Glossary

A visual Layer to be displayed in a map. A frequent web map use case features a "base map" (a world map as we’re used to seeing it) displayed on the bottom of a map for context with additional data the user is working with layered on top. Any number of layers can be displayed on top of each other so it’s typical for all maps besides the basemap to include transparency where there is no data. An application may have different layers available depending on the business logic employed, tilegroxy has the ability to atomically serve up any number of independent layers. Layers are served by tilegroxy in the form of individual tiles in a gridded structure, which allows returning only the parts of the map that are currently visible and to cache data without being impacted by the specific positioning of the map. Each layer in tilegroxy primarily contains a Provider declaration that defines how data is retrieved.

The name of the layer as specified in incoming requests. The layer name is used, alongside tile coordinates, as the cache key. Layers are found based on the name in two ways 1) By matching the layer name against the layer’s pattern if one is specified or if not 2) by exactly matching the layer’s ID

A Provider is any source of geospatial data that defines what is seen in a layer. Tilegroxy includes a number of distinct Provider implementations, those often allow making web calls to an external service but in many cases can simply map to another Provider implementation with a mutation applied.

The Operator is the administrator who creates the tilegroxy configuration and utilizes it in their environment. This is in contrast to the User who consumes the tiles in some web application. Operator input (primarily configuration) is considered trusted and so has much lesser degree of scrutiny, for instance in a provider that utilizes a database it can be possible to inject arbitrary SQL with Operator input. Any input coming from a User in contrast is treated with a presumption of maliciousness.