Re: [pgAdmin4][Patch] Feature #1447 SSH Tunnel - Mailing list pgadmin-hackers

From Akshay Joshi
Subject Re: [pgAdmin4][Patch] Feature #1447 SSH Tunnel
Date
Msg-id CANxoLDe8G6ZUdW3dWw9AFSLDGmo+sPS7cbTNNOfn1z484sVW4A@mail.gmail.com
Whole thread Raw
In response to Re: [pgAdmin4][Patch] Feature #1447 SSH Tunnel  (Victoria Henry <vhenry@pivotal.io>)
Responses Re: [pgAdmin4][Patch] Feature #1447 SSH Tunnel  (Dave Page <dpage@pgadmin.org>)
List pgadmin-hackers
Hi

On Wed, May 2, 2018 at 9:05 PM, Victoria Henry <vhenry@pivotal.io> wrote:
Hi Akshay,

Thanks for sending this updated patch.  The linter and tests are all passing.
- utils/driver/psycopg2/server_manager.py
  - Do we have Unit Tests around this?
 No. 

In our opinion, server_manager.py and connection.py should have tests.  Are you finding it difficult to add tests to these files?

   We will have to write test cases from scratch for both the files and it will take time, there is no point keeping these important feature(SSH Tunnel) on hold. We can create a separate task for this as we have for utility(Backup, Maintenance, Restore) modules.

   @Dave your thoughts on this?   

Sincerely,

Victoria & Joao


On Wed, May 2, 2018 at 5:58 AM, Akshay Joshi <akshay.joshi@enterprisedb.com> wrote:
Hi Joao


On Thu, Apr 26, 2018 at 10:26 PM, Joao De Almeida Pereira <jdealmeidapereira@pivotal.io> wrote:
Hi Akshay,

Some suggestions:
- browser/server_groups/servers/__init__py
  This file could have been split into separate functionalities. There is a chunk of changes for connect, why not move that out? Same thing for create. Do we really need to have full integrationy tests that do a HTTP request and connect to a real database to do make sure the functionalities are working? If we isolate these into their own actions we can more easily get more coverage on the code with tests that would be much faster and directed. The big advantage of this is that by reading the tests we can understand what the functions do. Self documenting code.

    If I understood you correctly, you want separate connect and create function for SSH Tunnel. If yes I don't think so we should move the SSH code and make the rest of the code duplicated in two different functions. For "create" function I have just added logic to pass SSH tunnel parameter while creating server object, encrypt the tunnel password and send it to connect method. For "connect" function encrypt the password and send it connect method as parameter. There is no point for such small changes we should create two separate functions.      

- utils/driver/psycopg2.py same comments has above

   I think you are talking about "utils/driver/psycopg2/connection.py". Same comments as above.  

- browser/server_groups/servers/static/js/server.js:
  - The patterm of using `m` for `model`? is a bad pattern, so why not change it?

      Fixed. 
  - We could extract the model creation from this file. This will allow us to add some tests around disabled methods that are a bit everywhere
       Model creation is the main functionality of the "server.js" (or any other module file), code readability wise it should be in the same file. If we will do it for rest of the modules then there are so many java script files where model creation is in separate file.    

  - We could also convert this file to ES6

     I am new to this, so will need to learn first. We can create a separate task to do this.   

- utils/driver/psycopg2/server_manager.py
  - Do we have Unit Tests around this?

      No. 
  - Maybe this SSH part could be isolated into it's own class, as it is not 100% related to the class in question. We need to use it but is is not part of the ServerManager domain 

      According to me SSH Tunnel parameters is the part of server manager as we do have other parameters of Server dialog. We can isolate the SSH part in other class, but most of the modules (including Server module) have access to the ServerManager. If we will isolate that part then anyways we will have to write wrapper functions in ServerManager which will eventually call functions of new SSH class. 

      As one ServerManager object belongs to one server, similarly one SSH Tunnel belongs to one server. When SSH tunnel gets created it will return local bind port, where rest of the communication should be done on local host and the local bind port return by the "SSHTunnelForwarder" class, so that need to be in the ServerManager

     Considering above I have kept that logic in ServerManager
 

- JS template. Eventually I would like to see if completely removed, and the information that we are generating using the template can be passed to the frontend via a Ajax call as an example( Do not think this is the time to do it.)

- start_running_query.py 
 - we could enrich the tests of this functionality

     Added one test case for SSHTunnelConnectionLost 


And example of naming is for example on psycopg2/connection.py
mgr = self.manager
How much to we win by having this variable name versus manager = self.manager or even using the self.manager?

   Fixed. Replace "mgr" with "manager" almost at 69 places in the file.

   Attached is the modified patch. Please review it.


This is not for you in specific, but for @hackers in general:
The book https://www.amazon.com/dp/0132350882/ is a pretty nice book that gives you an introduction to clean code, that is self documenting and that is much easily maintained.

Thanks
Joao

On Thu, Apr 26, 2018 at 3:44 AM Akshay Joshi <akshay.joshi@enterprisedb.com> wrote:
Hi Hackers, 

Attached is the updated patch which includes documentation of the feature and also updated screenshots of server dialog with new "SSH Tunnel" tab.

On Wed, Apr 25, 2018 at 11:45 AM, Akshay Joshi <akshay.joshi@enterprisedb.com> wrote:
Hi Joao

On Tue, Apr 24, 2018 at 10:04 PM, Joao De Almeida Pereira <jdealmeidapereira@pivotal.io> wrote:
Hi Akshay,

After looking through the patch we found some one letter variable names and this is a regression on what we have been trying to accomplish in the last year.

An objective that we have for pgAdmin source code is to increase the testability of it and make it more readable. If we keep on adding one letter variables and if we continue adding code to already convoluted source files it is going to be very hard to achieve this objective.

      At my level I have tried not to give one letter variable names. Are you talking about the variable "m" in server.js file which represents the Model? If yes then I have followed the code written for whole schema and I thought we have to maintain the consistency, so use that as it is. Apart from that I haven't seen any other one letter variable, please correct me so that I'll rename it. 

Our recommendations for this change are:
- Name the variables with comprehensive names
      Can you please suggest from the patch.
 
- Extract functions where we can and try to wrap some tests around them (ex: the javascript disabled functions)

    I have tried to do that too, if you can see the "server/__init__.py" file I have created "get_response_for_password" function to remove redundant code. Based on the condition it will return the json response.
 
- We really need to find a better pattern than templated Javascript to pass information from the backend to the frontend 
- When changing a piece of code, if we see code that is confusing or that is hard to read, we should refactor instead of adding to the pattern.

    Please elaborate more with respect to my patch, which part of code should required modification?  

Thanks
Victoria & Joao


On Tue, Apr 24, 2018 at 10:13 AM Akshay Joshi <akshay.joshi@enterprisedb.com> wrote:
Hi Hackers

As per suggestion by Dave, I have moved "Advanced" tab at the last for Server dialog. Attached is the modified patch.

On Mon, Apr 23, 2018 at 7:32 PM, Anthony Emengo <aemengo@pivotal.io> wrote:
For what it is worth, I manually verified that the feature worked, as well as looked through the code.

I'd like to see end-to-end testing for regression sake, but it's hard to so at this moment.

- Anthony and Joao.

On Mon, Apr 23, 2018 at 5:09 AM, Akshay Joshi <akshay.joshi@enterprisedb.com> wrote:


On Mon, Apr 23, 2018 at 1:30 PM, Dave Page <dpage@pgadmin.org> wrote:
Hi

On Thu, Apr 19, 2018 at 6:56 PM, Anthony Emengo <aemengo@pivotal.io> wrote:
Hey Akshay 

This patch passed our test pipelines.

Did you test the feature and//or review the code and tests? Passing the tests is great, *if* the whole feature is covered (and the nature of this patch will make that quite difficult, maybe impossible to do without external infrastructure and config).

    Agreed, it's been difficult to write test case to test the complete feature. 
 

Anthony and Victoria

On Thu, Apr 19, 2018 at 1:48 AM, Akshay Joshi <akshay.joshi@enterprisedb.com> wrote:
Hi Hackers 

I have implemented the SSH Tunnel support using https://pypi.org/project/sshtunnel/ python package. Added "SSH Tunnel" Tab in server dialog. This implementation supports user name /password and private/public key combination with Passphrase to crate SSH Tunnel. I have added regression test case to add server using SSH Tunnel options.

The given python package(https://pypi.org/project/sshtunnel/) support Python version 2.7, 3.4+.
It uses Paramiko (Python implementation of SSHv2 protocol) which actually drops support for Python 2.6. So I have added SUPPORT_SSH_TUNNEL parameter in config.py which checks the python version and set the flag accordingly. In case of Python 2.6, 3.0, 3.1, 3.2 and 3.3 control on the "SSH Tunnel" tab of server dialog will be disabled.

Please review it, and if looks good please commit the code.     

--
Akshay Joshi
Sr. Software Architect






--
Dave Page
Blog: http://pgsnake.blogspot.com
Twitter: @pgsnake

EnterpriseDB UK: http://www.enterprisedb.com
The Enterprise PostgreSQL Company



--
Akshay Joshi
Sr. Software Architect






--
Akshay Joshi
Sr. Software Architect





--
Akshay Joshi
Sr. Software Architect





--
Akshay Joshi
Sr. Software Architect





--
Akshay Joshi
Sr. Software Architect


Phone: +91 20-3058-9517
Mobile: +91 976-788-8246




--
Akshay Joshi
Sr. Software Architect


Phone: +91 20-3058-9517
Mobile: +91 976-788-8246

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