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This adds a generic way of start a check function to check a backend. This package can be used to kick off healthchecks. The package makes sure only 1 is run at any one time. It should allow for: See upstream error -> kick off healthcheck and not to worry about overwhelming the upstream with a barrage of queries.
41 lines
813 B
Go
41 lines
813 B
Go
package up
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import (
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"sync"
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"sync/atomic"
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"testing"
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"time"
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)
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func TestUp(t *testing.T) {
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pr := New()
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wg := sync.WaitGroup{}
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hits := int32(0)
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upfunc := func(s string) bool {
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atomic.AddInt32(&hits, 1)
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// Sleep tiny amount so that our other pr.Do() calls hit the lock.
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time.Sleep(3 * time.Millisecond)
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wg.Done()
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return true
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}
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pr.Start("nonexistent", 5*time.Millisecond)
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defer pr.Stop()
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// These functions AddInt32 to the same hits variable, but we only want to wait when
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// upfunc finishes, as that only calls Done() on the waitgroup.
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upfuncNoWg := func(s string) bool { atomic.AddInt32(&hits, 1); return true }
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wg.Add(1)
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pr.Do(upfunc)
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pr.Do(upfuncNoWg)
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pr.Do(upfuncNoWg)
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wg.Wait()
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h := atomic.LoadInt32(&hits)
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if h != 1 {
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t.Errorf("Expected hits to be %d, got %d", 1, h)
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}
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}
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