Add an endpoint to fetch organization workers

Gemfile

@@ -14,6 +14,7 @@ gem "dry-validation", "~> 1.10"
 gem "grape", "~> 1.7"
 gem "grape-entity", "~> 1.0.0"
 gem "grape-swagger", "~> 1.6"
+gem "kaminari", "~> 1.2"
 gem "pg", "~> 1.1"
 gem "puma", "~> 5.0"
 gem "pundit", "~> 2.3.0"

Gemfile.lock

@@ -141,6 +141,18 @@ GEM
     irb (1.6.3)
       reline (>= 0.3.0)
     json (2.6.3)
+    kaminari (1.2.2)
+      activesupport (>= 4.1.0)
+      kaminari-actionview (= 1.2.2)
+      kaminari-activerecord (= 1.2.2)
+      kaminari-core (= 1.2.2)
+    kaminari-actionview (1.2.2)
+      actionview
+      kaminari-core (= 1.2.2)
+    kaminari-activerecord (1.2.2)
+      activerecord
+      kaminari-core (= 1.2.2)
+    kaminari-core (1.2.2)
     loofah (2.19.1)
       crass (~> 1.0.2)
       nokogiri (>= 1.5.9)
@@ -266,6 +278,7 @@ DEPENDENCIES
   grape (~> 1.7)
   grape-entity (~> 1.0.0)
   grape-swagger (~> 1.6)
+  kaminari (~> 1.2)
   pg (~> 1.1)
   puma (~> 5.0)
   pundit (~> 2.3.0)

app/gateways/rest/api.rb

@@ -8,9 +8,13 @@ class API < Grape::API
     helpers(
       Helpers::Authentication,
       Helpers::Validation,
-      Helpers::Authorization
+      Helpers::Authorization,
+      Helpers::Pagination
     )
 
+    PER_PAGE_LIMIT = 100
+    PER_PAGE_DEFAULT = 50
+
     before do
       authenticate!
     end

app/gateways/rest/api/helpers/pagination.rb

@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+module REST
+  class API
+    module Helpers
+      module Pagination
+        include Validation
+
+        def pagination_params!(params)
+          validated = validate!(params, with: ::REST::Validation::Pagination)
+          default_pagination_params.merge(validated)
+        end
+
+        def default_pagination_params
+          {
+            page: 1,
+            per_page: PER_PAGE_DEFAULT
+          }.with_indifferent_access
+        end
+
+        def present_paginated(collection, with:, page:, per_page:)
+          paginated = collection.page(page).per(per_page).order(created_at: :asc)
+          {
+            items: paginated.map { |item| with.new(item).serializable_hash },
+            last_page: paginated.total_pages
+          }
+        end
+      end
+    end
+  end
+end

app/gateways/rest/api/organizations.rb

@@ -26,6 +26,7 @@ def find_requested_organization!
         mount Delete
 
         namespace(:shifts) { mount Shifts }
+        namespace(:workers) { mount Workers }
       end
     end
   end

app/gateways/rest/api/organizations/shifts.rb

@@ -12,6 +12,7 @@ def select_shifts(filters)
               .for_organization(requested_organization)
               .between(from, to)
               .chronologically
+              .serial
           end
         end
 
@@ -24,7 +25,7 @@ class Contract < Dry::Validation::Contract
           end
 
           rule(:from, :to) do
-            next if values[:to] - values[:from] > MAX_PERIOD.days
+            next if (values[:to] - values[:from]) <= MAX_PERIOD
 
             key(:period).failure(I18n.t!("rest.api.organizations.shifts.errors.long_period", period: MAX_PERIOD))
           end

app/gateways/rest/api/organizations/workers.rb

@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+module REST
+  class API
+    class Organizations
+      class Workers < Base
+        desc "Get organization workers"
+        get do
+          authorize! requested_organization, to: :view_workers, with: OrganizationPolicy
+          pagination_params!(params) => { page:, per_page: }
+          present_paginated(requested_organization.workers, page:, per_page:, with: Serialization::Worker)
+        end
+      end
+    end
+  end
+end

app/gateways/rest/validation/pagination.rb

@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+module REST
+  module Validation
+    class Pagination < Dry::Validation::Contract
+      params do
+        optional(:page).filled(:integer, gteq?: 1)
+        optional(:per_page).filled(:integer, gteq?: 1, lteq?: REST::API::PER_PAGE_LIMIT)
+      end
+    end
+  end
+end

app/models/shift.rb

@@ -17,6 +17,7 @@ class Shift < ApplicationRecord
   scope :for_worker, ->(worker) { where(worker:) }
   scope :between, ->(from, to) { where(start_at: from.utc..to.utc) }
   scope :chronologically, -> { order(start_at: :asc) }
+  scope :serial, -> { order(created_at: :asc) }
 
   delegate :organization, to: :worker
 

app/policies/organization_policy.rb

@@ -10,5 +10,6 @@ def update?
   end
 
   alias view_shifts? update?
+  alias view_workers? update?
   alias delete? update?
 end