Flute - Golang HTTP Client testing framework

I introduce my OSS `flute`, which is the HTTP client testing framework for Golang.
https://github.com/suzuki-shunsuke/flute

1. Flute ‒ Go HTTP Client Testing Framework 2019-07-13 Shunsuke Suzuki 1
2. Who am I? https://github.com/suzuki-shunsuke/profile Backend and DevOps engineer in Japan I love Golang 2
3. Overview • Introduction of my OSS `flute`, which is the HTTP client testing framework for Golang • How to test HTTP request parameters and mock the API server 3
4. Do you write API clients of Go? 4
5. Do you write tests of API clients of Go? 5
6. Tests of the API client Request parameters • HTTP method, request path, query, header, request body, etc Response • parse of response body 6
7. Tests of the API client Request parameters • HTTP method, request path, query, header, request body, etc Response • parse of response body They are common to all API clients, so letʼs do them at the framework 7
8. Other libraries in awesome-go There are many libraries for testing of HTTP clients. • https://github.com/avelino/awesome-go#testing • https://github.com/h2non/gock • https://github.com/seborama/govcr • https://github.com/jarcoal/httpmock • https://github.com/tv42/mockhttp • https://github.com/gavv/httpexpect • https://github.com/dnaeon/go-vcr • https://github.com/h2non/baloo • etc 8
9. So why do I develop flute? • We can mock the HTTP server with them, but we canʼt test the request parameters with them • I used gock, but it is inconvenient that we canʼt understand why the request matches no mock 9
10. So why do I develop flute? • We can mock the HTTP server with them, but we canʼt test the request parameters with them • I used gock, but it is inconvenient that we canʼt understand why the request matches no mock I canʼt find the library meets my needs completely, so I decided to develop it by myself 10
11. How to write the mock server in Go • run the mock server with httptest • customize http.Clientʼs Transport 11
12. How to write the mock server in Go • run the mock server with httptest • customize http.Clientʼs Transport <- flute choices this 12
13. Flute ‒ HTTP client testing framework • https://github.com/suzuki-shunsuke/flute • HTTP client testing framework for Golang 13
14. Features • tests of request parameters • HTTP method, request path, query, header, request body, etc • mock the HTTP server 14
15. Example: API client to create a user 15
16. 16 https://github.com/suzuki-shunsuke/flute/blob/master/examples/create_user.go
17. pass *flute.Transport to http.Client.Transport 17 https://github.com/suzuki-shunsuke/flute/blob/master/examples/create_user_test.go
19. 19 1. match the request with Matcher 2. test the request with Tester 3. returns the response with Response
20. 20 we can define the test case declaratively
21. assertion of the request parameters flute uses testify internally, so it is easy to understand why the test fails 21
22. 22 ex. in case the request headers arenʼt expected
23. Conclusion • I develop the OSS `flute`, which is the HTTP client testing framework for Golang • With flute we can not only mock the API server but also test the request parameters • With flute we can define the tests declaratively • In Go, we can mock the HTTP server easily with http.RoundTripper 23