fix: [ISSUE] sftp connector do not work

Describe the bug

testing sftp connector failed

unstract-backend                | [2025-03-18 10:09:23 +0000] [20] [DEBUG] POST /api/v1/unstract/mock_org/test_connectors/
unstract-backend                | INFO : [2025-03-18 10:09:23,184]{module:base process:20 thread:134940039579328 request_id:9d681bd3d761458284d82c1b0fcde06d} :- DB connection (ID: 134939447194624) is established or reused.
unstract-backend                | INFO : [2025-03-18 10:09:23,193]{module:connector_processor process:20 thread:134940039579328 request_id:9d681bd3d761458284d82c1b0fcde06d} :- Testing connector: sftp|e68fa828-2988-4cce-9e3d-4285348e3227
unstract-backend                | INFO : [2025-03-18 10:09:23,193]{module:connector_processor process:20 thread:134940039579328 request_id:9d681bd3d761458284d82c1b0fcde06d} :- Fetching connector list for id with sftp|e68fa828-2988-4cce-9e3d-4285348e3227
unstract-backend                | ERROR : [2025-03-18 10:09:23,202]{module:exception process:20 thread:134940039579328 request_id:9d681bd3d761458284d82c1b0fcde06d} :- POST http://frontend.unstract.mydomain.intr/api/v1/unstract/mock_org/test_connectors/ 400 TestConnectorInputError()
unstract-backend                | Bad Request: /api/v1/unstract/mock_org/test_connectors/
unstract-backend                | WARNING : [2025-03-18 10:09:23,204]{module:log process:20 thread:134940039579328 request_id:9d681bd3d761458284d82c1b0fcde06d} :- Bad Request: /api/v1/unstract/mock_org/test_connectors/
unstract-proxy                  | 172.16.99.6 - - [18/Mar/2025:10:09:23 +0000] "POST /api/v1/unstract/mock_org/test_connectors/ HTTP/1.1" 400 146 "-" "-" 53270 "backend@file" "http://host.docker.internal:8000/" 63ms
unstract-backend                | 172.28.0.1 - - [18/Mar/2025:10:09:23 +0000] "POST /api/v1/unstract/mock_org/test_connectors/ HTTP/1.1" 400 146 "http://frontend.unstract.mydomain.intr/mock_org/workflows/2b235aa6-9742-4797-8197-60a92e39caed" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/133.0.0.0 Safari/537.36"
unstract-backend                | [2025-03-18 10:09:23 +0000] [20] [DEBUG] POST /api/v1/unstract/mock_org/logs/
unstract-backend                | INFO : [2025-03-18 10:09:23,315]{module:base process:20 thread:134939995539136 request_id:8927a2b09d7a475c9461ae1f3b692cce} :- DB connection (ID: 134939447194624) is established or reused.
unstract-proxy                  | 172.16.99.6 - - [18/Mar/2025:10:09:23 +0000] "POST /api/v1/unstract/mock_org/logs/ HTTP/1.1" 200 54 "-" "-" 53271 "backend@file" "http://host.docker.internal:8000/" 45ms
unstract-backend                | 172.28.0.1 - - [18/Mar/2025:10:09:23 +0000] "POST /api/v1/unstract/mock_org/logs/ HTTP/1.1" 200 54 "http://frontend.unstract.mydomain.intr/mock_org/workflows/2b235aa6-9742-4797-8197-60a92e39caed" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/133.0.0.0 Safari/537.36"
unstract-backend                | [2025-03-18 10:09:23 +0000] [20] [DEBUG] GET /api/v1/socket/
unstract-proxy                  | 172.16.99.219 - - [18/Mar/2025:10:09:23 +0000] "GET /api/v1/socket/?EIO=4&transport=websocket HTTP/1.1" 400 25 "-" "-" 53272 "backend@file" "http://host.docker.internal:8000/" 5ms
unstract-backend                | 172.28.0.1 - - [18/Mar/2025:10:09:23 +0000] "GET /api/v1/socket/?EIO=4&transport=websocket HTTP/1.1" 400 25 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/134.0.0.0 Safari/537.36"
unstract-celery-beat            | INFO : [2025-03-18 10:09:24,874]{module:base process:1 thread:136082605570944 request_id:none} :- DB connection (ID: 136081608849664) is established or reused.

on target, no trace of connexion

To reproduce

fill information in buil/workflows sftp connector

Expected behavior

Test sftp ok

Environment details

Name LLM Embedding Model Vector Database Text Extractor
ollama-deepseek-r1 ollama-deepseek-r1 ollama-emb-deepseek-r1 pg-vdb-1 unstructured-io-1

• Version: latest , opensource version

Distributor ID: Ubuntu
Description: Ubuntu 24.04.1 LTS
Release: 24.04

Screenshots

Start at the POST /api/v1/unstract/mock_org/test_connectors/ entry point shown in the logs and trace the SFTP connector test flow. Check how the connector input reaches the target connection, then reproduce the failure and confirm that testing the configured SFTP connector returns success and connects to the target.