Project show and edit

app/controllers/projects_controller.rb

@@ -0,0 +1,30 @@
+class ProjectsController < ApplicationController
+  before_action :fetch_project!, only: %w[show edit update destroy]
+
+  def index
+    @projects = Project.all
+  end
+
+  def show
+  end
+
+  def edit
+  end
+
+  def update
+    if @project.update(params.expect(project: %i[code name description]))
+      redirect_to @project
+    else
+      render :edit, status: :unprocessable_entity
+    end
+  end
+
+  def destroy
+  end
+
+  private
+
+  def fetch_project!
+    @project = Project.find_by!(code: params[:id])
+  end
+end