Terraform Error: Failed to query available provider packages

I'm trying to deploy a simple infrastructure in Azure through Terraform, the infrastructure is made of an Application Gateway (with Web Application Firewall, so the WAF_v2 version) with two virtual machines in the backend. At the beginning I have implemented the Application Gateway (Standard_v2) without the WAF, and worked properly, but when I have implemented the WAF, I got the following error after lunching "terraform init" command (see attached screenshot also):

Error: Failed to query available provider packages
│
│ Could not retrieve the list of available versions for provider hashicorp/example: provider registry registry.terraform.io does not have a provider named
│ registry.terraform.io/hashicorp/example
│
│ All modules should specify their required_providers so that external consumers will get the correct providers when using a module. To see which modules are currently depending
│ on hashicorp/example, run the following command:
│     terraform providers

So I run the command "terraform providers" as suggested by Terraform and got this:

Providers required by configuration:
.
├── provider[registry.terraform.io/hashicorp/azurerm] >= 2.97.0
├── provider[registry.terraform.io/hashicorp/example]
└── provider[registry.terraform.io/hashicorp/random]

In the following you can see the Terraform code of my infrastructure:

terraform {

  required_version = ">=0.12"

  required_providers {
    azurerm = {
      source  = "hashicorp/azurerm"
      version = ">=2.97.0"
    }
  }
}

provider "azurerm" {
  features {}
}

resource "azurerm_resource_group" "rg1" {
  name     = "myResourceGroupAG"
  location = "francecentral"
}

resource "example_wafpolicy" "exampleWAF" {
  name                = "example_wafpolicy_name"
  resource_group_name = azurerm_resource_group.rg1.name
  location            = azurerm_resource_group.rg1.location

  custom_rules {
    name      = "Rule1"
    priority  = 1
    rule_type = "MatchRule"

    match_conditions {
      match_variables {
        variable_name = "RemoteAddr"
      }

      operator           = "IPMatch"
      negation_condition = false
      match_values       = ["XX.XX.XX.XX"]
    }

    action = "Block"
  }


  policy_settings {
    enabled                     = true
    mode                        = "Prevention"
    request_body_check          = true
    file_upload_limit_in_mb     = 100
    max_request_body_size_in_kb = 128
  }

  managed_rules {
    managed_rule_set {
      type    = "OWASP"
      version = "3.2"
    }
  }
}

resource "azurerm_virtual_network" "vnet1" {
  name                = "myVNet"
  resource_group_name = azurerm_resource_group.rg1.name
  location            = azurerm_resource_group.rg1.location
  address_space       = ["10.21.0.0/16"]
}

resource "azurerm_subnet" "frontend" {
  name                 = "myAGSubnet"
  resource_group_name  = azurerm_resource_group.rg1.name
  virtual_network_name = azurerm_virtual_network.vnet1.name
  address_prefixes     = ["10.21.0.0/24"]
}

resource "azurerm_subnet" "backend" {
  name                 = "myBackendSubnet"
  resource_group_name  = azurerm_resource_group.rg1.name
  virtual_network_name = azurerm_virtual_network.vnet1.name
  address_prefixes     = ["10.21.1.0/24"]
}

resource "azurerm_public_ip" "pip1" {
  name                = "myAGPublicIPAddress"
  resource_group_name = azurerm_resource_group.rg1.name
  location            = azurerm_resource_group.rg1.location
  allocation_method   = "Static"
  sku                 = "Standard"
}



resource "azurerm_application_gateway" "network" {
  name                = "myAppGateway"
  resource_group_name = azurerm_resource_group.rg1.name
  location            = azurerm_resource_group.rg1.location

  sku {
    name     = "WAF_v2"
    tier     = "WAF_v2"
    capacity = 2
  }

  gateway_ip_configuration {
    name      = "my-gateway-ip-configuration"
    subnet_id = azurerm_subnet.frontend.id
  }

  frontend_port {
    name = var.frontend_port_name
    port = 80
  }

  frontend_ip_configuration {
    name                 = var.frontend_ip_configuration_name
    public_ip_address_id = azurerm_public_ip.pip1.id
  }

  backend_address_pool {
    name = var.backend_address_pool_name
  }

  backend_http_settings {
    name                  = var.http_setting_name
    cookie_based_affinity = "Disabled"
    port                  = 80
    protocol              = "Http"
    request_timeout       = 20
  }

  http_listener {
    name                           = var.listener_name
    frontend_ip_configuration_name = var.frontend_ip_configuration_name
    frontend_port_name             = var.frontend_port_name
    protocol                       = "Http"
    firewall_policy_id             =  example_wafpolicy.exampleWAF.id
  }

  request_routing_rule {
    name                       = var.request_routing_rule_name
    rule_type                  = "Basic"
    priority                   = 25
    http_listener_name         = var.listener_name
    backend_address_pool_name  = var.backend_address_pool_name
    backend_http_settings_name = var.http_setting_name
  }

  firewall_policy_id {
    id             =  example_wafpolicy.exampleWAF.id
  }

  waf_configuration  {
    content{
          enabled                  = lookup(waf_configuration.value,"enabled",true)
          file_upload_limit_mb     = lookup(waf_configuration.value,"file_upload_limit_mb",30)
          firewall_mode            = lookup(waf_configuration.value,"firewall_mode","Prevention")
          max_request_body_size_kb = lookup(waf_configuration.value,"max_request_body_size_kb",128)
          request_body_check       = lookup(waf_configuration.value,"request_body_check",true)
          rule_set_type            = lookup(waf_configuration.value,"rule_set_type","OWASP")
          rule_set_version         = lookup(waf_configuration.value,"rule_set_version", "3.1")
    }
  }


}



resource "azurerm_network_interface" "nic" {
  count = 2
  name                = "nic-${count.index+1}"
  location            = azurerm_resource_group.rg1.location
  resource_group_name = azurerm_resource_group.rg1.name

  ip_configuration {
    name                          = "nic-ipconfig-${count.index+1}"
    subnet_id                     = azurerm_subnet.backend.id
    private_ip_address_allocation = "Dynamic"
  }
}

resource "azurerm_network_interface_application_gateway_backend_address_pool_association" "nic-assoc01" {
  count = 2
  network_interface_id    = azurerm_network_interface.nic[count.index].id
  ip_configuration_name   = "nic-ipconfig-${count.index+1}"
  backend_address_pool_id = tolist(azurerm_application_gateway.network.backend_address_pool).0.id
}

resource "random_password" "password" {
  length = 16
  special = true
  lower = true
  upper = true
  numeric = true
}

resource "azurerm_windows_virtual_machine" "vm" {
  count = 2
  name                = "myVM${count.index+1}"
  resource_group_name = azurerm_resource_group.rg1.name
  location            = azurerm_resource_group.rg1.location
  size                = "Standard_DS1_v2"
  admin_username      = "azureadmin"
  admin_password      = random_password.password.result

  network_interface_ids = [
    azurerm_network_interface.nic[count.index].id,
  ]

  os_disk {
    caching              = "ReadWrite"
    storage_account_type = "Standard_LRS"
  }


  source_image_reference {
    publisher = "MicrosoftWindowsServer"
    offer     = "WindowsServer"
    sku       = "2019-Datacenter"
    version   = "latest"
  }
}

resource "azurerm_virtual_machine_extension" "vm-extensions" {
  count = 2
  name                 = "vm${count.index+1}-ext"
  virtual_machine_id   = azurerm_windows_virtual_machine.vm[count.index].id
  publisher            = "Microsoft.Compute"
  type                 = "CustomScriptExtension"
  type_handler_version = "1.10"

  settings = <<SETTINGS
    {
        "commandToExecute": "powershell Add-WindowsFeature Web-Server; powershell Add-Content -Path \"C:\\inetpub\\wwwroot\\Default.htm\" -Value $($env:computername)"
    }
SETTINGS

}

In the following the script with the variables:

variable "backend_address_pool_name" {
  default = "myBackendPool"
}

variable "frontend_port_name" {
  default = "myFrontendPort"
}

variable "frontend_ip_configuration_name" {
  default = "myAGIPConfig"
}

variable "http_setting_name" {
  default = "myHTTPsetting"
}

variable "listener_name" {
  default = "myListener"
}

variable "request_routing_rule_name" {
  default = "myRoutingRule"
}

variable "redirect_configuration_name" {
  default = "myRedirectConfig"
}

variable "example_wafpolicy_name" {
  default = "myFirewallPolicy"
}

At the beginning of the code you can see match_values = ["XX.XX.XX.XX"], the IP address is set in this manner just for opening this question in Stackoverflow, normally in my code there is a normal IP address. I would really appreciate your help to fix this error and in general to deploy an Application Gateway with WAF and two virtual machines in the backend in Azure through Terraform.

I have tried to search something online but it seems that this topic has never been opened by someone.

Issue was caused because of the naming convention which used in terraform code base "example_wafpolicy" and terraform provider.

Solution: Need to replace with below mention resource tag

resource "azurerm_web_application_firewall_policy" "example" {

Replicated the same code base in local, please find below code snippet.

Main if file as follows:

resource "azurerm_resource_group" "rg1" {
  name     = "************"
  location = "West Europe"
}
resource "azurerm_web_application_firewall_policy" "exampleWAF" {
  name                = "example_wafpolicy_name"
  resource_group_name = azurerm_resource_group.rg1.name
  location            = azurerm_resource_group.rg1.location

  custom_rules {
    name      = "Rule1"
    priority  = 1
    rule_type = "MatchRule"

    match_conditions {
      match_variables {
        variable_name = "RemoteAddr"
      }

      operator           = "IPMatch"
      negation_condition = false
      match_values       =  ["192.168.1.0/24", "10.0.0.0/24"]
    }

    action = "Block"
  }


  policy_settings {
    enabled                     = true
    mode                        = "Prevention"
    request_body_check          = true
    file_upload_limit_in_mb     = 100
    max_request_body_size_in_kb = 128
  }

  managed_rules {
    managed_rule_set {
      type    = "OWASP"
      version = "3.2"
    }
  }
}

resource "azurerm_virtual_network" "vnet1" {
  name                = "myVNet"
  resource_group_name = azurerm_resource_group.rg1.name
  location            = azurerm_resource_group.rg1.location
  address_space       = ["10.21.0.0/16"]
}

resource "azurerm_subnet" "frontend" {
  name                 = "myAGSubnet"
  resource_group_name  = azurerm_resource_group.rg1.name
  virtual_network_name = azurerm_virtual_network.vnet1.name
  address_prefixes     = ["10.21.0.0/24"]
}

resource "azurerm_subnet" "backend" {
  name                 = "myBackendSubnet"
  resource_group_name  = azurerm_resource_group.rg1.name
  virtual_network_name = azurerm_virtual_network.vnet1.name
  address_prefixes     = ["10.21.1.0/24"]
}

resource "azurerm_public_ip" "pip1" {
  name                = "myAGPublicIPAddress"
  resource_group_name = azurerm_resource_group.rg1.name
  location            = azurerm_resource_group.rg1.location
  allocation_method   = "Dynamic"
  sku                 = "Basic"
}

locals {
  backend_address_pool_name      = "${azurerm_virtual_network.vnet1.name}-beap"
  frontend_port_name             = "${azurerm_virtual_network.vnet1.name}-feport"
  frontend_ip_configuration_name = "${azurerm_virtual_network.vnet1.name}-feip"
  http_setting_name              = "${azurerm_virtual_network.vnet1.name}-be-htst"
  listener_name                  = "${azurerm_virtual_network.vnet1.name}-httplstn"
  request_routing_rule_name      = "${azurerm_virtual_network.vnet1.name}-rqrt"
  redirect_configuration_name    = "${azurerm_virtual_network.vnet1.name}-rdrcfg"
}

resource "azurerm_application_gateway" "network" {
  name                = "example-appgateway"
  resource_group_name = azurerm_resource_group.rg1.name
  location            = azurerm_resource_group.rg1.location

  sku {
    name     = "Standard_Small"
    tier     = "Standard"
    capacity = 2
  }

  gateway_ip_configuration {
    name      = "my-gateway-ip-configuration"
    subnet_id = azurerm_subnet.frontend.id
  }

  frontend_port {
    name = local.frontend_port_name
    port = 80
  }

  frontend_ip_configuration {
    name                 = local.frontend_ip_configuration_name
    public_ip_address_id = azurerm_public_ip.pip1.id
  }

  backend_address_pool {
    name = local.backend_address_pool_name
  }

  backend_http_settings {
    name                  = local.http_setting_name
    cookie_based_affinity = "Disabled"
    path                  = "/path1/"
    port                  = 80
    protocol              = "Http"
    request_timeout       = 60
  }

  http_listener {
    name                           = local.listener_name
    frontend_ip_configuration_name = local.frontend_ip_configuration_name
    frontend_port_name             = local.frontend_port_name
    protocol                       = "Http"
  }

  request_routing_rule {
    name                       = local.request_routing_rule_name
    rule_type                  = "Basic"
    http_listener_name         = local.listener_name
    backend_address_pool_name  = local.backend_address_pool_name
    backend_http_settings_name = local.http_setting_name
  }
}
resource "azurerm_network_interface" "nic" {
  count = 2
  name                = "nic-${count.index+1}"
  location            = azurerm_resource_group.rg1.location
  resource_group_name = azurerm_resource_group.rg1.name

  ip_configuration {
    name                          = "nic-ipconfig-${count.index+1}"
    subnet_id                     = azurerm_subnet.backend.id
    private_ip_address_allocation = "Dynamic"
  }
}

resource "azurerm_network_interface_application_gateway_backend_address_pool_association" "nic-assoc01" {
  count = 2
  network_interface_id    = azurerm_network_interface.nic[count.index].id
  ip_configuration_name   = "nic-ipconfig-${count.index+1}"
  backend_address_pool_id = tolist(azurerm_application_gateway.network.backend_address_pool).0.id
}

resource "random_password" "password" {
  length = 16
  special = true
  lower = true
  upper = true
  numeric = true
}

resource "azurerm_windows_virtual_machine" "vm" {
  count = 2
  name                = "myVM${count.index+1}"
  resource_group_name = azurerm_resource_group.rg1.name
  location            = azurerm_resource_group.rg1.location
  size                = "Standard_DS1_v2"
  admin_username      = "azureadmin"
  admin_password      = random_password.password.result

  network_interface_ids = [
    azurerm_network_interface.nic[count.index].id,
  ]

  os_disk {
    caching              = "ReadWrite"
    storage_account_type = "Standard_LRS"
  }


  source_image_reference {
    publisher = "MicrosoftWindowsServer"
    offer     = "WindowsServer"
    sku       = "2019-Datacenter"
    version   = "latest"
  }
}

resource "azurerm_virtual_machine_extension" "vm-extensions" {
  count = 2
  name                 = "vm${count.index+1}-ext"
  virtual_machine_id   = azurerm_windows_virtual_machine.vm[count.index].id
  publisher            = "Microsoft.Compute"
  type                 = "CustomScriptExtension"
  type_handler_version = "1.10"

  settings = <<SETTINGS
    {
        "commandToExecute": "powershell Add-WindowsFeature Web-Server; powershell Add-Content -Path \"C:\\inetpub\\wwwroot\\Default.htm\" -Value $($env:computername)"
    }
SETTINGS

}

provider tf file as follows:

terraform {
  
      required_version = "~>1.3.3"
      required_providers {
        azurerm = {
           source = "hashicorp/azurerm"
           version = ">=3.0.0"
             }
           }
 }

 provider "azurerm" {
    features {}
    skip_provider_registration = true
}

upon running terraform plan and apply

terraform plan
terraform apply -auto-approve

Plan as follows:

Apply as follows

Azure Portal verification: