Add role search to organization memberships

Author: npendery

web/controllers/controller_helpers.ex

@@ -4,4 +4,9 @@ defmodule CodeCorps.ControllerHelpers do
     |> String.split(",")
     |> Enum.map(&String.to_integer(&1))
   end
+
+  def coalesce_string(string) do
+    string
+    |> String.split(",")
+  end
 end

web/controllers/organization_membership_controller.ex

@@ -19,6 +19,17 @@ defmodule CodeCorps.OrganizationMembershipController do
     render(conn, "index.json-api", data: memberships)
   end
 
+  def index(conn, %{"role" => roles}) do
+    roles = roles |> coalesce_string
+    memberships =
+      OrganizationMembership
+      |> preload([:organization, :member])
+      |> where([p], p.role in ^roles)
+      |> Repo.all
+
+    render(conn, "index.json-api", data: memberships)
+  end
+
   def index(conn, %{"organization_id" => organization_id}) do
     memberships =
       OrganizationMembership