docs: translate the PipeCD plugin development book to English

[vanshika2720]

docs: Translate the Japanese PipeCD Plugin Development Book into English

Description

This Pull Request translates the comprehensive Japanese PipeCD Plugin Development Book:

作って学ぶ PipeCD プラグイン

by:

@Warashi

into English.

The translated book is hosted under a newly structured documentation path:

docs/content/en/docs-dev/plugin-development/

and serves as a step-by-step walkthrough and reference guide for developers building custom PipeCD plugins.

As PipeCD continues expanding its pluggable continuous delivery architecture, this book provides an important developer-focused resource covering the complete lifecycle of implementing a custom local file synchronization plugin using the official Go SDK.

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Technical Highlights & Content Breakdown

The translated book consists of:

22 chapters

organized under a new Hugo documentation section.

---

Section Index (_index.md)

Added a new Hugo section index to:

• Configure sidebar navigation weighting (weight: 10)
• Register the landing page for:

Plugin Development Book

under the:

docs-dev

documentation section.

---

Foundational & Architecture Guides (Chapters 1–6)

These chapters introduce:

• Custom plugin stage features
• PipeCD plugin architecture
• SDK structure and responsibilities

Topics include:

• FILE_DIFF
• FILE_SYNC
• FILE_ROLLBACK

and deep dives into:

• StagePlugin
• DeploymentPlugin
• LiveStatePlugin

within PipeCD’s pluggable architecture.

---

Core Development Walkthrough (Chapters 7–16)

Covers complete plugin implementation using the official Go SDK:

github.com/pipe-cd/piped-plugin-sdk-go/pkg/plugin/sdk

Topics include:

• Boilerplate plugin setup
• Implementing the sdk.DeploymentPlugin contract
• Configuration structures:
  • config
  • deployTargetConfig
  • applicationConfig
• Sync pipeline implementations
• PipelineSync
• QuickSync
• Stage execution routing via:

ExecuteStage

---

Engine Implementation & Testing (Chapters 17–20)

Provides a full walkthrough of implementing the local file synchronization engine using Go standard library packages including:

• io/fs
• path/filepath
• os

Detailed implementations include:

• listFiles
• differenceFiles
• isFileContentDifferent
• copyFiles
• removeFiles

Also covers robust implementations for:

• FILE_DIFF
• FILE_SYNC
• FILE_ROLLBACK

including rollback synchronization against:

RunningDeploymentSource

instead of:

TargetDeploymentSource

---

Integration & E2E Testing (Chapters 21–22)

Covers end-to-end local development and testing using:

• Docker Compose
• Local Control Plane setup
• Mock Piped agent registration

Additional topics include:

• Building the plugin binary
• Configuring the plugins block in Piped
• Deploying a Git-backed local application

---

Quality & Compliance Standards Met

Terminological Consistency

All translated terminology was aligned with official PipeCD architecture and documentation standards including:

• Canary Deployments
• Quick Sync
• Pipeline Sync
• Platform Provider
• LogPersister

---

SDK Stability Context

Added technical notes explaining SDK compatibility and architecture context around:

pipedv1 / Pluggable Architecture

and SDK version:

v0.0.0-20250619080234-1ee9423d23c1

Developers are encouraged to cross-reference:

• Go interfaces
• RPC definitions
• Main PipeCD codebase implementations

for long-term compatibility awareness.

---

Code Integrity

Preserved all original:

• Go code blocks
• Directory layouts
• Configuration examples
• Terminal commands

without modification to maintain implementation correctness.

---

Formatting

Verified and formatted all modified files using:

npx prettier --write

to maintain documentation consistency and clean formatting.

---

DCO Compliance

All commits in this branch are signed off in compliance with:

• Developer Certificate of Origin (DCO) requirements

---

How to Review / Preview

Switch to branch

git checkout docs/translate-plugin-dev-book-to-en

---

Inspect translated documentation

docs/content/en/docs-dev/plugin-development/

---

Run local Hugo server

cd docs
npm install
npm run start

This verifies:

• Sidebar ordering
• Hugo section rendering
• Navigation structure
• Documentation page hierarchy

within the developer guide.

[rahulshendre]

@vanshika2720, the plugin development book/documentation planned under the LFX mentorship scope.
Please avoid opening PRs in this area for now, and feel free to pick up other good first issues.

Closing for now.

[vanshika2720]

@rahulshendre Apologies. I was already aware this area is planned under the mentorship scope. I opened this PR only as a small proof of concept while exploring the “Plugin Development Book, Docs DX, and Adoption Growth” project idea and understanding the documentation workflow better nothing beyond that. I’ll avoid opening PRs in this area going forward and will focus on other good first issues instead