Agile software development with its short life cycles and frequent updates poses high risks with respect to breaking existing functionalities and, as a consequence, may compromise the correctness of an application. We discuss the issues and challenges that arise in the context of the data-intensive business applications developed by abuscom and show how certain risks can be mitigated by our approach to API level regression testing.

1. API Level Regression
Testing: a Field Report
Leonhard Holzer & Kurt Ranalter
SFScon 2018

2. Mission statement
• Software company from Bruneck-Brunico
• BI, quality control & production planning tools
• Customers: automotive industry, local business
• Agile, CI/CD: continuous integration & delivery
• One of our aims is to deliver high quality SW
• Testing is crucial to avoid breaking functionality
• But testing is not for free, it costs time and effort
• Apit: our API level regression testing framework
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3. Example application
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4. Issues & challenges
• Page dependencies
• PNL & balance → cash flow
• Accruals → PNL & balance
• Input dependencies
• Drilldowns & data aggregation
• Aggregated row ↔ data row
(→) depending on reference column
• TY column ↔ month column
(→) based on month, working days
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5. Behind the scenes
Post request Get request
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6. Architecture & testing
• Focus on testing business logic
• End-to-end testing not really an option
• Usual solution: unit & integration tests
• Requires extensive setup and mocking
• Why not make use of REST API?
• Simulate usage as in end-to-end testing
• Business logic considered as black box
• Not a substitute but complementary
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7. Apit DSL for requests
Post request Apit test case
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8. How does it work?
• In a nutshell
1. Add framework as library
2. Read and parse config files
3. Run as JUnit5 dynamic tests
• Build pipeline
1. DB/auth as docker container
2. Tests just run as maven goals
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9. Concluding remarks
• Design decisions & supported features
• Exploit framework to generate necessary test data
• Actual/expected as JSON (WIP: git to track changes)
• Payloads from file instead of coding it into config
• Parameters for testing in multiple environments
• Quick & easy to use but still powerful
• No need for mocking, relatively simple to maintain
• Good integration with respect to our build pipeline
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10. That‘s it, thanks!
www.abuscom.com
info@abuscom.com
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