X-Git-Url: https://git.openstreetmap.org/rails.git/blobdiff_plain/035254c5fbcf7c4a892532baefc79f5e9e4e7aa7..48d450060b3b5c19bb1fa8e85341d76177de26d2:/app/controllers/user_controller.rb

diff --git a/app/controllers/user_controller.rb b/app/controllers/user_controller.rb
index 36516f60f..923a6cfec 100644
--- a/app/controllers/user_controller.rb
+++ b/app/controllers/user_controller.rb
@@ -1,32 +1,98 @@
 class UserController < ApplicationController
-  layout 'site'
+  layout 'site', :except => :api_details
 
   before_filter :authorize, :only => [:api_details, :api_gpx_files]
-  before_filter :set_locale, :except => [:api_details, :api_gpx_files]
   before_filter :authorize_web, :except => [:api_details, :api_gpx_files]
-  before_filter :require_user, :only => [:set_home, :account, :go_public, :make_friend, :remove_friend, :upload_image, :delete_image]
+  before_filter :set_locale, :except => [:api_details, :api_gpx_files]
+  before_filter :require_user, :only => [:account, :go_public, :make_friend, :remove_friend]
   before_filter :check_database_readable, :except => [:api_details, :api_gpx_files]
-  before_filter :check_database_writable, :only => [:login, :new, :set_home, :account, :go_public, :make_friend, :remove_friend, :upload_image, :delete_image]
+  before_filter :check_database_writable, :only => [:login, :new, :account, :go_public, :make_friend, :remove_friend]
   before_filter :check_api_readable, :only => [:api_details, :api_gpx_files]
+  before_filter :require_allow_read_prefs, :only => [:api_details]
+  before_filter :require_allow_read_gpx, :only => [:api_gpx_files]
+  before_filter :require_cookies, :only => [:login, :confirm]
+  before_filter :require_administrator, :only => [:set_status, :delete, :list]
+  before_filter :lookup_this_user, :only => [:set_status, :delete]
 
   filter_parameter_logging :password, :pass_crypt, :pass_crypt_confirmation
 
+  cache_sweeper :user_sweeper, :only => [:account, :set_status, :delete]
+
   def save
-    @title = 'create account'
+    @title = t 'user.new.title'
 
     if Acl.find_by_address(request.remote_ip, :conditions => {:k => "no_account_creation"})
       render :action => 'new'
     else
-      @user = User.new(params[:user])
-
-      @user.visible = true
-      @user.data_public = true
-      @user.description = "" if @user.description.nil?
-      @user.creation_ip = request.remote_ip
+      #The redirect from the OpenID provider reenters here again 
+      #and we need to pass the parameters through to the  
+      #open_id_authentication function a second time 
+      if params[:open_id_complete] 
+        openid_verify('', true) 
+        #We have set the user.openid_url to nil beforehand. If it hasn't 
+        #been set to a new valid openid_url, it means the openid couldn't be validated 
+        if @user.nil? or @user.openid_url.nil? 
+          render :action => 'new' 
+          return 
+        end   
+      else
+        @user = User.new(params[:user])
+
+        @user.status = "pending"
+        @user.data_public = true
+        @user.description = "" if @user.description.nil?
+        @user.creation_ip = request.remote_ip
+        @user.languages = request.user_preferred_languages
+        #Set the openid_url to nil as for one it is used 
+        #to check if the openid could be validated and secondly 
+        #to not get dupplicate conflicts for an empty openid  
+        @user.openid_url = nil
+
+        if (!params[:user][:openid_url].nil? and params[:user][:openid_url].length > 0)
+          if (@user.pass_crypt.nil? or @user.pass_crypt.length == 0)
+            #if the password is empty, but we have a openid 
+            #then generate a random passowrd to disable 
+            #loging in via password 
+            @user.pass_crypt = ActiveSupport::SecureRandom.base64(16) 
+            @user.pass_crypt_confirmation = @user.pass_crypt 
+          end
+          #Validate all of the other fields before
+          #redirecting to the openid provider
+          if !@user.valid?
+            render :action => 'new'
+          else        
+            #TODO: Is it a problem to store the user variable with respect to password safty in the session variables?
+            #Store the user variable in the session for it to be accessible when redirecting back from the openid provider
+            session[:new_usr] = @user
+            begin
+              @norm_openid_url = OpenIdAuthentication.normalize_identifier(params[:user][:openid_url])
+            rescue
+              flash.now[:error] = t 'user.login.openid invalid'
+              render :action => 'new'
+              return
+            end
+            #Verify that the openid provided is valid and that the user is the owner of the id
+            openid_verify(@norm_openid_url, true)
+            #openid_verify can return in two ways:
+            #Either it returns with a redirect to the openid provider who then freshly
+            #redirects back to this url if the openid is valid, or if the openid is not plausible
+            #and no provider for it could be found it just returns
+            #we want to just let the redirect through
+            if response.headers["Location"].nil?
+              render :action => 'new'
+            end
+          end
+          #At this point there was either an error and the page has been rendered,
+          #or there is a redirect to the openid provider and the rest of the method
+          #gets executed whenn this method gets reentered after redirecting back
+          #from the openid provider
+          return
+        end
+      end
 
       if @user.save
-        flash[:notice] = "User was successfully created. Check your email for a confirmation note, and you\'ll be mapping in no time :-)<br /><br />Please note that you won't be able to login until you've received and confirmed your email address.<br /><br />If you use an antispam system which sends confirmation requests then please make sure you whitelist webmaster@openstreetmap.org as we are unable to reply to any confirmation requests."
-        Notifier.deliver_signup_confirm(@user, @user.tokens.create)
+        flash[:notice] = t 'user.new.flash create success message'
+        Notifier.deliver_signup_confirm(@user, @user.tokens.create(:referer => params[:referer]))
         redirect_to :action => 'login'
       else
         render :action => 'new'
@@ -35,13 +101,21 @@ class UserController < ApplicationController
   end
 
   def account
-    @title = 'edit account'
-    if params[:user] and params[:user][:display_name] and params[:user][:description]
-      if params[:user][:email] != @user.email
-        @user.new_email = params[:user][:email]
-      end
+    @title = t 'user.account.title'
+    @tokens = @user.oauth_tokens.find :all, :conditions => 'oauth_tokens.invalidated_at is null and oauth_tokens.authorized_at is not null'
+
+    #The redirect from the OpenID provider reenters here again
+    #and we need to pass the parameters through to the 
+    #open_id_authentication function
+    if params[:open_id_complete]
+      openid_verify('', false)
+      @user.save
+      return
+    end
 
+    if params[:user] and params[:user][:display_name] and params[:user][:description]
       @user.display_name = params[:user][:display_name]
+      @user.new_email = params[:user][:new_email]
 
       if params[:user][:pass_crypt].length > 0 or params[:user][:pass_crypt_confirmation].length > 0
         @user.pass_crypt = params[:user][:pass_crypt]
@@ -49,127 +123,277 @@ class UserController < ApplicationController
       end
 
       @user.description = params[:user][:description]
+      @user.languages = params[:user][:languages].split(",")
+
+      case params[:image_action]
+        when "new" then @user.image = params[:user][:image]
+        when "delete" then @user.image = nil
+      end
+
       @user.home_lat = params[:user][:home_lat]
       @user.home_lon = params[:user][:home_lon]
 
+      @user.openid_url = nil if (params[:user][:openid_url].length == 0)
+
       if @user.save
-        if params[:user][:email] == @user.new_email
-          @notice = "User information updated successfully. Check your email for a note to confirm your new email address."
-          Notifier.deliver_email_confirm(@user, @user.tokens.create)
+        set_locale
+
+        if @user.new_email.nil? or @user.new_email.empty?
+          flash[:notice] = t 'user.account.flash update success'
         else
-          @notice = "User information updated successfully."
+          flash[:notice] = t 'user.account.flash update success confirm needed'
+
+          begin
+            Notifier.deliver_email_confirm(@user, @user.tokens.create)
+          rescue
+            # Ignore errors sending email
+          end
+        end
+
+        redirect_to :action => "account", :display_name => @user.display_name
+      end
+
+      if (params[:user][:openid_url].length > 0)
+        begin
+          @norm_openid_url = OpenIdAuthentication.normalize_identifier(params[:user][:openid_url])
+          if (@norm_openid_url != @user.openid_url)
+            #If the OpenID has changed, we want to check that it is a valid OpenID and one
+            #the user has control over before saving the openID as a password equivalent for
+            #the user.
+            openid_verify(@norm_openid_url, false)
+          end
+        rescue
+          flash.now[:error] = t 'user.login.openid invalid'
+        end
+      end
+
+    else
+      if flash[:errors]
+        flash[:errors].each do |attr,msg|
+          attr = "new_email" if attr == "email"
+          @user.errors.add(attr,msg)
         end
       end
     end
   end
 
-  def set_home
-    if params[:user][:home_lat] and params[:user][:home_lon]
-      @user.home_lat = params[:user][:home_lat].to_f
-      @user.home_lon = params[:user][:home_lon].to_f
-      if @user.save
-        flash[:notice] = "Home location saved successfully."
-        redirect_to :controller => 'user', :action => 'account'
+  def openid_specialcase_mapping(openid_url)
+    #Special case gmail.com, as it is pontentially a popular OpenID provider and unlike
+    #yahoo.com, where it works automatically, Google have hidden their OpenID endpoint
+    #somewhere obscure making it less userfriendly.
+    if (openid_url.match(/(.*)gmail.com(\/?)$/) or openid_url.match(/(.*)googlemail.com(\/?)$/) )
+      return 'https://www.google.com/accounts/o8/id'
+    end
+
+    return nil
+  end  
+
+  def openid_verify(openid_url,account_create)
+    authenticate_with_open_id(openid_url) do |result, identity_url|
+      if result.successful?
+        #We need to use the openid url passed back from the OpenID provider
+        #rather than the one supplied by the user, as these can be different.
+        #e.g. one can simply enter yahoo.com in the login box, i.e. no user specific url
+        #only once it comes back from the OpenID provider do we know the unique address for
+        #the user.
+        @user = session[:new_usr] unless @user #this is used for account creation when the user is not yet in the database
+        @user.openid_url = identity_url
+      elsif result.missing?
+        mapped_id = openid_specialcase_mapping(openid_url)
+        if mapped_id
+          openid_verify(mapped_id, account_create)
+        else
+          flash.now[:error] = t 'user.login.openid missing provider'
+        end
+      elsif result.invalid?
+        flash.now[:error] = t 'user.login.openid invalid'
+      else
+        flash.now[:error] = t 'user.login.auth failure'
+      end
+    end
+  end
+
+  def open_id_authentication(openid_url)
+    #TODO: only ask for nickname and email, if we don't already have a user for that openID, in which case
+    #email and nickname are already filled out. I don't know how to do that with ruby syntax though, as we
+    #don't want to duplicate the do block
+    #On the other hand it also doesn't matter too much if we ask every time, as the OpenID provider should
+    #remember these results, and shouldn't repromt the user for these data each time.
+    user = nil
+    authenticate_with_open_id(openid_url, :return_to => request.protocol + request.host_with_port + '/login?referer=' + params[:referer], :optional => [:nickname, :email]) do |result, identity_url, registration|
+      if result.successful?
+        #We need to use the openid url passed back from the OpenID provider
+        #rather than the one supplied by the user, as these can be different.
+        #e.g. one can simply enter yahoo.com in the login box, i.e. no user specific url
+        #only once it comes back from the OpenID provider do we know the unique address for
+        #the user.
+        user = User.find_by_openid_url(identity_url)
+        if user
+          if user.visible? and user.active?
+            session[:user] = user.id
+            session_expires_after 1.month if session[:remember]
+            return user
+          else
+            user = nil
+            flash.now[:error] = t 'user.login.account not active'
+          end
+        else
+          #We don't have a user registered to this OpenID. Redirect to the create account page
+          #with username and email filled in if they have been given by the OpenID provider through
+          #the simple registration protocol
+          redirect_to :controller => 'user', :action => 'new', :nickname => registration['nickname'], :email => registration['email'], :openid => identity_url
+        end
+      else if result.missing?
+             #Try and apply some heuristics to make common cases more userfriendly
+             mapped_id = openid_specialcase_mapping(openid_url)
+             if mapped_id
+               open_id_authentication(mapped_id)
+             else
+               flash.now[:error] = t 'user.login.openid missing provider'
+             end
+           else if result.invalid?
+                  flash.now[:error] = t 'user.login.openid invalid'
+                else
+                  flash.now[:error] = t 'user.login.auth failure'
+                end
+           end
       end
     end
+    return user
   end
 
   def go_public
     @user.data_public = true
     @user.save
-    flash[:notice] = 'All your edits are now public.'
+    flash[:notice] = t 'user.go_public.flash success'
     redirect_to :controller => 'user', :action => 'account', :display_name => @user.display_name
   end
 
   def lost_password
-    @title = 'lost password'
+    @title = t 'user.lost_password.title'
+
     if params[:user] and params[:user][:email]
-      user = User.find_by_email(params[:user][:email], :conditions => {:visible => true})
+      user = User.find_by_email(params[:user][:email], :conditions => {:status => ["pending", "active", "confirmed"]})
 
       if user
         token = user.tokens.create
         Notifier.deliver_lost_password(user, token)
-        @notice = "Sorry you lost it :-( but an email is on its way so you can reset it soon."
+        flash[:notice] = t 'user.lost_password.notice email on way'
+        redirect_to :action => 'login'
       else
-        @notice = "Couldn't find that email address, sorry."
+        flash.now[:error] = t 'user.lost_password.notice email cannot find'
       end
     end
   end
 
   def reset_password
-    @title = 'reset password'
-    if params['token']
+    @title = t 'user.reset_password.title'
+
+    if params[:token]
       token = UserToken.find_by_token(params[:token])
+
       if token
-        pass = OSM::make_token(8)
-        user = token.user
-        user.pass_crypt = pass
-        user.pass_crypt_confirmation = pass
-        user.active = true
-        user.email_valid = true
-        user.save!
-        token.destroy
-        Notifier.deliver_reset_password(user, pass)
-        flash[:notice] = "Your password has been changed and is on its way to your mailbox :-)"
+        @user = token.user
+
+        if params[:user]
+          @user.pass_crypt = params[:user][:pass_crypt]
+          @user.pass_crypt_confirmation = params[:user][:pass_crypt_confirmation]
+          @user.status = "active" if @user.status == "pending"
+          @user.email_valid = true
+
+          if @user.save
+            token.destroy
+            flash[:notice] = t 'user.reset_password.flash changed'
+            redirect_to :action => 'login'
+          end
+        end
       else
-        flash[:notice] = "Didn't find that token, check the URL maybe?"
+        flash[:error] = t 'user.reset_password.flash token bad'
+        redirect_to :action => 'lost_password'
       end
     end
-
-    redirect_to :action => 'login'
   end
 
   def new
-    @title = 'create account'
-    # The user is logged in already, so don't show them the signup page, instead
-    # send them to the home page
+    @title = t 'user.new.title'
+
+    # The user is logged in already, so don't show them the signup
+    # page, instead send them to the home page
     redirect_to :controller => 'site', :action => 'index' if session[:user]
+
+    @nickname = params['nickname']
+    @email = params['email']
+    @openID = params['openid']
+	
+    if !params['openid'].nil?
+	  flash.now[:notice] = t 'user.new.openID association'
+    end
   end
 
   def login
-    if session[:user]
-      # The user is logged in already, if the referer param exists, redirect them to that
-      if params[:referer]
-        redirect_to params[:referer]
+    @title = t 'user.login.title'
+
+    #The redirect from the OpenID provider reenters here again
+    #and we need to pass the parameters through to the 
+    # open_id_authentication function
+    if params[:open_id_complete]
+      user = open_id_authentication('')
+    elsif params[:user]
+      if !params[:user][:openid_url].nil? and !params[:user][:openid_url].empty?
+        session[:remember] = params[:remember_me]
+        #construct the openid request. This will redirect to the OpenID server to ask for validation
+        #The external OpenID server will then redirect back to the login method and reenters at the top
+        open_id_authentication(params[:user][:openid_url])
+        return
       else
-        redirect_to :controller => 'site', :action => 'index'
-      end
-      return
-    end
-    @title = 'login'
-    if params[:user]
-      email_or_display_name = params[:user][:email]
-      pass = params[:user][:password]
-      user = User.authenticate(:username => email_or_display_name, :password => pass)
-      if user
-        session[:user] = user.id
-        if params[:referer]
-          redirect_to params[:referer]
+        email_or_display_name = params[:user][:email]
+        pass = params[:user][:password]
+
+        if user = User.authenticate(:username => email_or_display_name, :password => pass)
+          session[:user] = user.id
+          session_expires_after 1.month if params[:remember_me]
+        elsif User.authenticate(:username => email_or_display_name, :password => pass, :pending => true)
+          flash.now[:error] = t 'user.login.account not active'
+        elsif User.authenticate(:username => email_or_display_name, :password => pass, :suspended => true)
+          flash.now[:error] = t 'user.login.account suspended'
         else
-          redirect_to :controller => 'site', :action => 'index'
+          flash.now[:error] = t 'user.login.auth failure'
         end
-        return
-      elsif User.authenticate(:username => email_or_display_name, :password => pass, :inactive => true)
-        @notice = "Sorry, your account is not active yet.<br>Please click on the link in the account confirmation email to activate your account."
+      end
+    end
+
+    if user
+      # The user is logged in, if the referer param exists, redirect
+      # them to that unless they've also got a block on them, in
+      # which case redirect them to the block so they can clear it.
+      if user.blocked_on_view
+        redirect_to user.blocked_on_view, :referrer => params[:referrer]
+      elsif params[:referer]
+        redirect_to params[:referer]
       else
-        @notice = "Sorry, couldn't log in with those details."
+        redirect_to :controller => 'site', :action => 'index'
       end
     end
   end
 
   def logout
-    if session[:token]
-      token = UserToken.find_by_token(session[:token])
-      if token
-        token.destroy
+    @title = t 'user.logout.title'
+
+    if params[:session] == request.session_options[:id]
+      if session[:token]
+        token = UserToken.find_by_token(session[:token])
+        if token
+          token.destroy
+        end
+        session[:token] = nil
+      end
+      session[:user] = nil
+      session_expires_automatically
+      if params[:referer]
+        redirect_to params[:referer]
+      else
+        redirect_to :controller => 'site', :action => 'index'
       end
-      session[:token] = nil
-    end
-    session[:user] = nil
-    if params[:referer]
-      redirect_to params[:referer]
-    else
-      redirect_to :controller => 'site', :action => 'index'
     end
   end
 
@@ -178,15 +402,20 @@ class UserController < ApplicationController
       token = UserToken.find_by_token(params[:confirm_string])
       if token and !token.user.active?
         @user = token.user
-        @user.active = true
+        @user.status = "active"
         @user.email_valid = true
         @user.save!
+        referer = token.referer
         token.destroy
-        flash[:notice] = 'Confirmed your account, thanks for signing up!'
+        flash[:notice] = t 'user.confirm.success'
         session[:user] = @user.id
-        redirect_to :action => 'account', :display_name => @user.display_name
+        unless referer.nil?
+          redirect_to referer
+        else
+          redirect_to :action => 'account', :display_name => @user.display_name
+        end
       else
-        @notice = 'Something went wrong confirming that user.'
+        flash.now[:error] = t 'user.confirm.failure'
       end
     end
   end
@@ -198,35 +427,21 @@ class UserController < ApplicationController
         @user = token.user
         @user.email = @user.new_email
         @user.new_email = nil
-        @user.active = true
         @user.email_valid = true
-        @user.save!
+        if @user.save
+          flash[:notice] = t 'user.confirm_email.success'
+        else
+          flash[:errors] = @user.errors
+        end
         token.destroy
-        flash[:notice] = 'Confirmed your email address, thanks for signing up!'
         session[:user] = @user.id
         redirect_to :action => 'account', :display_name => @user.display_name
       else
-        @notice = 'Something went wrong confirming that email address.'
+        flash.now[:error] = t 'user.confirm_email.failure'
       end
     end
   end
 
-  def upload_image
-    @user.image = params[:user][:image]
-    @user.save!
-    redirect_to :controller => 'user', :action => 'view', :display_name => @user.display_name
-  end
-
-  def delete_image
-    @user.image = nil
-    @user.save!
-    redirect_to :controller => 'user', :action => 'view', :display_name => @user.display_name
-  end
-
-  def api_details
-    render :text => @user.to_xml.to_s, :content_type => "text/xml"
-  end
-
   def api_gpx_files
     doc = OSM::API.new.get_xml_doc
     @user.traces.each do |trace|
@@ -236,50 +451,123 @@ class UserController < ApplicationController
   end
 
   def view
-    @this_user = User.find_by_display_name(params[:display_name], :conditions => {:visible => true})
+    @this_user = User.find_by_display_name(params[:display_name])
 
-    if @this_user
+    if @this_user and
+       (@this_user.visible? or (@user and @user.administrator?))
       @title = @this_user.display_name
     else
+      @title = t 'user.no_such_user.title'
       @not_found_user = params[:display_name]
       render :action => 'no_such_user', :status => :not_found
     end
   end
 
   def make_friend
-    if params[:display_name]     
+    if params[:display_name]
       name = params[:display_name]
-      new_friend = User.find_by_display_name(name, :conditions => {:visible => true})
+      new_friend = User.find_by_display_name(name, :conditions => {:status => ["active", "confirmed"]})
       friend = Friend.new
       friend.user_id = @user.id
       friend.friend_user_id = new_friend.id
       unless @user.is_friends_with?(new_friend)
         if friend.save
-          flash[:notice] = "#{name} is now your friend."
+          flash[:notice] = t 'user.make_friend.success', :name => name
           Notifier.deliver_friend_notification(friend)
         else
-          friend.add_error("Sorry, failed to add #{name} as a friend.")
+          friend.add_error(t('user.make_friend.failed', :name => name))
         end
       else
-        flash[:notice] = "You are already friends with #{name}."  
+        flash[:warning] = t 'user.make_friend.already_a_friend', :name => name
       end
 
-      redirect_to :controller => 'user', :action => 'view'
+      if params[:referer]
+        redirect_to params[:referer]
+      else
+        redirect_to :controller => 'user', :action => 'view'
+      end
     end
   end
 
   def remove_friend
-    if params[:display_name]     
+    if params[:display_name]
       name = params[:display_name]
-      friend = User.find_by_display_name(name, :conditions => {:visible => true})
+      friend = User.find_by_display_name(name, :conditions => {:status => ["active", "confirmed"]})
       if @user.is_friends_with?(friend)
         Friend.delete_all "user_id = #{@user.id} AND friend_user_id = #{friend.id}"
-        flash[:notice] = "#{friend.display_name} was removed from your friends."
+        flash[:notice] = t 'user.remove_friend.success', :name => friend.display_name
+      else
+        flash[:error] = t 'user.remove_friend.not_a_friend', :name => friend.display_name
+      end
+
+      if params[:referer]
+        redirect_to params[:referer]
       else
-        flash[:notice] = "#{friend.display_name} is not one of your friends."
+        redirect_to :controller => 'user', :action => 'view'
       end
+    end
+  end
+
+  ##
+  # sets a user's status
+  def set_status
+    @this_user.update_attributes(:status => params[:status])
+    redirect_to :controller => 'user', :action => 'view', :display_name => params[:display_name]
+  end
 
-      redirect_to :controller => 'user', :action => 'view'
+  ##
+  # delete a user, marking them as deleted and removing personal data
+  def delete
+    @this_user.delete
+    redirect_to :controller => 'user', :action => 'view', :display_name => params[:display_name]
+  end
+
+  ##
+  # display a list of users matching specified criteria
+  def list
+    if request.post?
+      ids = params[:user].keys.collect { |id| id.to_i }
+
+      User.update_all("status = 'confirmed'", :id => ids) if params[:confirm]
+      User.update_all("status = 'deleted'", :id => ids) if params[:hide]
+
+      redirect_to url_for(:status => params[:status], :ip => params[:ip], :page => params[:page])
+    else
+      conditions = Hash.new
+      conditions[:status] = params[:status] if params[:status]
+      conditions[:creation_ip] = params[:ip] if params[:ip]
+
+      @user_pages, @users = paginate(:users,
+                                     :conditions => conditions,
+                                     :order => :id,
+                                     :per_page => 50)
+    end
+  end
+
+private
+
+  ##
+  # require that the user is a administrator, or fill out a helpful error message
+  # and return them to the user page.
+  def require_administrator
+    if @user and not @user.administrator?
+      flash[:error] = t('user.filter.not_an_administrator')
+
+      if params[:display_name]
+        redirect_to :controller => 'user', :action => 'view', :display_name => params[:display_name]
+      else
+        redirect_to :controller => 'user', :action => 'login', :referer => request.request_uri
+      end
+    elsif not @user
+      redirect_to :controller => 'user', :action => 'login', :referer => request.request_uri
     end
   end
+
+  ##
+  # ensure that there is a "this_user" instance variable
+  def lookup_this_user
+    @this_user = User.find_by_display_name(params[:display_name])
+  rescue ActiveRecord::RecordNotFound
+    redirect_to :controller => 'user', :action => 'view', :display_name => params[:display_name] unless @this_user
+  end
 end