DEV Community: Thai Nguyen Hung

opencode context manager

Thai Nguyen Hung — Tue, 16 Sep 2025 02:21:15 +0000

I have created a CLI tool named "occtx" for switching between different opencode configurations. It supports both global and project level.

Feel happy to hear your feedbacks.

opencode context manager

Thai Nguyen Hung — Tue, 16 Sep 2025 02:05:18 +0000

I have created a CLI tool named "occtx" for switching between different opencode configurations. It supports both global and project level.

Feel happy to hear your feedbacks.

Laravel "Chunk" ... be careful

Thai Nguyen Hung — Fri, 19 Jun 2020 03:11:30 +0000

Laravel "chunk" method is widely used to split large query into smaller chunks when processing large database. But there is a trick if the attribute used in query would be changed in call back function. It is easy to be ignored and thus often be misused.

Problem

Post::where('processed', 0)->chunk(100, function($posts) {
    foreach($posts as $post) {
       $post->processed = 1;
       $post->save();
    }
});

Assumption: the total number of unprocessed posts is 400 (Id is 1 - 400).
The problem is: Only half of the posts are processed.

Analyzation

Each chunk is being fetched via single query with limit and offset. Let’s have a look how chunk works.

In the beginning, unprocessed posts are 400 (Ids 1- 400), for 1st chunk query: select * from `posts` where `processed` = 0 limit 100 offset 0, Ids 1-100 are fetched.

After 1st chunk, unprocessed posts are 300 (Ids 101- 400), for 2nd chunk query: select * from `posts` where `processed` = 0 limit 100 offset 100, Ids 201-300 are fetched.

After 2nd chunk, unprocessed posts is 200 (Ids 101- 200 and 301- 400), for 3rd chunk query: select * from `posts` where `processed` = 0 limit 100 offset 200, bummmm ... none of post is fetched.

The result is: 200 posts are processed, but 200 posts are left unprocessed.

Solution:

"chunkById" is recommended to replace "chunk" in this situation. "chunkById" is similar to "chunk". The only difference is how raw SQL is being constructed. "chunkById" uses id and limit while "chunk" uses limit and offset.
The modified code would be like:

Post::where('processed', 0)->chunkById(100, function($posts) {
    foreach($posts as $post) {
       $post->processed = 1;
       $post->save();
    }
});

When using "chunkById", each chunk query sql sentence would be like below:

1st chunk query: select * from `posts` where `processed` = 0 and `id` > 0 order by id asc limit 100

2nd chunk query: select * from `posts` where `processed` = 0 and `id` > 100 order by id asc limit 100

3rd chunk query: select * from `posts` where `processed` = 0 and `id` > 200 order by id asc limit 100

4th chunk query: select * from `posts` where `processed` = 0 and `id` > 300 order by id asc limit 100

Therefore the fetch result would be 1-100, 101- 200, 201 -300, 301- 400 in sequence, and all of the posts are processed.

Creating a Monorepo with Vue & Laravel by Lerna & Yarn Workspaces

Thai Nguyen Hung — Wed, 17 Jun 2020 04:58:47 +0000

This is the GitHub reposiroty: https://github.com/hungthai1401/universal-monorepo-template

Getting Started

Lerna

First, let’s create a new project and set up Lerna.

mkdir monorepo
cd monorepo
npx lerna init

This creates a package.json file for your project.

{
  "name": "root",
  "private": true,
  "devDependencies": {
    "lerna": "^3.22.1"
  }
}

Add scripts to root package.json

{
  "name": "root",
  "private": true,
  "scripts": {
    "bootstrap": "lerna bootstrap --use-workspaces",
    "start": "lerna run start --parallel",
    "build": "lerna run build --parallel"
  },
  "devDependencies": {
    "lerna": "^3.22.1"
  }
}

You’ll notice a lerna.json file has also been created, as well as a packages folder which will contain our libraries.

{
  "packages": [
    "packages/*"
  ],
  "version": "0.0.0",
  "npmClient": "yarn",
  "useWorkspaces": true
}

We’ll also need to modify our package.json to define where the Yarn workspaces are located.

{
  "name": "root",
  "private": true,
  "workspaces": [
    "packages/*"
  ],
  "devDependencies": {
    "lerna": "^3.22.1"
  }
}

Vue

Installing Vue CLI globally

npm install -g @vue/cli
# OR
yarn global add @vue/cli

Next we have to create a frontend layer in packages directory

cd packages
vue create frontend

Follow steps till become successful, we will go to frontend directory

cd frontend

and modify package.json

{
  "name": "@mono/frontend",
  ...
  "scripts": {
    ...
    "start": "yarn serve"
  },
  ...
}

Laravel

Installing Laravel by issuing the Composer

cd ..
composer create-project --prefer-dist laravel/laravel backend

After successfully, we will go to backend directory

cd backend

and modify package.json

{
  "name": "@mono/backend",
  "version": "0.1.0",
  "private": true,
  "scripts": {
    "start": "php artisan serve"
  }
}

Go to root repository

cd ../..

and install and link all dependencies.

yarn bootstrap

Start all packages

yarn start

Refs:

Lerna: The Monorepo manager
Vue CLI: The full system for rapid Vue.js development
Vue: The frontend layer
Laravel: The backend layer

Use isset() Instead of strlen()

Thai Nguyen Hung — Mon, 15 Jun 2020 01:55:31 +0000

isset() is faster than using strlen() because calling a function is more expensive than using a language construct.
The isset() method is consistently about 6 times faster.

Test to show the speed http://codepad.org/ztYF0bE3

strlen() over 1000000 iterations 7.5193998813629
isset() over 1000000 iterations 0.29940009117126

Refs:

https://www.phpreferencebook.com/tips/use-isset-instead-of-strlen/

Laravel Check If Relationship has Loaded or Not

Thai Nguyen Hung — Mon, 08 Jun 2020 10:11:48 +0000

One of the nice things of Larave is eager loading. Now, sometimes if you need to check whether the model has loaded the eager loading or not, then you need to check with relationLoaded().

Here is my original code.

$users = App\User::with('profile')->first();

Now, I want to check whether $user load the relationship profile or not.

$users = App\User::with('profile')->first();

if ($users->relationLoaded('posts')) {
    // yes, it has been loaded
    // now, place your logic here
}

Laravel use or force index on a query

Thai Nguyen Hung — Thu, 04 Jun 2020 06:49:49 +0000

When you want to use or force index with Query Builder in Laravel, you can do it

$query = SomeModel::query()->getModel()
$query->setTable(DB::raw($query->getTable() . ' USE INDEX(index_name)'))
$results = $query->get();

In complex queries with with() previous solution doesn't work. Better to overwrite base query 'from' value instead:

$query = SomeModel::with('some_relations')...->orderBy();
$query->getQuery()->from(DB::raw($query->getQuery()->from . ' USE INDEX (index_name)'));
// or just
$query->getQuery()->from(DB::raw('`table` USE INDEX (index_name)'));
$results = $query->get();

Hope it will helpful with you.

Laravel N + 1 queries detector

Thai Nguyen Hung — Wed, 03 Jun 2020 08:48:14 +0000

Problem:

My working has many many performance problems. All most of case is N + 1 queries. I have to spent a lot time to find them ...and just feel angry and tired.
There is a packages helpful with you: https://github.com/beyondcode/laravel-query-detector
A thank you to an author for a good package.
But as a developer, I want to make a simple solution by me.

Solution:

After reading Laravel source code, I have found a way to detect N + 1 queries in some lines of code.

class LazyLoadingException extends \Exception
{

}

trait LazyLoadingDetector
{
    /**
     * Get a relationship value from a method.
     *
     * @param  string $method
     *
     * @return mixed
     *
     * @throws \LogicException
     * @throws \LazyLoadingException
     */
    protected function getRelationshipFromMethod($method)
    {
        $modelName = static::class;
        $exception = new LazyLoadingException("Attempting to lazy-load relation '$method' on model '$modelName'");
        if (! app()->isLocal()) {
            logger()->warning($exception->getTraceAsString());
            goto next;
        }

        report($exception);

        next:
        return parent::getRelationshipFromMethod($method);
    }
}

Usage:

class User extends Authenticatable
{
    use LazyLoadingDetector;
}

You will see the report in logs file if attempt N + 1 queries.

P/s:

I am wondering I would publish a simple package.
Please tell me your opinions and give me a star.

Refs:

https://laravel.com/api/5.8/Illuminate/Database/Eloquent/Concerns/HasAttributes.html#method_getRelationshipFromMethod