FatAntelope

A tool for comparing two .config files and generating an XDT transform (Microsoft XML Document Transform). Useful for creating config transforms for existing production web.config or app.config files.

How it works

FatAntelope parses the two config (xml) files into two trees and performs an unordered diff / comparison to identify nodes that have been updated, inserted or deleted, and then generates a XDT transform from these differences.

The XML diff / comparison algorithm is a C# port of the 'XDiff' algorithm described here: http://pages.cs.wisc.edu/~yuanwang/xdiff.html

Try It

A demonstration is setup here: fatantelopetester-app.azurewebsites.net

Download

Download the command-line tool in releases

Usage

Following build, you can use reference the FatAntelope.Core library directly or otherwise run the command-line tool

Command Line Syntax

FatAntelope source-file target-file output-file [transformed-file]

   source-file : (input) original config file path.  E.g. the development web.config

   target-file : (input) final config file path.  E.g. the production web.config

   output-file : (output) file path to save the generated patch.  E.g. web.release.config

   transformed-file : (output, optional) file path to save the result from applying the output-file to the source-file.

Example

FatAntelope app.config prod_app.config app.release.config

Source File (app.config):

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <startup>
    <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5" />
  </startup>
  <connectionStrings>
    <add name="Users" connectionString="Data Source=127.0.0.1;initial catalog=UserDB;user id=myUser;password=myPassword" providerName="System.Data.EntityClient" />
    <add name="Posts" connectionString="Data Source=127.0.0.1;initial catalog=PostDB;user id=myUser;password=myPassword" providerName="System.Data.EntityClient" />
  </connectionStrings>
  <appSettings>
    <add key="MyUrl" value="http://localhost:50634" />
    <add key="MyService.Api" value="http://localhost:10424" />
  </appSettings>
</configuration>

Target File (prod_app.config) :

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <startup>
    <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5" />
  </startup>
  <connectionStrings>
    <add name="Users" connectionString="Data Source=203.1.1.1;initial catalog=UserDB;user id=myUser;password=myPassword" providerName="System.Data.EntityClient" />
    <add name="Posts" connectionString="Data Source=203.1.1.1;initial catalog=PostDB;user id=myUser;password=myPassword" providerName="System.Data.EntityClient" />
  </connectionStrings>
  <appSettings>
    <add key="MyUrl" value="http://MyAmazingWebsite.com" />
    <add key="MyService.Api" value="http://MyAmazingWebsite.com/Api" />
  </appSettings>
</configuration>

Patch File (app.release.config) :

<configuration xmlns:xdt="http://schemas.microsoft.com/XML-Document-Transform">
  <connectionStrings>
    <add name="Users" xdt:Locator="Match(name)" connectionString="Data Source=203.1.1.1;initial catalog=UserDB;user id=myUser;password=myPassword" xdt:Transform="SetAttributes(connectionString)" />
    <add name="Posts" xdt:Locator="Match(name)" connectionString="Data Source=203.1.1.1;initial catalog=PostDB;user id=myUser;password=myPassword" xdt:Transform="SetAttributes(connectionString)" />
  </connectionStrings>
  <appSettings>
    <add key="MyUrl" xdt:Locator="Match(key)" value="http://MyAmazingWebsite.com" xdt:Transform="SetAttributes(value)" />
    <add key="MyService.Api" xdt:Locator="Match(key)" value="http://MyAmazingWebsite.com/Api" xdt:Transform="SetAttributes(value)" />
  </appSettings>
</configuration>

Caveats

The generated XDT transform may not have the most optimal values for the xdt:Locator and xdt:Transform attributes. I recommend only using this output as a starting-point for your transforms.
The XML comparison algorithm used (XDiff) does an unordered comparison of XML nodes, so changes to child elements' position within the same parent will be ignored.

Why 'FatAntelope'

A fat antelope for a slow cheetah

CameronWills / FatAntelope

readme