Octopus Web.config transforms for client endpoint address - web-config

Question

I have a web project that has uses two service endpoints located in the Web.config file under the client --> endpoint --> address portion
I have found the following per Octopus Variables section but cannot seem to find any reference of how to address the changes using and actual variable like you normally would
I am using the webui for Octopus which would be
http://{server-name}/app#/projects/{project-name}/variables
variable-substitution-syntax
I attempted assigning the variables like so, but the values never updated
the original entries look like the following
<endpoint address="http://services-test.example.com/test.svc/soap" binding="basicHttpBinding" bindingConfiguration="soap" contract="test.service" name="soap" />
Name Address Instance
Endpoint[A].Address test-service-a.example.com 1
Endpoint[B].Address test-service-b.example.com 2
Is this something that is ever possible using Octopus Variables? (I know it can be done using regular Web.config Transforms, as we are doing that already).
If it is possible what is would the correct replacement value for the
endpoint address
be and how would I accomplish this for multiple different endpoint addresses?

Answer 1

Sounds like you are most of the way there. If it's already working with your Web.config transforms then all you need to do is replace the value IN the transform with the variable replacement token.
For example: Web.Release.Config
<configuration xmlns:xdt="http://schemas.microsoft.com/XML-Document-Transform">
<system.serviceModel>
<client>
<endpoint address="http://#{Server1}/test.svc/soap" name="x1"
xdt:Locator="Match(name)" xdt:Transform="SetAttributes(address)" />
<endpoint address="#{Endpoint2}" name="x2"
xdt:Locator="Match(name)" xdt:Transform="SetAttributes(address)" />
</client>
</system.serviceModel>
</configuration>
Of course there are lots of options here.
For filenames you could stick with default conventions 'Web.Release.config' or go with 'Web.[Environment].config' or go with something custom. We use 'Web.Octopus.Config' so that it wont get picked up by any other process.
More on naming transforms here: https://octopus.com/docs/deploying-applications/configuration-files#Configurationfiles-Namingconfigurationtransformfiles
More on custom transforms (Web.Octopus.com) here: https://octopus.com/docs/deploying-applications/configuration-files#Configurationfiles-AdditionalConfigurationTransforms
For variables, you could define a variable for just the server (name=x1) which is simpler or just put the whole address in a variable with gives Octopus a lot more control (name=x2).
The key part is getting the variable replacement tokens into the config. Octopus runs the variable substitution on config files first, and then runs the transforms. What that means is the first pass will replace the tokens in your Web.Release.Config, and then Octopus will run the transforms against Web.config
Hope that helps.