a323d2fd51
This is the core part of KCL by implementing worker. It has exactly the same interface as Amazon's KCL. Internally, it uses code from GoKini in order to get the library functionaly quickly. This is a working version. The test code worker_test.go shows how to use this library. Dynamic resharding feature is out of the scope of M4. Test: 1. A Kinesis stream named "kcl-test" has been created under photon-infra account. 2. Download your AWS Credential from IAM user page. 3. Modify the worker_test.go to fill in your aws credential. 4. hmake test Jira CNA-637 Change-Id: I886d255bab9adaf7a13bca11bfda51bedaacaaed
30 lines
806 B
Go
30 lines
806 B
Go
package utils
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import (
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"math/rand"
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)
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const letterBytes = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
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const (
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letterIdxBits = 6 // 6 bits to represent a letter index
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letterIdxMask = 1<<letterIdxBits - 1 // All 1-bits, as many as letterIdxBits
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letterIdxMax = 63 / letterIdxBits // # of letter indices fitting in 63 bits
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)
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func RandStringBytesMaskImpr(n int) string {
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b := make([]byte, n)
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// A rand.Int63() generates 63 random bits, enough for letterIdxMax letters!
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for i, cache, remain := n-1, rand.Int63(), letterIdxMax; i >= 0; {
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if remain == 0 {
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cache, remain = rand.Int63(), letterIdxMax
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}
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if idx := int(cache & letterIdxMask); idx < len(letterBytes) {
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b[i] = letterBytes[idx]
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i--
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}
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cache >>= letterIdxBits
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remain--
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}
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return string(b)
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}
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