I've a very basic question which drives me nuts. I maintain my own little framework. I can configure the framework with a YAML/JSON/XML/whatever settings file. The framework uses also a cache (any of memcached/couchbase/whatever even file based caching if no caching server is installed).
So no I've the following problem: I like to cache my settings parsed from the settings file in the cache but I would like to define the cache type used for that in the settings file.
What would be a proper solution for this? I can't imagine how I should manage this which leeds me to the thought that I probably have a very basic design / architecture error in my framework. Is there any solution at all?
Well as my experience from Symfony1 and Symfony2 goes, cache as much as you can.
In their production environment everything is cached, so you would run into your problem that the cache type is described in the settings file which is itself cached.
The proper solution to this is: As in Symfony: Delete the cache in prod, once you made changes to settings.
For dev the settings are always re-read as you do not profile in debug, so ease of development is more important that bootstrap time.
I recommend splitting this like symfony did.
For prod your settings are seldomly changed so parsing a file that can be cached is wasted resources and speed is typically priority 1 in prod.
Edit: Your options regarding the order of bootstrapping:
Always read settings first then decide which cache you will need.
Use a settings configuration cache that is hard coded (e.g file based)
I recommend using option 2. Your framework is cache agnostic as this can be configured, which is good but for basic settings of your framework you simply do not need that. You don't want to setup different cache mechanisms like memcache, sql etc just for basic settings.
Symfony solves this by the most effective way, as it provides a default cache generation for settings and this is simply a php file. Thats all. When symfony loads settings it looks for a certain file to include, if it does not exist, symfony caches it by creating plain php and then reads it.
You can determine the file type from the file extension. Then you can read the cache type and create a cache. The cache should be a singleton.
For the creation of the cache I would use an abstract factory, which implementation is dependent on the file type. The appropriate implementation of the abstract factory then can read the settings file and create the right cache.
Related
I'm creating an app in Phalcon which contains a theme manager. A theme is nothing more that a collection of .scss and .volt files. Naturally, these .scss are built before being used.
I'm been testing Phalcon's assets manager. Apart from some difficulties creating custom filters, etc, I started wondering: why would someone build their files all the time? This would make each request much slower. Does Phalcon cache these assets?
Furthermore, when developing themes or doing a lot of frontend work it is useful to watch the source sass files for changes. Is this possible in Phalcon?
According to manual using ->setTargetPath() on assets collection makes it possible to save all selected files into one location. If you have some scripts you always include to your page, you can marge them to one file, and meantime minify thanks to filters filters. Code snipped would be somewhat like that:
$controller->assets->collection('jsGlobal')
->addJs('libs/jquery.js', true)
->addJs('libs/jquery-ui.js', true)
->setTargetPath('js/global.js')
->setTargetUri('js/global.js')
->join(true)
->addFilter(new \Phalcon\Assets\Filters\Jsmin());
You may want to check if script it already built under that js/global.js location to prevent from building it over and over again on production. This way, when making your deploy script you can just implement deletion of certain files on your production server.
Projects I'm working on uses less. We installed \lessc library to manage to keep in repository only .less files.
And again, in development mode we're not even checking if file was changed - we assume is was and are recompiling it just always. For production purposes, PHP is written to check if certain scripts does exist and is compiling .less only if they dont.
I am solving a problem: I have a ZF2 Skeleton application which runs fine, service manager, db adapter, routing, everything is fine. But what I need to solve is how, when or how better load some configuration (settings) from database?
The point is (AFAIK) to have the Zend configs that are not visible nor editable from outside (or let's say via administration). But I need to have the ability to administer many configuration settings - and these should be loaded also on the startup (bootstrap, whatever). These settings could be managing e.g. widgets displaying (let's assume that almost every block on the website is controlled by widget - view helper - and I have to decide - via configuration - whether to display that widget or with what additional settings).
What I would need to help with is how to manage this configuration that will be loaded from DB.
should I merge it with Zend config?
should I load it in module's onBoostrap?
should I use better solution (what)?
I was thinking of having editable PHP config file (that will Zend simply load with other config files) so that administering these settings would lead to reading from and writing to a file but this is really a bad idea as there is possibility of more simultaneous edits for which purposes the database handles this far better.
Your module.php should have a function getConfig() which returns an array. You should be able to modify it in such a way to fetch your config key/values from the database.
I'm trying to implement the whole page cache in my website. (Just like stackoverflow). I have already implemented the Output Cache, but my friend told me that stackoverflow uses redis as their cache layer and I'm confused about the redis part.
Is redis the same as outputcache? Can I implement outputcache by using redis? (For yii developers, I'm using Yii's outputcache).
Thanks!
Yii's output cache will store the cached content using the active cache component, which can be CDummyCache/CDbCache/CApcCache/CFileCache/CMemCache, etc(what you set in the config file under the components area).
As it stands right now, there is no official CRedisCache component, but there is this extension: http://www.yiiframework.com/extension/rediscache/ which might help you.
Also, since Redis is key/value store and a bit more(though you won't use that bit more at all i guess) you can give CMemCache a try(having in mind you have memcache php extension and memcached daemon installed on your server).
L.E: i also found this for you: https://github.com/phpnode/YiiRedis which seems very neat.
I'm working myself through creating an app using Zend Framework 2 and one of the features I really liked was having the ability to set PHP settings based on the environment (mostly enabling the error displays in the devel environment). As far as I can tell from my limited research this feature doesn't yet (or won't) exist and you have to create a custom solution for it.
Am I wrong or is this the only solution as of ZF 2.0.2?
You're correct, as of 2.0.2, there is no "built-in" solution for this in ZF2. If you're using PHP config files, you can simply put the ini_set() calls there. I've outlined methods for doing environment specific configuration files on my blog: http://blog.evan.pro/environment-specific-configuration-in-zend-framework-2
At a quick glance, the solution on the link you provided should still work as of 2.0.2. Personally, I'd just put the ini_set() calls in my configs, as I said, instead of attaching an extra listener to the bootstrap event, an extra check for the config key, and a foreach loop, but that's the beauty of ZF2: If you're looking for an easy way to provide PHP settings via the config, there's a module for that!
I need to update source files (pull and update from the repository) in my production server, run migrations, and regenerate cached assets.
Is there any mechanism in Symfony 2 to do this safely? Like putting the site into 'maintainance mode' (which should throw a 503) or something?
I've just found a Bundle for Symfony 2, which offers you 2 extra-commands in the console to put your application into maintenance mode.
Here you go: https://github.com/lexik/LexikMaintenanceBundle
I've been trying to decide how I would implement this. On one hand, Symfony2 provides decent prod caching, so if you're not destructively modifying your database schema (removing columns or tables, etc), you can probably get away with just changing the schema, deploying from your repo, then clearing your prod cache. That's how I handle things most of the time.
On the other hand, if you DO want to go into maintenance mode, you'll want a solution that has minimal load on the framework (ie, you probably don't want to fire up the kernel), or you're defeating the purpose anyway: taking the load off the framework while you muck with things.
If it were me, I'd probably write a simple maintenance script that just sets a 503 header, maybe serves up some static html (pregenerated from my site templates) and sends it back to the user, then use some conditional logic in my app.php to use that when I should be in maintenance mode. It's ugly, but it works.
Not sure how to go about this for a bigger site where a user could be in the middle of some kind of transaction (shopping for instance) but for a smaller site could you not just use a .htaccess file (the one in the web directory assuming that is your root) to redirect to some maintenance page instead of into app.php.
I can recommend using deployer (http://deployer.org/) to deploy your Symfony2 application. This way you dont need a maintenance page. The tool ships with a symfony2 and symfony3 template already included.
It generates your assets, warms up the cache and keeps track of your release directories. It's easy to roll back to a previous release also.
there is a "current"-symlink which always points to your current release directory. If a release deployment is complete this link updates to the newly created release directory.
Regarding doctrine migrations you need to write a custom task for that.
Please look at capifony http://capifony.org/
It has excellent support for Symfony2.