Trigger new snapshot if scopes are different from before.

changes.go

diff --git a/changes.go b/changes.go
index 0b77cba..e7a9289 100644
--- a/changes.go
+++ b/changes.go
@@ -2,14 +2,14 @@
 
 import (
 	"encoding/json"
+	"github.com/apigee-labs/transicator/common"
 	"io/ioutil"
 	"net/http"
 	"net/url"
 	"path"
-	"time"
-
-	"github.com/apigee-labs/transicator/common"
+	"sort"
 	"sync/atomic"
+	"time"
 )
 
 var lastSequence string
@@ -251,6 +251,17 @@
 
 	updateSequence(resp.LastSequence)
 
+	/*
+	 * Check to see if there was any change in scope. If found, handle it
+	 * by getting a new snapshot
+	 */
+	newScopes := findScopesForId(apidInfo.ClusterID)
+	cs := scopeChanged(newScopes, scopes)
+	if cs != nil {
+		log.Debugf("Detected scope changes, going to fetch a new snapshot to sync...")
+		return cs
+	}
+
 	return nil
 }
 
@@ -316,3 +327,25 @@
 	}
 
 }
+
+/*
+ * Returns nil if the two arrays have matching contents
+ */
+func scopeChanged(a, b []string) error {
+
+	if len(a) != len(b) {
+		return changeServerError{
+			Code: "Scope changes detected; must get new snapshot",
+		}
+	}
+	sort.Strings(a)
+	sort.Strings(b)
+	for i, v := range a {
+		if v != b[i] {
+			return changeServerError{
+				Code: "Scope changes detected; must get new snapshot",
+			}
+		}
+	}
+	return nil
+}

listener_test.go

diff --git a/listener_test.go b/listener_test.go
index ee0b4cc..b5fea9b 100644
--- a/listener_test.go
+++ b/listener_test.go
@@ -50,6 +50,22 @@
 			Expect(func() { handler.Handle(&event) }).To(Panic())
 		}, 3)
 
+		It("should fail if more than one apid_cluster rows", func() {
+			newScopes := []string{"foo"}
+			scopes := []string{"bar"}
+			Expect(scopeChanged(newScopes, scopes)).To(Equal(changeServerError{Code: "Scope changes detected; must get new snapshot"}))
+			newScopes = []string{"foo", "bar"}
+			scopes = []string{"bar"}
+			Expect(scopeChanged(newScopes, scopes)).To(Equal(changeServerError{Code: "Scope changes detected; must get new snapshot"}))
+			newScopes = []string{"foo"}
+			scopes = []string{"bar", "foo"}
+			Expect(scopeChanged(newScopes, scopes)).To(Equal(changeServerError{Code: "Scope changes detected; must get new snapshot"}))
+			newScopes = []string{"foo", "bar"}
+			scopes = []string{"bar", "foo"}
+			Expect(scopeChanged(newScopes, scopes)).To(BeNil())
+
+		}, 3)
+
 		It("should process a valid Snapshot", func() {
 
 			event := common.Snapshot{
@@ -329,6 +345,7 @@
 				Expect(len(scopes)).To(Equal(2))
 				Expect(scopes[0]).To(Equal("s1"))
 				Expect(scopes[1]).To(Equal("s2"))
+
 			}, 3)
 
 			It("delete event should delete", func() {