Category: Symfony

Last week we were looking to leverage a set of JSON API endpoints in a Symfony2 project to power a single page Javascript app. The way the API had been setup, the routes were all secured with an HTTP Basic Auth firewall matching on “/api”. This worked great for the mobile apps but for a Javascript app it would be awkward to have the user re-enter their credentials to authorize the basic auth firewall. What we really wanted to do was to leave everything “as is” but have Symfony use the normal cookie based firewall when we passed in a special “isOnlineApp” parameters on the URL.

Unfortunately, setting something like this up with the default “pattern” setting in your security.yml file isn’t possible. The “pattern” setting only matches on the route URL, not the parameters so there’s no way to have it selectively trigger when a parameter is present on a URL. So how do you do it? Well as it turns out, there’s a firewall configuration called “reuqest_matcher” which lets you “match” a firewall using a service. Just create a service that extends the RequestMatcherInterface, implment a “matches” function, and then add the class as a service.

Our code for the service ended up looking like:

And then the actual firewall configuration ends up being:

You don’t need a “pattern” setting anymore since the “matches” function supersedes it. Anyway, let me know if you have any questions!

Posted In: PHP, Symfony

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I was building out an API test console a few days ago and realized I’d never actually looked into how to grab all available routes in Symfony2. The “console” is basically a form with a select box and textarea that lets you “ping” the REST API routes in one of our applications. To make this work, I wanted to traverse all the registered routes, filter for the ones that contained “api_”, and then generate dummy URLs for those routes.

I searched around a bit for how to grab all the registered routes and the only link seems to be https://gist.github.com/hubgit/3380250 Unfortunately, if you try and use the code you’ll discover that “getPattern” no longer exists in the CompiledRoute class. It looks like it’s been replaced by getPathVariables

So, working code to generate a list of route names and “dummy” URLs for you API routes ends up looking like:

Posted In: PHP, Symfony

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One of the nicest features of Symfony2 is the Request/Response paradigm for processing a HTTP request and then sending a response back to a client. At a high level, Symfony’s HttpFoundation component provides an object oriented abstraction to easily deal with HTTP requests and generate responses to send back to a client. Assuming application code correctly uses HttpFoundation, it will only interact with request variables through the Request class, as opposed to $_REQUEST, and only send output using the Response class, as opposed to an “echo”. Because of this contract, the framework as a whole makes it easy to manipulate responses before they’re sent back to a client.

A typical use case that leverages this would be logging API responses before they’re sent back to a client. As much as an API might be RESTful, at some point it’s easier to debug things when you can see the responses that clients have been receiving. OK great so how do you do it? It’s actually pretty straightforward, just create a class to receive the “kernel.terminate” event and register it as a service with the appropriate tags:

And then create the class where you want to manipulate or log the requests:

And that’s about it!

Note: Per Andras’ comment below the event has been switched to “kernel.terminate”.

Posted In: Symfony

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On a few of our projects we have a few different needs to either queue items to be processed in the background or we need a single request to be able to process something in parallel. Generally we use Gearman and the GearmanBundle. ┬áLet me explain a few different situations where we’ve found it handy to have Gearman around.

Background Processing

Often we’ll need to do something which takes a bit more time to process such as sending out a couple thousand push notifications to resizing several images. For this example lets use sending push notifications. You could have a person sit around as each notification is sent out and hope the page doesn’t timeout, however after a certain number of notifications, not to mention a terrible user experience, this approach will fail. Enter Gearman. With Gearman you are able to basically queue the event that a user has triggered a bunch of notifications that need to be processed and sent.

What we’ve done above is sent to the Gearman server a job to be processed in the background which means we don’t have to wait for it to finish. At this point all we’ve done is queued a job on the Gearman server, Gearman itself doesn’t know how to run the actual job. For that we create a ‘worker’ which reads jobs and processes them:

The worker will consume the job and then process it as it sees fit. In this case we just loop over each user ID and send them a notification.

Parallel Processing

One one of our applications users can associate their account with multiple databases. From there we go through each database and create different reports. On some of the application screens we let users poll each of their databases and we aggregate the data and create a real time report. The problem with doing this synchronously is that you have to go to each database one by one, meaning if you have 10 databases and each one takes 1 seconds to get the data from, you have at least ten seconds the user is waiting around; this doesn’t go well when you have 20 databases and so on. Instead, we use Gearman to farm out the task of going to each database and pull the data. From there, we have the request process total up all the aggregated data and display it. Now instead of waiting 10 seconds for each database, we farm out the work to 10 workers, wait 1 second and then can do any final processing and show it to the user. In the example below for brevity we’ve just done the totaling in a controller.

What we’ve done here is created a job for each connection. This time we add them as tasks, which means we’ll wait until they’ve completed. On the worker side it is similar to except you return some data, ie `return json_encode(array(‘total’=>50000));` at the end of the the function.

What this allows us to do is to farm out the work in parallel to all the databases. Each worker runs queries on the database, computes some local data and passes it back. From there you can add it all together (if you want) and then display it to the user. With the job running in parallel the number of databases you can process is no longer limited on your request, but more on how many workers you have running in the background. The beauty with Gearman is that the workers don’t need to live on the same machine, so you could have a cluster of machines acting as ‘workers’ and be able to process more database connections in this scenario.

Anyways, Gearman has really made parallel processing and farming out work much easier. As the workers are also written in PHP, it is very easy to reuse code between the frontend and the workers. Often, we’ll start a new report without Gearman; getting logic/fixing bugs in a single request without the worker is easier. After we’re happy with how the code works, we’ll move the code we wrote into the worker and have it just return the final result.

Good luck! Feel free to drop us a line if you need any help.

Posted In: PHP, Symfony

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Last week, we were looking to setup one of our Symfony2 projects to use a master/slave MySQL configuration. We’d looked into using the MasterSlaveConnection Doctrine2 connection class, but unfortunately it doesn’t really work the way you’d expect. Anyway, the “next best” way to set up master/slave connections seemed to be creating two separate EntityManagers, one pointing at the master and one at the slave. Setting up the Doctrine configurations for this is pretty straightforward, you’ll end up with YAML that looks like:

At face value, it looked like everything was working fine but it turns out they weren’t – the FOSUserBundle entities weren’t getting properly setup on the slave connection. Turns out, because FOSUserBundle uses Doctrine2 superclasses to setup it’s fields there’s no way to natively use FOSUserBundle with multiple entity managers. The key issue is that since the UserProvider checks the class of a user being refreshed, you can’t just copy the FOSUserBundle fields directly into your entity:

So how do you get around this? Turns out, you need to add a custom UserProvider to bypass the instance class check. My UserProvider ended up looking like:

And then the additional YAML configurations you need are:

The last step is copying all the FOSUserBundle fields directly into your User entity and update it to not extend the FOSUserBundle base class. Anyway, that’s it – two EntityManagers and one FOSUserBundle.

Posted In: Symfony

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