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Published 20 hours ago • verified publisher icon tableau

[BUG] With the environment variable "http_proxy", the connections with the "Denodo JDBC" connector go through the proxy but they should not

Open carlossc opened this issue 2 years ago • 0 comments

Describe the bug

When a user sets the environment variable http_proxy, the connections to Denodo using the "Denodo JDBC" connector (the one based on the SDK, which uses our JDBC driver) go through the proxy but they should not. This is unexpected since our driver does not open HTTP connections.

I guess the "Java layer" of Tableau is reading this environment variable and doing "something" to all the traffic.

Important: consider this. When you set this environment variable, this happens as well:

1. This works: connecting from a simple Java class that opens a connection to Denodo with the Denodo JDBC driver and executes a query. 2. This works: connecting to Denodo from DBeaver and DBVisualizer, using the Denodo JDBC driver. 3. This fails: connecting from Tableau Desktop to Oracle with the Oracle JDBC connector (the driver tries to connect through the proxy) so it is does not seem to be something specific to our driver. 4. This works: the connection from Tableau Desktop to Denodo using the native Denodo connector. This native connector uses either the PostgreSQL ODBC driver or the Denodo ODBC driver.

How to reproduce this

  1. Go to the Tableau Gallery and download the connector "Denodo JDBC" (https://extensiongallery.tableau.com/products/303).

  2. Follow the instructions to install the connector (note you have to download the Denodo JDBC driver).

I can provide a host with a Denodo server running to test this if you do not have one readily available but I do not want to write the credentials here).

  1. Connect to the Denodo server using the Denodo JDBC by Denodo Technologies. This works.

  2. Close Tableau Desktop

  3. Define the environment variable http_proxy. Screenshot: screenshot

  4. Start Tableau Desktop and connect to Denodo using the same connector. This fails. Screenshot of the error: screenshot of the error

  5. Connect to Oracle using the Oracle JDBC connector and I get a similar error. Screenshot: error_oracle. This works fine without the variable http_proxy.

Desktop (please complete the following information):

  • OS: Windows 10.
  • Tableau Version: Tableau Desktop 2022.2.

About you: Name: Carlos Santos Canelles Company: Denodo Technologies.

This problem affects a mutual customer (I can provide the name offline). This customer opened a ticket with Denodo and with Tableau (case #08371475) but they insist we should look into this.

carlossc avatar Aug 19 '22 07:08 carlossc