From 58426426430b7ba2955a72014a0074791d1f7a4e Mon Sep 17 00:00:00 2001
From: Joe Topjian <joe@topjian.net>
Date: Tue, 16 May 2017 02:36:50 -0600
Subject: [PATCH] provider/openstack: Handle Deleted Resources in Floating IP
 Association (#14533)

This commit modifies the openstack_compute_floatingip_associate_v2 resource
to handle cases where the floating IP or instance were deleted outside of
Terraform.
---
 ...enstack_compute_floatingip_associate_v2.go | 104 ++++++++++++++++++
 1 file changed, 104 insertions(+)

diff --git a/builtin/providers/openstack/resource_openstack_compute_floatingip_associate_v2.go b/builtin/providers/openstack/resource_openstack_compute_floatingip_associate_v2.go
index c2e1d6888..963e191d6 100644
--- a/builtin/providers/openstack/resource_openstack_compute_floatingip_associate_v2.go
+++ b/builtin/providers/openstack/resource_openstack_compute_floatingip_associate_v2.go
@@ -5,7 +5,10 @@ import (
 	"log"
 	"strings"
 
+	"github.com/gophercloud/gophercloud"
 	"github.com/gophercloud/gophercloud/openstack/compute/v2/extensions/floatingips"
+	"github.com/gophercloud/gophercloud/openstack/compute/v2/servers"
+	nfloatingips "github.com/gophercloud/gophercloud/openstack/networking/v2/extensions/layer3/floatingips"
 	"github.com/hashicorp/terraform/helper/schema"
 )
 
@@ -79,12 +82,67 @@ func resourceComputeFloatingIPAssociateV2Create(d *schema.ResourceData, meta int
 }
 
 func resourceComputeFloatingIPAssociateV2Read(d *schema.ResourceData, meta interface{}) error {
+	config := meta.(*Config)
+	computeClient, err := config.computeV2Client(GetRegion(d))
+	if err != nil {
+		return fmt.Errorf("Error creating OpenStack compute client: %s", err)
+	}
+
 	// Obtain relevant info from parsing the ID
 	floatingIP, instanceId, fixedIP, err := parseComputeFloatingIPAssociateId(d.Id())
 	if err != nil {
 		return err
 	}
 
+	// Now check and see whether the floating IP still exists.
+	// First try to do this by querying the Network API.
+	networkEnabled := true
+	networkClient, err := config.networkingV2Client(GetRegion(d))
+	if err != nil {
+		networkEnabled = false
+	}
+
+	var exists bool
+	if networkEnabled {
+		log.Printf("[DEBUG] Checking for Floating IP existence via Network API")
+		exists, err = resourceComputeFloatingIPAssociateV2NetworkExists(networkClient, floatingIP)
+	} else {
+		log.Printf("[DEBUG] Checking for Floating IP existence via Compute API")
+		exists, err = resourceComputeFloatingIPAssociateV2ComputeExists(computeClient, floatingIP)
+	}
+
+	if err != nil {
+		return err
+	}
+
+	if !exists {
+		d.SetId("")
+	}
+
+	// Next, see if the instance still exists
+	instance, err := servers.Get(computeClient, instanceId).Extract()
+	if err != nil {
+		if CheckDeleted(d, err, "instance") == nil {
+			return nil
+		}
+	}
+
+	// Finally, check and see if the floating ip is still associated with the instance.
+	var associated bool
+	for _, networkAddresses := range instance.Addresses {
+		for _, element := range networkAddresses.([]interface{}) {
+			address := element.(map[string]interface{})
+			if address["OS-EXT-IPS:type"] == "floating" && address["addr"] == floatingIP {
+				associated = true
+			}
+		}
+	}
+
+	if !associated {
+		d.SetId("")
+	}
+
+	// Set the attributes pulled from the composed resource ID
 	d.Set("floating_ip", floatingIP)
 	d.Set("instance_id", instanceId)
 	d.Set("fixed_ip", fixedIP)
@@ -128,3 +186,49 @@ func parseComputeFloatingIPAssociateId(id string) (string, string, string, error
 
 	return floatingIP, instanceId, fixedIP, nil
 }
+
+func resourceComputeFloatingIPAssociateV2NetworkExists(networkClient *gophercloud.ServiceClient, floatingIP string) (bool, error) {
+	listOpts := nfloatingips.ListOpts{
+		FloatingIP: floatingIP,
+	}
+	allPages, err := nfloatingips.List(networkClient, listOpts).AllPages()
+	if err != nil {
+		return false, err
+	}
+
+	allFips, err := nfloatingips.ExtractFloatingIPs(allPages)
+	if err != nil {
+		return false, err
+	}
+
+	if len(allFips) > 1 {
+		return false, fmt.Errorf("There was a problem retrieving the floating IP")
+	}
+
+	if len(allFips) == 0 {
+		return false, nil
+	}
+
+	return true, nil
+}
+
+func resourceComputeFloatingIPAssociateV2ComputeExists(computeClient *gophercloud.ServiceClient, floatingIP string) (bool, error) {
+	// If the Network API isn't available, fall back to the deprecated Compute API.
+	allPages, err := floatingips.List(computeClient).AllPages()
+	if err != nil {
+		return false, err
+	}
+
+	allFips, err := floatingips.ExtractFloatingIPs(allPages)
+	if err != nil {
+		return false, err
+	}
+
+	for _, f := range allFips {
+		if f.IP == floatingIP {
+			return true, nil
+		}
+	}
+
+	return false, nil
+}