xmlpoke in Nant - how to update all instances of found string

Question

Hi I am using Xpath in my Nant build script to change some config variables between development and my other environments.

I have taken the syntax from this example:

The example looks like this:

<xmlpoke
    file="config01/app.config"
    xpath="/configuration/appSettings/add[@key='AppName']/@value"
    value="TradeMonster">
</xmlpoke>

What I would like is something similar to this to search my connection strings and find all instances of "localhost\SqlExpress" and just change them to just "localhost"

Is this possible?

Answer 1

Toying with a quick'n dirty script here....

If you're sure there is only one connectionstring element in each file you can accomplish this with a combination of xmlpeek and xmlpoke. Modifying the string is easier done with some C#, therefore using a script task to do a regex search and replace:

 <script language="C#" prefix="custom" >
      <code>
        <![CDATA[
          [Function("fix")]
          public static string Fix(string input) {
              return Regex.Replace(input, @"localhost\\\w+", "localhost");
          }
        ]]>
      </code>
  </script>

<!-- Get the existing connection string -->
<xmlpeek
    file="config01/app.config"
    xpath="/configuration/connectionStrings/add[@contains(@connectionString,'localhost\')]/@connectionString"
    property="connectionstring">
</xmlpeek>

<!-- Write back the modified connection string -->
<xmlpoke
    file="config01/app.config"
    xpath="/configuration/connectionStrings/add[@contains(@connectionString,'localhost\')]/@connectionString"
    value="${custom::fix(connectionstring)}">
</xmlpoke>

Answer 2

XPath only selects nodes, it cannot change nodes.

One way to accomplish the needed changes is to perform an XSLT transformation on the XML document.

In order to make this happen, you have to provide the XML document and to specify exactly which of its text nodes are to be changed.