Description:
The Basic Authentication mechanism is not working as expected, and this behaviour is observed in SI-4.X versions when tested locally.
For example, when we use the http-call sink method with Basic Auth enabled as shown below, the Base64 encoded username and password is getting malformed.

@sink(type='http-call', sink.id='D1', publisher.url='http://localhost:8281/foobar/1.0', method='POST', basic.auth.username='admin', basic.auth.password='admin',
headers='Content-Type: application/json', ...,

When we checked the wirelogs from the backend service, we observed that the Authorization header value being sent to the backend was incorrect,
"Authorization: Basic UnpooledHeapByteBuf(ridx: 0, widx: 11, cap: 11/11)[\r][\n]"
Seems like there is an issue with the Base64 encoding of the Authorization header at [1]. The encoded header is in bytes and it needs to be converted to string through byte methods which causes the incorrect value to get assigned as the Authorization header. Since the encoded username and password value are invalid, the http-call sink method fails.

[1]

1. Create a backend with Basic Auth enabled
2. Create a Siddhi App which calls the above backend using an http-call sink method with Basic Auth.
3. When invoked, the Basic Auth mechanism will fail due to the improper encoded username and password.

Affected Product Version:

• Streaming-Integrator-4.X.X