API: Memoize the current_user so that the sudo can work properly

The issue was arising when `#current_user` was called a second time
after a user was impersonated: the `User#is_admin?` check would be
performed on it and it would fail.

Signed-off-by: Rémy Coutable <remy@rymai.me>

2 files changed, 66 insertions, 42 deletions

diff --git a/spec/requests/api/api_helpers_spec.rb b/spec/requests/api/helpers_spec.rb
index 3f34309f419..573154f69b4 100644
--- a/spec/requests/api/api_helpers_spec.rb
+++ b/spec/requests/api/helpers_spec.rb
@@ -2,7 +2,6 @@ require 'spec_helper'
 
 describe API::Helpers, api: true do
   include API::Helpers
-  include ApiHelpers
   include SentryHelper
 
   let(:user) { create(:user) }
@@ -13,17 +12,17 @@ describe API::Helpers, api: true do
   let(:env) { { 'REQUEST_METHOD' => 'GET' } }
   let(:request) { Rack::Request.new(env) }
 
-  def set_env(token_usr, identifier)
+  def set_env(user_or_token, identifier)
     clear_env
     clear_param
-    env[API::Helpers::PRIVATE_TOKEN_HEADER] = token_usr.private_token
+    env[API::Helpers::PRIVATE_TOKEN_HEADER] = user_or_token.respond_to?(:private_token) ? user_or_token.private_token : user_or_token
     env[API::Helpers::SUDO_HEADER] = identifier
   end
 
-  def set_param(token_usr, identifier)
+  def set_param(user_or_token, identifier)
     clear_env
     clear_param
-    params[API::Helpers::PRIVATE_TOKEN_PARAM] = token_usr.private_token
+    params[API::Helpers::PRIVATE_TOKEN_PARAM] = user_or_token.respond_to?(:private_token) ? user_or_token.private_token : user_or_token
     params[API::Helpers::SUDO_PARAM] = identifier
   end
 
@@ -163,6 +162,13 @@ describe API::Helpers, api: true do
               expect(current_user).to eq(user)
             end
 
+            it 'memoize the current_user: sudo permissions are not run against the sudoed user' do
+              set_env(admin, user.id)
+
+              expect(current_user).to eq(user)
+              expect(current_user).to eq(user)
+            end
+
             it 'handles sudo to oneself' do
               set_env(admin, admin.id)
 
@@ -294,33 +300,48 @@ describe API::Helpers, api: true do
     end
   end
 
-  describe '.sudo_identifier' do
-    it "returns integers when input is an int" do
-      set_env(admin, '123')
-      expect(sudo_identifier).to eq(123)
-      set_env(admin, '0001234567890')
-      expect(sudo_identifier).to eq(1234567890)
-
-      set_param(admin, '123')
-      expect(sudo_identifier).to eq(123)
-      set_param(admin, '0001234567890')
-      expect(sudo_identifier).to eq(1234567890)
+  describe '.sudo?' do
+    context 'when no sudo env or param is passed' do
+      before do
+        doorkeeper_guard_returns(nil)
+      end
+
+      it 'returns false' do
+        expect(sudo?).to be_falsy
+      end
     end
 
-    it "returns string when input is an is not an int" do
-      set_env(admin, '12.30')
-      expect(sudo_identifier).to eq("12.30")
-      set_env(admin, 'hello')
-      expect(sudo_identifier).to eq('hello')
-      set_env(admin, ' 123')
-      expect(sudo_identifier).to eq(' 123')
-
-      set_param(admin, '12.30')
-      expect(sudo_identifier).to eq("12.30")
-      set_param(admin, 'hello')
-      expect(sudo_identifier).to eq('hello')
-      set_param(admin, ' 123')
-      expect(sudo_identifier).to eq(' 123')
+    context 'when sudo env or param is passed', 'user is not an admin' do
+      before do
+        set_env(user, '123')
+      end
+
+      it 'returns an 403 Forbidden' do
+        expect { sudo? }.to raise_error '403 - {"message"=>"403 Forbidden  - Must be admin to use sudo"}'
+      end
+    end
+
+    context 'when sudo env or param is passed', 'user is admin' do
+      context 'personal access token is used' do
+        before do
+          personal_access_token = create(:personal_access_token, user: admin)
+          set_env(personal_access_token.token, user.id)
+        end
+
+        it 'returns an 403 Forbidden' do
+          expect { sudo? }.to raise_error '403 - {"message"=>"403 Forbidden  - Private token must be specified in order to use sudo"}'
+        end
+      end
+
+      context 'private access token is used' do
+        before do
+          set_env(admin.private_token, user.id)
+        end
+
+        it 'returns true' do
+          expect(sudo?).to be_truthy
+        end
+      end
     end
   end
 
diff --git a/spec/requests/api/users_spec.rb b/spec/requests/api/users_spec.rb
index c37dbfa0a33..9e317f3a7e9 100644
--- a/spec/requests/api/users_spec.rb
+++ b/spec/requests/api/users_spec.rb
@@ -651,13 +651,12 @@ describe API::Users, api: true  do
   end
 
   describe "GET /user" do
-    let(:personal_access_token) { create(:personal_access_token, user: user) }
-    let(:private_token) { user.private_token }
+    let(:personal_access_token) { create(:personal_access_token, user: user).token }
 
     context 'with regular user' do
       context 'with personal access token' do
         it 'returns 403 without private token when sudo is defined' do
-          get api("/user?private_token=#{personal_access_token.token}&sudo=#{user.id}")
+          get api("/user?private_token=#{personal_access_token}&sudo=123")
 
           expect(response).to have_http_status(403)
         end
@@ -665,7 +664,7 @@ describe API::Users, api: true  do
 
       context 'with private token' do
         it 'returns 403 without private token when sudo defined' do
-          get api("/user?private_token=#{private_token}&sudo=#{user.id}")
+          get api("/user?private_token=#{user.private_token}&sudo=123")
 
           expect(response).to have_http_status(403)
         end
@@ -676,40 +675,44 @@ describe API::Users, api: true  do
 
         expect(response).to have_http_status(200)
         expect(response).to match_response_schema('user/public')
+        expect(json_response['id']).to eq(user.id)
       end
     end
 
     context 'with admin' do
-      let(:user) { create(:admin) }
+      let(:admin_personal_access_token) { create(:personal_access_token, user: admin).token }
 
       context 'with personal access token' do
         it 'returns 403 without private token when sudo defined' do
-          get api("/user?private_token=#{personal_access_token.token}&sudo=#{user.id}")
+          get api("/user?private_token=#{admin_personal_access_token}&sudo=#{user.id}")
 
           expect(response).to have_http_status(403)
         end
 
-        it 'returns current user without private token when sudo not defined' do
-          get api("/user?private_token=#{personal_access_token.token}")
+        it 'returns initial current user without private token when sudo not defined' do
+          get api("/user?private_token=#{admin_personal_access_token}")
 
           expect(response).to have_http_status(200)
           expect(response).to match_response_schema('user/public')
+          expect(json_response['id']).to eq(admin.id)
         end
       end
 
       context 'with private token' do
-        it 'returns current user with private token when sudo defined' do
-          get api("/user?private_token=#{private_token}&sudo=#{user.id}")
+        it 'returns sudoed user with private token when sudo defined' do
+          get api("/user?private_token=#{admin.private_token}&sudo=#{user.id}")
 
           expect(response).to have_http_status(200)
           expect(response).to match_response_schema('user/login')
+          expect(json_response['id']).to eq(user.id)
         end
 
-        it 'returns current user without private token when sudo not defined' do
-          get api("/user?private_token=#{private_token}")
+        it 'returns initial current user without private token when sudo not defined' do
+          get api("/user?private_token=#{admin.private_token}")
 
           expect(response).to have_http_status(200)
           expect(response).to match_response_schema('user/public')
+          expect(json_response['id']).to eq(admin.id)
         end
       end
     end