Dalisama.Extensions.Configuration.Consul 1.0.0

Dalisama.Extensions.Configuration.Consul

Hi! As a rule of thumb, it's always better to separate your application package and your configuration, especially when working with docker or/and microservice, you need to ship them separately. One way to ship your configuration is via consul that offer you the opportunity to deliver you configuration via API.

If you implement your own API to deliver configuration, please use this package Dalisama.Extensions.Configuration

Example

I am a big believer of learning by example so:

Get consul up and running

the easiest way to do this is by using docker:

after installing docker in your workstation, run this command to get the latest consul image:

$ docker pull consul

and to run it try:

$ docker run \

-d \

-p 8500:8500 \

-p 8600:8600/udp \

--name=badger \

consul agent -server -ui -node=server-1 -bootstrap-expect=1 -client=0.0.0.0

in your browser go to: http://localhost:8500/ui/dc1/kv to make sure that consul work right.

Now, using this command let us add our configuration to consul to use it later:

curl --request PUT  --data value1  http://127.0.0.1:8500/v1/kv/Example/MyKeys/key1

curl --request PUT  --data value2  http://127.0.0.1:8500/v1/kv/Example/MyKeys/key2

curl --request PUT  --data value3  http://127.0.0.1:8500/v1/kv/Example/MyKeys/key3

curl --request PUT  --data value4  http://127.0.0.1:8500/v1/kv/Example/MyKeys/key4

to be sure that you did configure consul right just go to:

http://localhost:8500/ui/dc1/kv/Example/MyKeys/

Example/MyKeys this is the path of the configuration in consul.

Consume the configuration

Now you need to run this web application from your visual studio or using command line Dalisama.Extensions.Configuration.Consul.Example.

after that using your browser go to:

https://localhost:5001/API/Example

and you will get

[
  {
    "key1": "value1",
    "key2": "value2",
    "key3": "value3",
    "key4": 4
  },
  {
    "key1": "value1",
    "key2": "value2",
    "key3": "value3",
    "key4": 4
  }
]

now let us try this command to change our configuration without exiting our application

curl --request PUT  --data new_value1  http://127.0.0.1:8500/v1/kv/Example/MyKeys/key1

curl --request PUT  --data new_value2  http://127.0.0.1:8500/v1/kv/Example/MyKeys/key2

curl --request PUT  --data new_value3  http://127.0.0.1:8500/v1/kv/Example/MyKeys/key3

curl --request PUT  --data new_value4  http://127.0.0.1:8500/v1/kv/Example/MyKeys/key4

now let 's refresh our URL:

[
  {
    "key1": "new_value1",
    "key2": "new_value2",
    "key3": "new_value3",
    "key4": 4
  },
  {
    "key1": "value1",
    "key2": "value2",
    "key3": "value3",
    "key4": 4
  }
]

And voilà the configuration gets a refreshed. To be more accurate the first element of the array did. but why?

[HttpGet]

public List<Keys> Get([FromServices] IOptionsSnapshot<Keys> option1, [FromServices] IOptions<Keys> option2)

{

return new List<Keys> { option1.Value, option2.Value };

}

You can notice that the first element is injected as IOptionsSnapshot that is why it did change but the second is element is injected as IOptions that's why it didn't change.

So how to integrate the library, simply put:

In the startup.cs:

public Startup(IConfiguration configuration)

{

Configuration = configuration;

Configuration = (IConfiguration)new ConfigurationBuilder().AddApiConfiguration(options =>

{

options.ApiUri = "http://localhost:8500/v1/kv/";

options.KeyPath = @"Example";

options.ReloadOnChange = true;

options.IgnoreSSL = true;

}).Build();

}

For authentication you need to set options.Headers with the token:

options.Headers = new Dictionary<string, string>
{  // for authentication you can use one of those two but not both, don't be creedy
// ["X-Consul-Token"]="token"
// [Authorization]="Bearer <token>"
};

Finally, you need to inject your configuration mapping:

services.Configure<Keys>(Configuration.GetSection("MyKeys"));