Open Street Map

This workflow uses the OpenStreetMap nodes from the Geospatial Extension, concretely the Boundary Map and POIs (Point of Interest) to build a map of the Tacoma International Airport (WA, USA) showing the airport area and highlighting the restaurants.

To use the workflow, download and run it on the KNIME Analytics Platform. For optimal performance using the Geospatial Analytics extension, make sure you are using version 4.7.4 or higher.

To start, enter the name of the Tacoma International Airport into the OSM Boundary Map node. This process is known as Geocoding, producing a polygon displaying the airport's area as output.

As the node description advise: "The queries you provide must be resolvable to places in the Nominatim database". For more information about the type of queries allowed, please refer to the link in the External Resources section.

The Nominatim documentation guides creating search queries: "Free-form query string to search for. Free-form queries are processed first left-to-right and then right-to-left if that fails. So, you may search for pilkington avenue, birmingham as well as for birmingham, pilkington avenue. Commas are optional but improve performance by reducing the complexity of the search."

Once we have the airport polygon, our next step is to locate the restaurants within it. Our node for this task is OSM POIs (OpenStreetMap Points of Interest). Using a specific tag value, such as "restaurants," we search for amenities within the area of the polygon passed through the node's input port. To see a comprehensive list of available tags, please refer to the External Resource section.

We want to plot the airport area and the restaurants using a Geospatial View node. The name of each restaurant will appear as a tooltip when hovering over its location on the map. We plan to differentiate the colours of the restaurants and airport areas for a clear distinction.

To create the map mentioned above, we must first generate a column called "name" for the airport location. Then, we should add a "colour" column for each branch. Lastly, concatenating them through the intersection of columns, we can produce the desired table containing three features: "geometry," "colour," and "name."

External resources

• OSM POIs tag list
• OSM Boundary Map - Search Queries