Expect fails but I don't see why - bash

Question

I have a bash script that gets info from Heroku so that I can pull a copy of my database. That script works fine in cygwin. But to run it in cron it halts because the shell that it uses halts as Heroku's authentication through Heroku Toolbelt.
Here is my crontab:
SHELL=/usr/bin/bash
5 8-18 * * 1-5 /cygdrive/c/Users/sam/work/push_db.sh >>/cygdrive/c/Users/sam/work/output.txt
I have read the Googles and the man page within cygwin to come up with this addition:
#!/usr/bin/bash
. /home/sam.walton/.profile
echo $SHELL
curl -H "Accept: application/vnd.heroku+json; version=3" -n https://api.heroku.com/
#. $HOME/.bash_profile
echo `heroku.bat pgbackups:capture --expire`
#spawn heroku.bat pgbackups:capture --expire
expect {
"Email:" { send -- "$($HEROKU_LOGIN)\r"}
"Password (typing will be hidden):" { send -- "$HEROKU_PW\r" }
timeout { echo "timed out during login"; exit 1 }
}
sleep 2
echo "first"
curl -o latest.dump -L "$(heroku.bat pgbackups:url | dos2unix)"
Here's the output from the output.txt
/usr/bin/bash
{
"links":[
{
"rel":"schema",
"href":"https://api.heroku.com/schema"
}
]
}
Enter your Heroku credentials. Email: Password (typing will be hidden): Authentication failed. Enter your Heroku credentials. Email: Password (typing will be hidden): Authentication failed. Enter your Heroku credentials. Email: Password (typing will be hidden): Authentication failed.
As you can see it appears that the output is not getting the result of the send command as it appears it's waiting. I've done so many experiments with the credentials and the expect statements. All stop here. I've seen few examples and attempted to try those out but I'm getting fuzzy eyed which is why I'm posting here. What am I not understanding?
Thanks to comments, I'm reminded to explicitly place my env variables in .bashrc:
[[ -s $USERPROFILE/.pik/.pikrc ]] && source "$USERPROFILE/.pik/.pikrc"
export HEROKU_LOGIN=myEmailHere
export HEROKU_PW=myPWhere
My revised script per #Dinesh's excellent example is below:
. /home/sam.walton/.bashrc echo $SHELL echo $HEROKU_LOGIN curl -H "Accept: application/vnd.heroku+json; version=3" -n https://api.heroku.com/
expect -d -c " spawn heroku.bat pgbackups:capture --expire --app gw-inspector expect {
"Email:" { send -- "myEmailHere\r"; exp_continue}
"Password (typing will be hidden):" { send -- "myPWhere\r" }
timeout { puts "timed out during login"; exit 1 } } " sleep 2 echo "first"
This should work but while the echo of the variable fails, giving me a clue that the variable is not being called, I am testing hardcoding the variables directly to eliminate that as a variable. But as you can see by my output not only is the echo yielding nothing, there is no clue that any diagnostics are being passed which makes me wonder if the script is even being called to run from expect, as well as the result of the spawn command. To restate, the heroku.bat command works outside the expect closure but the results are above. The result of the command directly above is:
/usr/bin/bash
{
"links":[
{
"rel":"schema",
"href":"https://api.heroku.com/schema"
}
]
}
What am I doing wrong that will show me diagnostic notes?

Answer 1

If you are going to use the expect code inside your bash script, instead of calling it separately, then you should have use the -c flag option.
From your code, I assume that you have the environmental variables HEROKU_LOGIN and HEROKU_PW declared in the bashrc file.
#!/usr/bin/bash
#Your code here
expect -c "
spawn <your-executable-process-here>
expect {
# HEROKU_LOGIN & HEROKU_PW will be replaced with variable values.
"Email:" { send -- "$HEROKU_LOGIN\r";exp_continue}
"Password (typing will be hidden):" { send "$HEROKU_PW\r" }
timeout { puts"timed out during login"; exit 1 }
}
"
#Your further bash code here
You should not use echo command inside expect code. Use puts instead. The option of spawning the process inside expect code will be more robust than spawning it outside.
Notice the use of double quotes with the expect -c flag. If you use single quotes, then bash script won't do any form of substitution. So, if you need bash variable substitution, you should use double quotes for the expect with -c flag.
To know about usage of -c flag, have a look at here
If you still have any issue, you can debug by appending -d with the following way.
expect -d -c "
our code here
"