aws.go

//
// goamz - Go packages to interact with the Amazon Web Services.
//
//   https://wiki.ubuntu.com/goamz
//
// Copyright (c) 2011 Canonical Ltd.
//
// Written by Gustavo Niemeyer <gustavo.niemeyer@canonical.com>
//
package aws

import (
	"errors"
	"os"
)

// Region defines the URLs where AWS services may be accessed.
//
// See http://goo.gl/d8BP1 for more details.
type Region struct {
	EC2Endpoint string
	S3Endpoint  string
	SDBEndpoint string
	SNSEndpoint string
	SQSEndpoint string
}

var USEast = Region{
	"https://ec2.us-east-1.amazonaws.com",
	"https://s3.amazonaws.com",
	"https://sdb.amazonaws.com",
	"https://sns.us-east-1.amazonaws.com",
	"https://sqs.us-east-1.amazonaws.com",
}

var USWest = Region{
	"https://ec2.us-west-1.amazonaws.com",
	"https://s3-us-west-1.amazonaws.com",
	"https://sdb.us-west-1.amazonaws.com",
	"https://sns.us-west-1.amazonaws.com",
	"https://sqs.us-west-1.amazonaws.com",
}

var EUWest = Region{
	"https://ec2.eu-west-1.amazonaws.com",
	"https://s3-eu-west-1.amazonaws.com",
	"https://sdb.eu-west-1.amazonaws.com",
	"https://sns.eu-west-1.amazonaws.com",
	"https://sqs.eu-west-1.amazonaws.com",
}

var APSoutheast = Region{
	"https://ec2.ap-southeast-1.amazonaws.com",
	"https://s3-ap-southeast-1.amazonaws.com",
	"https://sdb.ap-southeast-1.amazonaws.com",
	"https://sns.ap-southeast-1.amazonaws.com",
	"https://sqs.ap-southeast-1.amazonaws.com",
}

var APNortheast = Region{
	"https://ec2.ap-northeast-1.amazonaws.com",
	"https://s3-ap-northeast-1.amazonaws.com",
	"https://sdb.ap-northeast-1.amazonaws.com",
	"https://sns.ap-northeast-1.amazonaws.com",
	"https://sqs.ap-northeast-1.amazonaws.com",
}

type Auth struct {
	AccessKey, SecretKey string
}

var unreserved = make([]bool, 128)
var hex = "0123456789ABCDEF"

func init() {
	// RFC3986
	u := "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz01234567890-_.~"
	for _, c := range u {
		unreserved[c] = true
	}
}

// EnvAuth creates an Auth based on environment information.
// The AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY environment
// variables are used.
func EnvAuth() (auth Auth, err error) {
	auth.AccessKey = os.Getenv("AWS_ACCESS_KEY_ID")
	auth.SecretKey = os.Getenv("AWS_SECRET_ACCESS_KEY")
	if auth.AccessKey == "" {
		err = errors.New("AWS_ACCESS_KEY_ID not found in environment")
	}
	if auth.SecretKey == "" {
		err = errors.New("AWS_SECRET_ACCESS_KEY not found in environment")
	}
	return
}

// Encode takes a string and URI-encodes it in a way suitable
// to be used in AWS signatures.
func Encode(s string) string {
	encode := false
	for i := 0; i != len(s); i++ {
		c := s[i]
		if c > 127 || !unreserved[c] {
			encode = true
			break
		}
	}
	if !encode {
		return s
	}
	e := make([]byte, len(s)*3)
	ei := 0
	for i := 0; i != len(s); i++ {
		c := s[i]
		if c > 127 || !unreserved[c] {
			e[ei] = '%'
			e[ei+1] = hex[c>>4]
			e[ei+2] = hex[c&0xF]
			ei += 3
		} else {
			e[ei] = c
			ei += 1
		}
	}
	return string(e[:ei])
}