[SOLVED] Update value in configuration file using shell script

TashiDuks · 11-16-2016, 08:08 PM

Hi Everyone,

I have an question on how to update value in configuration file using shell scripting.
I have following configuration file (info.conf):

Code:

"device.node_id": "server01",
"ftp.banner": "FTP server ready",
"ftp.enabled": false,
"ftp.port": 21

Now using the script I need to change the values.

Please someone suggest me.

Thanks

astrogeek · 11-16-2016, 09:44 PM

Welcome to LQ!

There are many choices for modifying character strings in a file, including sed, awk and shell built-in methods.

But you have not supplied enough information for anyone to offer much help.

Where will the new values come from?
How is the script intended to be used?
Should it change one value or multiple values?

Please try to rephrase your question in a more complete way, giving an example of how you want your script to work if possible.

See the Site FAQ for guidelines for asking more effective questions.

TashiDuks · 11-17-2016, 02:52 AM

Hi astrogeek,

Thanks for the information. Well to share further about my initial post.

I have info.conf file which is hidden and the info.conf contains following information:

Code:

"device.node_id": "server01",
"ftp.banner": "FTP server ready",
"ftp.enabled": false,
"ftp.port": 21

Now I want to have a shell script which will update the value of "device.node_id": to specified value. So to achieve that i have done the following script which works fine with only config file which is marked as executable.

Code:

#!/bin/bash

#Edit note name with double quotation e.g. "webserver01".
newNode="server211"

#Set OpenCanary Configuration File Path
openCanaryConfig="info.conf"
sed -i 's/\(^"device.node_id":\).*/\1 "'$newNode'",/' $openCanaryConfig

After running the above script my info.conf file changes to:

Code:

"device.node_id": "server211",
"ftp.banner": "FTP server ready",
"ftp.enabled": false,
"ftp.port": 21

But how to do with configuration file which is marked as executable (like info.conf*)

Info: when i run ll in terminal, i see * being marked at the end of info.conf file.

Can you please suggest, hope i have missed a option.

Thanks

grail · 11-17-2016, 06:44 AM

The permissions are not really an issue unless you did not have access to the file. Having it executable will make no difference to your script. The asterisk you see when using ls -l is simply there
to identify the file as executable but is no part of the file name. To confirm try the following in the same directory:

Code:

\ls -l

astrogeek · 11-18-2016, 04:19 AM

As grail points out, the * appears only as an indicaator in file listings and does not affect the file name or your ability to update it.

If your script fails to update the file, please post here the output of ls -l for the config file, and tell us the user name running the script. It is probably due to the user not having permission to update the file.

TashiDuks · 12-02-2016, 02:12 AM

Hi,

I finally managed to solve this issue. I used following parameter for my 'sed':

Code:

sed -i 's/\("device.node_id":\).*/\1 "'$newNode'",/' $openCanaryConfig

Thanks