CODE EXAMPLE FOR PHP

laravel update method

 public function update(UpdatePostRequest $request, Post $post)
    {
        $request->validate([
        //unique:table,column,id
        "title" => "required|unique:posts,title,".$this->route('post')->id."|min:5",
        "description" => "required|min:15",
        "cover" => "nullable|file|mimes:jpeg,png|max:5000"
        ]);

        $post->title = $request->title;
        $post->slug = Str::slug($request->title);
        $post->description = $request->description;
        $post->excerpt = Str::words($request->description,50);

        if($request->hasFile('cover')){

//            delete old cover
            Storage::delete("public/cover/".$post->cover);

//            upload new cover
            $newName = "cover_".uniqid()."_".$request->file('cover')->extension();
            $request->file('cover')->storeAs("public/cover",$newName);

//            save to table
                $post->cover = $newName;
        }

            $post->update();

        return redirect()->route('post.detail',$post->slug)->with('status','Post Updated');
    }