Adding example for rdsutils and also adding scheme if one wasn't prov…

…ided when creating authentication tokens

example/service/rds/rdsutils/authentication/README.md

@@ -0,0 +1,15 @@
+# Example
+
+This is an example using the AWS SDK for Go to create an Amazon RDS DB token using the
+rdsutils package.
+
+# Usage
+
+```sh
+go run iam_authetnication.go <region> <db user> <db name> <endpoint to database> <iam arn>
+```
+
+Output:
+```
+Successfully opened connection to database
+```

example/service/rds/rdsutils/authentication/iam_authentication.go

@@ -0,0 +1,45 @@
+package main
+
+import (
+	"database/sql"
+	"fmt"
+	"log"
+	"os"
+
+	"github.com/go-sql-driver/mysql"
+
+	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/aws/credentials/stscreds"
+	"github.com/aws/aws-sdk-go/aws/session"
+	"github.com/aws/aws-sdk-go/service/rds/rdsutils"
+)
+
+// Usage ./iam_authentication <region> <db user> <db name> <endpoint to database> <iam arn>
+func main() {
+	if len(os.Args) < 5 {
+		log.Println("USAGE ERROR: go run concatenateObjects.go <region> <endpoint to database> <iam arn>")
+		os.Exit(1)
+	}
+
+	awsRegion := os.Args[1]
+	dbUser := os.Args[2]
+	dbName := os.Args[3]
+	dbEndpoint := os.Args[4]
+	awsCreds := stscreds.NewCredentials(session.New(&aws.Config{Region: &awsRegion}), os.Args[5])
+	authToken, err := rdsutils.BuildAuthToken(dbEndpoint, awsRegion, dbUser, awsCreds)
+
+	// Create the MySQL DNS string for the DB connection
+	// user:password@protocol(endpoint)/dbname?<params>
+	dnsStr := fmt.Sprintf("%s:%s@tcp(%s)/%s?tls=true",
+		dbUser, authToken, dbEndpoint, dbName,
+	)
+
+	driver := mysql.MySQLDriver{}
+	_ = driver
+	// Use db to perform SQL operations on database
+	if _, err = sql.Open("mysql", dnsStr); err != nil {
+		panic(err)
+	}
+
+	fmt.Println("Successfully opened connection to database")
+}

service/rds/rdsutils/connect.go

@@ -12,11 +12,10 @@ import (
 // BuildAuthToken will return a authentication token for the database's connect
 // based on the RDS database endpoint, AWS region, IAM user or role, and AWS credentials.
 //
-// Endpoint consists of the scheme, hostname, and port. IE scheme://{hostname}[:port]
-// of the RDS database. Region is the AWS region the RDS database is in and where
-// the authentication token will be generated for. DbUser is the IAM user or role
-// the request will be authenticated for. The creds is the AWS credentials
-// the authentication token is signed with.
+// Endpoint consists of the hostname and port, IE hostname:port, of the RDS database.
+// Region is the AWS region the RDS database is in and where the authentication token
+// will be generated for. DbUser is the IAM user or role the request will be authenticated
+// for. The creds is the AWS credentials the authentication token is signed with.
 //
 // An error is returned if the authentication token is unable to be signed with
 // the credentials, or the endpoint is not a valid URL.
@@ -38,6 +37,11 @@ import (
 // See http://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/UsingWithRDS.IAMDBAuth.html
 // for more information on using IAM database authentication with RDS.
 func BuildAuthToken(endpoint, region, dbUser string, creds *credentials.Credentials) (string, error) {
+	// the scheme is arbitrary and is only needed because validation of the URL requires one.
+	if !(strings.HasPrefix(endpoint, "http://") || strings.HasPrefix(endpoint, "https://")) {
+		endpoint = "https://" + endpoint
+	}
+
 	req, err := http.NewRequest("GET", endpoint, nil)
 	if err != nil {
 		return "", err

service/rds/rdsutils/connect_test.go

@@ -10,12 +10,30 @@ import (
 )
 
 func TestBuildAuthToken(t *testing.T) {
-	endpoint := "https://prod-instance.us-east-1.rds.amazonaws.com:3306"
-	region := "us-west-2"
-	creds := credentials.NewStaticCredentials("AKID", "SECRET", "SESSION")
-	user := "mysqlUser"
+	cases := []struct {
+		endpoint      string
+		region        string
+		user          string
+		expectedRegex string
+	}{
+		{
+			"https://prod-instance.us-east-1.rds.amazonaws.com:3306",
+			"us-west-2",
+			"mysqlUser",
+			`^prod-instance\.us-east-1\.rds\.amazonaws\.com:3306\?Action=connect.*?DBUser=mysqlUser.*`,
+		},
+		{
+			"prod-instance.us-east-1.rds.amazonaws.com:3306",
+			"us-west-2",
+			"mysqlUser",
+			`^prod-instance\.us-east-1\.rds\.amazonaws\.com:3306\?Action=connect.*?DBUser=mysqlUser.*`,
+		},
+	}
 
-	url, err := rdsutils.BuildAuthToken(endpoint, region, user, creds)
-	assert.NoError(t, err)
-	assert.Regexp(t, `^prod-instance\.us-east-1\.rds\.amazonaws\.com:3306\?Action=connect.*?DBUser=mysqlUser.*`, url)
+	for _, c := range cases {
+		creds := credentials.NewStaticCredentials("AKID", "SECRET", "SESSION")
+		url, err := rdsutils.BuildAuthToken(c.endpoint, c.region, c.user, creds)
+		assert.NoError(t, err)
+		assert.Regexp(t, c.expectedRegex, url)
+	}
 }