oauth.go

package oauth

import (
	"github.com/aws/aws-sdk-go/aws"
	"github.com/google/uuid"
	"gitlab.bob.co.za/bob-public-utils/bobgroup-go-utils/encryption"
	"net/url"
	"strconv"
	"strings"
	"time"
)

type Oauth1 struct {
	ConsumerKey    string
	ConsumerSecret string
	AccessToken    string
	AccessSecret   string
}

func (auth Oauth1) GenerateAuthorizationHeader(method, requestUrl string) (AuthorizationValue *string, err error) {

	// Take the URL and get all its parts
	urlParts, err := url.Parse(requestUrl)
	if err != nil {
		return nil, err
	}

	// Get the query parameters from the URL and make it easier to work with
	rawParams, err := url.ParseQuery(urlParts.RawQuery)
	if err != nil {
		return nil, err
	}
	params := make(map[string]string)
	for key, _ := range rawParams {
		params[key] = rawParams.Get(key)
	}

	// Make a nonce
	nonce := strings.ReplaceAll(uuid.New().String(), "-", "")

	urlValues := url.Values{}
	urlValues.Add("oauth_nonce", nonce)
	urlValues.Add("oauth_consumer_key", auth.ConsumerKey)
	urlValues.Add("oauth_signature_method", "HMAC-SHA256")
	urlValues.Add("oauth_timestamp", strconv.Itoa(int(time.Now().Unix())))
	urlValues.Add("oauth_token", auth.AccessToken)
	urlValues.Add("oauth_version", "1.0")

	for k, v := range params {
		urlValues.Add(k, v)
	}

	// If there are any '+' encoded spaces replace them with the proper urlencoded version of a space
	parameterString := strings.Replace(urlValues.Encode(), "+", "%20", -1)

	// Build the signature
	signatureBase := strings.ToUpper(method) + "&" + url.QueryEscape(strings.Split(requestUrl, "?")[0]) + "&" + url.QueryEscape(parameterString)
	signingKey := url.QueryEscape(auth.ConsumerSecret) + "&" + url.QueryEscape(auth.AccessSecret)
	signature := encryption.Hash(signatureBase, signingKey)

	// Populate all the authorisation parameters
	authParams := map[string]string{
		"oauth_consumer_key":     url.QueryEscape(urlValues.Get("oauth_consumer_key")),
		"oauth_nonce":            url.QueryEscape(urlValues.Get("oauth_nonce")),
		"oauth_signature":        url.QueryEscape(signature),
		"oauth_signature_method": url.QueryEscape(urlValues.Get("oauth_signature_method")),
		"oauth_timestamp":        url.QueryEscape(urlValues.Get("oauth_timestamp")),
		"oauth_token":            url.QueryEscape(urlValues.Get("oauth_token")),
		"oauth_version":          url.QueryEscape(urlValues.Get("oauth_version")),
	}