Golang : Compress and decompress file with compress/flate example
A quick and simple tutorial on how to compress a file with Golang's compress/flate
package. Package flate implements the DEFLATE compressed data format, as described in RFC 1951.
To compress a file, pipe and flush the data out with NewWriter()
function :
package main
import (
"compress/flate"
"fmt"
"io"
"os"
)
func main() {
inputFile, err := os.Open("file.txt")
if err != nil {
fmt.Println(err)
os.Exit(1)
}
defer inputFile.Close()
outputFile, err := os.Create("file.txt.compressed")
if err != nil {
fmt.Println(err)
os.Exit(1)
}
defer outputFile.Close()
flateWriter, err := flate.NewWriter(outputFile, flate.BestCompression)
if err != nil {
fmt.Println("NewWriter error ", err)
os.Exit(1)
}
defer flateWriter.Close()
io.Copy(flateWriter, inputFile)
flateWriter.Flush()
}
Sample test data :
>cat file.txt
This is a test file for Golang Compress/Flate
This is a test file for Golang Compress/Flate
This is a test file for Golang Compress/Flate
This is a test file for Golang Compress/Flate
This is a test file for Golang Compress/Flate
This is a test file for Golang Compress/Flate
>cat file.txt.compressed
��,V�D������T���"��ļt��܂���b}��ĒT�Q�#U5����
To decompress the file, read in the compressed data with NewReader()
function before piping out the decompressed data to file
package main
import (
"compress/flate"
"fmt"
"io"
"os"
)
func main() {
inputFile, err := os.Open("file.txt.compressed")
if err != nil {
fmt.Println(err)
os.Exit(1)
}
defer inputFile.Close()
outputFile, err := os.Create("file.txt.decompressed")
if err != nil {
fmt.Println(err)
os.Exit(1)
}
defer outputFile.Close()
flateReader := flate.NewReader(inputFile)
defer flateReader.Close()
io.Copy(outputFile, flateReader)
}
Happy coding!
Reference :
See also : Golang : Gzip file example
By Adam Ng
IF you gain some knowledge or the information here solved your programming problem. Please consider donating to the less fortunate or some charities that you like. Apart from donation, planting trees, volunteering or reducing your carbon footprint will be great too.
Advertisement
Tutorials
+28.1k Golang : Decode/unmarshal unknown JSON data type with map[string]interface
+14.3k Javascript : Prompt confirmation before exit
+10.7k RPM : error: db3 error(-30974) from dbenv->failchk: DB_RUNRECOVERY: Fatal error, run database recovery
+8.3k Golang : Reverse text lines or flip line order example
+19.4k Golang : Check if directory exist and create if does not exist
+31.7k Golang : Example for ECDSA(Elliptic Curve Digital Signature Algorithm) package functions
+12.5k Golang : Search and extract certain XML data example
+14.3k Golang : syscall.Socket example
+5.6k Golang : If else example and common mistake
+14.6k Golang : Rename directory
+9.5k Golang : Timeout example
+9.6k Mac OSX : Get a process/daemon status information