Module gdalhelpers.checks.layer_checks

Functions

def check_is_layer(variable, variable_name)

Check if variable is ogr.Layer, raises TypeError otherwise.

Parameters

variable : ogr.Layer

Variable to check.

variable_name : str

Variable name for error message.

Returns

None

 

Raises

TypeError

If variable is not ogr.Layer.

Expand source code

def check_is_layer(variable: ogr.Layer, variable_name: str) -> None:
    """
    Check if `variable` is `ogr.Layer`, raises `TypeError` otherwise.

    Parameters
    ----------
    variable : ogr.Layer
        Variable to check.

    variable_name : str
        Variable name for error message.

    Returns
    -------
    None

    Raises
    ------
    TypeError
        If `variable` is not `ogr.Layer`.
    """

    if not isinstance(variable, ogr.Layer):
        raise TypeError("`{0}` must be of class `ogr.Layer`. `{0}` is of type `{1}`."
                        .format(variable_name, type(variable).__name__))

def check_is_layer_geometry_type(variable, variable_name, expected_geom_type)

Checks if variable (ogr.Layer) is of expected type or types, raises TypeError if not.

Parameters

variable : ogr.Layer

Variable to check.

variable_name : str

Variable name for error message.

expected_geom_type : int or list of int

Only values provided by ogr.wkbPoint etc. makes sense. Can be constructed as expected_geometry_type=ogr.wkbPoint or expected_geometry_type=[ogr.wkbPoint, ogr.wkbPoint25D, ogr.wkbPointZM ].

Returns

None

 

Raises

ValueError

If variable is not of expected_geometry_type.

Expand source code

def check_is_layer_geometry_type(variable: ogr.Layer,
                                 variable_name: str,
                                 expected_geom_type: Union[int, List[int]]) -> None:
    """
    Checks if `variable` (`ogr.Layer`) is of expected type or types, raises `TypeError` if not.

    Parameters
    ----------
    variable : ogr.Layer
        Variable to check.

    variable_name : str
        Variable name for error message.

    expected_geom_type : int or list of int
        Only values provided by ogr.wkbPoint etc. makes sense.
        Can be constructed as `expected_geometry_type=ogr.wkbPoint` or
        `expected_geometry_type=[ogr.wkbPoint, ogr.wkbPoint25D, ogr.wkbPointZM ]`.

    Returns
    -------
    None

    Raises
    ------
    ValueError
        If `variable` is not of `expected_geometry_type`.
    """

    check_is_layer(variable, variable_name)

    geometry_name = ogr.GeometryTypeToName(variable.GetGeomType())

    check: bool = False
    expected_geometry_name: str

    if isinstance(expected_geom_type, list):

        for egt in expected_geom_type:
            if variable.GetGeomType() == egt:
                check = True

        expected_geometry_name = [ogr.GeometryTypeToName(x) for x in expected_geom_type]
        expected_geometry_name = ", ".join(expected_geometry_name)
    else:
        expected_geometry_name = ogr.GeometryTypeToName(expected_geom_type)
        check = (variable.GetGeomType() == expected_geom_type)

    if not check:
        raise ValueError("`{0}` must be of geometry type/types `{1}`, but it is `{2}`.".
                         format(variable_name, expected_geometry_name, geometry_name))

def check_is_projected(layer, variable_name)

Check that layer is projected.

Parameters

layer : ogr.Layer

ogr.Layer

variable_name : str

Variable name for error message.

Returns

None

 

Raises

ValueError

If the Spatial Reference System of the layer is not specified or if it is not projected.

Expand source code

def check_is_projected(layer: ogr.Layer, variable_name: str,) -> None:
    """
    Check that layer is projected.

    Parameters
    ----------
    layer : ogr.Layer
        `ogr.Layer`

    variable_name : str
        Variable name for error message.

    Returns
    -------
    None

    Raises
    ------
    ValueError
        If the Spatial Reference System of the `layer` is not specified or if it is not projected.
    """

    if layer.GetSpatialRef() is None:
        raise ValueError("`{0}` layer does not have Spatial Reference specified.")
    else:
        srs_checks.check_srs_projected(layer.GetSpatialRef(), variable_name)

def check_layers_sr_are_same(layer1, layer1_name, layer2, layer2_name)

Check that Spatial Reference Systems of two layers are the same.

Parameters

layer1, layer2 : ogr.Layer

ogr.Layer to compare.

layer1_name, layer2_name : str

Names of the variables for error message.

Returns

None

 

Expand source code

def check_layers_sr_are_same(layer1: ogr.Layer, layer1_name: str,
                             layer2: ogr.Layer, layer2_name: str) -> None:
    """
    Check that Spatial Reference Systems of two layers are the same.

    Parameters
    ----------
    layer1, layer2 : ogr.Layer
        `ogr.Layer` to compare.

    layer1_name, layer2_name : str
        Names of the variables for error message.

    Returns
    -------
    None

    """
    srs_checks.check_srs_are_same(layer1.GetSpatialRef(), layer1_name,
                                  layer2.GetSpatialRef(), layer2_name)

def check_number_of_features(layer, variable_name, number)

Check if layer has specified (number) number of features.

Parameters

layer : ogr.Layer

ogr.Layer

variable_name : str

Variable name for error message.

number : int

Number of features the layer is expected to have.

Returns

None

 

Raises

AttributeError

If the number of features in layer does not equal to number.

Expand source code

def check_number_of_features(layer: ogr.Layer,
                             variable_name: str,
                             number: int):
    """
    Check if `layer` has specified (`number`) number of features.

    Parameters
    ----------
    layer : ogr.Layer
        `ogr.Layer`

    variable_name : str
        Variable name for error message.

    number : int
        Number of features the `layer` is expected to have.

    Returns
    -------
    None

    Raises
    ------
    AttributeError
        If the number of features in `layer` does not equal to `number`.
    """

    if not layer.GetFeatureCount() == number:
        raise AttributeError("Layer `{0}` must contain only `{1}` feature/s. Currently there are `{2}` features.".
                             format(variable_name, number, layer.GetFeatureCount()))

def does_field_exist(layer, field_name)

Verify if field with field_name exists in layer.

Parameters

layer : ogr.Layer

ogr.Layer to look for field.

field_name : str or None

Name of the field.

Returns

bool

True if field exists in the given ogr.Layer, False otherwise.

Expand source code

def does_field_exist(layer: ogr.Layer, field_name: Union[str, None]) -> bool:
    """
    Verify if field with `field_name` exists in layer.

    Parameters
    ----------
    layer : ogr.Layer
        `ogr.Layer` to look for field.

    field_name : str or None
        Name of the field.

    Returns
    -------
    bool
        `True` if field exists in the given `ogr.Layer`, `False` otherwise.
    """

    if field_name is None:
        return False

    field_index = layer.GetLayerDefn().GetFieldIndex(field_name)

    if field_index < 0:
        return False
    else:
        return True

def get_field_type(layer, field_name)

Get type of field in layer as string.

Parameters

layer : ogr.Layer

ogr.Layer to look for field type.

field_name : str

Name of the field to get the type.

Returns

str

Type of the field as string.

Expand source code

def get_field_type(layer: ogr.Layer, field_name: str) -> str:
    """
    Get type of field in `layer` as string.

    Parameters
    ----------
    layer : ogr.Layer
        `ogr.Layer` to look for field type.

    field_name : str
        Name of the field to get the type.

    Returns
    -------
    str
        Type of the field as `string`.

    """
    field_index = layer.GetLayerDefn().GetFieldIndex(field_name)

    return layer.GetLayerDefn().GetFieldDefn(field_index).GetType()

def is_field_of_type(layer, field_name, field_type)

Verify that field in layer is of given type.

Parameters

layer : ogr.Layer

ogr.Layer to look for field.

field_name : str

Name of the field.

field_type : int

Idetification of field type. It can be created as ogr.OFTReal, ogr.OFTString etc.

Returns

bool

True if the field is of given type, False otherwise.

Expand source code

def is_field_of_type(layer: ogr.Layer, field_name: str, field_type: int) -> bool:
    """
    Verify that field in layer is of given type.

    Parameters
    ----------
    layer : ogr.Layer
        `ogr.Layer` to look for field.

    field_name : str
        Name of the field.

    field_type : int
        Idetification of field type. It can be created as `ogr.OFTReal`, `ogr.OFTString` etc.

    Returns
    -------
    bool
        `True` if the field is of given type, `False` otherwise.
    """

    if field_type == get_field_type(layer, field_name):
        return True
    else:
        return False