Find and replace a text in a XML file between two placeholders with a placeholder having special characters - sed

Question

I have a requirement mentioned below.
Sample file.txt ::
<?xml version='1.0' encoding='utf-8'?>
<Server port="${shutdown.port}" shutdown="SHUTDOWN">
<Listener className="org.apache.catalina.core.JasperListener" />
<Listener className="org.apache.catalina.core.JreMemoryLeakPreventionListener" />
<Listener className="org.apache.catalina.mbeans.ServerLifecycleListener" />
<Listener className="org.apache.catalina.mbeans.GlobalResourcesLifecycleListener" />
<Listener className="com.springsource.tcserver.serviceability.rmi.JmxSocketListener"
port="${jmx.port}"
bind="127.0.0.1"
useSSL="false"
passwordFile="${catalina.base}/conf/jmxremote.password"
accessFile="${catalina.base}/conf/jmxremote.access"
authenticate="true"/>
<Listener className="com.springsource.tcserver.serviceability.deploy.TcContainerDeployer" />
<GlobalNamingResources>
<Resource
name="jdbc/myDBPool1"
auth="Container"
type="oracle.jdbc.pool.OracleDataSource"
description="Oracle Datasource"
factory="oracle.jdbc.pool.OracleDataSourceFactory"
url="jdbc:oracle:thin:#localhost:<dbanme>"
user="myusername"
password="somepassword1"
validationQuery="SELECT 1 FROM DUAL"
/>
<Resource
name="jdbc/myDBPool2"
auth="Container"
type="oracle.jdbc.pool.OracleDataSource"
description="Oracle Datasource"
factory="oracle.jdbc.pool.OracleDataSourceFactory"
url="jdbc:oracle:thin:#localhost:<dbanme>"
user="myusername"
password="somepassword2"
validationQuery="SELECT 1 FROM DUAL"
/>
<Resource
name="jdbc/myDBPool3"
auth="Container"
type="oracle.jdbc.pool.OracleDataSource"
description="Oracle Datasource"
factory="oracle.jdbc.pool.OracleDataSourceFactory"
url="jdbc:oracle:thin:#localhost:<dbanme>"
user="myusername"
password="somepassword3"
validationQuery="SELECT 1 FROM DUAL"
/>
</GlobalNamingResources>
<Service name="Catalina">
<Executor name="tomcatThreadPool" namePrefix="tomcat-http--" maxThreads="300" minSpareThreads="50"/>
<Connector executor="tomcatThreadPool"
port="${http.port}"
protocol="HTTP/1.1"
connectionTimeout="20000"
redirectPort="${https.port}"
acceptCount="100"
maxKeepAliveRequests="15"/>
<Engine name="Catalina" defaultHost="localhost">
<!--
<Realm className="org.apache.catalina.realm.UserDatabaseRealm"
resourceName="UserDatabase"/>
-->
<Host name="localhost" appBase="webapps"
unpackWARs="true" autoDeploy="true" deployOnStartup="true" deployXML="true"
xmlValidation="false" xmlNamespaceAware="false">
</Host>
</Engine>
</Service>
</Server>
I am trying this script to find some text( .password. ) between two strings (inclusive of strings) and then replace it with a placeholder. Whenever my cmdlinepasswd placeholder has special characters say "/" character it fails.
sed -ie "/$datasource/,/password*/ {s/.*password.*/\tpassword=\"$cmdlinepasswd\"/;}" file.txt
assuming
datasource=jdbc/myDBPool1
cmdlinepasswd=new/passwd
I am new to scripting and any help would be appreciated.
Thank you.

Answer 1

This should do it:
awk -v RS= -v ORS='\n\n' -v datasource="jdbc/myDBPool1" -v cmdlinepasswd="new/passwd" '
$0 ~ "^[[:space:]]*<Resource.*name=\"" datasource "\"" {
sub(/password="[^"]+"/,"password=\"" cmdlinepasswd "\"")
} 1' file
It just looks for records that start with <Resource followed by name="<your datasource variable value>" and if it finds one it replaces the password in that record.
If you have shell variables already
datasource="jdbc/myDBPool1"
cmdlinepasswd="new/passwd"
just pass them into awk as:
awk -v RS= -v ORS='\n\n' -v datasource="$datasource" -v cmdlinepasswd="$cmdlinepasswd" '
$0 ~ "^[[:space:]]*<Resource.*name=\"" datasource "\"" {
sub(/password="[^"]+"/,"password=\"" cmdlinepasswd "\"")
} 1' file

Answer 2

One way using perl. It accepts three arguments, the variables to check/substitute and the input file. It's better than sed because it does quotemeta (\Q) to arguments, that escapes many special characters of a regex.
perl -pe '
## Get arguments but input file.
BEGIN { ($datasource,$cmdlinepasswd) = (shift,shift) }
## Get a range from resource name until the line with the password.
if ( $range = ( m/=\s*"\Q${datasource}"/ ... /password\s*=/ ) ) {
## "E0" points to last line (that contains the password, so
## change it.
if ( q|E0| eq substr $range, -2 ) {
s/(=\s*").*("\s*)$/$1${cmdlinepasswd}$2/;
}
}
' "$datasource" "$cmdlinepasswd" infile
With your example input data, it yields (only showed the part of the password that was modified, and left the rest untouched):
<?xml version='1.0' encoding='utf-8'?>
<Server port="${shutdown.port}" shutdown="SHUTDOWN">
<Listener className="org.apache.catalina.core.JasperListener" />
<Listener className="org.apache.catalina.core.JreMemoryLeakPreventionListener" />
<Listener className="org.apache.catalina.mbeans.ServerLifecycleListener" />
<Listener className="org.apache.catalina.mbeans.GlobalResourcesLifecycleListener" />
<Listener className="com.springsource.tcserver.serviceability.rmi.JmxSocketListener"
port="${jmx.port}"
bind="127.0.0.1"
useSSL="false"
passwordFile="${catalina.base}/conf/jmxremote.password"
accessFile="${catalina.base}/conf/jmxremote.access"
authenticate="true"/>
<Listener className="com.springsource.tcserver.serviceability.deploy.TcContainerDeployer" />
<GlobalNamingResources>
<Resource
name="jdbc/myDBPool1"
auth="Container"
type="oracle.jdbc.pool.OracleDataSource"
description="Oracle Datasource"
factory="oracle.jdbc.pool.OracleDataSourceFactory"
url="jdbc:oracle:thin:#localhost:<dbanme>"
user="myusername"
password="new/passwd"
validationQuery="SELECT 1 FROM DUAL"
/>
...
NOTE: After see your edit, it would be a better option to use an xml parser, but this solution seems to work in my test.