Implement 'bootstrap_on' connection string option

This will allow the forcing of bootstrapping methods

Change-Id: Ia78497222a58f38f2bb4a3b05734ecddcc603f4f
Reviewed-on: http://review.couchbase.org/59530
Reviewed-by: Brett Lawson <brett19@gmail.com>
Tested-by: Mark Nunberg <mark.nunberg@couchbase.com>

bucket_cluster_test.go

@@ -0,0 +1,68 @@
+package gocb
+
+// Get the mock first!
+import (
+	"fmt"
+	"testing"
+)
+
+func TestBadConnstr(t *testing.T) {
+	_, err := Connect(fmt.Sprintf("couchbase://host.com/bucket"))
+	if err == nil {
+		t.Fatal("Explicit bucket should fail for Connect")
+	}
+
+	_, err = Connect("blah://bad_conn_str")
+	if err == nil {
+		t.Fatal("Connection should fail with bad scheme!")
+	}
+	_, err = Connect("couchbase://host.com?bootstrap_on=dummy")
+	if err == nil {
+		t.Fatal("Connection should fail with bad 'bootstrap_on' option")
+	}
+}
+
+func TestBootstrapOn(t *testing.T) {
+	connstr := "couchbase://foo.com,bar.com,baz.com"
+	c, err := Connect(connstr)
+	if err != nil {
+		t.Fatalf("Multi-host connection string failed: %v", err)
+	}
+	if len(c.spec.HttpHosts) != 3 || len(c.spec.MemcachedHosts) != 3 {
+		t.Fatal("Wrong number of hosts for http/memcached")
+	}
+
+	// Use http only
+	c, err = Connect("couchbase://foo.com,bar.com,baz.com?bootstrap_on=http")
+	if err != nil {
+		t.Fatalf("bootstrap_on=http: %v", err)
+	}
+	if len(c.spec.HttpHosts) != 3 {
+		t.Fatalf("HttpHosts is not 3 (%v)", c.spec.HttpHosts)
+	}
+	if len(c.spec.MemcachedHosts) != 0 {
+		t.Fatalf("MemcachedHosts is not 0: %v", c.spec.MemcachedHosts)
+	}
+
+	c, err = Connect("couchbase://foo.com,bar.com,baz.com?bootstrap_on=cccp")
+	if err != nil {
+		t.Fatalf("bootstrap_on=cccp: %v", err)
+	}
+	if len(c.spec.MemcachedHosts) != 3 {
+		t.Fatalf("Expected 3 hosts in memcached: %v", c.spec.MemcachedHosts)
+	}
+	if len(c.spec.HttpHosts) != 0 {
+		t.Fatalf("Expected 0 hosts in http: %v", c.spec.HttpHosts)
+	}
+
+	// Should fail if there are no hosts
+	c, err = Connect("couchbase://foo.com:12000?bootstrap_on=http")
+	if err == nil {
+		t.Fatal("Expected failure with explicit http without http hosts")
+	}
+	c, err = Connect("http://foo.com:9000?bootstrap_on=cccp")
+	if err == nil {
+		t.Fatal("Expected failure with explicit cccp without cccp hosts")
+	}
+
+}

cluster.go

@@ -24,6 +24,27 @@ func Connect(connSpecStr string) (*Cluster, error) {
 	}
 
 	csResolveDnsSrv(&spec)
+
+	// Get bootstrap_on option to determine which, if any, of the bootstrap nodes should be cleared
+	switch spec.Options.Get("bootstrap_on") {
+	case "http":
+		spec.MemcachedHosts = nil
+		if len(spec.HttpHosts) == 0 {
+			return nil, errors.New("bootstrap_on=http but no HTTP hosts in connection string")
+		}
+	case "cccp":
+		spec.HttpHosts = nil
+		if len(spec.MemcachedHosts) == 0 {
+			return nil, errors.New("bootstrap_on=cccp but no CCCP/Memcached hosts in connection string")
+		}
+	case "both":
+	case "":
+		// Do nothing
+		break
+	default:
+		return nil, errors.New("bootstrap_on={http,cccp,both}")
+	}
+
 	cluster := &Cluster{
 		spec:                 spec,
 		connectTimeout:       60000 * time.Millisecond,