respect flow channels, if defined.

flows/actions/send_msg.go

@@ -7,6 +7,7 @@ import (
 	"github.com/nyaruka/goflow/envs"
 	"github.com/nyaruka/goflow/flows"
 	"github.com/nyaruka/goflow/flows/events"
+	"math/rand"
 )
 
 func init() {
@@ -83,7 +84,16 @@ func (a *SendMsgAction) Execute(run flows.Run, step flows.Step, logModifier flow
 
 	evaluatedText, evaluatedAttachments, evaluatedQuickReplies := a.evaluateMessage(run, nil, a.Text, a.Attachments, a.QuickReplies, logEvent)
 
-	destinations := run.Contact().ResolveDestinations(a.AllURNs)
+	var destinations []flows.Destination
+	//<*((==<
+	flowChannels := run.Flow().Channels()
+	if len(flowChannels) > 0 {
+		destinations = []flows.Destination{}
+		// just add one "null" entry
+		destinations = append(destinations, flows.Destination{URN: nil, Channel: nil})
+	} else {
+		destinations = run.Contact().ResolveDestinations(a.AllURNs)
+	}
 
 	sa := run.Session().Assets()
 
@@ -92,6 +102,18 @@ func (a *SendMsgAction) Execute(run flows.Run, step flows.Step, logModifier flow
 		var channelRef *assets.ChannelReference
 		if dest.Channel != nil {
 			channelRef = assets.NewChannelReference(dest.Channel.UUID(), dest.Channel.Name())
+		} else if dest.URN == nil {
+			//<*((==<
+			channelRef = flowChannels[rand.Intn(len(flowChannels))]
+			//pick URN from contact based on channel we have
+			dest.URN = run.Contact().ResolveURN(channelRef.UUID)
+			if dest.URN == nil {
+				logEvent(events.NewErrorf("no matching URN for contact [%s] with channel [%s]",
+					run.Contact().UUID(),
+					channelRef.UUID,
+				))
+				return nil
+			}
 		}
 
 		var templating *flows.MsgTemplating

flows/contact.go

@@ -379,6 +379,18 @@ func (c *Contact) ResolveDestinations(all bool) []Destination {
 	return destinations
 }
 
+//<*((==<
+// ResolveURN resolves possible URN given channel to use
+func (c *Contact) ResolveURN(aChannelID assets.ChannelUUID) *ContactURN {
+	for _, u := range c.urns {
+		channel := c.assets.Channels().Get(aChannelID)
+		if channel != nil && channel.SupportsScheme(u.URN().Scheme()) {
+			return u
+		}
+	}
+	return nil
+}
+
 // PreferredURN gets the preferred URN for this contact, i.e. the URN we would use for sending
 func (c *Contact) PreferredURN() *ContactURN {
 	destinations := c.ResolveDestinations(false)

flows/definition/flow.go

@@ -38,6 +38,7 @@ type flow struct {
 	expireAfterMinutes int
 	localization       flows.Localization
 	nodes              []flows.Node
+	channels []*assets.ChannelReference //<*((==<
 
 	// optional properties not used by engine itself
 	ui json.RawMessage
@@ -50,7 +51,7 @@ type flow struct {
 }
 
 // NewFlow creates a new flow
-func NewFlow(uuid assets.FlowUUID, name string, language envs.Language, flowType flows.FlowType, revision int, expireAfterMinutes int, localization flows.Localization, nodes []flows.Node, ui json.RawMessage, a assets.Flow) (flows.Flow, error) {
+func NewFlow(uuid assets.FlowUUID, name string, language envs.Language, flowType flows.FlowType, revision int, expireAfterMinutes int, localization flows.Localization, nodes []flows.Node, ui json.RawMessage, a assets.Flow, channels []*assets.ChannelReference) (flows.Flow, error) {
 	f := &flow{
 		uuid:               uuid,
 		name:               name,
@@ -64,6 +65,7 @@ func NewFlow(uuid assets.FlowUUID, name string, language envs.Language, flowType
 		nodeMap:            make(map[flows.NodeUUID]flows.Node, len(nodes)),
 		ui:                 ui,
 		asset:              a,
+		channels: channels,
 	}
 
 	for _, node := range f.nodes {
@@ -88,6 +90,7 @@ func (f *flow) Nodes() []flows.Node                    { return f.nodes }
 func (f *flow) Localization() flows.Localization       { return f.localization }
 func (f *flow) UI() json.RawMessage                    { return f.ui }
 func (f *flow) GetNode(uuid flows.NodeUUID) flows.Node { return f.nodeMap[uuid] }
+func (f *flow) Channels() []*assets.ChannelReference { return f.channels } //<*((==<
 
 func (f *flow) validate() error {
 	// track UUIDs used by nodes and actions to ensure that they are unique
@@ -315,6 +318,8 @@ type flowEnvelope struct {
 	Localization       localization    `json:"localization"`
 	Nodes              []*node         `json:"nodes"`
 	UI                 json.RawMessage `json:"_ui,omitempty"`
+	//<*((==<
+	ChannelUUIDs []assets.ChannelUUID `json:"channels,omitempty"`
 }
 
 // ReadFlow reads a flow definition from the passed in byte array, migrating it to the spec version of the engine if necessary
@@ -355,7 +360,13 @@ func readFlow(data json.RawMessage, mc *migrations.Config, a assets.Flow) (flows
 		e.Localization = make(localization)
 	}
 
-	return NewFlow(e.UUID, e.Name, e.Language, e.Type, e.Revision, e.ExpireAfterMinutes, e.Localization, nodes, e.UI, a)
+	//<*((==<
+	channels := make([]*assets.ChannelReference, len(e.ChannelUUIDs))
+	for i := range e.ChannelUUIDs {
+		channels[i] = assets.NewChannelReference(e.ChannelUUIDs[i], string("Name Of: "+e.ChannelUUIDs[i]))
+	}
+
+	return NewFlow(e.UUID, e.Name, e.Language, e.Type, e.Revision, e.ExpireAfterMinutes, e.Localization, nodes, e.UI, a, channels)
 }
 
 // MarshalJSON marshals this flow into JSON

flows/definition/flow_test.go

@@ -273,6 +273,7 @@ func TestNewFlow(t *testing.T) {
 		},
 		nil, // no UI
 		nil, // no asset
+		nil,
 	)
 	require.NoError(t, err)
 

flows/interfaces.go

@@ -136,6 +136,7 @@ type Flow interface {
 	UI() json.RawMessage
 	Nodes() []Node
 	GetNode(uuid NodeUUID) Node
+	Channels() []*assets.ChannelReference //<*((==<
 
 	Asset() assets.Flow
 	Reference() *assets.FlowReference