dumping all of the database and utilites into the project, will work on the managers next

common/engine/fdelta.go

@@ -0,0 +1,94 @@
+package engine
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"io/ioutil"
+
+	"github.com/amlwwalker/fdelta"
+)
+
+// var originalFile string
+// var newFile string
+// var patchFile string
+// var appliedFile string
+
+func openReader(file io.Reader) ([]byte, error) {
+	buffer, err := ioutil.ReadAll(file)
+	return buffer, err
+}
+func openFile(path string) ([]byte, error) {
+	data, err := ioutil.ReadFile(path)
+	if err != nil {
+		fmt.Println("File reading error", err)
+	}
+	return data, err
+}
+
+func writeFile(path string, data []byte) error {
+	err := ioutil.WriteFile(path, data, 0644)
+	return err
+}
+
+func getOriginalBytes(originalFile string) ([]byte, error) {
+	originalBytes, err := openFile(originalFile)
+	if err != nil {
+		return []byte{}, err
+	}
+	return originalBytes, nil
+}
+func createDelta(newFile string, originalBytes []byte) ([]byte, error) {
+	newBytes, err := openFile(newFile)
+	if err != nil {
+		return []byte{}, err
+	}
+	delta := fdelta.Create(originalBytes, newBytes)
+	fmt.Println("size of delta ", len(delta))
+	return delta, nil
+}
+func compressDelta(delta []byte) ([]byte, error) {
+	if binaryToGobBuffer, err := compressor.BytesToGob(delta); err != nil {
+		return []byte{}, err
+	} else if compressedData, err := compressor.CompressBinary(&binaryToGobBuffer); err != nil {
+		return []byte{}, err
+	} else {
+		return compressedData.Bytes(), nil
+	}
+}
+func storeDelta(patchFile string, delta []byte) ([]byte, error) {
+	if compressedData, err := compressDelta(delta); err != nil {
+		return []byte{}, err
+	} else if err := writeFile(patchFile, compressedData); err != nil {
+		return []byte{}, err
+	} else {
+		return compressedData, nil
+	}
+}
+func retrieveDelta(patchFile string) ([]byte, error) {
+	compressedData, err := openFile(patchFile)
+	if err != nil {
+		return []byte{}, err
+	}
+	return compressedData, nil
+}
+
+func decompressDelta(compressedData []byte) ([]byte, error) {
+	var compressedBuffer bytes.Buffer
+	compressedBuffer.Write(compressedData)
+	if decompressionReader, err := compressor.DecompressBinary(compressedBuffer); err != nil {
+		return []byte{}, err
+	} else if res, err := compressor.GobToBytes(decompressionReader); err != nil {
+		return []byte{}, err
+	} else {
+		return res, nil
+	}
+}
+
+func applyPatchToFile(originalbytes, delta []byte) ([]byte, error) {
+	if patchedBytes, err := fdelta.Apply(originalbytes, delta); err != nil {
+		return []byte{}, err
+	} else {
+		return patchedBytes, nil
+	}
+}