feat: link uuid + increase counter concurrently

db/migrations/20240512214223_create_links.sql

@@ -1,10 +1,10 @@
 -- +micrate Up
 -- SQL in section 'Up' is executed when this migration is applied
 CREATE TABLE links (
-	id INTEGER PRIMARY KEY AUTOINCREMENT,
+	id TEXT PRIMARY KEY NOT NULL,
 	slug VARCHAR(100) UNIQUE NOT NULL,
 	url TEXT NOT NULL,
-	click_counter INTEGER DEFAULT 0,
+	click_counter INTEGER NOT NULL DEFAULT 0,
 	created_at INTEGER DEFAULT CURRENT_TIMESTAMP NOT NULL,
 	updated_at INTEGER DEFAULT CURRENT_TIMESTAMP NOT NULL
 );

src/controllers/link.cr

@@ -1,3 +1,5 @@
+require "uuid"
+
 require "../lib/controller.cr"
 
 module App::Controllers::Link
@@ -11,6 +13,7 @@ module App::Controllers::Link
       raise App::BadRequestException.new(env) if !url #TODO: return url "required field" error message
 
       link = Link.new
+      link.id = UUID.v4().to_s
       link.url = url.to_s
       link.slug = Random::Secure.urlsafe_base64(4)
 
@@ -36,11 +39,33 @@ module App::Controllers::Link
       link = Database.get_by(Link, slug: slug)
       raise App::NotFoundException.new(env) if !link
 
-      #TODO: update click_counter
+      spawn do
+        link.click_counter = link.click_counter! + 1
+
+        changeset = Database.update(link)
+        if changeset.errors.any?
+          Log.error { "Increase click counter failed: #{changeset.errors}"}
+        end
+      end
 
       env.redirect link.url!
     end
   end
 
-  #TODO: update, delete, list links
+  class Get < App::Lib::BaseController
+    include App::Models
+    include App::Lib
+
+    def call(env)
+      id = env.params.url["id"]
+
+      link = Database.get(Link, id)
+      raise App::NotFoundException.new(env) if !link
+
+      response = {"data" => App::Serializers::Link.new(link) }
+      response.to_json
+    end
+  end
+
+  #TODO: update, delete
 end

src/models/link.cr

@@ -4,9 +4,10 @@ require "crecto"
 module App::Models
   class Link < Crecto::Model
     schema :links do
+      field :id, String, primary_key: true
       field :slug, String
       field :url, String
-      field :click_counter, Int64
+      field :click_counter, Int64, default: 0
     end
 
     validate_required [:slug, :url]

src/routes.cr

@@ -13,6 +13,10 @@ module App
     Controllers::Link::Index.new.call(env)
   end
 
+  get "/api/links/:id" do |env|
+    Controllers::Link::Get.new.call(env)
+  end
+
   post "/api/links" do |env|
     Controllers::Link::Create.new.call(env)
   end

src/serializers/link.cr

@@ -9,8 +9,10 @@ module App::Serializers
 
     def to_json(builder : JSON::Builder)
       builder.object do
-        builder.field("origin", @link.url)
+        builder.field("id", @link.id)
         builder.field("link", "#{ENV["APP_URL"]}/#{@link.slug}")
+        builder.field("clicks", @link.click_counter)
+        builder.field("origin", @link.url)
       end
     end
   end