Split twilio messages at 1600 chars

nyaruka · Sep 15, 2017 · cb3ee75 · cb3ee75
1 parent cbf978b
commit cb3ee75
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Showing 4 changed files with 104 additions and 53 deletions.
diff --git a/handlers/base.go b/handlers/base.go
@@ -1,6 +1,7 @@
 package handlers
 
 import (
+	"bytes"
 	"encoding/base64"
 	"encoding/json"
 	"fmt"
@@ -189,3 +190,26 @@ func DecodePossibleBase64(original string) string {
 
 	return decoded
 }
+
+// SplitMsg splits the passed in string into segments that are at most max length
+func SplitMsg(text string, max int) []string {
+	// smaller than our max, just return it
+	if len(text) <= max {
+		return []string{text}
+	}
+
+	parts := make([]string, 0, 2)
+	part := bytes.Buffer{}
+	for _, r := range text {
+		part.WriteRune(r)
+		if part.Len() == max || (part.Len() > max-6 && r == ' ') {
+			parts = append(parts, strings.TrimSpace(part.String()))
+			part.Reset()
+		}
+	}
+	if part.Len() > 0 {
+		parts = append(parts, strings.TrimSpace(part.String()))
+	}
+
+	return parts
+}
diff --git a/handlers/base_test.go b/handlers/base_test.go
@@ -34,3 +34,12 @@ func TestDecodePossibleBase64(t *testing.T) {
 	assert.Contains(DecodePossibleBase64("Tm93IGlzDQp0aGUgdGltZQ0KZm9yIGFsbCBnb29kDQpwZW9wbGUgdG8NCnJlc2lzdC4NCg0KSG93IGFib3V0IGhhaWt1cz8NCkkgZmluZCB0aGVtIHRvIGJlIGZyaWVuZGx5Lg0KcmVmcmlnZXJhdG9yDQoNCjAxMjM0NTY3ODkNCiFAIyQlXiYqKCkgW117fS09Xys7JzoiLC4vPD4/fFx+YA0KQUJDREVGR0hJSktMTU5PUFFSU1RVVldYWVphYmNkZWZnaGlqa2xtbm9wcXJzdHV2d3h5eg=="), "I find them to be friendly")
 	assert.Contains(DecodePossibleBase64(test6), "I received your letter today")
 }
+
+func TestSplitMsg(t *testing.T) {
+	assert := assert.New(t)
+	assert.Equal([]string{""}, SplitMsg("", 160))
+	assert.Equal([]string{"Simple message"}, SplitMsg("Simple message", 160))
+	assert.Equal([]string{"This is a message", "longer than 10"}, SplitMsg("This is a message longer than 10", 20))
+	assert.Equal([]string{" "}, SplitMsg(" ", 20))
+	assert.Equal([]string{"This is a message", "longer than 10"}, SplitMsg("This is a message   longer than 10", 20))
+}
diff --git a/handlers/twilio/twilio.go b/handlers/twilio/twilio.go
@@ -31,6 +31,7 @@ const configSendURL = "send_url"
 
 const twSignatureHeader = "X-Twilio-Signature"
 
+var maxMsgLength = 1600
 var sendURL = "https://api.twilio.com/2010-04-01/Accounts"
 
 // error code twilio returns when a contact has sent "stop"
@@ -185,69 +186,76 @@ func (h *handler) SendMsg(msg courier.Msg) (courier.MsgStatus, error) {
 		return nil, fmt.Errorf("missing account auth token for twilio channel")
 	}
 
-	// build our request
-	form := url.Values{
-		"To":             []string{msg.URN().Path()},
-		"Body":           []string{msg.Text()},
-		"StatusCallback": []string{callbackURL},
-	}
+	status := h.Backend().NewMsgStatusForID(msg.Channel(), msg.ID(), courier.MsgErrored)
+	parts := handlers.SplitMsg(msg.Text(), maxMsgLength)
+	for i, part := range parts {
+		// build our request
+		form := url.Values{
+			"To":             []string{msg.URN().Path()},
+			"Body":           []string{part},
+			"StatusCallback": []string{callbackURL},
+		}
 
-	// add any media URL
-	if len(msg.Attachments()) > 0 {
-		_, mediaURL := courier.SplitAttachment(msg.Attachments()[0])
-		form["MediaUrl"] = []string{mediaURL}
-	}
+		// add any media URL to the first part
+		if len(msg.Attachments()) > 0 && i == 0 {
+			_, mediaURL := courier.SplitAttachment(msg.Attachments()[0])
+			form["MediaUrl"] = []string{mediaURL}
+		}
 
-	// set our from, either as a messaging service or from our address
-	serviceSID := msg.Channel().StringConfigForKey(configMessagingServiceSID, "")
-	if serviceSID != "" {
-		form["MessagingServiceSID"] = []string{serviceSID}
-	} else {
-		form["From"] = []string{msg.Channel().Address()}
-	}
+		// set our from, either as a messaging service or from our address
+		serviceSID := msg.Channel().StringConfigForKey(configMessagingServiceSID, "")
+		if serviceSID != "" {
+			form["MessagingServiceSID"] = []string{serviceSID}
+		} else {
+			form["From"] = []string{msg.Channel().Address()}
+		}
 
-	baseSendURL := msg.Channel().StringConfigForKey(configSendURL, sendURL)
-	sendURL, err := utils.AddURLPath(baseSendURL, accountSID, "Messages.json")
-	if err != nil {
-		return nil, err
-	}
+		baseSendURL := msg.Channel().StringConfigForKey(configSendURL, sendURL)
+		sendURL, err := utils.AddURLPath(baseSendURL, accountSID, "Messages.json")
+		if err != nil {
+			return nil, err
+		}
 
-	req, err := http.NewRequest(http.MethodPost, sendURL, strings.NewReader(form.Encode()))
-	req.SetBasicAuth(accountSID, accountToken)
-	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
-	req.Header.Set("Accept", "application/json")
-	rr, err := utils.MakeHTTPRequest(req)
+		req, err := http.NewRequest(http.MethodPost, sendURL, strings.NewReader(form.Encode()))
+		req.SetBasicAuth(accountSID, accountToken)
+		req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+		req.Header.Set("Accept", "application/json")
+		rr, err := utils.MakeHTTPRequest(req)
 
-	// record our status and log
-	status := h.Backend().NewMsgStatusForID(msg.Channel(), msg.ID(), courier.MsgErrored)
-	log := courier.NewChannelLogFromRR("Message Sent", msg.Channel(), msg.ID(), rr).WithError("Message Send Error", err)
-	status.AddLog(log)
+		// record our status and log
+		log := courier.NewChannelLogFromRR("Message Sent", msg.Channel(), msg.ID(), rr).WithError("Message Send Error", err)
+		status.AddLog(log)
 
-	// fail if we received an error
-	if err != nil {
-		return status, nil
-	}
+		// fail if we received an error
+		if err != nil {
+			return status, nil
+		}
 
-	// was this request successful?
-	errorCode, _ := jsonparser.GetInt([]byte(rr.Body), "error_code")
-	if errorCode != 0 {
-		if errorCode == errorStopped {
-			status.SetStatus(courier.MsgFailed)
-			h.Backend().StopMsgContact(msg)
+		// was this request successful?
+		errorCode, _ := jsonparser.GetInt([]byte(rr.Body), "error_code")
+		if errorCode != 0 {
+			if errorCode == errorStopped {
+				status.SetStatus(courier.MsgFailed)
+				h.Backend().StopMsgContact(msg)
+			}
+			log.WithError("Message Send Error", errors.Errorf("received error code from twilio '%d'", errorCode))
+			return status, nil
 		}
-		log.WithError("Message Send Error", errors.Errorf("received error code from twilio '%d'", errorCode))
-		return status, nil
-	}
 
-	// grab the external id
-	externalID, err := jsonparser.GetString([]byte(rr.Body), "sid")
-	if err != nil {
-		log.WithError("Message Send Error", errors.Errorf("unable to get sid from body"))
-		return status, nil
-	}
+		// grab the external id
+		externalID, err := jsonparser.GetString([]byte(rr.Body), "sid")
+		if err != nil {
+			log.WithError("Message Send Error", errors.Errorf("unable to get sid from body"))
+			return status, nil
+		}
 
-	status.SetStatus(courier.MsgWired)
-	status.SetExternalID(externalID)
+		status.SetStatus(courier.MsgWired)
+
+		// only save the first external id
+		if i == 0 {
+			status.SetExternalID(externalID)
+		}
+	}
 
 	return status, nil
 }

diff --git a/handlers/twilio/twilio_test.go b/handlers/twilio/twilio_test.go
@@ -92,6 +92,15 @@ var defaultSendTestCases = []ChannelSendTestCase{
 		Path:       "/Account/accountSID/Messages.json",
 		Headers:    map[string]string{"Authorization": "Basic YWNjb3VudFNJRDphdXRoVG9rZW4="},
 		SendPrep:   setSendURL},
+	{Label: "Long Send",
+		Text:   "This is a longer message than 160 characters and will cause us to split it into two separate parts, isn't that right but it is even longer than before I say, I need to keep adding more things to make it work",
+		URN:    "tel:+250788383383",
+		Status: "W", ExternalID: "1002",
+		ResponseBody: `{ "sid": "1002" }`, ResponseStatus: 200,
+		PostParams: map[string]string{"Body": "I need to keep adding more things to make it work", "To": "+250788383383"},
+		Path:       "/Account/accountSID/Messages.json",
+		Headers:    map[string]string{"Authorization": "Basic YWNjb3VudFNJRDphdXRoVG9rZW4="},
+		SendPrep:   setSendURL},
 	{Label: "Error Sending",
 		Text: "Error Message", URN: "tel:+250788383383",
 		Status:       "E",
@@ -126,6 +135,7 @@ var defaultSendTestCases = []ChannelSendTestCase{
 }
 
 func TestSending(t *testing.T) {
+	maxMsgLength = 160
 	var defaultChannel = courier.NewMockChannel("8eb23e93-5ecb-45ba-b726-3b064e0c56ab", "T", "2020", "US",
 		map[string]interface{}{
 			configAccountSID:        "accountSID",