Classification

arkindex_worker.worker.classification

ElementsWorker methods for classifications and ML classes.

load_corpus_classes

load_corpus_classes()

Load all ML classes available in the worker’s corpus and store them in the self.classes cache.

Source code in arkindex_worker/worker/classification.py

def load_corpus_classes(self):
    """
    Load all ML classes available in the worker's corpus and store them in the ``self.classes`` cache.
    """
    corpus_classes = self.api_client.paginate(
        "ListCorpusMLClasses",
        id=self.corpus_id,
    )
    self.classes = {ml_class["name"]: ml_class["id"] for ml_class in corpus_classes}
    logger.info(
        f"Loaded {len(self.classes)} ML classes in corpus ({self.corpus_id})"
    )

get_ml_class_id

get_ml_class_id(ml_class)

Return the MLClass ID corresponding to the given class name on a specific corpus.

If no MLClass exists for this class name, a new one is created.

Parameters:

Name	Type	Description	Default
ml_class	str	Name of the MLClass.	required

Returns:

Type	Description
str	ID of the retrieved or created MLClass.

Source code in arkindex_worker/worker/classification.py

def get_ml_class_id(self, ml_class: str) -> str:
    """
    Return the MLClass ID corresponding to the given class name on a specific corpus.

    If no MLClass exists for this class name, a new one is created.
    :param ml_class: Name of the MLClass.
    :returns: ID of the retrieved or created MLClass.
    """
    if not self.classes:
        self.load_corpus_classes()

    ml_class_id = self.classes.get(ml_class)
    if ml_class_id is None:
        logger.info(f"Creating ML class {ml_class} on corpus {self.corpus_id}")
        try:
            response = self.request(
                "CreateMLClass", id=self.corpus_id, body={"name": ml_class}
            )
            ml_class_id = self.classes[ml_class] = response["id"]
            logger.debug(f"Created ML class {response['id']}")
        except ErrorResponse as e:
            # Only reload for 400 errors
            if e.status_code != 400:
                raise

            # Reload and make sure we have the class
            logger.info(
                f"Reloading corpus classes to see if {ml_class} already exists"
            )
            self.load_corpus_classes()
            assert (
                ml_class in self.classes
            ), "Missing class {ml_class} even after reloading"
            ml_class_id = self.classes[ml_class]

    return ml_class_id

retrieve_ml_class

retrieve_ml_class(ml_class_id)

Retrieve the name of the MLClass from its ID.

Parameters:

Name	Type	Description	Default
ml_class_id	str	ID of the searched MLClass.	required

Returns:

Type	Description
str	The MLClass’s name

Source code in arkindex_worker/worker/classification.py

def retrieve_ml_class(self, ml_class_id: str) -> str:
    """
    Retrieve the name of the MLClass from its ID.

    :param ml_class_id: ID of the searched MLClass.
    :return: The MLClass's name
    """
    # Load the corpus' MLclasses if they are not available yet
    if not self.classes:
        self.load_corpus_classes()

    # Filter classes by this ml_class_id
    ml_class_name = next(
        filter(
            lambda x: self.classes[x] == ml_class_id,
            self.classes,
        ),
        None,
    )
    assert (
        ml_class_name is not None
    ), f"Missing class with id ({ml_class_id}) in corpus ({self.corpus_id})"
    return ml_class_name

create_classification

create_classification(
    element, ml_class, confidence, high_confidence=False
)

Create a classification on the given element through the API.

Parameters:

Name	Type	Description	Default
element	Union[Element, CachedElement]	The element to create a classification on.	required
ml_class	str	Name of the MLClass to use.	required
confidence	float	Confidence score for the classification. Must be between 0 and 1.	required
high_confidence	Optional[bool]	Whether or not the classification is of high confidence.	False

Returns:

Type	Description
Dict[str, str]	The created classification, as returned by the CreateClassification API endpoint.

Source code in arkindex_worker/worker/classification.py

def create_classification(
    self,
    element: Union[Element, CachedElement],
    ml_class: str,
    confidence: float,
    high_confidence: Optional[bool] = False,
) -> Dict[str, str]:
    """
    Create a classification on the given element through the API.

    :param element: The element to create a classification on.
    :param ml_class: Name of the MLClass to use.
    :param confidence: Confidence score for the classification. Must be between 0 and 1.
    :param high_confidence: Whether or not the classification is of high confidence.
    :returns: The created classification, as returned by the ``CreateClassification`` API endpoint.
    """
    assert element and isinstance(
        element, (Element, CachedElement)
    ), "element shouldn't be null and should be an Element or CachedElement"
    assert ml_class and isinstance(
        ml_class, str
    ), "ml_class shouldn't be null and should be of type str"
    assert (
        isinstance(confidence, float) and 0 <= confidence <= 1
    ), "confidence shouldn't be null and should be a float in [0..1] range"
    assert isinstance(
        high_confidence, bool
    ), "high_confidence shouldn't be null and should be of type bool"
    if self.is_read_only:
        logger.warning(
            "Cannot create classification as this worker is in read-only mode"
        )
        return
    try:
        created = self.request(
            "CreateClassification",
            body={
                "element": str(element.id),
                "ml_class": self.get_ml_class_id(ml_class),
                "worker_run_id": self.worker_run_id,
                "confidence": confidence,
                "high_confidence": high_confidence,
            },
        )

        if self.use_cache:
            # Store classification in local cache
            try:
                to_insert = [
                    {
                        "id": created["id"],
                        "element_id": element.id,
                        "class_name": ml_class,
                        "confidence": created["confidence"],
                        "state": created["state"],
                        "worker_run_id": self.worker_run_id,
                    }
                ]
                CachedClassification.insert_many(to_insert).execute()
            except IntegrityError as e:
                logger.warning(
                    f"Couldn't save created classification in local cache: {e}"
                )
    except ErrorResponse as e:
        # Detect already existing classification
        if e.status_code == 400 and "non_field_errors" in e.content:
            if (
                "The fields element, worker_version, ml_class must make a unique set."
                in e.content["non_field_errors"]
            ):
                logger.warning(
                    f"This worker version has already set {ml_class} on element {element.id}"
                )
            elif (
                "The fields element, worker_run, ml_class must make a unique set."
                in e.content["non_field_errors"]
            ):
                logger.warning(
                    f"This worker run has already set {ml_class} on element {element.id}"
                )
            else:
                raise
            return

        # Propagate any other API error
        raise

    self.report.add_classification(element.id, ml_class)

    return created

create_classifications

create_classifications(element, classifications)

Create multiple classifications at once on the given element through the API.

Parameters:

Name	Type	Description	Default
element	Union[Element, CachedElement]	The element to create classifications on.	required
classifications	List[Dict[str, Union[str, float, bool]]]	The classifications to create, a list of dicts. Each of them contains a ml_class_id (str), the ID of the MLClass for this classification; a confidence (float), the confidence score, between 0 and 1; a high_confidence (bool), the high confidence state of the classification.	required

Returns:

Type	Description
List[Dict[str, Union[str, float, bool]]]	List of created classifications, as returned in the classifications field by the CreateClassifications API endpoint.

Source code in arkindex_worker/worker/classification.py

def create_classifications(
    self,
    element: Union[Element, CachedElement],
    classifications: List[Dict[str, Union[str, float, bool]]],
) -> List[Dict[str, Union[str, float, bool]]]:
    """
    Create multiple classifications at once on the given element through the API.

    :param element: The element to create classifications on.
    :param classifications: The classifications to create, a list of dicts. Each of them contains
        a **ml_class_id** (str), the ID of the MLClass for this classification;
        a **confidence** (float), the confidence score, between 0 and 1;
        a **high_confidence** (bool), the high confidence state of the classification.

    :returns: List of created classifications, as returned in the ``classifications`` field by
       the ``CreateClassifications`` API endpoint.
    """
    assert element and isinstance(
        element, (Element, CachedElement)
    ), "element shouldn't be null and should be an Element or CachedElement"
    assert classifications and isinstance(
        classifications, list
    ), "classifications shouldn't be null and should be of type list"

    for index, classification in enumerate(classifications):
        ml_class_id = classification.get("ml_class_id")
        assert ml_class_id and isinstance(
            ml_class_id, str
        ), f"Classification at index {index} in classifications: ml_class_id shouldn't be null and should be of type str"

        # Make sure it's a valid UUID
        try:
            UUID(ml_class_id)
        except ValueError:
            raise ValueError(
                f"Classification at index {index} in classifications: ml_class_id is not a valid uuid."
            )

        confidence = classification.get("confidence")
        assert (
            confidence is not None
            and isinstance(confidence, float)
            and 0 <= confidence <= 1
        ), f"Classification at index {index} in classifications: confidence shouldn't be null and should be a float in [0..1] range"

        high_confidence = classification.get("high_confidence")
        if high_confidence is not None:
            assert isinstance(
                high_confidence, bool
            ), f"Classification at index {index} in classifications: high_confidence should be of type bool"

    if self.is_read_only:
        logger.warning(
            "Cannot create classifications as this worker is in read-only mode"
        )
        return

    created_cls = self.request(
        "CreateClassifications",
        body={
            "parent": str(element.id),
            "worker_run_id": self.worker_run_id,
            "classifications": classifications,
        },
    )["classifications"]

    for created_cl in created_cls:
        created_cl["class_name"] = self.retrieve_ml_class(created_cl["ml_class"])
        self.report.add_classification(element.id, created_cl["class_name"])

    if self.use_cache:
        # Store classifications in local cache
        try:
            to_insert = [
                {
                    "id": created_cl["id"],
                    "element_id": element.id,
                    "class_name": created_cl.pop("class_name"),
                    "confidence": created_cl["confidence"],
                    "state": created_cl["state"],
                    "worker_run_id": self.worker_run_id,
                }
                for created_cl in created_cls
            ]
            CachedClassification.insert_many(to_insert).execute()
        except IntegrityError as e:
            logger.warning(
                f"Couldn't save created classifications in local cache: {e}"
            )

    return created_cls