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With Symfony2 the firewall comes with a built in feature: impersonate a user. We’ve been using impersonation as an admin tool for about 5 years as it is very effective for troubleshooting. When a user files a support ticket saying something isn’t showing properly to them or they are getting random errors it is very easy to just quickly switch to that user and see what they are seeing. As with all features, this one may not be appropriate for your application if your user expects no administrative staff to have access to his or her account.

While Symfony’s built in impersonation feature is a great step up from having to build it by hand, it still can be a bit more friendly. We’ve seen two additional functions we wanted the impersonation to handle. First, we wanted it to on exit from impersonating the user returns the user to where the user first started to impersonating. Currently it just brings you back to wherever you link the user. Second, if already impersonating a user and trying to start to impersonate another, we didn’t want it to throw an error but to quietly switch you. This functionality could lead to unwanted circumstances if an impersonating user believes they can impersonate another user, and then slowly just keep exiting impersonation of each user and go back up the chain they went down. However, in our situation the time admins hit this was when they’d impersonate one user, realize they clicked the wrong one, click back and try to impersonate a different user. As the browser uses it’s cached page when the user hits back they see the list of users as if they were an admin and can click on the correct user. If they do this they are hit with a 500 error, “You are already switched to X user”.

For both of our goals we overrode the built in switch user class. It is really easy to override, as all you need to do is specify in your parameters.yml “security.authentication.switchuser_listener.class: My\AppBundle\Listener\SwitchUser”. We used the built in class as our starting template: https://github.com/symfony/symfony/blob/2.5/src/Symfony/Component/Security/Http/Firewall/SwitchUserListener.php Our final class ended looking like:

Here are the specifics on what everything we did and why.

First feature: Redirecting the user on exiting impersonating a user to where they originally started impersonating them. As we didn’t want to go around our entire application updating logic for the exit impersonation links if we decided to later change the behavior, we decided to build the redirect into the class itself. We didn’t want to rely on the user’s browser referrer header, so instead we decided to on the links to impersonate a user to include a “returnTo” parameter. This parameter is set to the current URI (app.request.uri). At line 97 we save the returnTo parameter to the session, for later use. On line 93, as a user is switching (in this case exiting) a user, if the session has a stored “returnTo” URL, we assign it to the “$overrideURI” variable. On line 107 we have a bit of logic on if we redirect them to the default route or the “returnTo” URL. The reason for the additional “$this->useOverrideURI” variable on this line is for our second feature of switching between users when you are already impersonating one. As the logic all runs through the same routine, if you are simply switching to a new user from an already impersonated one, we don’t want to redirect you back to your original URL when you started all the impersonating, so we disregard the redirect in this case and redirect to the default route. An example of this is admin impersonates user A, then wants to impersonate user B. Upon impersonating user B, the admin does not want to be redirected back to the admin dashboard (the sessions returnTo URL), but to where the impersonate user link is pointing to (User B homepage).

Second feature: Allow users to impersonate a different user while already impersonating another. One Line 134 is where the original SwitchUserListener would usually throw a 500 error as you are already impersonating a user. Instead, we make sure that the original token has the appropriate permissions, if so it will not throw an exception. Line 159 is the other main update for this feature. If you are already impersonating a user and try to impersonate another user, upon exiting you want to go back to your original user. Now if a original impersonation token (user) exists, we keep that as the user you’ll be switched to when you exit the impersonation.

Posted In: General, PHP, Symfony, Tips n' Tricks

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Looking for a way to preview online display ads and automatically save a screenshot/grab/capture?

Based on conversations we’ve had with one of our consulting clients, Datapoint Media, who are very familiar with the online advertising industry, it became quickly apparent that there really isn’t a good automated solution currently out there. When a buyer asks for “proofs” of their banner ads on the main sites that they will appear in, Ad Operations personnel are faced with two less than thrilling (and quite time intensive) options:

  • Grab screenshots of the sites that the client would like to preview and download the standalone display ad images the client is buying. Then open up Photoshop or other photo editor and copy and paste those ad images over the existing banner ads on the screenshot of the target websites.
  • Wait until the campaign is in flight and hope to catch lightning in a bottle by loading up the website the ad is likely to rotate into, refreshing the page continuously until the ads the clients bought appear, and finally taking a screenshot of the site.

Imagine having to do this every day week in and week out for hundreds of client orders.

Given the strong demand for a tool and a lack of automated solutions, we worked with Datapoint Media to build a tool as part of their existing Audience Extension platform .

Here’s how the Banner Ad preview tool works:

  1. Simple web based UI allows users to enter a website URL for which they’d like to preview the ads on. Once selected, the website is displayed in an iframe “preview window” to allow the user to get the lay of the land and see the current ad layout of the website.
  2. Users can choose from 3 options on how they want to input the banner ad/creative images they want to display on the selected site. The 3 options are:
    • Upload the actual image file(s)
    • Enter the url(s) of the creative images
    • Enter the Ad Server (such as Google’s DoubleClick For Publishers DFP) line item/ campaign ID that contains the creative ad imageimg1
  3. At this point, users submit the preview request. If they chose the Ad Server ID entry method, the Ad Servers API is pinged for a listing of all the associated creative images. After that, users select which creatives they want to include in the screenshot.img2
  4. The request is placed in a queue to be automatically processed. Next, users are presented with a confirmation that they will receive an email with the screenshot file attached within a few minutes. No need for any more work to be done by humans, it’s time for the robots to do the heavy lifting.
  5. Behind the scenes the tool loads up an “invisible” browser window on the server which points to the target website using a technology called PhantomJS. Next it executes a series of javascript commands to inspect the website determining where the valid ad slots are located. Once the slots are defined, it matches up the open slots with the dimensions of the banner ads that the user has selected. If the dimensions match, it replaces the existing ads on the website with the user entered banner ads and takes a screenshot.image03
  6. The resulting screenshot file is saved on the application server and automatically emailed to the user.

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If you have any questions or are interested in gaining access to the tool, feel free to contact the guys over at http://www.datapointmedia.com.

 

 

Posted In: General

In case you missed some, we’ve got a run down of some of the crazy stuff from last week! The Europeans landed on a comet, Microsoft is open sourcing .NET, and there’s a new variety of Firefox just for developers. Oh and we found an awesome list of UI kits!

Posted In: Friday Links

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Net Neutrality has been all over the news lately and I’ve been fielding a couple of questions related to it. At Setfive, we think it’s a critically important issue, both to startups and the technology infrastructure of the United States as a whole. Because of that, we decided to pull together an overview, some history, and key outcomes surrounding the Net Neutrality debate. As always, questions or comments welcome!

What is Net Neutrality?
First coined by Columbia Law professor Tim Wu, network neutrality, or net neutrality for short, states that internet service providers (such as Verizon and Comcast) and governments should provide you with access to content and data regardless of where it came from equally. Internet service providers (ISPs) are not allowed to discriminate and slow speeds for one company in favor of its competitor.

Essentially, net neutrality maintains a free, open, and fair internet.

The Lead Up To January 14, 2014

  • In 2002, the FCC had the opportunity to regulate ISPs as it had done for the phone companies. Ultimately though, the FCC chose not to at all citing that ISPs are “information services”, completely different than the telecommunication services phone companies provide.
  • However a few years later, the FCC began to notice the enormous power and strength that ISPs had accumulated over the years. In an attempt to curb and regulate them, the FCC created the Open Internet Rules in 2010

The Open Internet Rules established:

  • Enforced transparency of ISPs operations and management of their networks
  • Prohibited ISPs from obstructing access to legal content and applications
  • Maintained an equal and fair playing field online by preventing ISPs from giving preference to one company over another. Essentially becoming the core of net neutrality

In response to these rules, Verizon brought the FCC to court in 2013 on the charge that the agency had no authority to use the Open Internet rules to regulate ISPs.

Fast forward to January 14, 2014

  • On this day, a DC circuit court determined in the Verizon Communications Inc. vs FCC case that portions of the Open Internet Rules especially the ones pertaining to an equal and fair internet could not be applied to ISPs.
  • The reasoning was that portions of the rules apply only to common carriers, which provide telecommunication services. But since ISPs are classified by the FCC as providers of information services, they’re not considered under the law as common carriers.

What does this ruling mean?
It eliminated the only existing rules protecting net neutrality. As a result, ISPs can now:

  • Charge companies fees for “premium” access to their consumers. Think Verizon charging Netflix to stream to their customers at better rates.
  • Selectively prioritize one source of traffic over another. Think Comcast prioritizing delivering its Xfinity onDemand service over HBO Go.
  • And of course, create “slow lanes” and “fast lanes” paving the way to charging for ala carte Internet packages, just like TV. Imagine seeing errors like: “Sorry! You need to subscribe to the ‘social package’ to access this site.”

What’s the president’s stance on all this?
He’s pro net neutrality and has urged the FCC to establish strong rules that would protect it. However since the FCC is an independent government agency, Obama has no direct influence. Additionally, in a bitterly divided congress some hardline Republicans are taking an anti-Net Neutrality stance to pander to their base. See The Oatmeal on Ted Cruz.

What’s next?
The FCC does have the power to reclassify ISPs as telecommunication service providers and thus subject them to the Open Internet Rules. What it decided to do instead is to create a new net neutrality framework that would hold up in court while at the same time satisfy both sides.

Right now, everyone is in a holding pattern waiting for the FCC to make a final announcement.

Posted In: General

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Welcome to the weekend! We’ve rounded up some interesting reading to carry you through the till Monday. Fire up your iPad, grab some cider, and snuggle up with a blanket:

Posted In: Friday Links

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