php-consul-api-bundle

Bundle to enable usage of dcarbone/php-consul-api inside of a Symfony 4 project

Installation

In your composer.json file:

{
    "require": {
        "dcarbone/php-consul-api-bundle": "1.0.*"
    }
}

Default Configuration

There will always be at least one registered Consul service using the standard Consul environment variables. If you wish to use this, at the very least CONSUL_HTTP_ADDR should be defined.

This is also the default target of the consul_api.default alias.

If you want to override just host and keep other params default, use:

consul_api:
    backends: dev.local:8500

Specify default backend

You may optionally override the default configuration with one of the named configurations you have specified as such:

consul_api:
    default_configuration: nifty_name

Named Configurations

If you wish to connect to multiple Consul agents, or just want to have things named differently, you may optionally configure them under the consul_api configuration namespace.

The available configuration parameters are:

addr
scheme
datacenter
wait_time
http_auth
token
ca_file
client_cert
client_key
insecure_skip_verify
token_in_header
http_client
resolve_env
- enabled
- cache

As an example:

consul_api:
    backends:
        nifty_name:
            addr:                   hostname.domain.woot
            scheme:                 https
            insecure_skip_verify:   false
            http_client:            ~ # Enter service name of GuzzleHttp\ClientInterface compatible http client you wish to use
            resolve_env:
                enabled: true       # allow this backend to resolve %env(consul_nifty_name:variable)% within container config
                cache: 60           # cache for a minute results

This will create a new service named consul_api.nifty_name with the specified configuration options.

Environment variables resolving

syntax

Sometimes you don't want to use consul-template because change of environment variables require cache-warmup. This bundle allows you to inject parameters into container just like pure envs:

parameters:
    my_database_dsn: '%env(consul:credentials__db_connection)%'

Syntax:

%env(consul[_<backend name>]:<path with "__" instead of "/">)%

This syntax is processed just like pure environment variables, so the case:

parameters:
    %env(consul_ohai)%: test
    
services:
    
    MyNamespace\Class:
        arguments:
            - '%env(consul_ohai)%'

is processed as well.

caching

If you provide PSR-6 compatible package (symfony/cache is supported out-of-the-box), this bundle is capable of caching results in specified pool (or provided one). Provided the package is installed and you define a number or just set cache flag of backend to true, the bundle will use PhpFilesAdapter. Number specifies TTL, but you are also able to provide very own implementation of caching as long as it implements CachePoolInterface.

To use own backend, define service:

services:
    app.envs_cache:
        class: App\Cache\Envs

and tell you're going to use this:

consul_api:
    backends:
        default:
            resolve_env:
                cache: 'app.envs_cache'

And let the music play.

Overrides

Also, you may override any part of this bundle using Decorate feature of Symfony's DI container. For example, you want just to adjust TTL of cache item: decorate the consul_api.cache_persister service (keep in mind the PersisterInterface) and play freely with decorateItem method:

# app/config/services.yml

services:
    app.my_service:
        decorates: consul_api.default.cache_persister
        class: App\Consul\CachePersister

<?php
namespace App\Consul;

use DCarbone\PHPConsulAPIBundle\Cache\PersisterInterface;
use DCarbone\PHPConsulAPIBundle\Cache\Persister;
use Psr\Cache\CacheItemInterface;

class CachePersister implements PersisterInterface {
    
    protected $parent;
    
    public function __construct(Persister $parent){
        $this->parent = $parent;
    }
    
    public function get(string $name, string $prefix = null){
        return $this->parent->get($name, $prefix);
    }
    
    public function set(string $name, $value = null, string $prefix = null){
        return $this->parent->set($name, $value, $prefix);
    }
    
    public function decorateItem(CacheItemInterface $item, string $prefix = null){
        $item->expiresAfter(86400);
    }  
}

And that's all.

PS. Extending DependencyInjection\EnvVarProcessor has almost no point — its purpose is to tell Symfony that custom prefixes are available and fetch data from adapters. Whole main work is done under particularProcessor\Adapter.

Twig Integration

If you are using Twig and TwigBundle in your Symfony app, there are a few functions exposed to you. You can see the full list here: PHPConsulAPIExtension.

ConsulBag

If you have multiple named configurations present and want to be able to access them all, one possible way is to utilize the ConsulBag service. It is defined as consul_api.bag

er1z / php-consul-api-bundle