API Management - Set Backend Service as Operation Policy in Terraform

Question

I'm creating an APIM in Azure using Terraform. So far I've been able to create the APIM instance, the API and an operation within the API. Because I want each operation for the API to point to an individual Logic App, my understanding is I cannot set this as an azurerm_api_management_backend and instead need to set it in the operation policy in XML.

This is what my operation policy looks like:

resource "azurerm_api_management_api_operation_policy" "apim1_ss_cmpcomplaints_api_dev_get_policy" {
  api_name            = azurerm_api_management_api.apim1_ss_api_dev.name
  api_management_name = azurerm_api_management.test-apimManagement.name
  resource_group_name = azurerm_resource_group.apimResourceGroup.name
  operation_id        = "get-complaints"
  xml_content         = <<XML
  <policies>
    <inbound>
        <base />
        <set-method id="apim-generated-policy">GET</set-method>
        <set-backend-service id="apim-generated-policy" backend-id="/subscriptions/xxx/resourceGroups/hm-iac-msdn-neu-rg/providers/Microsoft.Logic/workflows/testLogicApp" />
    </inbound>
    <backend>
        <base />
    </backend>
    <outbound>
        <base />
    </outbound>
    <on-error>
        <base />
    </on-error>
  </policies>
  XML
}

I have created the Logic App and retrieved the resource ID from the Azure CLI and included it in the set-backend-service node. But despite getting the ID from the CLI, I am getting the following response:

│ Error: creating or updating API Operation Policy (Resource Group "apim-resource-group" / API Management Service "harry-test-apim" / API "test_api_dev" / Operation "get-complaints"): apimanagement.APIOperationPolicyClient#CreateOrUpdate: Failure responding to request: StatusCode=400 -- Original Error: autorest/azure: Service returned an error. Status=400 Code="ValidationError" Message="One or more fields contain incorrect values:" Details=[{"code":"ValidationError","message":"Error in element 'set-backend-service' on line 5, column 10: Backend with id '/subscriptions/xxx/resourceGroups/hm-iac-msdn-neu-rg/providers/Microsoft.Logic/workflows/testLogicApp' could not be found.","target":"set-backend-service"}]

I'd prefer to set this using the resource ID instead of using base-url.

score 0 · Answer 1 · answered Apr 06 '23 at 08:47

It's possible.

I'm using the following

resource "azurerm_api_management_backend" "backend_1" {
  name                = "backend-${var.project_name}-${var.environment}-ert45"
  resource_group_name = azurerm_resource_group.rg_app.name
  api_management_name = azurerm_api_management.apim.name

  protocol = "http"
  url      = "yoururl"
}

resource "azurerm_api_management_api_policy" "api_1_policy" {
  api_name            = azurerm_api_management_api.api_1.name
  resource_group_name = azurerm_resource_group.rg_app.name
  api_management_name = azurerm_api_management.apim.name

  xml_content = <<XML
<policies>
  <inbound>
     <base />
     <set-backend-service backend-id="${azurerm_api_management_backend.backend_1.name}" />

  </inbound>
  <backend>
      <base />
  </backend>
  <outbound>
      <base />
  </outbound>
  <on-error>
      <base />
  </on-error>
</policies>
XML

  depends_on = [
    azurerm_api_management_backend.backend_1,
    azurerm_api_management_api.api_1
  ]
}

score -1 · Accepted Answer · answered Dec 01 '21 at 14:26

-1

The backend-id is different to the ARM id. It's not easy to find, so the solution is to generate the policy in the APIM front-end and then apply that in code afterwards.

answered Dec 01 '21 at 14:26

HarryMoy

142
3
20

Your answer could be improved with additional supporting information. Please [edit] to add further details, such as citations or documentation, so that others can confirm that your answer is correct. You can find more information on how to write good answers [in the help center](/help/how-to-answer). – Community Dec 01 '21 at 15:18

API Management - Set Backend Service as Operation Policy in Terraform

2 Answers2