Merge pull request #90 from nyaruka/jiochat-media-req-builder-interface

Add interface for media download request builder

backends/rapidpro/msg.go

@@ -58,10 +58,12 @@ func writeMsg(ctx context.Context, b *backend, msg courier.Msg) error {
 		return nil
 	}
 
+	channel := m.Channel()
+
 	// if we have media, go download it to S3
 	for i, attachment := range m.Attachments_ {
 		if strings.HasPrefix(attachment, "http") {
-			url, err := downloadMediaToS3(b, m.OrgID_, m.UUID_, attachment)
+			url, err := downloadMediaToS3(ctx, b, channel, m.OrgID_, m.UUID_, attachment)
 			if err != nil {
 				return err
 			}
@@ -181,17 +183,37 @@ func readMsgFromDB(b *backend, id courier.MsgID) (*DBMsg, error) {
 // Media download and classification
 //-----------------------------------------------------------------------------
 
-func downloadMediaToS3(b *backend, orgID OrgID, msgUUID courier.MsgUUID, mediaURL string) (string, error) {
+func downloadMediaToS3(ctx context.Context, b *backend, channel courier.Channel, orgID OrgID, msgUUID courier.MsgUUID, mediaURL string) (string, error) {
+
 	parsedURL, err := url.Parse(mediaURL)
 	if err != nil {
 		return "", err
 	}
 
-	// first fetch our media
-	req, err := http.NewRequest("GET", mediaURL, nil)
-	if err != nil {
-		return "", err
+	var req *http.Request
+	handler := courier.GetHandler(channel.ChannelType())
+	if handler != nil {
+		mediaDownloadRequestBuilder, isMediaDownloadRequestBuilder := handler.(courier.MediaDownloadRequestBuilder)
+		if isMediaDownloadRequestBuilder {
+			req, err = mediaDownloadRequestBuilder.BuildDownloadMediaRequest(ctx, channel, parsedURL.String())
+
+			// in the case of errors, we log the error but move onwards anyways
+			if err != nil {
+				logrus.WithField("channel_uuid", channel.UUID()).WithField("channel_type", channel.ChannelType()).WithField("media_url", mediaURL).WithError(err).Error("unable to build media download request")
+			}
+		}
 	}
+
+	if req == nil {
+
+		// first fetch our media
+		req, err = http.NewRequest("GET", mediaURL, nil)
+		if err != nil {
+			return "", err
+		}
+
+	}
+
 	resp, err := utils.GetHTTPClient().Do(req)
 	if err != nil {
 		return "", err

handler.go

@@ -31,6 +31,11 @@ type URNDescriber interface {
 	DescribeURN(context.Context, Channel, urns.URN) (map[string]string, error)
 }
 
+// MediaDownloadRequestBuilder is the interface handlers which can allow a custom way to download attachment media for messages should satisfy
+type MediaDownloadRequestBuilder interface {
+	BuildDownloadMediaRequest(context.Context, Channel, string) (*http.Request, error)
+}
+
 // RegisterHandler adds a new handler for a channel type, this is called by individual handlers when they are initialized
 func RegisterHandler(handler ChannelHandler) {
 	registeredHandlers[handler.ChannelType()] = handler

handlers/jiochat/jiochat.go

@@ -192,3 +192,22 @@ func (h *handler) DescribeURN(ctx context.Context, channel courier.Channel, urn
 
 	return map[string]string{"name": nickname}, nil
 }
+
+// BuildDownloadMediaRequest download media for message attachment
+func (h *handler) BuildDownloadMediaRequest(ctx context.Context, channel courier.Channel, attachmentURL string) (*http.Request, error) {
+	parsedURL, err := url.Parse(attachmentURL)
+	if err != nil {
+		return nil, err
+	}
+
+	accessToken := getAccessToken(channel)
+
+	// first fetch our media
+	req, err := http.NewRequest("GET", parsedURL.String(), nil)
+	req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", accessToken))
+	if err != nil {
+		return nil, err
+	}
+
+	return req, nil
+}