Shell script to wait for the prompt and pass user input-CodePudding

I need help in writing shell script. I am running one command which will ask for Username:, Email address:, Password:, Password (again):.

I need to write script which wait for prompt and feed the input to command. I tried with expect & send but seems not working.

[root@ip-1xx-xx-x-xx hue]$ sudo build/env/bin/hue  createsuperuser
Username: xyz 
Email address: [email protected]
Password: 
Password (again): 
Superuser created successfully.`

==============

Tried with below script:

#!/usr/bin/expect -f
  
cd /usr/lib/hue/
set timeout -1

sudo build/env/bin/hue createsuperuser

expect "Username: "
send -- "admin"

expect "Email address: "
send -- "[email protected]"

expect "Password: "
send -- "Password@123"

expect "Password (again): "
send -- "Password@123"

expect eof

The above script stuck at username

[root@ip-1xx-xx-x-xx ~]$ sh -x hueuser.sh 
  cd /usr/lib/hue/
  set timeout -1
  sudo build/env/bin/hue createsuperuser
Username:

CodePudding user response：

I believe the createsuperuser command asks for Username (leave blank to use ‘root’), not Username

Try using:

#!/usr/bin/expect -f
 
cd /usr/lib/hue/ 
set timeout -1
 
sudo build/env/bin/hue createsuperuser
 
expect "Username (leave blank to use ‘root’)"
send -- "admin"
 
expect "Email address:" 
send -- "[email protected]"

expect "Password:"
send -- "Password@123"

expect "Password (again):" 
send -- "Password@123"

expect eof

CodePudding user response：

Your expect script has a few problems still (even after you edited to remove the \rs in the expect strings which were also wrong).

First, you will need to spawn the command you are trying to run. If sudo works at all here, it will create a subprocess which runs outside of the control of expect.

Second, you need to send exactly the string you want to send, including the final newline. This is where \r is useful and necessary.

#!/usr/bin/expect -f
  
cd /usr/lib/hue/
set timeout -1

spawn sudo build/env/bin/hue createsuperuser

expect "Username: "
send -- "admin\r"

expect "Email address: "
send -- "[email protected]\r"

expect "Password: "
send -- "Password@123\r"

expect "Password (again): "
send -- "Password@213\r"

expect eof

A much better fix if you have control over the createsuperuser script is to change it so it doesn't require interactive I/O. See for example how the adduser command on Debian-based platforms wraps the lower-level useradd to allow it to be called from scripts with all the necessary arguments as command-line arguments. Also, man newusers for inspiration.