
                    core_schema.str_schema(),
                    core_schema.no_info_plain_validator_function(cls._from_str),
                ]
            ),
        ],
        serialization=core_schema.plain_serializer_function_ser_schema(
            cls._to_turtle_str,
            info_arg=False,
            return_schema=core_schema.str_schema(),
        ),
    )

__iadd__(other)

In-place addition operator for RDFGraph instances.

Merges the RDF graphs while maintaining the RDFGraph type and binding prefixes.

Parameters:

Name Type Description Default
other Union[RDFGraph, Graph, Iterable]

The graph to add to this one.

required

Returns:

Name Type Description
RDFGraph RDFGraph

self after modification.

Source code in ontocast/onto/rdfgraph.py
def __iadd__(self, other: Union["RDFGraph", Graph, Iterable]) -> "RDFGraph":
    """In-place addition operator for RDFGraph instances.

    Merges the RDF graphs while maintaining the RDFGraph type and binding prefixes.

    Args:
        other: The graph to add to this one.

    Returns:
        RDFGraph: self after modification.
    """
    # Use __add__ to get the merged result with proper prefix binding
    result = self.__add__(other)

    # Clear current graph and copy the result
    self.remove((None, None, None))  # Remove all triples

    # Copy all triples from result
    for triple in result:
        self.add(triple)

    # Copy namespace bindings from result
    for prefix, uri in result.namespaces():
        self.bind(prefix, uri)

    return self

__new__(*args, **kwargs)

Create a new RDFGraph instance.

Source code in ontocast/onto/rdfgraph.py
def __new__(cls, *args, **kwargs):
    """Create a new RDFGraph instance."""
    instance = super().__new__(cls)
    return instance

add_triple(subject, predicate, object_)

Add a triple to the graph.

Parameters:

Name Type Description Default
subject str

Subject URI as string

required
predicate str

Predicate URI as string

required
object_ str

Object URI as string or literal value

required
Source code in ontocast/onto/rdfgraph.py
def add_triple(self, subject: str, predicate: str, object_: str) -> None:
    """Add a triple to the graph.

    Args:
        subject: Subject URI as string
        predicate: Predicate URI as string
        object_: Object URI as string or literal value
    """
    # Convert strings to appropriate RDFLib objects
    subj = URIRef(subject)
    pred = URIRef(predicate)

    # Handle object - could be URI or literal
    if object_.startswith("http://") or object_.startswith("https://"):
        obj = URIRef(object_)
    else:
        # Treat as literal
        obj = Literal(object_)

    self.add((subj, pred, obj))
    logger.debug(f"Added triple: {subj} {pred} {obj}")

copy()

Create a copy of this RDFGraph.

Returns:

Name Type Description
RDFGraph RDFGraph

A new RDFGraph instance with all triples and namespace bindings copied.

Source code in ontocast/onto/rdfgraph.py
def copy(self) -> "RDFGraph":
    """Create a copy of this RDFGraph.

    Returns:
        RDFGraph: A new RDFGraph instance with all triples and namespace bindings copied.
    """
    result = RDFGraph()

    # Copy all triples
    for triple in self:
        result.add(triple)

    # Copy namespace bindings
    for prefix, uri in self.namespaces():
        result.bind(prefix, uri)

    return result

remove_triple(subject, predicate, object_)

Remove a triple from the graph.

Parameters:

Name Type Description Default
subject str

Subject URI as string

required
predicate str

Predicate URI as string

required
object_ str

Object URI as string or literal value

required
Source code in ontocast/onto/rdfgraph.py
def remove_triple(self, subject: str, predicate: str, object_: str) -> None:
    """Remove a triple from the graph.

    Args:
        subject: Subject URI as string
        predicate: Predicate URI as string
        object_: Object URI as string or literal value
    """
    # Convert strings to appropriate RDFLib objects
    subj = URIRef(subject)
    pred = URIRef(predicate)

    # Handle object - could be URI or literal
    if object_.startswith("http://") or object_.startswith("https://"):
        obj = URIRef(object_)
    else:
        # Treat as literal
        obj = Literal(object_)

    self.remove((subj, pred, obj))
    logger.debug(f"Removed triple: {subj} {pred} {obj}")

sanitize_prefixes_namespaces()

Rematches prefixes in an RDFLib graph to correct namespaces when a namespace with the same URI exists. Handles cases where prefixes might not be bound as namespaces.

Parameters:

Name Type Description Default
self RDFGraph

The RDFLib graph to process

required

Returns:

Name Type Description
RDFGraph

The graph with corrected prefix-namespace mappings

Source code in ontocast/onto/rdfgraph.py
def sanitize_prefixes_namespaces(self):
    """
    Rematches prefixes in an RDFLib graph to correct namespaces when a namespace
    with the same URI exists. Handles cases where prefixes might not be bound
    as namespaces.

    Args:
        self (RDFGraph): The RDFLib graph to process

    Returns:
       RDFGraph: The graph with corrected prefix-namespace mappings
    """
    # Get the namespace manager
    ns_manager = self.namespace_manager

    # Collect all current prefix-URI mappings
    current_prefixes = dict(ns_manager.namespaces())

    # Group URIs by their string representation to find duplicates
    uri_to_prefixes = defaultdict(list)
    for prefix, uri in current_prefixes.items():
        uri_to_prefixes[str(uri)].append((prefix, uri))

    # Find the "canonical" namespace objects for each URI
    # (the actual Namespace objects that might be registered)
    canonical_namespaces = {}

    # Check if any of the URIs correspond to well-known namespaces
    # by trying to create Namespace objects and seeing if they're already registered
    for uri_str, prefix_uri_pairs in uri_to_prefixes.items():
        # Try to find if there's already a proper Namespace object for this URI
        namespace_candidates = []

        for prefix, uri_obj in prefix_uri_pairs:
            # Check if this is already a proper Namespace object
            if isinstance(uri_obj, Namespace):
                namespace_candidates.append(uri_obj)
            else:
                # Try to create a Namespace and see if it matches existing ones
                try:
                    ns = Namespace(uri_str)
                    namespace_candidates.append(ns)
                except:
                    continue

        # Use the first valid namespace candidate as canonical
        if namespace_candidates:
            canonical_namespaces[uri_str] = namespace_candidates[0]

    # Now rebuild the namespace manager with corrected mappings
    # Clear existing bindings first
    new_ns_manager = NamespaceManager(self)

    # Track which prefixes we want to keep/reassign
    final_mappings = {}

    for uri_str, prefix_uri_pairs in uri_to_prefixes.items():
        if len(prefix_uri_pairs) == 1:
            # No duplicates, keep as-is but ensure we use canonical namespace
            prefix, _ = prefix_uri_pairs[0]
            canonical_ns = canonical_namespaces.get(uri_str)
            if canonical_ns:
                final_mappings[prefix] = canonical_ns
            else:
                # Fallback to creating a new Namespace
                final_mappings[prefix] = Namespace(uri_str)
        else:
            # Multiple prefixes for same URI - need to decide which to keep
            # Priority: 1) Proper Namespace objects,
            #           2) Shorter prefixes,
            #           3) Alphabetical
            prefix_uri_pairs.sort(
                key=lambda x: (
                    not isinstance(x[1], Namespace),  # Namespace objects first
                    len(x[0]),  # Shorter prefixes next
                    x[0],  # Alphabetical order
                )
            )

            # Keep the best prefix, map others to it if needed
            best_prefix, _ = prefix_uri_pairs[0]
            canonical_ns = canonical_namespaces.get(uri_str, Namespace(uri_str))
            final_mappings[best_prefix] = canonical_ns

            other_prefixes = [p for p, _ in prefix_uri_pairs[1:]]
            if other_prefixes:
                logger.debug(
                    f"Consolidating prefixes {other_prefixes} "
                    f"-> '{best_prefix}' for URI: {uri_str}"
                )

    # Apply the final mappings
    for prefix, namespace in final_mappings.items():
        new_ns_manager.bind(prefix, namespace, override=True)

    # Replace the graph's namespace manager
    self.namespace_manager = new_ns_manager

unbind_chunk_namespaces(chunk_pattern='/chunk/')

Unbinds namespace prefixes that point to URIs containing a chunk pattern. Returns a new graph with chunk namespaces dereferenced (expanded to full URIs).

Parameters:

Name Type Description Default
chunk_pattern str

The pattern to look for in URIs (default: "/chunk/")

'/chunk/'

Returns:

Name Type Description
RDFGraph RDFGraph

New graph with chunk-related namespaces unbound

Source code in ontocast/onto/rdfgraph.py
def unbind_chunk_namespaces(self, chunk_pattern="/chunk/") -> "RDFGraph":
    """
    Unbinds namespace prefixes that point to URIs containing a chunk pattern.
    Returns a new graph with chunk namespaces dereferenced (expanded to full URIs).

    Args:
        chunk_pattern (str): The pattern to look for in URIs (default: "/chunk/")

    Returns:
        RDFGraph: New graph with chunk-related namespaces unbound
    """
    current_prefixes = dict(self.namespace_manager.namespaces())

    # Find prefixes that point to URIs containing the chunk pattern
    chunk_prefixes = []
    for prefix, uri in current_prefixes.items():
        uri_str = str(uri)
        if chunk_pattern in uri_str:
            chunk_prefixes.append((prefix, uri_str))

    # Create new graph
    new_graph = RDFGraph()

    # Copy all triples (URIs are already expanded internally)
    for triple in self:
        new_graph.add(triple)

    # Bind only non-chunk namespace prefixes to the new graph
    for prefix, uri in current_prefixes.items():
        uri_str = str(uri)
        if chunk_pattern not in uri_str:
            new_graph.bind(prefix, uri)

    # Log what was removed
    if chunk_prefixes:
        logger.debug(f"Unbound {len(chunk_prefixes)} chunk-related namespace(s):")
        for prefix, uri in chunk_prefixes:
            logger.debug(f"  - '{prefix}': {uri}")

    return new_graph