api keys: add API key usage tracking.

Track when an API key was last used, which IP address last used it, and
how many times it's been used overall.

This is so you can tell when an API key was last used, so you know if
the key is safe to delete, and so you can tell if an unrecognized IP has
used your key.

CHANGELOG.md

@@ -3,6 +3,8 @@
 ### API Changes
 
 * You can now have multiple API keys.
+* You can now see when your API keys were last used, how many times they've
+  been used, and which IP address last used them.
 * API keys can be restricted to only work with certain IPs or certain API
   endpoints.
 * If you're an app or script developer, and you have an app that requests API

app/logical/session_loader.rb

@@ -90,6 +90,7 @@ class SessionLoader
   def authenticate_api_key(name, key)
     user, api_key = User.find_by_name(name)&.authenticate_api_key(key)
     raise AuthenticationFailure if user.blank?
+    update_api_key(api_key)
     raise User::PrivilegeError if !api_key.has_permission?(request.remote_ip, request.params[:controller], request.params[:action])
     CurrentUser.user = user
   end
@@ -117,6 +118,11 @@ class SessionLoader
     CurrentUser.user.update_attribute(:last_ip_addr, @request.remote_ip)
   end
 
+  def update_api_key(api_key)
+    api_key.increment!(:uses, touch: :last_used_at)
+    api_key.update!(last_ip_address: request.remote_ip)
+  end
+
   def set_time_zone
     Time.zone = CurrentUser.user.time_zone
   end

app/views/api_keys/index.html.erb

@@ -51,14 +51,22 @@
           <%= safe_join(api_key.permitted_ip_addresses, "<br>".html_safe).presence || "All" %>
         <% end %>
 
-        <% if !params[:user_id].present? %>
-          <% t.column "User" do |api_key| %>
-            <%= link_to_user api_key.user %>
+        <% t.column :uses %>
+
+        <% t.column "Last Used" do |api_key| %>
+          <%= time_ago_in_words_tagged api_key.last_used_at %>
+
+          <% if api_key.last_ip_address.present? %>
+            <br>by <%= api_key.last_ip_address %>
           <% end %>
         <% end %>
 
         <% t.column "Created" do |api_key| %>
           <%= time_ago_in_words_tagged api_key.created_at %>
+
+          <% if !params[:user_id].present? %>
+            <br> by <%= link_to_user api_key.user %>
+          <% end %>
         <% end %>
 
         <% t.column column: "control" do |api_key| %>

test/functional/application_controller_test.rb

@@ -52,14 +52,20 @@ class ApplicationControllerTest < ActionDispatch::IntegrationTest
         should "succeed for api key matches" do
           basic_auth_string = "Basic #{::Base64.encode64("#{@user.name}:#{@api_key.key}")}"
           get edit_user_path(@user), headers: { HTTP_AUTHORIZATION: basic_auth_string }
+
           assert_response :success
+          assert_equal(1, @api_key.reload.uses)
+          assert_not_nil(@api_key.reload.last_used_at)
         end
 
         should "succeed when the user has multiple api keys" do
           @api_key2 = create(:api_key, user: @user)
           basic_auth_string = "Basic #{::Base64.encode64("#{@user.name}:#{@api_key2.key}")}"
           get edit_user_path(@user), headers: { HTTP_AUTHORIZATION: basic_auth_string }
+
           assert_response :success
+          assert_equal(1, @api_key2.reload.uses)
+          assert_not_nil(@api_key2.reload.last_used_at)
         end
 
         should "fail for api key mismatches" do
@@ -80,13 +86,19 @@ class ApplicationControllerTest < ActionDispatch::IntegrationTest
       context "using the api_key parameter" do
         should "succeed for api key matches" do
           get edit_user_path(@user), params: { login: @user.name, api_key: @api_key.key }
+
           assert_response :success
+          assert_equal(1, @api_key.reload.uses)
+          assert_not_nil(@api_key.reload.last_used_at)
         end
 
         should "succeed when the user has multiple api keys" do
           @api_key2 = create(:api_key, user: @user)
           get edit_user_path(@user), params: { login: @user.name, api_key: @api_key2.key }
+
           assert_response :success
+          assert_equal(1, @api_key2.reload.uses)
+          assert_not_nil(@api_key2.reload.last_used_at)
         end
 
         should "fail for api key mismatches" do
@@ -135,6 +147,10 @@ class ApplicationControllerTest < ActionDispatch::IntegrationTest
           ActionDispatch::Request.any_instance.stubs(:remote_ip).returns("2600:dead:beef::1")
           get posts_path, params: { login: @api_key.user.name, api_key: @api_key.key }
           assert_response 403
+
+          assert_equal(6, @api_key.reload.uses)
+          assert_equal("2600:dead:beef::1", @api_key.reload.last_ip_address.to_s)
+          assert_not_nil(@api_key.reload.last_used_at)
         end
 
         should "restrict requests to the permitted endpoints" do
@@ -152,6 +168,10 @@ class ApplicationControllerTest < ActionDispatch::IntegrationTest
 
           put post_path(@post), params: { login: @api_key.user.name, api_key: @api_key.key, post: { rating: "s" }}
           assert_response 403
+
+          assert_equal(4, @api_key.reload.uses)
+          assert_equal("127.0.0.1", @api_key.reload.last_ip_address.to_s)
+          assert_not_nil(@api_key.reload.last_used_at)
         end
       end