Create an AWS SDK session from string credentials (say, you retrieve your creds from a database)

create_aws_session_string_creds.go

package main

import (
	"github.com/aws/aws-sdk-go/aws"
	"github.com/aws/aws-sdk-go/aws/credentials"
	"github.com/aws/aws-sdk-go/aws/session"
	"github.com/aws/aws-sdk-go/service/s3"
)

func main() {
	AWS_ACCESS_KEY_ID := ""
	AWS_SECRET_ACCESS_KEY := ""
	AWS_SECRET_ACCESS_TOKEN := ""

	creds := credentials.NewStaticCredentials(
		AWS_ACCESS_KEY_ID,
		AWS_SECRET_ACCESS_KEY,
		AWS_SECRET_ACCESS_TOKEN,
	)

	// Create Session
	sess := session.Must(session.NewSession(&aws.Config{
		Region:      aws.String(""),
		Credentials: creds,
	}))

	// Create a S3 client instance from a session
	sess := session.Must(session.NewSession())

	svc := s3.New(sess)
}