geonode.thumbs.background

Attributes

logger
WMTS_TILEMATRIXSET_LEVELS

Classes

BaseThumbBackground	Helper class that provides a standard way to create an ABC using
GenericWMSBackground	Helper class that provides a standard way to create an ABC using
GenericXYZBackground	Helper class that provides a standard way to create an ABC using
WikiMediaTileBackground	Helper class that provides a standard way to create an ABC using
OSMTileBackground	Helper class that provides a standard way to create an ABC using
GenericWMTSBackground	Helper class that provides a standard way to create an ABC using

Module Contents

geonode.thumbs.background.logger

class geonode.thumbs.background.BaseThumbBackground(thumbnail_width: int, thumbnail_height: int, max_retries: int = 3, retry_delay: int = 1)

Bases: abc.ABC

Helper class that provides a standard way to create an ABC using inheritance.

thumbnail_width

thumbnail_height

max_retries

retry_delay

abstract fetch(bbox: List, *args, **kwargs) → PIL.Image.Image | None

Function fetching background image, based on the given BBOX. On error should raise an exception or return None.

Parameters:

bbox – a dataset compliant BBOX: [west, east, south, north, CRS]

class geonode.thumbs.background.GenericWMSBackground(thumbnail_width: int, thumbnail_height: int, max_retries: int = 3, retry_delay: int = 1)

Bases: BaseThumbBackground

Helper class that provides a standard way to create an ABC using inheritance.

options

service_url

dataset_name

format

version

styles

srid

bbox_to_projection(bbox: List)

Function converting BBOX to target projection system, keeping the order of the coordinates. To ensure no additional change is performed, conversion is based on top-left and bottom-right points conversion.

Parameters:

bbox – a dataset compliant BBOX: [west, east, south, north, CRS]

fetch(bbox: List, *args, **kwargs)

Function fetching background image, based on the given BBOX. On error should raise an exception or return None.

Parameters:

• bbox – a dataset compliant BBOX: [west, east, south, north, CRS]

• args – not used, kept for API compatibility

• kargs – not used, kept for API compatibility

class geonode.thumbs.background.GenericXYZBackground(thumbnail_width: int, thumbnail_height: int, max_retries: int = 3, retry_delay: int = 1)

Bases: BaseThumbBackground

Helper class that provides a standard way to create an ABC using inheritance.

options

url

tile_size

tms = False

crs = 'EPSG:3857'

_epsg3857_max_x = 20026376.39

_epsg3857_max_y = 20048966.1

_mercantile_bbox = None

point3857to4326(x, y)

point4326to3857(x, y)

bbox3857to4326(x_min, x_max, y_min, y_max)

Function converting BBOX from EPSG:3857 to EPSG:4326, keeping the order of the coordinates. To ensure no additional change is performed, conversion is based on top-left and bottom-right points conversion.

bbox4326to3857(x_min, x_max, y_min, y_max)

Function converting BBOX from EPSG:4326 to EPSG:3857, keeping the order of the coordinates. To ensure no additional change is performed, conversion is based on top-left and bottom-right points conversion.

fetch(bbox: List, zoom: int = None, *args, **kwargs)

The function fetching tiles from a Slippy Map provider, composing them into a single image, and cropping it to match the given BBOX. Retrieval of each tile is repeated self.max_retries times, waiting self.retry_delay seconds between consecutive requests.

Parameters:

• bbox – bounding box of the background image, dataset compliant format: [west, east, south, north, CRS]

• zoom – zoom with which to retrieve Slippy Map’s tiles (by default, it’s calculated based on width, height)

Returns:

None if the CRS is different from self.tiles_crs, or background Image

calculate_zoom()

class geonode.thumbs.background.WikiMediaTileBackground(thumbnail_width: int, thumbnail_height: int, max_retries: int = 3, retry_delay: int = 1)

Bases: GenericXYZBackground

Helper class that provides a standard way to create an ABC using inheritance.

url = 'https://maps.wikimedia.org/osm-intl/{z}/{x}/{y}.png'

tile_size = 256

class geonode.thumbs.background.OSMTileBackground(thumbnail_width: int, thumbnail_height: int, max_retries: int = 3, retry_delay: int = 1)

Bases: GenericXYZBackground

Helper class that provides a standard way to create an ABC using inheritance.

url = 'https://tile.openstreetmap.org/{z}/{x}/{y}.png'

tile_size = 256

geonode.thumbs.background.WMTS_TILEMATRIXSET_LEVELS = None

class geonode.thumbs.background.GenericWMTSBackground(thumbnail_width: int, thumbnail_height: int, max_retries: int = 3, retry_delay: int = 1)

Bases: BaseThumbBackground

Helper class that provides a standard way to create an ABC using inheritance.

options

levels

thumbnail_width

thumbnail_height

fetch(bbox: List, *args, **kwargs)

Function fetching background image, based on the given BBOX. On error should raise an exception or return None.

Parameters:

bbox – a dataset compliant BBOX: [west, east, south, north, CRS]

build_kvp_request(baseurl, layer, style, xyz)

build_request(xyz)

get_image_bbox_for_level(level, bbox)

get_tiles_coords(level, bbox)

get_level_for_targetpixelspan(target_pixelspan)

get_target_pixelspan(bbox)

get_levels_for_tilematrix()