Although we can configure external endpoint via env variable (S3_ENDPOINT_URL), there should be a way to override authentication based on session token alone(principal based auth). Currently AWS_SESSION_TOKEN, still needs ACCESS and SECRET env vars.
If there is a provision to override Authorization header by populating an env var CUSTOM_AUTH_TOKEN, all client requests can go to endpoint with that header.
S5 is a great tool that can be expanded to cater to more auth mechanisms.
Although we can configure external endpoint via env variable (S3_ENDPOINT_URL), there should be a way to override authentication based on session token alone(principal based auth). Currently AWS_SESSION_TOKEN, still needs ACCESS and SECRET env vars. If there is a provision to override Authorization header by populating an env var CUSTOM_AUTH_TOKEN, all client requests can go to endpoint with that header. S5 is a great tool that can be expanded to cater to more auth mechanisms.