diff --git a/CHANGELOG.md b/CHANGELOG.md
index 29f44a7ee..a3967568f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,7 @@
 - Faraday was downgraded from 1.0 to 0.17 for better compatibility with elasticsearch-ruby 5 (#205 #196)
 - Added [an option](doc/environment.md#ALLOW_INSECURE_HTTP) to allow usage in production without HTTPS
 - Now using node.js instead of therubyracer for building javascript assets
+- Removed dependency to has_secure_token to fix warnings about already initialized constant
 - Fix a bug: when an admin logs on the subscription page, his view is broken
 - Fix a bug: admin's members list shows the same members multiple times
 - Fix a bug: when a new account is created through the sign-up modal, the role is not reported in the StatisticProfile (#196)
diff --git a/Gemfile b/Gemfile
index 3eb93aaca..6c091f384 100644
--- a/Gemfile
+++ b/Gemfile
@@ -132,7 +132,6 @@ gem 'openlab_ruby'
 
 gem 'api-pagination'
 gem 'apipie-rails'
-gem 'has_secure_token'
 
 # XLS files generation
 gem 'caxlsx'
diff --git a/Gemfile.lock b/Gemfile.lock
index 486eaf098..f6cbe0f62 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -179,8 +179,6 @@ GEM
       raabro (~> 1.1)
     globalid (0.4.2)
       activesupport (>= 4.2.0)
-    has_secure_token (1.0.0)
-      activerecord (>= 3.0)
     hashdiff (1.0.1)
     hashery (2.1.2)
     hashie (4.1.0)
@@ -484,7 +482,6 @@ DEPENDENCIES
   foreman
   forgery
   friendly_id (~> 5.1.0)
-  has_secure_token
   icalendar
   jbuilder (~> 2.5)
   jbuilder_cache_multi
diff --git a/app/models/open_api/client.rb b/app/models/open_api/client.rb
index 2dc2bf231..a9815eaf7 100644
--- a/app/models/open_api/client.rb
+++ b/app/models/open_api/client.rb
@@ -1,9 +1,29 @@
+# frozen_string_literal: true
+
+# OpenAPI::Client keeps track of the authorized accesses to the 3-rd party API (aka. OpenAPI)
 class OpenAPI::Client < ApplicationRecord
   has_many :calls_count_tracings, foreign_key: :open_api_client_id, dependent: :destroy
-  has_secure_token
+
   validates :name, presence: true
+  validates_uniqueness_of :token
+
+  before_create :set_initial_token
 
   def increment_calls_count
     update_column(:calls_count, calls_count+1)
   end
+
+  def regenerate_token
+    update_attributes(token: generate_unique_secure_token)
+  end
+
+  private
+
+  def set_initial_token
+    self.token = generate_unique_secure_token
+  end
+
+  def generate_unique_secure_token
+    SecureRandom.base58(24)
+  end
 end