软件架构难点解惑（Software Architecture: The Hard Parts 影印版）

在软件架构中没有哪个决定是轻而易举的。相反，有许多艰难的部分，要么是难题，要么是缺少最佳实践，这迫使你在各种妥协中做出选择。通过本书，你将学会如何批判性地思考分布式架构的利弊。
软件架构老兵和实践顾问Neal Ford、Mark Richards、Pramod Sadalage、zhamak Dehghani讨论了选择适合架构的策略。全书交织着一群虚构的技术专业人员(Sysops Squad)的故事，他们研究了从如何确定服务粒度、管理工作流和编排、管理和解耦契约、管理分布式事务到如何优化可扩展性、弹性和性能等操作特性的一切问题。
本书通过关注常见的问题，提供了一些技巧，帮助你在面对架构问题时进行权衡。
·分析权衡并有效记录你的决策
·作出更好的服务粒度决策
·理解拆分单体应用的复杂性
·管理和解耦服务之间的契约
·在高度分布式架构中处理数据
·学习在分解应用时的工作流和事务管理模式

尼尔·福特（Neal Ford）是ThoughtWorks软件架构师、Meme Wrangler，曾任DSW集团CTO，是国际公认的软件开发与交付专家。

Preface
1. What Happens When There Are No"Best Practices"?
Why "The Hard Parts"?
Giving Timeless Advice About Software Architecture
The Importance of Data in Architecture
Architectural Decision Records
Architecture Fitness Functions
Using Fitness Functions
Architecture Versus Design: Keeping Definitions Simple
Introducing the Sysops Squad Saga
Nonticketing Work_flow
Ticketing Workflow
A Bad Scenario
Sysops Squad Architectural Components
Sysops Squad Data Model
Part I. Pulling Things Apart
2. Discerning Coupling in Software Architecture
Architecture (Quantum [ Quanta)
Independently Deployable
High Functional Cohesion
High Static Coupling
Dynamic Quantum Coupling
Sysops Squad Saga: Understanding Quanta
3. Architectural Modularity
Modularity Drivers
Maintainability
Testability
Deployability
Scalability
Availability/Fault Tolerance
Sysops Squad Saga: Creating a Business Case
4. Architectural Decomposition
Is the Codebase Decomposable?
Afferent and Efferent Coupling
Abstractness and Instability
Distance from the Main Sequence
Component-Based Decomposition
Tactical Forking
Trade-Offs
Sysops Squad Saga: Choosing a Decomposition Approach
5. Component-Based Decomposition Patterns
Identify and Size Components Pattern
Pattern Description
Fitness Functions for Governance
Sysops Squad Saga: Sizing Components
Gather Common Domain Components Pattern
Pattern Description
Fitness Functions for Governance
Sysops Squad Saga: Gathering Common Components
Flatten Components Pattern
Pattern' Description
Fitness Functions for Governance
Sysops Squad Saga: Flattening Components
Determine Component Dependencies Pattern
Pattern Description
Fitness Functions for Governance
Sysops Squad Saga: Identifying Component Dependencies
Create Component Domains Pattern
Pattern Description
Fitness Functions for Governance
Sysops Squad Saga: Creating Component Domains
Create Domain Services Pattern
Pattern Description
Fitness Functions for Governance
Sysops Squad Saga: Creating Domain Services
Summary
6. Pulling Apart Operational Data
Data Decomposition Drivers
Data Disintegrators
Data Integrators
Sysops Squad Saga: Justifying Database Decomposition
Decomposing Monolithic Data
Step 1: Analyze Database and Create Data Domains
Step 2: Assign Tables to Data Domains
Step 3: Separate Database Connections to Data Domains
Step 4: Move Schemas to Separate Database Servers
Step 5: Switch Over to Independent Database Servers
Selecting a Database Type
Relational Databases
Key-Value Databases
Document Databases
Column Family Databases
Graph Databases
NewSQL Databases
Cloud Native Databases
Time-Series Databases
Sysops Squad Saga: Polyglot Databases
7. Service Granularity
Granularity Disintegrators
Service Scope and Function
Code Volatility
Scalability and Throughput
Fault Tolerance
Security
Extensibility
Granularity Integrators
Database Transactions
Workflow and Choreography
Shared Code
Data Relationships
Finding the Right Balance
Sysops Squad Saga: Ticket Assignment Granularity
Sysops Squad Saga: Customer Registration Granularity
Part II. Putting Things Back Together
8. Reuse Patterns
Code Replication
When to Use
Shared Library
Dependency Management and Change Control
Versioning Strategies
When To Use
Shared Service
Change Risk
Performance
Scalability
Fault Tolerance
When to Use
Sidecars and Servic