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Why is crontab not running a python script

This is how I configure crontab (by using crontab -e)
* * * * * /home/jeff/Desktop/scripts/job_pull_queue.sh >> /home/jeff/Desktop/scripts/log.txt
This is the content of /home/jeff/Desktop/scripts/job_pull_queue.sh
#!/bin/bash
echo "Running job_pull_queue.sh # $(date)"
cd /home/jeff/Documents/code/some_project
echo $(printenv)
/home/jeff/miniconda3/bin/python -m util.main
Now the problem is, when running ./job_pull_queue.sh in the terminal, it works, but I can tell from the log file that crontab never executes that last line /home/jeff/miniconda3/bin/python -m util.main (I can see the result from the previous echo in the log file, but not the python script itself), what happened? How do I fix it?
Update: here's the result from printenv when ran by crontab
SHELL=/bin/sh PWD=/home/jeff/Documents/code/some_project LOGNAME=jeff HOME=/home/jeff LANG=en_US.UTF-8 SHLVL=0 PATH=/usr/bin:/bin OLDPWD=/home/jeff _=/usr/bin/printenv

Ok...
My Python script reads several env variables from my user profile, and of course, these variables don't exist when crontab is running the script...
And I don't have detection/logging in place so I didn't know env variables are missing.

Can I create a script, "Virtual Environment" and run it in crontab?

They help me, they know I need to run a script to start the services, I use Django with Python and ubuntu server.
I have been seeing many examples in crontab, which I will use, every time I restart the server, I run the Script, which contains the command to run the virtual environment and in addition to the command "python3 manage.py runserver_plus", apart was to see restart the server all nights, I was also successful with crontab, but I can't execute what the script contains. They can help me, I am not very expert, but I managed to do something.
Is it the path of the script?
Tried running the command directly, got no results.
I write the following.
root#server:/home/admin-server# pwd
/home/admin-server
root#server:/home/admin-server# ls -l
drwxrwxr 3 admin-server admin-server 4096 Nov 20 17:25 control_flota
-rwxr--r-- 1 root root. 141 Nov 20 18:00 server_script.sh
Script new
I still have no results: /, I don't know why?
#!bin/bash
echo "Welcome"
cd /home/admin-server/control_flota/
source venvp1/bin/activate
echo "Thanks"

You can activate the Virtual Environment from within the shell script, prior to running any manage.py commands
#!/bin/bash
cd /your_code_directory
source env/bin/activate
python ./manage.py runserver_plus
Ensure you save the file with the .sh extension, then give it execute rights:
chmod u+x your_script.sh
You should then be able to call from cron; sudo cron if you run into permissions issues

crontab bash script execution - Raspberry Pi

I have a bash script that I'm using to execute a python file with a specific version of Python (3.6). The Bash script is currently located on my desktop (/home/pi/Desktop/go.sh)
#!/bin/bash
python3.6 /home/pi/scriptDir/myScript.py
Here is my crontab entry, when I do crontab -l (note, I've deleted my other jobs)
* * * * * bash /home/pi/Desktop/go.sh # JOB_ID_3
When I run this file using the command line or from the GUI it executes properly.
When I have crontab do it, nothing happens.
Both my python file and the bash script are executable. chmod +x
Is there something obvious I'm missing?
**my python script does depend on other files in the same script directory, could that be the issue?

Here's what got it working for me. I was not using the full path to my python install. Unless you log the bash file there's no indication that you have an issue.
This is my bash file now. echo's were just to determine that I was indeed running the bash file.
#!/bin/bash
echo started
/home/pi/Python-3.6.0/python home/pi/myScriptFolder/myScript.py
echo finished
To break down the line executing the script:
/home/pi/Python-3.6.0/python - is where python 3.6.0 is installed on my Pi, it could be different for you. home/pi/myScriptFolder/myScript.py is the script I want to run.
And here is my cron statement:
*/15 * * * * bash /home/pi/Desktop/go.sh > /home/pi/Desktop/clog.log 2>&1 -q -f
Breaking down this line:
*/15 * * * * is the cron time, in this case every 15 mins. bash /home/pi/Desktop/go.sh specifies to run a bash file and the directory of that file. > /home/pi/Desktop/clog.log 2>&1 -q -f this last section creates a log file named clog.log so you can see what's going on.
The key here was not just logging the go.sh bash file execution, but adding the 2>&1 -q -f to the end of the log request. Before I did that there was no indication of a problem, afterwards I was getting the python files error returned into the log file.

Cron jobs are surprisingly tricky. Aside from working directory ( which you'd have to set somewhere), you also need to handle environment setup ( $PATH, for example).
Start by redirecting your shell script's standard output and error to a log file so you can get feedback.

cronjob error in OSX: "no path for address"

I tried running a Python script using cronjob but I get the following error:
cron[44405]: no path for address 0x10ff7a000
in grep cron /var/log/system.log
When I ran the script without using cronjob it worked:
/usr/bin/python  /Users/anuj/Desktop/message.py
I tried adding the cron job using $sudo crontab. This is the CRON script:
*/1 11-17 * * 1-7 /usr/bin/python  /Users/anuj/Desktop/message.py
Both paths are correct for root mode and user mode as I am running cron with sudo.

try to create file like message.sh
inside it run your .py file
#!/bin/sh
python path/to/python_script.py
and make this file executable with chmod a+x message.sh
*/1 11-17 * * 1-7 path/to/message.sh 2>&1

Crontab not restarting process

I am trying to setup a crontab to run 6 python data scrapers. I am tired of having to restart them manually when one of them fails. When running the following:
> ps -ef | grep python
ubuntu 31537 1 0 13:09 ? 00:00:03 python /home/ubuntu/scrapers/datascraper1.py
etc... I get a list of the datascrapers 1-6 all in the same folder.
I edited my crontab like this:
sudo crontab -e
# m h dom mon dow command
* * * * * pgrep -f /home/ubuntu/scrapers/datascraper1.py || python /home/ubuntu/scrapers/datascraper1.py > test.out
Then I hit control+X to exit and hit yes to save as /tmp/crontab.M6sSxL/crontab .
However it does not work in restarting or even starting datascraper1.py whether I kill the process manually or if the process fails on its own. Next, I tried reloading cron but it still didn't work:
sudo cron reload
Finally I tried removing nohup from the cron statement and that also did not work.
How can I check if a cron.allow or cron.deny file exists?
Also, do I need to add a username before pgrep? I am also not sure what the "> test.out" is doing at the end of the cron statement.
After running
grep CRON /var/log/syslog
to check to see if cron ran at all, I get this output:
ubuntu#ip-172-31-29-12:~$ grep CRON /var/log/syslog
Jan 5 07:01:01 ip-172-31-29-12 CRON[31101]: (root) CMD (pgrep -f datascraper1.py ||
python /home/ubuntu/scrapers/datascraper1.py > test.out)
Jan 5 07:01:01 ip-172-31-29-12 CRON[31100]: (CRON) info (No MTA installed, discarding output)
Jan 5 07:17:01 ip-172-31-29-12 CRON[31115]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Jan 5 08:01:01 ip-172-31-29-12 CRON[31140]: (root) CMD (pgrep -f datascraper1.py || python /home/ubuntu/scrapers/datascraper1.py > test.out)
Since there is evidence of Cron executing the command, there must be something wrong with this command, (note: I added the path to python):
pgrep -f datascraper1.py || /usr/bin/python /home/ubuntu/scrapers/datascraper1.py > test.out
Which is supposed to check to see if datascaper1.py is running, if not then restart it.
Since Cron is literally executing this statement:
(root) CMD (pgrep -f datascraper1.py || python /home/ubuntu/scrapers/datascraper1.py > test.out)
aka
root pgrep -f datascraper1.py
Running the above root command gives me:
The program 'root' is currently not installed. You can install it by typing:
sudo apt-get install root-system-bin
Is there a problem with Cron running commands from root?
Thanks for your help.

First of all, you need to see if cron is working at all.
Add this to your cron file (and ideally delete the python statement for now, to have a clear state)
* * * * * echo `date` >>/home/your_username/hello_cron
This will output the date in the file "hello_cron" every minute. Try this, and if this works, ie you see output every minute, write here and we can troubleshoot further.
You can also look in your system logs to see if cron has ran your command, like so:
grep CRON /var/log/syslog
Btw the >test.out part would redirect the output of the python program to the file test.out. I am not sure why you need the nohup part - this would let the python programs run even if you are logged out - is this what you want?
EDIT: After troubleshooting cron:
The message about no MTA installed means that cron is trying to send you an e-mail with the output of the job but cannot because you dont have an email programm installed:
Maybe this will fix it:
sudo apt-get install postfix
The line invoking the python program in cron is producing some output (an error) so it's in your best interests to see what happens. Look at this tutorial to see how to set your email address: http://www.cyberciti.biz/faq/linux-unix-crontab-change-mailto-settings/
Just in case the tutorial becomes unavailable:
MAILTO:youremail#example.com

You need to add python home to your path at the start of the job, however you have python set up. When you're running it yourself and you type python, it checks where you are, then one level down, then your $PATH. So, python home (where the python binary is) needs to be globally exported for the user that owns the cron (so, put it in a rc script in /etc/rc.d/) or, you need to append the python home to path at the start of the cron job. So,
export PATH=$PATH:<path to python>
Or, write the cron entry as
/usr/bin/python /home/ubuntu/etc/etc
to call it directly. It might not be /usr/bin, run the command
'which python'
to find out.
The 'No MTA' message means you are getting STDERR, which would normally get mailed to the user, but can't because you have no Mail Transfer Agent set up, like mailx, or mutt, so no mail for the user can get delivered from cron, so it is discarded. If you'd like STDERR to go into the log also, at the end, instead of
"command" > test.out
write
"command" 2>&1 > test.out
to redirect STDERR into STDOUT, then redirect both to test.out.