arcgisutils 0.3.0

All geometry conversion functions: as_esri_geometry(), as_esri_features(), as_esri_featureset(), as_features() and as_featureset() have been rewritten from the ground up using Rust and extendr.
- arcgisutils now requires Rust to build from source
- jsonify is moved to Suggests
- as_geometry() is no longer exported
- ... argument is removed
auth_key() is added to support authorization with an API key for ArcGIS Developers accounts
catch_error() is a new function which parses a string and catches the error as an object. This is useful when processing multiple responses at once.
rbind_results() is a new helper function that combines a list of results as efficiently as possible.
arc_base_req() gains two new arguments path and query which allows you to add query parameters and paths to the generated base request
arc_self_meta() is a new function to provide access to the /self endpoint. Closes #32
Null geometries are parsed into empty Geometry Collections using sf::st_geometrycollection() Fixed #168
When Esri JSON contains 0 features, parse_esri_json() will create an empty data.frame with the fields that are returned with the appropriate R type.

arcgisutils 0.2.0

parse_esri_json() will return an empty data.frame in the presence of empty results an error. If an error is present, the error is reported
Breaking change to how authorization tokens are handled
- Tokens are now stored in internal environment token_env
- set_auth_token() removed in favor of set_arc_token()
- set_arc_token() allows for multiple named keys which are set to the token_env
- arc_token() fetches tokens directly from the token_env
- unset_arc_token() removes tokens from token_env
- intended to be used with arc_base_req()
arc_base_req() is introduce creating a standardized way to making base httr2 request objects.
- #19
httr2 must be >= 1.0.0 now

New function arc_agent() is added to set a package specific user agent
fetch_layer_metadata() now puts f=json in the url instead of the request body
- accepts NULL tokens
- uses req_auth_bearer_token() to include token in header
- #8
Define arc_token() to get "ARCGIS_TOKEN" environment variable. This ensures that empty strings do not cause HTTP 498 "invalid token" error by returning NULL in stead of an empty string. (#6) @kbvernon