Go by Example

Embed Directive

Use //go:embed to bundle a file into a string, byte slice, or embed.FS at build time.

The //go:embed directive copies files into a binary at build time. Put the directive immediately before a string, byte slice, or embed.FS variable.

This example expects greeting.txt beside the Go source file. The embedded string is available when the program runs, without opening a separate disk file.

package main
 
import (
    _ "embed"
    "fmt"
)
 
//go:embed greeting.txt
var greeting string
 
func main() {
    fmt.Print(greeting)
}

In production

Embedded data is read-only and increases the binary size. embed.FS implements fs.FS, so it works with APIs such as template.ParseFS that accept that interface. Embed only files that belong in the deployed binary.

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