[SOLVED] How to include variables in sed commands?

Issue

I have two different configuration files like following :

# Database
database.url=jdbc:mysql://127.0.0.1/database_name

and

# API
api.port=5005

I would like to change both of them, by utilizing sed commands in a shell script.

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What I have done & Problem :

This is the shell script that I made to accomplish it :

DB_CONFIG_FILE=~/configs/database.properties
MYSQL_CONTAINER_PORT=3113

sed -i 's~^database.url=jdbc:mysql://127.0.0.1/database_name.*database.url=jdbc:mysql://127.0.0.1:${MYSQL_CONTAINER_PORT}/database_name~' $DB_CONFIG_FILE

TM_CONFIG_FILE=~/configs/tm.properties
PORT=5100

sed -i 's~^api.port=5005.*api.port=${PORT}~' $TM_CONFIG_FILE

However, that gave me an error saying :

sed: -e expression #1, char : unterminated `s' command

Is there a workaround to include those variables declared in the script? Thank you

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Expectation :

My expectation is to modify the configuration files to something like this :

# Database
database.url=jdbc:mysql://127.0.0.1:3113/database_name

and

# API
api.port=5100

Solution

Few reasons:

1. Your sed command is broken as there is no substitution after delimiter ~
2. Shell variables won't expand in single quotes, use double quotes
3. RegEx meta characters such ., *. ?, + need to be escaped in sed regex.

Following sed should work for you:

dbCfgFile=~/configs/database.properties
mysqlContainerPort=3113
sed -E -i.bak "s~^(database\.url=jdbc:mysql://127\.0\.0\.1)(/.*)~\1:$mysqlContainerPort\2~" "$dbCfgFile"

Note that I am suggesting a regex with . escaped and using capture groups and back-references to avoid repeating same text in pattern and substitution.

Similarly for second sed use:

tmCfgFile=~/configs/tm.properties
port=5100
sed -E -i.bak "s/^(api\.port=).*/\1${port}/" "$tmCfgFile"

PS: I have renamed your shell variables from all caps to camel case to avoid clash with shell env variables.

Answered By - anubhava

Answer Checked By - Pedro (WPSolving Volunteer)