feat implement etcd client

[GridexX]

Overall explanation of your work :

We implemented 6 methods for the ETCD_client :

• PUT : insert a couple key/value
• GET : find a value for one key*
• PATCH : update a previously stored value associated with a key
• DELETE : remove a couple key/value stored
• GET_ALL : return all stored values
• GET_ALL_WITH_PAGINATION : return all value delimited within a range with PaginateRequest object and return them througt a PaginateResult :

  pub struct PaginateRequest {
    limit: usize,
    page: usize
  }
  pub struct PaginateResult {
    pub count: usize,
    pub values: Vec<String>
  }

Structure

Service

Workload service contain all functions to interact with ETCD

Controller

Handle request , call service and return HTTP responses

ETCD

Store ETCD key, value like this : "uuid" => Workload (JSON)

Used libraries

etcd_client : an API for interfacing with etcd. It provides asynchronous client backed by tokio and tonic.

[GridexX]

The tests won't succed as an instance of ETCD should be launched on the computer. Shall I remove them ?

[sameo]

The tests won't succed as an instance of ETCD should be launched on the computer. Shall I remove them ?

Disable them for now, and open an issue to track that regression. Don't remove them please.

[GridexX]

The tests won't succed as an instance of ETCD should be launched on the computer. Shall I remove them ?

Disable them for now, and open an issue to track that regression. Don't remove them please.

Tests disabled for now and issue created : #42

Another problem is that the new version of etcd_client need the package protobuf-compiler for building. I have created another issue about that and reverse to the 0.9.2 version

[GridexX]

@sameo PR is finnaly ready to be Merged 😄

[GridexX]

@sameo Have removed all unwrap() function and modify the get method to return an option