package rest
import (
"bytes"
"encoding/base64"
"encoding/json"
"fmt"
"io"
"io/ioutil"
"net/http"
"reflect"
"strconv"
"strings"
"time"
"github.com/aws/aws-sdk-go/aws"
"github.com/aws/aws-sdk-go/aws/awserr"
"github.com/aws/aws-sdk-go/aws/request"
)
// UnmarshalHandler is a named request handler for unmarshaling rest protocol requests
var UnmarshalHandler = request.NamedHandler{Name: "awssdk.rest.Unmarshal", Fn: Unmarshal}
// UnmarshalMetaHandler is a named request handler for unmarshaling rest protocol request metadata
var UnmarshalMetaHandler = request.NamedHandler{Name: "awssdk.rest.UnmarshalMeta", Fn: UnmarshalMeta}
// Unmarshal unmarshals the REST component of a response in a REST service.
func Unmarshal(r *request.Request) {
if r.DataFilled() {
v := reflect.Indirect(reflect.ValueOf(r.Data))
unmarshalBody(r, v)
}
}
// UnmarshalMeta unmarshals the REST metadata of a response in a REST service
func UnmarshalMeta(r *request.Request) {
r.RequestID = r.HTTPResponse.Header.Get("X-Amzn-Requestid")
if r.RequestID == "" {
// Alternative version of request id in the header
r.RequestID = r.HTTPResponse.Header.Get("X-Amz-Request-Id")
}
if r.DataFilled() {
v := reflect.Indirect(reflect.ValueOf(r.Data))
unmarshalLocationElements(r, v)
}
}
func unmarshalBody(r *request.Request, v reflect.Value) {
if field, ok := v.Type().FieldByName("_"); ok {
if payloadName := field.Tag.Get("payload"); payloadName != "" {
pfield, _ := v.Type().FieldByName(payloadName)
if ptag := pfield.Tag.Get("type"); ptag != "" && ptag != "structure" {
payload := v.FieldByName(payloadName)
if payload.IsValid() {
switch payload.Interface().(type) {
case []byte:
defer r.HTTPResponse.Body.Close()
b, err := ioutil.ReadAll(r.HTTPResponse.Body)
if err != nil {
r.Error = awserr.New("SerializationError", "failed to decode REST response", err)
} else {
payload.Set(reflect.ValueOf(b))
}
case *string:
defer r.HTTPResponse.Body.Close()
b, err := ioutil.ReadAll(r.HTTPResponse.Body)
if err != nil {
r.Error = awserr.New("SerializationError", "failed to decode REST response", err)
} else {
str := string(b)
payload.Set(reflect.ValueOf(&str))
}
default:
switch payload.Type().String() {
case "io.ReadCloser":
payload.Set(reflect.ValueOf(r.HTTPResponse.Body))
case "io.ReadSeeker":
b, err := ioutil.ReadAll(r.HTTPResponse.Body)
if err != nil {
r.Error = awserr.New("SerializationError",
"failed to read response body", err)
return
}
payload.Set(reflect.ValueOf(ioutil.NopCloser(bytes.NewReader(b))))
default:
io.Copy(ioutil.Discard, r.HTTPResponse.Body)
defer r.HTTPResponse.Body.Close()
r.Error = awserr.New("SerializationError",
"failed to decode REST response",
fmt.Errorf("unknown payload type %s", payload.Type()))
}
}
}
}
}
}
}
func unmarshalLocationElements(r *request.Request, v reflect.Value) {
for i := 0; i < v.NumField(); i++ {
m, field := v.Field(i), v.Type().Field(i)
if n := field.Name; n[0:1] == strings.ToLower(n[0:1]) {
continue
}
if m.IsValid() {
name := field.Tag.Get("locationName")
if name == "" {
name = field.Name
}
switch field.Tag.Get("location") {
case "statusCode":
unmarshalStatusCode(m, r.HTTPResponse.StatusCode)
case "header":
err := unmarshalHeader(m, r.HTTPResponse.Header.Get(name), field.Tag)
if err != nil {
r.Error = awserr.New("SerializationError", "failed to decode REST response", err)
break
}
case "headers":
prefix := field.Tag.Get("locationName")
err := unmarshalHeaderMap(m, r.HTTPResponse.Header, prefix)
if err != nil {
r.Error = awserr.New("SerializationError", "failed to decode REST response", err)
break
}
}
}
if r.Error != nil {
return
}
}
}
func unmarshalStatusCode(v reflect.Value, statusCode int) {
if !v.IsValid() {
return
}
switch v.Interface().(type) {
case *int64:
s := int64(statusCode)
v.Set(reflect.ValueOf(&s))
}
}
func unmarshalHeaderMap(r reflect.Value, headers http.Header, prefix string) error {
switch r.Interface().(type) {
case map[string]*string: // we only support string map value types
out := map[string]*string{}
for k, v := range headers {
k = http.CanonicalHeaderKey(k)
if strings.HasPrefix(strings.ToLower(k), strings.ToLower(prefix)) {
out[k[len(prefix):]] = &v[0]
}
}
r.Set(reflect.ValueOf(out))
}
return nil
}
func unmarshalHeader(v reflect.Value, header string, tag reflect.StructTag) error {
isJSONValue := tag.Get("type") == "jsonvalue"
if isJSONValue {
if len(header) == 0 {
return nil
}
} else if !v.IsValid() || (header == "" && v.Elem().Kind() != reflect.String) {
return nil
}
switch v.Interface().(type) {
case *string:
v.Set(reflect.ValueOf(&header))
case []byte:
b, err := base64.StdEncoding.DecodeString(header)
if err != nil {
return err
}
v.Set(reflect.ValueOf(&b))
case *bool:
b, err := strconv.ParseBool(header)
if err != nil {
return err
}
v.Set(reflect.ValueOf(&b))
case *int64:
i, err := strconv.ParseInt(header, 10, 64)
if err != nil {
return err
}
v.Set(reflect.ValueOf(&i))
case *float64:
f, err := strconv.ParseFloat(header, 64)
if err != nil {
return err
}
v.Set(reflect.ValueOf(&f))
case *time.Time:
t, err := time.Parse(RFC822, header)
if err != nil {
return err
}
v.Set(reflect.ValueOf(&t))
case aws.JSONValue:
b := []byte(header)
var err error
if tag.Get("location") == "header" {
b, err = base64.StdEncoding.DecodeString(header)
if err != nil {
return err
}
}
m := aws.JSONValue{}
err = json.Unmarshal(b, &m)
if err != nil {
return err
}
v.Set(reflect.ValueOf(m))
default:
err := fmt.Errorf("Unsupported value for param %v (%s)", v.Interface(), v.Type())
return err
}
return nil
}