Example to create Rackspace Files TempURL with golang

main.go

package main

// Based on documentation found here: http://docs.rackspace.com/files/api/v1/cf-devguide/content/Create_TempURL-d1a444.html

import (
        "crypto/hmac"
        "crypto/sha1"
        "encoding/hex"
        "fmt"
        "github.com/ncw/swift"
        "path"
        "time"
)

func tempUrlSignature(tempKey string, path string, expiration time.Time) string {
        body := fmt.Sprintf("GET\n%d\n%s", expiration.Unix(), path)

        max := hmac.New(sha1.New, []byte(tempKey))
        max.Write([]byte(body))
        sig := hex.EncodeToString(max.Sum(nil))

        return sig
}

func tempUrl(tempKey string, storageUrl string, containerName string, objectName string, expiration time.Time) string {
        _, accountName := path.Split(storageUrl)

        requestPath := fmt.Sprintf("/v1/%s/%s/%s", accountName, containerName, objectName)
        signature := tempUrlSignature(tempKey, requestPath, expiration)
        tempUrl := fmt.Sprintf("%s/%s/%s?temp_url_sig=%s&temp_url_expires=%d", storageUrl, containerName, objectName, signature, expiration.Unix())
        return tempUrl
}

func main() {
        containerName := "container"
        objectName := "filename"

        c := swift.Connection{
                UserName: "username",
                ApiKey:   "api_key",
                AuthUrl:  "https://identity.api.rackspacecloud.com/v2.0/",
                Region:   "ORD",
        }

        err := c.Authenticate()
        if err != nil {
                panic(err)
        }

        _, headers, err := c.Account()
        if err != nil {
                panic(err)
        }

        tempKey, ok := headers["X-Account-Meta-Temp-Url-Key"]
        if !ok {
                panic("tempKey not found")
        }

        expiration := time.Now().Add(time.Second * 60)
        tempUrl := tempUrl(tempKey, c.StorageUrl, containerName, objectName, expiration)
        fmt.Println(tempUrl)
}