The official AWS process for exporting a DynamoDB table is overly complex. These two scripts make exporting and importing much easier.

export.go

package main

import (
  "bytes"
	"flag"
	"fmt"
	"github.com/bmizerany/aws4"
	"io/ioutil"
	"log"
	"net/http"
	"time"
)

var (
	t = flag.String("t", "", "Table Name")
	k = flag.String("k", "", "AWS Key")
	s = flag.String("s", "", "AWS Secret")

	keys *aws4.Keys
	svc  *aws4.Service
)

// Usage: go run export.go -k [AWS-KEY] -s [AWS-SECRET] -t [TABLE-NAME] > table.json
//
// Exports a DynamoDB table into a JSON file

func init() {
	flag.Parse()
	keys = &aws4.Keys{
		AccessKey: *k,
		SecretKey: *s,
	}

	svc = &aws4.Service{
		Name:   "dynamodb",
		Region: "us-east-1",
	}
}

func main() {
	q := fmt.Sprintf(`{ "TableName": %q }`, *t)
	buf := bytes.NewReader([]byte(q))
	url := "https://dynamodb.us-east-1.amazonaws.com/"
	req, _ := http.NewRequest("POST", url, buf)

	req.Header.Set("Date", time.Now().UTC().Format(http.TimeFormat))
	req.Header.Set("X-Amz-Target", "DynamoDB_20111205.Scan")
	req.Header.Set("Content-Type", "application/x-amz-json-1.0")

	err := svc.Sign(keys, req)
	if err != nil {
		log.Fatalf("fn=Sign error=%q", err)
	}

	res, err := http.DefaultClient.Do(req)
	if err != nil {
		log.Fatalf("fn=Do error=%q", err)
	}

	defer res.Body.Close()
	payload, err := ioutil.ReadAll(res.Body)
	if err != nil {
		log.Fatalf("fn=ReadAll error=%q", err)
	}

	fmt.Printf("%s", payload)
}

import.go

package main

import (
  "bytes"
	"encoding/json"
	"flag"
	"github.com/bmizerany/aws4"
	"io/ioutil"
	"log"
	"net/http"
	"time"
)

var (
	f = flag.String("f", "", "File Path")
	t = flag.String("t", "", "Table Name")
	k = flag.String("k", "", "AWS Key")
	s = flag.String("s", "", "AWS Secret")

	keys *aws4.Keys
	svc  *aws4.Service
)

// Usage: go run import.go -k [AWS-KEY] -s [AWS-SECRET] -t [TABLE-NAME] -f [FILE-NAME]
//
// Imports a JSON file into an existing DynamoDB table

func init() {
	flag.Parse()
	keys = &aws4.Keys{
		AccessKey: *k,
		SecretKey: *s,
	}

	svc = &aws4.Service{
		Name:   "dynamodb",
		Region: "us-east-1",
	}
}

func main() {
	b, err := ioutil.ReadFile(*f)
	if err != nil {
		log.Fatalf("fn=ReadFile error=%q", err)
	}

	var d struct {
		Items []map[string]map[string]string
	}

	err = json.Unmarshal(b, &d)
	if err != nil {
		log.Fatalf("fn=Unmarshal error=%q", err)
	}

	for _, i := range d.Items {
		var q struct {
			TableName string
			Item      map[string]map[string]string
		}

		q.TableName = *t
		q.Item = i

		payload, err := json.Marshal(q)
		if err != nil {
			log.Fatalf("fn=Marshal error=%q", err)
		}

		log.Printf("at=import table=%s bytes=%d", *t, len(payload))

		buf := bytes.NewReader(payload)
		url := "https://dynamodb.us-east-1.amazonaws.com/"
		req, _ := http.NewRequest("POST", url, buf)

		req.Header.Set("Date", time.Now().UTC().Format(http.TimeFormat))
		req.Header.Set("X-Amz-Target", "DynamoDB_20120810.PutItem")
		req.Header.Set("Content-Type", "application/x-amz-json-1.0")

		err = svc.Sign(keys, req)
		if err != nil {
			log.Fatalf("fn=Sign error=%q", err)
		}

		res, err := http.DefaultClient.Do(req)
		if err != nil {
			log.Fatalf("fn=Do error=%q", err)
		}

		if res.StatusCode != 200 {
			msg, _ := ioutil.ReadAll(res.Body)
			log.Printf("at=response error=%q", res.Status, msg)
		}
	}
}