diff --git a/app/controllers/api/push_controller.rb b/app/controllers/api/push_controller.rb
index bc547d6530..75a1f757b4 100644
--- a/app/controllers/api/push_controller.rb
+++ b/app/controllers/api/push_controller.rb
@@ -2,36 +2,66 @@
 
 class Api::PushController < ApiController
   def update
-    mode          = params['hub.mode']
-    topic         = params['hub.topic']
-    callback      = params['hub.callback']
-    lease_seconds = params['hub.lease_seconds']
-    secret        = params['hub.secret']
+    response, status = process_push_request
+    render plain: response, status: status
+  end
+
+  private
 
-    case mode
+  def process_push_request
+    case hub_mode
     when 'subscribe'
-      response, status = Pubsubhubbub::SubscribeService.new.call(topic_to_account(topic), callback, secret, lease_seconds)
+      Pubsubhubbub::SubscribeService.new.call(account_from_topic, hub_callback, hub_secret, hub_lease_seconds)
     when 'unsubscribe'
-      response, status = Pubsubhubbub::UnsubscribeService.new.call(topic_to_account(topic), callback)
+      Pubsubhubbub::UnsubscribeService.new.call(account_from_topic, hub_callback)
     else
-      response = "Unknown mode: #{mode}"
-      status   = 422
+      ["Unknown mode: #{hub_mode}", 422]
     end
+  end
 
-    render plain: response, status: status
+  def hub_mode
+    params['hub.mode']
   end
 
-  private
+  def hub_topic
+    params['hub.topic']
+  end
+
+  def hub_callback
+    params['hub.callback']
+  end
+
+  def hub_lease_seconds
+    params['hub.lease_seconds']
+  end
+
+  def hub_secret
+    params['hub.secret']
+  end
 
-  def topic_to_account(topic_url)
-    return if topic_url.blank?
+  def account_from_topic
+    if hub_topic.present? && local_domain? && account_feed_path?
+      Account.find_local(hub_topic_params[:username])
+    end
+  end
 
-    uri    = Addressable::URI.parse(topic_url).normalize
-    params = Rails.application.routes.recognize_path(uri.path)
-    domain = uri.host + (uri.port ? ":#{uri.port}" : '')
+  def hub_topic_params
+    @_hub_topic_params ||= Rails.application.routes.recognize_path(hub_topic_uri.path)
+  end
 
-    return unless TagManager.instance.web_domain?(domain) && params[:controller] == 'accounts' && params[:action] == 'show' && params[:format] == 'atom'
+  def hub_topic_uri
+    @_hub_topic_uri ||= Addressable::URI.parse(hub_topic).normalize
+  end
+
+  def local_domain?
+    TagManager.instance.web_domain?(hub_topic_domain)
+  end
+
+  def hub_topic_domain
+    hub_topic_uri.host + (hub_topic_uri.port ? ":#{hub_topic_uri.port}" : '')
+  end
 
-    Account.find_local(params[:username])
+  def account_feed_path?
+    hub_topic_params[:controller] == 'accounts' && hub_topic_params[:action] == 'show' && hub_topic_params[:format] == 'atom'
   end
 end
diff --git a/spec/controllers/api/push_controller_spec.rb b/spec/controllers/api/push_controller_spec.rb
index e699006f7b..18bfa70e57 100644
--- a/spec/controllers/api/push_controller_spec.rb
+++ b/spec/controllers/api/push_controller_spec.rb
@@ -3,11 +3,56 @@ require 'rails_helper'
 RSpec.describe Api::PushController, type: :controller do
   describe 'POST #update' do
     context 'with hub.mode=subscribe' do
-      pending
+      it 'creates a subscription' do
+        service = double(call: ['', 202])
+        allow(Pubsubhubbub::SubscribeService).to receive(:new).and_return(service)
+        account = Fabricate(:account)
+        account_topic_url = "https://#{Rails.configuration.x.local_domain}/users/#{account.username}.atom"
+        post :update, params: {
+          'hub.mode' => 'subscribe',
+          'hub.topic' => account_topic_url,
+          'hub.callback' => 'https://callback.host/api',
+          'hub.lease_seconds' => '3600',
+          'hub.secret' => 'as1234df',
+        }
+
+        expect(service).to have_received(:call).with(
+          account,
+          'https://callback.host/api',
+          'as1234df',
+          '3600',
+        )
+        expect(response).to have_http_status(:success)
+      end
     end
 
     context 'with hub.mode=unsubscribe' do
-      pending
+      it 'unsubscribes the account' do
+        service = double(call: ['', 202])
+        allow(Pubsubhubbub::UnsubscribeService).to receive(:new).and_return(service)
+        account = Fabricate(:account)
+        account_topic_url = "https://#{Rails.configuration.x.local_domain}/users/#{account.username}.atom"
+        post :update, params: {
+          'hub.mode' => 'unsubscribe',
+          'hub.topic' => account_topic_url,
+          'hub.callback' => 'https://callback.host/api',
+        }
+
+        expect(service).to have_received(:call).with(
+          account,
+          'https://callback.host/api',
+        )
+        expect(response).to have_http_status(:success)
+      end
+    end
+
+    context 'with unknown mode' do
+      it 'returns an unknown mode error' do
+        post :update, params: { 'hub.mode' => 'fake' }
+
+        expect(response).to have_http_status(422)
+        expect(response.body).to match(/Unknown mode/)
+      end
     end
   end
 end