Golang : Convert(cast) bytes.Buffer or bytes.NewBuffer type to io.Reader
Problem :
You need to convert or type cast bytes.Buffer
or bytes.NewBuffer
type to io.Reader
to use in io.MultiReader()
function because of this error :
cannot use buffer_slice (type []*bytes.Buffer) as type io.Reader in argument to io.MultiReader: []*bytes.Buffer does not implement io.Reader (missing Read method).
Solution :
Wrap the bytes.Buffer
with io.Reader array
. For example :
package main
import (
"bytes"
"fmt"
"io"
"io/ioutil"
)
func main() {
readerBuffer := bytes.NewBuffer([]byte("abcdefghijkl"))
readerBuffer2 := bytes.NewBuffer([]byte("mnopqrstuvwxyz"))
buff := []io.Reader{readerBuffer, readerBuffer2} // <------ here
combined := io.MultiReader(buff...)
data, _ := ioutil.ReadAll(combined)
fmt.Println(string(data))
}
or
package main
import (
"bytes"
"fmt"
"io"
"io/ioutil"
)
func main() {
//readerBuffer := bytes.NewBuffer([]byte("abcdefghijkl"))
readerBuffer := &bytes.Buffer{}
readerBuffer.Write([]byte("abcdefghijkl"))
//readerBuffer2 := bytes.NewBuffer([]byte("mnopqrstuvwxyz"))
readerBuffer2 := &bytes.Buffer{}
readerBuffer2.Write([]byte("mnopqrstuvwxyz"))
buff := []io.Reader{readerBuffer, readerBuffer2} // <------ here
combined := io.MultiReader(buff...)
data, _ := ioutil.ReadAll(combined)
fmt.Println(string(data))
}
Reference :
https://socketloop.com/references/golang-io-multireader-function-example
See also : Golang : Convert(cast) []byte to io.Reader type
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
+11.4k Golang : convert(cast) float to string
+13.5k Golang : Reverse IP address for reverse DNS lookup example
+18.8k Golang : Get RGBA values of each image pixel
+5.1k Swift : Convert string array to array example
+8.9k Golang : Generate Codabar
+11.1k Golang : Generate DSA private, public key and PEM files example
+21.2k Golang : Upload big file (larger than 100MB) to AWS S3 with multipart upload
+6.4k Nginx : Password protect a directory/folder
+13.6k Golang : concatenate(combine) strings
+10.5k Golang : How to transmit update file to client by HTTP request example
+19k Golang : Get current URL example
+4.5k Python : Find out the variable type and determine the type with simple test