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ssh running a command gives different results to running it locally

I have a python script that uses Popen to create an appium server for a simulator on a mac
self.appium_process = subprocess.Popen(["/usr/local/bin/appium", "-a", self.ip, "--nodeconfig", self.node_file_path, "--relaxed-security", "-p", str(appium_port), "-dc", default_capabilities], stdout=log_file, stderr=subprocess.STDOUT)
I created a bash shell script that calls the python script. When I run the script from the local box it works and the appium logs show the connection.
I need to run this remote via ssh however. So I use the following to call the script:
ssh 10.18.66.99 automation_fw/config/testscript.sh
This, however, always ends up with the log showing:
env: node: No such file or directory
I checked and the node app has an extra slash before its called:
$ which node
/usr/local/bin//node
$
I tried changing the path on the machine but no change. How can I get this to run from ssh in the same way as it can run locally on that same box
A

When you are running a command vis SSH you are not starting what's called a login shell (more about that here).
From the details you've shared, I would say it's some thing in your environment (running outside a logged-in shell), more specifically a problem with your $PATH variable. You might want to check /etc/environment or similar paths (depending on your Linux flavour) for the wrong value.

How to run a python script from local machine on a remote server and display the outputs live?

The only solution i found was this :
cat MyScript.py | ssh username#ip_addr python -
the problem with this is that it wont show the outputs of that script live, it waits until the program is finished and then it displays the output
I'm using scapy with in this script and sniff packets with it, and i have to run this on that remote server (and no, i cant copy it there or write it there)
so what is the solution? how can i view the outputs of a script live in my command line?
I'm using windows 10.
Important note: also i think ssh is using some sort of buffering, and sends the output after the amount of printed stuff gets more than buffer, since when the output is very large it does show part of it suddenly, i want the output of that function to come to my computer as soon as possible, not after reaching a buffer or something

You should first send the file to your remote machine using
scp MyScript.py username#ip_addre:/path/to/script
then SSH to your remote machine using
ssh username#ip_addr
ANd finally, you run you script normally
python path/to/MyScript.py
EDIT
To execute your script directly without copying it to the remote machine, use this command:
ssh user#ip_addr 'python -s' < script.py

SVN SSL Certificate Untrusted via Python Script

I have a strange scenario going on at the moment. When I issue an svn info TXN REPO command on our build server (separate from the SVN server), it works as expected and displays the relevant information to the console.
However when I script it using Python, and specifically, Popen from the subprocess module, it prints a message svn: E230001: Server SSL certificate untrusted to the standard error (console).
What I've tried:
Using --non-interactive and --trust-server-cert flags within the script call.
Passing a username/password within the svn info call via the script.
The above two don't seem to take effect, and the same error as above is spat out. However, manually running the same command from the command prompt succeeds with no problems. I assume it might be something to do with python opening up a new session to the SVN server, and that session isn't a "trusted" connection? But I can't be sure.
Our SVN server is on a windows machine and is version 1.8.0
Our build server is a windows machine running Jenkins version 2.84. Jenkins executes a batch script which kicks off the Python script, performing the above task.
Command: svn_session = Popen("svn info --non-interactive --trust-server-cert --no-auth-cache -r %s %s" % (TXN, REPOS), stdout=PIPE, stderr=PIPE, shell=True)
** Edit **
When I copy and paste the python line from the script into the interactive python shell on the same server, the command works as expected also. So the issue is how the script is executing the command, rather than the command itself or how Python runs that command.
**
Has anyone come across this before?

In case anyone is looking at this in the future. Panda Pajama has given a detailed answer to this..
SVN command line in jenkins fails due to server certificate mismatch

Python ssh with fabric, code 127

I'm trying to use fabric in python to send commands to a program on another machine.
This code works fine:
from fabric.api import env, run
env.host_string = 'xxx.xxx.xxx.xxx'
env.user = 'username'
env.password = 'password'
run('ls')
But when running
run('rostopic list')
I get
Warning: run() received nonzero return code 127 while executing 'rostopic list'!
'/bin/bash: rostopic: command not found'
However on the machine itself if I run
rostopic list
it runs as it's supposed to
I'm not sure how to proceed and I don't understand why it's not working with fabric. FYI I tried implementing this with paramiko but I also run into problems, however it works fine with pxssh. The issue is that I need this to work on Windows and pxssh isn't compatible. How can I make this command work with fabric?

From the comments you've made about the pathing issues, it sounds like you will need to use some combination of the path, cd, and/or prefix context managers in order to run ROS (Robot Operating System) commands over an SSH connection. You might also wish to troubleshoot by getting Fabric completely out of the picture, and instead work on getting the command to work via ssh -t, like so:
$ ssh user#machine -t "cd /my/home/directory && /opt/ros/indigo/bin/rostopic list"
An example using context managers with Fabric would look like this:
with path('/opt/ros/indigo/bin/'):
with prefix('always run this command'):
with cd('/my/special/directory'):
run('rostopic list')
That's pretty contrived, but hopefully illustrates the point. Regardless, I would first make sure that you can run the command via ssh -t. Solving that problem will likely lead you to the correct way to make this happen with Fabric.
As a side/related consideration: is this a virtual environment on your remote machine? You could use the prefix context manager to activate it, like so:
with prefix('/opt/ros/indigo/bin/activate'):
run('rostopic list')
Or using ssh -t, you could execute:
$ ssh user#machine -t "/opt/ros/indigo/bin/activate && rostopic list"

which user's privileges python program uses to execute command via subprocess?

I have stabled password less login between two ubuntu system then I run following command
$scp file user#hostname2:/tmp/
it works fine and I got file transferred without asking for password.
however when I try to execute the same through following python statement-
subprocess.check_output(['scp', file, r'user#hostname2:/tmp/'])
I am not able to copy files to remote computer, so I am bit curious about which user's privileges python program uses to execute command via subprocess ?
How can I debug such programs ?