sed regex not working in shell script

Question

Given:

~$ cat .test-profile
export [email protected]
export MONGODB_URI='mongodb+srv://administrator:[email protected]/test?retryWrites=true&w=majority'

I wrote the following shell script to replace the variable values:

BASH_PROFILE="$HOME/.test-profile"
MONGODB_URI="mongodb+srv://administrator:[email protected]/mysite_development?retryWrites=true&w=majority"
INSERT_ENV_VAR () {
 if [[ -z "2ドル" ]]
 then
 echo "Failed to retrieve 1ドル"
 else
 if grep -q "1ドル" "$BASH_PROFILE"; then
 # Cannot use / delimiter, for value can contain /
 sed -in -E "s|(export 1ドル=)[a-zA-Z0-9@.:\/=&\-\?\+]+|1円2ドル|g" "$BASH_PROFILE"
 else
 echo "export 1ドル=2ドル" >> "$BASH_PROFILE"
 fi
 fi
}
INSERT_ENV_VAR 'ADMIN_EMAIL' '[email protected]'
INSERT_ENV_VAR 'MONGODB_URI' $MONGODB_URI

While the ADMIN_EMAIL variable is replaced fine, the MONGODB_URI variable is not being replaced. And I believe it has to do something with the character class [] inside of the regex. But I am not sure what. I tried it in a programming language like ruby and it found the match. But with sed it isn't finding the match. Why?

This is what I expect .test-profile to look like afterwards:

export [email protected]
export MONGODB_URI='mongodb+srv://administrator:[email protected]/mysite_development?retryWrites=true&w=majority'

Notice 'mysite_development' replaces 'test'.

• Paulo Tomé: The problem seems to be related with the ' character. Try your sed with (export MONGODB_URI=)[a-zA-Z0-9@.:\/=&\-\?\+']+ (adds a ' to the list of valid characters).
• Daniel Viglione: @PauloTomé adding ' seems to produce a result but not completely replacing old value with new value.
• NickD: You have unescaped & in the replacement string.
• NickD: Also why use such a complicated regex? Why not "s|(export 1ドル=).*|1円2ドル|"? And why use g? But you still have to escape & in 2ドル.
• NickD: I have - did you escape your ampersands?

Answer 1

Escaping the ampersand in the definition of MONGODB_URI in the script and simplifying the regex, getting rid of the -n and getting rid of the unnecessary g in the sed, we end up with this (the test profile is named differently in this version, but it should be clear what to do):

BASH_PROFILE="/tmp/test_profile"
MONGODB_URI="mongodb+srv://administrator:[email protected]/mysite_development?retryWrites=true\&w=majority"
INSERT_ENV_VAR () {
 if [[ -z "2ドル" ]]
 then
 echo "Failed to retrieve 1ドル"
 else
 if grep -q "1ドル" "$BASH_PROFILE"; then
 # Cannot use / delimiter, for value can contain /
 sed -i -E "s;(export 1ドル=).*;1円2ドル;" "$BASH_PROFILE"
 else
 echo "export 1ドル=2ドル" >> "$BASH_PROFILE"
 fi
 fi
}
INSERT_ENV_VAR 'ADMIN_EMAIL' '[email protected]'
INSERT_ENV_VAR 'MONGODB_URI' $MONGODB_URI

and running this with the test profile, I get:

export [email protected]
export MONGODB_URI=mongodb+srv://administrator:[email protected]/mysite_development?retryWrites=true&w=majority

• Daniel Viglione: Yes, I deleted the comment earlier because it did work.
• user391836: This will result in some inconsistency – when grep succeeds and sed is used the replacement made by sed won't contain a backslash before the &, but if the append-echo is used the `\` remains

Answer 2

sed -i "/export 1ドル=/{i export 1ドル='2ドル'
 ;d}" "$BASH_PROFILE"

This will allow you to use sed without needing to replace & with \&

• grep -q could have the options -F and also -m 1