How send Email using Gmail api in swift

Question

The Gmail Api has no clear documentation on how to do this, I have been trying with this but there are many things that are in the air.

I have sought external source

Answer 1

According to Google API documentation(https://developers.google.com/gmail/api/guides/sending), we can know there are have two ways can help you send message success(draft.send, message.send). without a doubt, both of them use api are different, but the result is the same. As you give one of the above way can got that, we just call it message.send. With another way is draft.send, so we should upload "UploadParameters" to Gmail draft, after we upload success, we can get some message about gmail draft. At last, we should send mail content, when we send success, the draft message will automatic delete. Code goes be as follows:

func postEmailMessageRequest(model: MEMailMessageModel, request: CompletionRequest) {

        let uploadParameters = GTLUploadParameters()
        uploadParameters.data = model.snippet.dataUsingEncoding(NSUTF8StringEncoding)
        uploadParameters.MIMEType = model.mimeType!

        let query = GTLQueryGmail.queryForUsersDraftsCreateWithUploadParameters(uploadParameters) as! GTLQueryProtocol!
        service.executeQuery(query) { (ticket : GTLServiceTicket!, messages : AnyObject!, error : NSError?) -> Void in
            if error == nil {
                let messages = (messages as! GTLGmailDraft)
                messages.message.threadId = model.threadID
                self.sendMailRequest(messages, model: model, request: request)
            } else {
                request(status: false, result: "upload success")
            }
        }
    }

    func sendMailRequest(draft: GTLGmailDraft, model: MEMailMessageModel, request: CompletionRequest) {

        let query = GTLQueryGmail.queryForUsersDraftsSendWithUploadParameters(nil) as! GTLQueryGmail
        draft.message.raw = self.generateRawString(model)
        query.draft = draft

        self.service.executeQuery(query, completionHandler: { (ticket, response, error) -> Void in
            if error == nil {
                request(status: true, result: "send success") // after this, the draft will be delete
            } else {
                request(status: false, result: "send failure")
            }
        })
    }

    func generateRawString(model: MEMailMessageModel) -> String {
        let date = MEMailMessagelFormatUtil.coverDateFromDate(NSDate(), dateFormat: "EEE, dd MMM yyyy HH:mm:ss Z")! // get current date

        var fromEamil = ""
        if let str = NSUserDefaults.standardUserDefaults().valueForKey("userEmail") as? String {
            fromEamil = str
        }

        var rawMessage = ""
        if model.isReply { // how to reply, but how to reply the email is another question.
            rawMessage = "" + "In-Reply-To: \(model.messageID!)\r\n"
            if let references = model.references {
                rawMessage += "References: \(references) \(model.messageID!)\r\n"
            } else {
                rawMessage += "References: \(model.messageID!)\r\n"
            }
        }

        rawMessage += "Date: \(date)\r\n" +
            "From: <\(fromEamil)>\r\n" +
            "To: \(model.toName!) <\(model.toMail)>\r\n" +
            "Subject: \(model.subject) \r\n\r\n" + "\(model.snippet)"

        return GTLEncodeWebSafeBase64(rawMessage.dataUsingEncoding(NSUTF8StringEncoding))
    }