We are going to start from where we left in the previous chapter and increment it.

## About JWT { #about-jwt }

JWT means "JSON Web Tokens".

It's a standard to codify a JSON object in a long dense string without spaces. It looks like this:

```
eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c
```

  - 💾 [PostgreSQL](https://www.postgresql.org) als SQL-Datenbank.
- 🚀 [React](https://react.dev) für das Frontend.
  - 💃 Verwendung von TypeScript, Hooks, Vite und anderen Teilen eines modernen Frontend-Stacks.
  - 🎨 [Tailwind CSS](https://tailwindcss.com) und [shadcn/ui](https://ui.shadcn.com) für die Frontend-Komponenten.
  - 🤖 Ein automatisch generierter Frontend-Client.

import okio.Buffer
import okio.ByteString
import okio.ByteString.Companion.toByteString

/**
 * Decodes a multiline string that contains a [certificate][certificatePem] which is
 * [PEM-encoded][rfc_7468]. A typical input string looks like this:
 *
 * ```
 * -----BEGIN CERTIFICATE-----
 * MIIBYTCCAQegAwIBAgIBKjAKBggqhkjOPQQDAjApMRQwEgYDVQQLEwtlbmdpbmVl
 * cmluZzERMA8GA1UEAxMIY2FzaC5hcHAwHhcNNzAwMTAxMDAwMDA1WhcNNzAwMTAx

    for prod and one for tests. However, unlike our other packages, as of this
    writing it has test supersource but no prod supersource.

    GWT happens to use the prod .gwt.xml, so it looks for no supersource for
    tests, either. This causes it to fail to find AtomicLongMapTest.

    Our workaround is to tell GWT that util.concurrent and all other packages

## Overview

* Full-Featured ORM
* Associations (Has One, Has Many, Belongs To, Many To Many, Polymorphism, Single-table inheritance)
* Hooks (Before/After Create/Save/Update/Delete/Find)
* Eager loading with `Preload`, `Joins`
* Transactions, Nested Transactions, Save Point, RollbackTo to Saved Point
* Context, Prepared Statement Mode, DryRun Mode

    private final List<Thread> hooks = new ArrayList<>();

    @Override
    synchronized void addShutdownHook(Thread hook) {
      hooks.add(hook);
    }

    synchronized void shutdown() throws InterruptedException {
      for (Thread hook : hooks) {
        hook.start();
      }
      for (Thread hook : hooks) {
        hook.join();
      }
    }
  }

    - 💾 [PostgreSQL](https://www.postgresql.org) como banco de dados SQL.
- 🚀 [React](https://react.dev) para o frontend.
    - 💃 Usando TypeScript, hooks, Vite, e outras partes de uma _stack_ frontend moderna.
    - 🎨 [Tailwind CSS](https://tailwindcss.com) e [shadcn/ui](https://ui.shadcn.com) para os componentes de frontend.
    - 🤖 Um cliente frontend automaticamente gerado.

// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package dns

import (
	"path"
	"strings"

	"github.com/miekg/dns"
)

// msgPath converts a domainname to an etcd path. If s looks like service.staging.skydns.local.,
// the resulting key will be /skydns/local/skydns/staging/service .
func msgPath(s, prefix string) string {
	l := dns.SplitDomainName(s)
	for i, j := 0, len(l)-1; i < j; i, j = i+1, j-1 {

    - 🔍 [Pydantic](https://docs.pydantic.dev): FastAPI에 의해 사용되는, 데이터 검증과 설정관리.
    - 💾 [PostgreSQL](https://www.postgresql.org): SQL 데이터베이스.
- 🚀 [React](https://react.dev): 프론트엔드.
    - 💃 TypeScript, hooks, [Vite](https://vitejs.dev) 및 기타 현대적인 프론트엔드 스택을 사용.
    - 🎨 [Chakra UI](https://chakra-ui.com): 프론트엔드 컴포넌트.
    - 🤖 자동으로 생성된 프론트엔드 클라이언트.
    - 🧪 E2E 테스트를 위한 [Playwright](https://playwright.dev).
    - 🦇 다크 모드 지원.

    - 🔍 [Pydantic](https://docs.pydantic.dev) FastAPI的依赖项之一，用于数据验证和配置管理。
    - 💾 [PostgreSQL](https://www.postgresql.org) 作为SQL数据库。
- 🚀 [React](https://react.dev) 用于前端。
    - 💃 使用了TypeScript、hooks、[Vite](https://vitejs.dev)和其他一些现代化的前端技术栈。
    - 🎨 [Chakra UI](https://chakra-ui.com) 用于前端组件。
    - 🤖 一个自动化生成的前端客户端。
    - 🧪 [Playwright](https://playwright.dev)用于端到端测试。
    - 🦇 支持暗黑主题（Dark mode）。