DE-1371 Add gocyclo linter

.golangci.yml

@@ -10,6 +10,7 @@ linters:
     - gosimple
     - gosec
     - bodyclose # https://github.com/timakin/bodyclose
+    - gocyclo
     - gomodguard
     - nolintlint
 

messages.go

@@ -681,13 +681,13 @@ type SendableMessage interface {
 func (mg *MailgunImpl) Send(ctx context.Context, m *Message) (mes string, id string, err error) {
 	if mg.domain == "" {
 		err = errors.New("you must provide a valid domain before calling Send()")
-		return
+		return "", "", err
 	}
 
 	invalidChars := ":&'@(),!?#;%+=<>"
 	if i := strings.ContainsAny(mg.domain, invalidChars); i {
 		err = fmt.Errorf("you called Send() with a domain that contains invalid characters")
-		return
+		return "", "", err
 	}
 
 	if mg.apiKey == "" {
@@ -706,133 +706,166 @@ func (mg *MailgunImpl) Send(ctx context.Context, m *Message) (mes string, id str
 	}
 	payload := NewFormDataPayload()
 
-	m.AddValues(payload)
-	for _, to := range m.To() {
-		payload.addValue("to", to)
+	m.Specific.AddValues(payload)
+
+	err = addMessageValues(payload, m)
+	if err != nil {
+		return "", "", err
+	}
+
+	// TODO(v5): remove due for domain agnostic API:
+	if m.Domain() == "" {
+		m.domain = mg.Domain()
 	}
-	for _, tag := range m.Tags() {
-		payload.addValue("o:tag", tag)
+
+	r := newHTTPRequest(generateApiUrlWithDomain(mg, m.Endpoint(), m.Domain()))
+	r.setClient(mg.Client())
+	r.setBasicAuth(basicAuthUser, mg.APIKey())
+	// Override any HTTP headers if provided
+	for k, v := range mg.overrideHeaders {
+		r.addHeader(k, v)
+	}
+
+	var response sendMessageResponse
+	err = postResponseFromJSON(ctx, r, payload, &response)
+	if err == nil {
+		mes = response.Message
+		id = response.Id
+	}
+
+	r.mu.RLock()
+	defer r.mu.RUnlock()
+	if r.capturedCurlOutput != "" {
+		mg.mu.Lock()
+		defer mg.mu.Unlock()
+		mg.capturedCurlOutput = r.capturedCurlOutput
+	}
+
+	return
+}
+
+func addMessageValues(dst *FormDataPayload, src SendableMessage) error {
+	addMessageOptions(dst, src)
+	addMessageHeaders(dst, src)
+
+	err := addMessageVariables(dst, src)
+	if err != nil {
+		return err
+	}
+
+	addMessageAttachment(dst, src)
+
+	return nil
+}
+
+func addMessageOptions(dst *FormDataPayload, src SendableMessage) {
+	for _, to := range src.To() {
+		dst.addValue("to", to)
+	}
+
+	for _, tag := range src.Tags() {
+		dst.addValue("o:tag", tag)
 	}
-	for _, campaign := range m.Campaigns() {
-		payload.addValue("o:campaign", campaign)
+	for _, campaign := range src.Campaigns() {
+		dst.addValue("o:campaign", campaign)
 	}
-	if m.DKIM() != nil {
-		payload.addValue("o:dkim", yesNo(*m.DKIM()))
+	if src.DKIM() != nil {
+		dst.addValue("o:dkim", yesNo(*src.DKIM()))
 	}
-	if !m.DeliveryTime().IsZero() {
-		payload.addValue("o:deliverytime", formatMailgunTime(m.DeliveryTime()))
+	if !src.DeliveryTime().IsZero() {
+		dst.addValue("o:deliverytime", formatMailgunTime(src.DeliveryTime()))
 	}
-	if m.STOPeriod() != "" {
-		payload.addValue("o:deliverytime-optimize-period", m.STOPeriod())
+	if src.STOPeriod() != "" {
+		dst.addValue("o:deliverytime-optimize-period", src.STOPeriod())
 	}
-	if m.NativeSend() {
-		payload.addValue("o:native-send", "yes")
+	if src.NativeSend() {
+		dst.addValue("o:native-send", "yes")
 	}
-	if m.TestMode() {
-		payload.addValue("o:testmode", "yes")
+	if src.TestMode() {
+		dst.addValue("o:testmode", "yes")
 	}
-	if m.Tracking() != nil {
-		payload.addValue("o:tracking", yesNo(*m.Tracking()))
+	if src.Tracking() != nil {
+		dst.addValue("o:tracking", yesNo(*src.Tracking()))
 	}
-	if m.TrackingClicks() != nil {
-		payload.addValue("o:tracking-clicks", *m.TrackingClicks())
+	if src.TrackingClicks() != nil {
+		dst.addValue("o:tracking-clicks", *src.TrackingClicks())
 	}
-	if m.TrackingOpens() != nil {
-		payload.addValue("o:tracking-opens", yesNo(*m.TrackingOpens()))
+	if src.TrackingOpens() != nil {
+		dst.addValue("o:tracking-opens", yesNo(*src.TrackingOpens()))
 	}
-	if m.RequireTLS() {
-		payload.addValue("o:require-tls", trueFalse(m.RequireTLS()))
+	if src.RequireTLS() {
+		dst.addValue("o:require-tls", trueFalse(src.RequireTLS()))
 	}
-	if m.SkipVerification() {
-		payload.addValue("o:skip-verification", trueFalse(m.SkipVerification()))
+	if src.SkipVerification() {
+		dst.addValue("o:skip-verification", trueFalse(src.SkipVerification()))
 	}
-	if m.Headers() != nil {
-		for header, value := range m.Headers() {
-			payload.addValue("h:"+header, value)
+
+	if src.TemplateVersionTag() != "" {
+		dst.addValue("t:version", src.TemplateVersionTag())
+	}
+	if src.TemplateRenderText() {
+		dst.addValue("t:text", yesNo(src.TemplateRenderText()))
+	}
+}
+
+func addMessageHeaders(dst *FormDataPayload, src SendableMessage) {
+	if src.Headers() != nil {
+		for header, value := range src.Headers() {
+			dst.addValue("h:"+header, value)
 		}
 	}
-	if m.Variables() != nil {
-		for variable, value := range m.Variables() {
-			payload.addValue("v:"+variable, value)
+}
+
+func addMessageVariables(dst *FormDataPayload, src SendableMessage) error {
+	if src.Variables() != nil {
+		for variable, value := range src.Variables() {
+			dst.addValue("v:"+variable, value)
 		}
 	}
-	if m.TemplateVariables() != nil {
-		variableString, err := json.Marshal(m.TemplateVariables())
+	if src.TemplateVariables() != nil {
+		variableString, err := json.Marshal(src.TemplateVariables())
 		if err == nil {
 			// the map was marshalled as json so add it
-			payload.addValue("h:X-Mailgun-Variables", string(variableString))
+			dst.addValue("h:X-Mailgun-Variables", string(variableString))
 		}
 	}
-	if m.RecipientVariables() != nil {
-		j, err := json.Marshal(m.RecipientVariables())
+	if src.RecipientVariables() != nil {
+		j, err := json.Marshal(src.RecipientVariables())
 		if err != nil {
-			return "", "", err
+			return err
 		}
-		payload.addValue("recipient-variables", string(j))
+		dst.addValue("recipient-variables", string(j))
 	}
-	if m.Attachments() != nil {
-		for _, attachment := range m.Attachments() {
-			payload.addFile("attachment", attachment)
+
+	return nil
+}
+
+func addMessageAttachment(dst *FormDataPayload, src SendableMessage) {
+	if src.Attachments() != nil {
+		for _, attachment := range src.Attachments() {
+			dst.addFile("attachment", attachment)
 		}
 	}
-	if m.ReaderAttachments() != nil {
-		for _, readerAttachment := range m.ReaderAttachments() {
-			payload.addReadCloser("attachment", readerAttachment.Filename, readerAttachment.ReadCloser)
+	if src.ReaderAttachments() != nil {
+		for _, readerAttachment := range src.ReaderAttachments() {
+			dst.addReadCloser("attachment", readerAttachment.Filename, readerAttachment.ReadCloser)
 		}
 	}
-	if m.BufferAttachments() != nil {
-		for _, bufferAttachment := range m.BufferAttachments() {
-			payload.addBuffer("attachment", bufferAttachment.Filename, bufferAttachment.Buffer)
+	if src.BufferAttachments() != nil {
+		for _, bufferAttachment := range src.BufferAttachments() {
+			dst.addBuffer("attachment", bufferAttachment.Filename, bufferAttachment.Buffer)
 		}
 	}
-	if m.Inlines() != nil {
-		for _, inline := range m.Inlines() {
-			payload.addFile("inline", inline)
+	if src.Inlines() != nil {
+		for _, inline := range src.Inlines() {
+			dst.addFile("inline", inline)
 		}
 	}
-
-	if m.ReaderInlines() != nil {
-		for _, readerAttachment := range m.ReaderInlines() {
-			payload.addReadCloser("inline", readerAttachment.Filename, readerAttachment.ReadCloser)
+	if src.ReaderInlines() != nil {
+		for _, readerAttachment := range src.ReaderInlines() {
+			dst.addReadCloser("inline", readerAttachment.Filename, readerAttachment.ReadCloser)
 		}
 	}
-
-	if m.domain == "" {
-		m.domain = mg.Domain()
-	}
-
-	if m.TemplateVersionTag() != "" {
-		payload.addValue("t:version", m.TemplateVersionTag())
-	}
-
-	if m.TemplateRenderText() {
-		payload.addValue("t:text", yesNo(m.TemplateRenderText()))
-	}
-
-	r := newHTTPRequest(generateApiUrlWithDomain(mg, m.Endpoint(), m.Domain()))
-	r.setClient(mg.Client())
-	r.setBasicAuth(basicAuthUser, mg.APIKey())
-	// Override any HTTP headers if provided
-	for k, v := range mg.overrideHeaders {
-		r.addHeader(k, v)
-	}
-
-	var response sendMessageResponse
-	err = postResponseFromJSON(ctx, r, payload, &response)
-	if err == nil {
-		mes = response.Message
-		id = response.Id
-	}
-
-	r.mu.RLock()
-	defer r.mu.RUnlock()
-	if r.capturedCurlOutput != "" {
-		mg.mu.Lock()
-		defer mg.mu.Unlock()
-		mg.capturedCurlOutput = r.capturedCurlOutput
-	}
-
-	return
 }
 
 func (m *plainMessage) AddValues(p *FormDataPayload) {