99 lines
1.9 KiB
Go
99 lines
1.9 KiB
Go
package context
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import (
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"context"
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"errors"
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"log"
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"net/http"
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"net/http/httptest"
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"testing"
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"time"
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)
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type SpyStore struct {
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response string
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t *testing.T
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}
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func (s *SpyStore) Fetch(ctx context.Context) (string, error) {
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data := make(chan string, 1)
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go func() {
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var result string
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for _, c := range s.response {
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select {
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case <-ctx.Done():
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log.Println("spy store got cancelled")
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return
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default:
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time.Sleep(10 * time.Millisecond)
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result += string(c)
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}
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}
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data <- result
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}()
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select {
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case <-ctx.Done():
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return "", ctx.Err()
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case res := <-data:
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return res, nil
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}
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}
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type SpyResponseWriter struct {
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written bool
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}
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func (s *SpyResponseWriter) Header() http.Header {
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s.written = true
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return nil
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}
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func (s *SpyResponseWriter) Write([]byte) (int, error) {
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s.written = true
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return 0, errors.New("not implemented")
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}
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func (s *SpyResponseWriter) WriteHeader(statusCode int) {
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s.written = true
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}
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func TestServer(t *testing.T) {
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t.Run("basic get store", func(t *testing.T) {
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data := "hello, world"
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store := &SpyStore{response: data, t: t}
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srv := Server(store)
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request := httptest.NewRequest(http.MethodGet, "/", nil)
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response := httptest.NewRecorder()
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srv.ServeHTTP(response, request)
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if response.Body.String() != data {
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t.Errorf(`got "%s", want "%s"`, response.Body.String(), data)
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}
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})
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t.Run("tells store to cancel work if request is cancelled", func(t *testing.T) {
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data := "hello, world"
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store := &SpyStore{response: data, t: t}
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srv := Server(store)
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request := httptest.NewRequest(http.MethodGet, "/", nil)
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cancellingCtx, cancel := context.WithCancel(request.Context())
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// Wait 5ms to call cancel
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time.AfterFunc(5*time.Millisecond, cancel)
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request = request.WithContext(cancellingCtx)
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response := &SpyResponseWriter{}
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srv.ServeHTTP(response, request)
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if response.written {
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t.Error("a response should not have been written")
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}
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})
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}
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