999 B
999 B
Indications that you need to sub-divide a service into components:
- Quality of service requirements
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- are there large variations in response times
- ...in transaction processing times
- The business might treat categories of customer differently
- We should actually sub-divide our sales service into RegularCustomers component and StrategicCustomers component
- These things can start to show up when the business starts asking you to treat something (like a customer) in little different ways throughout the system. You end up with a bunch of if statements asking the same question.
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- Ask the business if this is really a new business component
- Fork the code base and let them grow apart. This is liberating as you don't have to maintain both component requirements in one code base.
- More examples
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- Airlines - business vs economy class
- Shipping - frozen goods vs regular toilet paper
- Billing - charging credit cards vs invoicing