Code:play 

package main

import (
	"context"
	"fmt"
	"log"

	"gocloud.dev/blob"
)

func main() {
	// blob.OpenBucket creates a *blob.Bucket from a URL.
	b, err := blob.OpenBucket(context.Background(), "mem://")
	if err != nil {
		log.Fatal(err)
	}
	defer b.Close()

	// Now we can use b to read or write files to the container.
	ctx := context.Background()
	err = b.WriteAll(ctx, "my-key", []byte("hello world"), nil)
	if err != nil {
		log.Fatal(err)
	}
	data, err := b.ReadAll(ctx, "my-key")
	if err != nil {
		log.Fatal(err)
	}
	fmt.Println(string(data))

}

Output:

hello world

Code:play 

package main

import (
	"context"
	"fmt"
	"log"

	"gocloud.dev/blob/memblob"
)

func main() {
	// PRAGMA: This example is used on gocloud.dev; PRAGMA comments adjust how it is shown and can be ignored.
	// PRAGMA: On gocloud.dev, hide lines until the next blank line.
	ctx := context.Background()

	// Create an in-memory bucket.
	bucket := memblob.OpenBucket(nil)
	defer bucket.Close()

	// Now we can use bucket to read or write files to the bucket.
	err := bucket.WriteAll(ctx, "my-key", []byte("hello world"), nil)
	if err != nil {
		log.Fatal(err)
	}
	data, err := bucket.ReadAll(ctx, "my-key")
	if err != nil {
		log.Fatal(err)
	}
	fmt.Println(string(data))

}

Output:

hello world