Run, config, run: how we speed up deploying configs in Badoo

Configuration files (configs) are an integral part of most applications, but, as practice shows, this is not the most popular topic for discussion. Most often, conversations about configs are limited to discussing working with them directly in the code: how to structure them, use environment variables or not, where to store passwords, etc. 

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if (\DownChecker\Host::isDisabled($host)) {
   $this->errcode = self::ERROR_CONNECT_FAILED;
   return false;
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

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AutoConfig

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$record = \AutoConfig\AutoConfigRecord::initByKeyData('myKey', 'Hello, Habr!', 'Eugene Tupikov');
$storage = new \AutoConfig\AutoConfigStorage();
$storage->deployRecord($record);
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

$reader = new \AutoConfig\AutoConfigReader();
$config = $reader->getFromCurrentSpace('myKey');
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

$storage = new \AutoConfig\AutoConfigStorage();
$storage->removeKey('example');
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

Consul watch

Consul watch HTTP API, .

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curl -X PUT --data 'hello, habr!' http://127.0.0.1:8500/v1/kv/habr-key
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

curl -v http://127.0.0.1:8500/v1/kv/habr-key
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

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...
...
< X-Consul-Index: 266834870
< X-Consul-Knownleader: true
...
...
<
[
  {
    "LockIndex": 0,
    "Key": "habr-key",
    "Flags": 0,
    "Value": "aGVsbG8sIGhhYnIh",
    "CreateIndex": 266833109,
    "ModifyIndex": 266834870
  }
]
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

X-Consul-Index index

curl http://127.0.0.1:8500/v1/kv/habr-key?index=266834870

  ...


      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

index API , -.

curl -X PUT --data 'updated value' http://127.0.0.1:8500/v1/kv/habr-key
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

, ( Value ModifyIndex):

[
  {
    "LockIndex": 0,
    "Key": "habr-key",
    "Flags": 0,
    "Value": "dXBkYXRlZCB2YWx1ZQ==",
    "CreateIndex": 266833109,
    "ModifyIndex": 266835734
  }
]
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

consul watch -type=key -key=habr_key <handler>
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

Consul watch .

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consul watch -type=keyprefix -prefix=auto_config/ <handler>
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

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return [
    'value' => [
        'version' => 437036,
        'keys' => [
            'my/awesome/key' => '80003ff43027c2cc5862385fdf608a45',
            ...
            ...
        ],
        'created_at' => 1612687434
    ]
]
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

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