Merge pull request #18 from R-ArcGIS/arcreq

Generic base request function

DESCRIPTION

@@ -21,7 +21,7 @@ URL: https://github.com/R-ArcGIS/arcgisutils,
 BugReports: https://github.com/R-ArcGIS/arcgisutils/issues
 Imports: 
     dbplyr,
-    httr2 >= 1.0.0,
+    httr2 (>= 1.0.0),
     jsonify,
     Rcpp,
     RcppSimdJson,

NAMESPACE

@@ -20,6 +20,7 @@ S3method(has_z,sfc)
 S3method(has_z,sfg)
 export("%||%")
 export(arc_agent)
+export(arc_base_req)
 export(arc_host)
 export(arc_token)
 export(as_esri_features)

NEWS.md

@@ -1,5 +1,6 @@
 # arcgisutils (development version)
 
+- `arc_base_req()` is introduce creating a standardized way to making base httr2 request objects. 
 - httr2 must be >= 1.0.0 now
 * New function `arc_agent()` is added to set a package sepcific user agent 
 * `fetch_layer_metadata()` now puts `f=json` in the url instead of the request body

R/arc-base-req.R

@@ -0,0 +1,43 @@
+#' Generate base request
+#'
+#' This function takes a url and creates a basic httr2 request that
+#' adds the user-agent and adds an authorization token to the
+#' `X-Esri-Authorization` header.
+#'
+#' @param url a valid url that is passed to [`httr2::request()`]
+#' @param token an object of class `httr2_token` as generated by [`auth_code()`]
+#'  or related function
+#' @param error_call the caller environment to be used when propagating errors.
+#' @export
+#' @examples
+#' arc_base_req("https://arcgis.com")
+arc_base_req <- function(url, token = NULL, error_call = rlang::caller_env()) {
+  # set the user agent
+  req <- arc_agent(httr2::request(url))
+
+  # if token is not missing, check it
+  if (!is.null(token)) {
+
+    # ensure that the token is an httr2_token
+    obj_check_token(token, error_call)
+
+    # set the auth header
+    req <- httr2::req_headers(
+      req,
+      "X-Esri-Authorization" = paste("Bearer", token[["access_token"]])
+    )
+  }
+
+  req
+}
+
+
+
+obj_check_token <- function(token, call = rlang::caller_env()) {
+  if (!rlang::inherits_only(token, "httr2_token")) {
+    cli::cli_abort(
+      "{.arg token} must be an {.cls httr2_token} not {.cls {class(token)}}"
+    )
+  }
+  invisible(token)
+}