test: integration link spec

- spec_helper (spec-kemal setup)
- spec_helper (micreate migration)
- create_test_link + get_test_link + delete_test_link helpers
- fix test env variables

spec/spec_helper.cr

@@ -1,2 +1,48 @@
-require "spec"
-require "../src/pa"
+require "uuid"
+
+require "spec-kemal"
+require "micrate"
+
+require "../url-shortener"
+
+Spec.before_suite do
+  Micrate::DB.connection_url = ENV["DATABASE_URL"]
+  Micrate::Cli.run_up
+end
+
+def create_test_user
+  user = App::Models::User.new
+  user.id = UUID.v4.to_s
+  user.name = "Tester"
+  user.api_key = Random::Secure.urlsafe_base64()
+
+  changeset = App::Lib::Database.insert(user)
+  if !changeset.valid?
+    raise "Test user creation failed"
+  end
+
+  user
+end
+
+def create_test_link(user, url)
+  link = App::Models::Link.new
+  link.id = UUID.v4.to_s
+  link.url = url
+  link.slug = Random::Secure.urlsafe_base64(4)
+  link.user = user
+
+  changeset = App::Lib::Database.insert(link)
+  if !changeset.valid?
+    raise "Test link creation failed"
+  end
+
+  link
+end
+
+def get_test_link(link_id)
+  App::Lib::Database.get!(App::Models::Link, link_id)
+end
+
+def delete_test_link(link_id)
+  App::Lib::Database.raw_exec("DELETE FROM links WHERE id = (?)", link_id) # tempfix: Database.delete does not work
+end