63 lines
1.3 KiB
Go
63 lines
1.3 KiB
Go
package glacier_test
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import (
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"bytes"
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"crypto/sha256"
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"fmt"
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"io"
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"github.com/aws/aws-sdk-go/service/glacier"
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)
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func ExampleComputeHashes() {
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r := testCreateReader()
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h := glacier.ComputeHashes(r)
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n, _ := r.Seek(0, 1) // Check position after checksumming
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fmt.Printf("linear: %x\n", h.LinearHash)
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fmt.Printf("tree: %x\n", h.TreeHash)
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fmt.Printf("pos: %d\n", n)
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// Output:
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// linear: 68aff0c5a91aa0491752bfb96e3fef33eb74953804f6a2f7b708d5bcefa8ff6b
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// tree: 154e26c78fd74d0c2c9b3cc4644191619dc4f2cd539ae2a74d5fd07957a3ee6a
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// pos: 0
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}
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func testCreateReader() io.ReadSeeker {
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buf := make([]byte, 5767168) // 5.5MB buffer
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for i := range buf {
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buf[i] = '0' // Fill with zero characters
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}
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return bytes.NewReader(buf)
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}
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func ExampleComputeTreeHash() {
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r := testCreateReader()
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const chunkSize = 1024 * 1024 // 1MB
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buf := make([]byte, chunkSize)
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hashes := [][]byte{}
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for {
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// Reach 1MB chunks from reader to generate hashes from
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n, err := io.ReadAtLeast(r, buf, chunkSize)
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if n == 0 {
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break
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}
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tmpHash := sha256.Sum256(buf[:n])
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hashes = append(hashes, tmpHash[:])
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if err != nil {
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break // last chunk
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}
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}
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treeHash := glacier.ComputeTreeHash(hashes)
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fmt.Printf("TreeHash: %x\n", treeHash)
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// Output:
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// TreeHash: 154e26c78fd74d0c2c9b3cc4644191619dc4f2cd539ae2a74d5fd07957a3ee6a
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}
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