Where do you set and access run-time configuration parameters per environment for service fabric?

In order to have per environment variables for running Service Fabric locally and in the cloud this is what you must do:

1. Add your custom config section and parameters to the Settings.xml file of the Service/Actor project (located at \PackageRoot\Config\Settings.xml from the project root). Leave the parameters blank as we will be setting these elsewhere per environment. Here is an example one.

<?xml version="1.0" encoding="utf-8" ?>
<Settings xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://schemas.microsoft.com/2011/01/fabric">
<!-- Add your custom configuration sections and parameters here -->
    <Section Name="UserDatabase">
        <Parameter Name="UserDatabaseConnectionString" Value="" />
    </Section>
</Settings>

2. In the ApplicationManifest.xml file of your Service Fabric project, there will be <ServiceManifestImport> elements for each of your included projects. Underneath that will be a <ConfigOverrides> element where we will declare what values for our configs will be supplanted by values set per environment in the local and cloud xml files underneath ApplicationParameters in our Service Fabric project. In that same ApplicationManifest.xml file, you’ll need to add the parameter that will be present in the local and cloud xml files, otherwise they’ll be overwritten upon build.

Continuing with the example above, this is how it would be set.

<Parameters>
    <Parameter Name="ServiceName_InstanceCount" DefaultValue="-1" />
    <Parameter Name="UserDatabaseConnectionString" DefaultValue="" />
</Parameters>
<ConfigOverrides>
    <ConfigOverride Name="Config">
        <Settings>
            <Section Name="UserDatabase">
                <Parameter Name="UserDatabaseConnectionString" Value="[UserDatabaseConnectionString]" />
            </Section>
        </Settings>
    </ConfigOverride>
</ConfigOverrides>

3. In the local.xml and cloud.xml files underneath ApplicationParameters in your Service Fabric project, you will specify your environment specific variables like so.

<?xml version="1.0" encoding="utf-8"?>
<Application xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" Name="fabric:/AppFabricName.ServiceFabric" xmlns="http://schemas.microsoft.com/2011/01/fabric">
    <Parameters>
        <Parameter Name="ServiceName_InstanceCount" Value="1" />
        <Parameter Name="UserDatabaseConnectionString" Value="Server=(localdb)\MsSqlLocalDb;Database=Users;User=ReadOnlyUser;Password=XXXXX;" />
    </Parameters>
</Application>

4. Finally, in your Service/Actor you can access these per-environment configuration variables like so.

var configurationPackage = Context.CodePackageActivationContext.GetConfigurationPackageObject("Config");

var connectionStringParameter = configurationPackage.Settings.Sections["UserDatabase"].Parameters["UserDatabaseConnectionString"];