Just a few basic things to check list when building a integration:
- Generic purpose of integration
- Is all the required source data even available
- Cost benefit analysis
- Test cases
- Transfer Triggers / Interval / Schedule
- Data sources
- Data mapping (Avoid if possible)
- Transfer format
- Data validation
- Transport method
- Data Security / Authentication / Signing / Encryption
- Timeouts / Retransmissions / Other exceptions
- Logging & Reporting
- Monitoring & Alerts
- Key responsible contacts
That's just what I do, every time when I need to build one.
If the data mapping gets very complex. It's highly likely that nobody in the client organization is able to maintain it in future. If it requires stretching to get it right during the development. It's almost guaranteed that it'll fail in future. They'll be blaming the integration.
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