Fix container ports issue for asc ordering (#115)

* Attempts to fix container ports issue by converting list to a set.
* Revert "Attempts to fix container ports issue by converting list to a set." This reverts commit 5660759875ca65e2b8c5b9aa8b25cc3ff7eee2d9.
* adds migration state func for container. Suppresses diff for port migration
* Updates changelog for v1.1.1

CHANGELOG.md

@@ -1,5 +1,10 @@
 ## 1.1.1 (Unreleased)
 
+BUG FIXES
+* Fixes no more 'force new resource' for container ports when
+there are no changes. This was caused to the ascending order. See [GH-110] 
+for details and [[#115](https://github.com/terraform-providers/terraform-provider-docker/pull/115)]
+
 DOCS
 * Corrects `networks_advanced` section [GH-109]
 * Corrects `tmpfs_options` section [GH-122]

docker/resource_docker_container.go

@@ -1,15 +1,19 @@
 package docker
 
 import (
+	"log"
+
 	"github.com/hashicorp/terraform/helper/schema"
 )
 
 func resourceDockerContainer() *schema.Resource {
 	return &schema.Resource{
-		Create: resourceDockerContainerCreate,
+		Create:        resourceDockerContainerCreate,
-		Read:   resourceDockerContainerRead,
+		Read:          resourceDockerContainerRead,
-		Update: resourceDockerContainerUpdate,
+		Update:        resourceDockerContainerUpdate,
-		Delete: resourceDockerContainerDelete,
+		Delete:        resourceDockerContainerDelete,
+		MigrateState:  resourceDockerContainerMigrateState,
+		SchemaVersion: 1,
 
 		Schema: map[string]*schema.Schema{
 			"name": &schema.Schema{
@@ -259,6 +263,7 @@ func resourceDockerContainer() *schema.Resource {
 						},
 					},
 				},
+				DiffSuppressFunc: suppressIfPortsDidNotChangeForMigrationV0ToV1(),
 			},
 
 			"host": &schema.Schema{
@@ -601,3 +606,49 @@ func resourceDockerContainer() *schema.Resource {
 		},
 	}
 }
+
+func suppressIfPortsDidNotChangeForMigrationV0ToV1() schema.SchemaDiffSuppressFunc {
+	return func(k, old, new string, d *schema.ResourceData) bool {
+		portsOldRaw, portsNewRaw := d.GetChange("ports")
+		portsOld := portsOldRaw.([]interface{})
+		portsNew := portsNewRaw.([]interface{})
+		if len(portsOld) != len(portsNew) {
+			log.Printf("[DEBUG] suppress diff ports: old and new don't have the same length")
+			return false
+		}
+		log.Printf("[DEBUG] suppress diff ports: old and new have same length")
+
+		for _, portOld := range portsOld {
+			portOldMapped := portOld.(map[string]interface{})
+			oldInternalPort := portOldMapped["internal"]
+			portFound := false
+			for _, portNew := range portsNew {
+				portNewMapped := portNew.(map[string]interface{})
+				newInternalPort := portNewMapped["internal"]
+				// port is still there in new
+				if newInternalPort == oldInternalPort {
+					log.Printf("[DEBUG] suppress diff ports: comparing port '%v'", oldInternalPort)
+					portFound = true
+					if portNewMapped["external"] != portOldMapped["external"] {
+						log.Printf("[DEBUG] suppress diff ports: 'external' changed for '%v'", oldInternalPort)
+						return false
+					}
+					if portNewMapped["ip"] != portOldMapped["ip"] {
+						log.Printf("[DEBUG] suppress diff ports: 'ip' changed for '%v'", oldInternalPort)
+						return false
+					}
+					if portNewMapped["protocol"] != portOldMapped["protocol"] {
+						log.Printf("[DEBUG] suppress diff ports: 'protocol' changed for '%v'", oldInternalPort)
+						return false
+					}
+				}
+			}
+			// port was deleted or exchanges in new
+			if !portFound {
+				log.Printf("[DEBUG] suppress diff ports: port was deleted '%v'", oldInternalPort)
+				return false
+			}
+		}
+		return true
+	}
+}

docker/resource_docker_container_migrate.go

@@ -0,0 +1,115 @@
+package docker
+
+import (
+	"fmt"
+	"log"
+	"sort"
+
+	"github.com/hashicorp/terraform/helper/schema"
+	"github.com/hashicorp/terraform/terraform"
+)
+
+func resourceDockerContainerMigrateState(
+	v int, is *terraform.InstanceState, meta interface{}) (*terraform.InstanceState, error) {
+	switch v {
+	case 0:
+		log.Println("[INFO] Found Docker Container State v0; migrating to v1")
+		return migrateDockerContainerMigrateStateV0toV1(is, meta)
+	default:
+		return is, fmt.Errorf("Unexpected schema version: %d", v)
+	}
+}
+
+func migrateDockerContainerMigrateStateV0toV1(is *terraform.InstanceState, meta interface{}) (*terraform.InstanceState, error) {
+	if is.Empty() {
+		log.Println("[DEBUG] Empty InstanceState; nothing to migrate.")
+		return is, nil
+	}
+
+	log.Printf("[DEBUG] Docker Container Attributes before Migration: %#v", is.Attributes)
+
+	err := updateV0ToV1PortsOrder(is, meta)
+
+	log.Printf("[DEBUG] Docker Container Attributes after State Migration: %#v", is.Attributes)
+
+	return is, err
+}
+
+type mappedPort struct {
+	internal int
+	external int
+	ip       string
+	protocol string
+}
+
+type byPort []mappedPort
+
+func (s byPort) Len() int {
+	return len(s)
+}
+func (s byPort) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+func (s byPort) Less(i, j int) bool {
+	return s[i].internal < s[j].internal
+}
+
+func updateV0ToV1PortsOrder(is *terraform.InstanceState, meta interface{}) error {
+	reader := &schema.MapFieldReader{
+		Schema: resourceDockerContainer().Schema,
+		Map:    schema.BasicMapReader(is.Attributes),
+	}
+
+	writer := &schema.MapFieldWriter{
+		Schema: resourceDockerContainer().Schema,
+	}
+
+	result, err := reader.ReadField([]string{"ports"})
+	if err != nil {
+		return err
+	}
+
+	if result.Value == nil {
+		return nil
+	}
+
+	// map the ports into a struct, so they can be sorted easily
+	portsMapped := make([]mappedPort, 0)
+	portsRaw := result.Value.([]interface{})
+	for _, portRaw := range portsRaw {
+		if portRaw == nil {
+			continue
+		}
+		portTyped := portRaw.(map[string]interface{})
+		portMapped := mappedPort{
+			internal: portTyped["internal"].(int),
+			external: portTyped["external"].(int),
+			ip:       portTyped["ip"].(string),
+			protocol: portTyped["protocol"].(string),
+		}
+
+		portsMapped = append(portsMapped, portMapped)
+	}
+	sort.Sort(byPort(portsMapped))
+
+	// map the sorted ports to an output structure tf can write
+	outputPorts := make([]interface{}, 0)
+	for _, mappedPort := range portsMapped {
+		outputPort := make(map[string]interface{}, 0)
+		outputPort["internal"] = mappedPort.internal
+		outputPort["external"] = mappedPort.external
+		outputPort["ip"] = mappedPort.ip
+		outputPort["protocol"] = mappedPort.protocol
+		outputPorts = append(outputPorts, outputPort)
+	}
+
+	// store them back to state
+	if err := writer.WriteField([]string{"ports"}, outputPorts); err != nil {
+		return err
+	}
+	for k, v := range writer.Map() {
+		is.Attributes[k] = v
+	}
+
+	return nil
+}