76 lines
1.7 KiB
Go
76 lines
1.7 KiB
Go
package circuitbreaker_test
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import (
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"context"
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"errors"
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"fmt"
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"path/filepath"
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"runtime"
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"testing"
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"time"
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"github.com/go-kit/kit/endpoint"
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)
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func testFailingEndpoint(
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t *testing.T,
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breaker endpoint.Middleware,
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primeWith int,
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shouldPass func(int) bool,
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requestDelay time.Duration,
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openCircuitError string,
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) {
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_, file, line, _ := runtime.Caller(1)
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caller := fmt.Sprintf("%s:%d", filepath.Base(file), line)
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// Create a mock endpoint and wrap it with the breaker.
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m := mock{}
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var e endpoint.Endpoint
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e = m.endpoint
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e = breaker(e)
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// Prime the endpoint with successful requests.
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for i := 0; i < primeWith; i++ {
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if _, err := e(context.Background(), struct{}{}); err != nil {
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t.Fatalf("%s: during priming, got error: %v", caller, err)
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}
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time.Sleep(requestDelay)
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}
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// Switch the endpoint to start throwing errors.
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m.err = errors.New("tragedy+disaster")
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m.through = 0
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// The first several should be allowed through and yield our error.
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for i := 0; shouldPass(i); i++ {
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if _, err := e(context.Background(), struct{}{}); err != m.err {
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t.Fatalf("%s: want %v, have %v", caller, m.err, err)
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}
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time.Sleep(requestDelay)
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}
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through := m.through
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// But the rest should be blocked by an open circuit.
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for i := 0; i < 10; i++ {
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if _, err := e(context.Background(), struct{}{}); err.Error() != openCircuitError {
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t.Fatalf("%s: want %q, have %q", caller, openCircuitError, err.Error())
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}
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time.Sleep(requestDelay)
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}
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// Make sure none of those got through.
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if want, have := through, m.through; want != have {
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t.Errorf("%s: want %d, have %d", caller, want, have)
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}
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}
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type mock struct {
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through int
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err error
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}
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func (m *mock) endpoint(context.Context, interface{}) (interface{}, error) {
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m.through++
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return struct{}{}, m.err
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}
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