The `get_map` map function ignores the “source” parameter in ggmap package

Question

When using the function get_map() I receive an error prompting to supply an google-API-key though I use the parameter "source":

location = colMeans(city[,c('coords_x1', 'coords_x2')])#mitte
names(location) <- c('lat', 'lon')

get_map(location = location, source='osm')
note : locations should be specified in the lon/lat format, not lat/lon.
Error: Google now requires an API key.
       See ?register_google for details.

It seems as if the parameter is ignored.

Answer 1

The solution lies in the way "location" is used in the query. As long as no bbox is supplied ggmap will lookup in google for a correct bounding box. Henceforth the error occurs. Thus the following code works:

bbox <- make_bbox(stadt$coords_x1, stadt$coords_x2, f = .05)


map <- get_map(location = bbox, source='osm') 
ggmap(map) + geom_point(data=stadt, aes(x=coords_x1, y=coords_x2, color=akaQuote))

Using OSM as a source a bounding box has to be passed to the get_map function.