Wysyłanie e-maila

Są 2 sposoby wysyłania e-maili przy użyciu interfejsu Gmail API:

  • Możesz go wysłać bezpośrednio za pomocą messages.send.
  • Możesz wysłać go z wersji roboczej za pomocą drafts.send.

E-maile są wysyłane jako ciągi zakodowane w base64url w ramach właściwości raw elementu zasób wiadomości. Ogólne Aby wysłać e-maila, musisz:

  1. Utwórz treść e-maila w wygodny sposób i zakoduj ją jako ciąg base64url.
  2. Utwórz nowy zasób wiadomości i ustaw jego właściwość raw na base64url właśnie utworzony ciąg.
  3. Zadzwoń pod numer messages.send lub drafts.send, jeśli wysyłasz wersję roboczą aby wysłać wiadomość.

Szczegóły tego przepływu pracy mogą się różnić w zależności od wybranego klienta i języka programowania.

Tworzenie wiadomości

Interfejs Gmail API wymaga wiadomości e-mail MIME zgodnych z RFC 2822 i zakodowane jako ciągi w base64url. Wiele języków programowania biblioteki lub narzędzia, które upraszczają proces tworzenia i kodowania MIME. wiadomości. Poniższe przykłady kodu pokazują, jak utworzyć wiadomość MIME w postaci bibliotek klienta interfejsów API Google dla różnych języków.

Java

Tworzenie e-maila można znacznie uprościć dzięki MimeMessage w pakiecie javax.mail.internet. Ten przykład pokazuje, aby utworzyć wiadomość e-mail, wraz z nagłówkami:

gmail/snippets/src/main/java/CreateEmail.java
import java.util.Properties;
import javax.mail.MessagingException;
import javax.mail.Session;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;

/* Class to demonstrate the use of Gmail Create Email API  */
public class CreateEmail {

  /**
   * Create a MimeMessage using the parameters provided.
   *
   * @param toEmailAddress   email address of the receiver
   * @param fromEmailAddress email address of the sender, the mailbox account
   * @param subject          subject of the email
   * @param bodyText         body text of the email
   * @return the MimeMessage to be used to send email
   * @throws MessagingException - if a wrongly formatted address is encountered.
   */
  public static MimeMessage createEmail(String toEmailAddress,
                                        String fromEmailAddress,
                                        String subject,
                                        String bodyText)
      throws MessagingException {
    Properties props = new Properties();
    Session session = Session.getDefaultInstance(props, null);

    MimeMessage email = new MimeMessage(session);

    email.setFrom(new InternetAddress(fromEmailAddress));
    email.addRecipient(javax.mail.Message.RecipientType.TO,
        new InternetAddress(toEmailAddress));
    email.setSubject(subject);
    email.setText(bodyText);
    return email;
  }
}

Następnym krokiem jest zakodowanie MimeMessage i utworzenie instancji Message i ustaw ciąg wiadomości zakodowany w base64url jako wartość klucza Usługa raw.

gmail/snippets/src/main/java/CreateMessage.java
import com.google.api.services.gmail.model.Message;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import javax.mail.MessagingException;
import javax.mail.internet.MimeMessage;
import org.apache.commons.codec.binary.Base64;

/* Class to demonstrate the use of Gmail Create Message API */
public class CreateMessage {

  /**
   * Create a message from an email.
   *
   * @param emailContent Email to be set to raw of message
   * @return a message containing a base64url encoded email
   * @throws IOException        - if service account credentials file not found.
   * @throws MessagingException - if a wrongly formatted address is encountered.
   */
  public static Message createMessageWithEmail(MimeMessage emailContent)
      throws MessagingException, IOException {
    ByteArrayOutputStream buffer = new ByteArrayOutputStream();
    emailContent.writeTo(buffer);
    byte[] bytes = buffer.toByteArray();
    String encodedEmail = Base64.encodeBase64URLSafeString(bytes);
    Message message = new Message();
    message.setRaw(encodedEmail);
    return message;
  }
}

Python

Poniżej znajduje się przykładowy kod pokazujący, jak utworzyć wiadomość MIME zakodowaną w formacie ciąg base64url i przypisanie go do pola raw w tabeli Message. zasób:

gmail/snippet/send mail/create_draft.py
import base64
from email.message import EmailMessage

import google.auth
from googleapiclient.discovery import build
from googleapiclient.errors import HttpError


def gmail_create_draft():
  """Create and insert a draft email.
   Print the returned draft's message and id.
   Returns: Draft object, including draft id and message meta data.

  Load pre-authorized user credentials from the environment.
  TODO(developer) - See https://developers.google.com/identity
  for guides on implementing OAuth2 for the application.
  """
  creds, _ = google.auth.default()

  try:
    # create gmail api client
    service = build("gmail", "v1", credentials=creds)

    message = EmailMessage()

    message.set_content("This is automated draft mail")

    message["To"] = "gduser1@workspacesamples.dev"
    message["From"] = "gduser2@workspacesamples.dev"
    message["Subject"] = "Automated draft"

    # encoded message
    encoded_message = base64.urlsafe_b64encode(message.as_bytes()).decode()

    create_message = {"message": {"raw": encoded_message}}
    # pylint: disable=E1101
    draft = (
        service.users()
        .drafts()
        .create(userId="me", body=create_message)
        .execute()
    )

    print(f'Draft id: {draft["id"]}\nDraft message: {draft["message"]}')

  except HttpError as error:
    print(f"An error occurred: {error}")
    draft = None

  return draft


if __name__ == "__main__":
  gmail_create_draft()

Tworzenie wiadomości z załącznikami

Tworzenie wiadomości z załącznikiem przypomina tworzenie wiadomości ale proces przesyłania pliku jako wieloczęściowego formatu MIME zależy od języka programowania. Następujący kod: przykładowe sposoby tworzenia wieloczęściowej wiadomości MIME za pomocą załącznik.

Java

Poniższy przykład pokazuje, jak utworzyć wieloczęściową wiadomość MIME. są takie same jak powyżej.

gmail/snippets/src/main/java/CreateDraftWithAttachment.java
import com.google.api.client.googleapis.json.GoogleJsonError;
import com.google.api.client.googleapis.json.GoogleJsonResponseException;
import com.google.api.client.http.HttpRequestInitializer;
import com.google.api.client.http.javanet.NetHttpTransport;
import com.google.api.client.json.gson.GsonFactory;
import com.google.api.services.gmail.Gmail;
import com.google.api.services.gmail.GmailScopes;
import com.google.api.services.gmail.model.Draft;
import com.google.api.services.gmail.model.Message;
import com.google.auth.http.HttpCredentialsAdapter;
import com.google.auth.oauth2.GoogleCredentials;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.util.Properties;
import javax.activation.DataHandler;
import javax.activation.DataSource;
import javax.activation.FileDataSource;
import javax.mail.MessagingException;
import javax.mail.Multipart;
import javax.mail.Session;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeBodyPart;
import javax.mail.internet.MimeMessage;
import javax.mail.internet.MimeMultipart;
import org.apache.commons.codec.binary.Base64;

/* Class to demonstrate the use of Gmail Create Draft with attachment API */
public class CreateDraftWithAttachment {
  /**
   * Create a draft email with attachment.
   *
   * @param fromEmailAddress - Email address to appear in the from: header.
   * @param toEmailAddress   - Email address of the recipient.
   * @param file             - Path to the file to be attached.
   * @return the created draft, {@code null} otherwise.
   * @throws MessagingException - if a wrongly formatted address is encountered.
   * @throws IOException        - if service account credentials file not found.
   */
  public static Draft createDraftMessageWithAttachment(String fromEmailAddress,
                                                       String toEmailAddress,
                                                       File file)
      throws MessagingException, IOException {
        /* Load pre-authorized user credentials from the environment.
         TODO(developer) - See https://developers.google.com/identity for
          guides on implementing OAuth2 for your application.*/
    GoogleCredentials credentials = GoogleCredentials.getApplicationDefault()
        .createScoped(GmailScopes.GMAIL_COMPOSE);
    HttpRequestInitializer requestInitializer = new HttpCredentialsAdapter(credentials);

    // Create the gmail API client
    Gmail service = new Gmail.Builder(new NetHttpTransport(),
        GsonFactory.getDefaultInstance(),
        requestInitializer)
        .setApplicationName("Gmail samples")
        .build();

    // Create the email content
    String messageSubject = "Test message";
    String bodyText = "lorem ipsum.";

    // Encode as MIME message
    Properties props = new Properties();
    Session session = Session.getDefaultInstance(props, null);
    MimeMessage email = new MimeMessage(session);
    email.setFrom(new InternetAddress(fromEmailAddress));
    email.addRecipient(javax.mail.Message.RecipientType.TO,
        new InternetAddress(toEmailAddress));
    email.setSubject(messageSubject);

    MimeBodyPart mimeBodyPart = new MimeBodyPart();
    mimeBodyPart.setContent(bodyText, "text/plain");
    Multipart multipart = new MimeMultipart();
    multipart.addBodyPart(mimeBodyPart);
    mimeBodyPart = new MimeBodyPart();
    DataSource source = new FileDataSource(file);
    mimeBodyPart.setDataHandler(new DataHandler(source));
    mimeBodyPart.setFileName(file.getName());
    multipart.addBodyPart(mimeBodyPart);
    email.setContent(multipart);

    // Encode and wrap the MIME message into a gmail message
    ByteArrayOutputStream buffer = new ByteArrayOutputStream();
    email.writeTo(buffer);
    byte[] rawMessageBytes = buffer.toByteArray();
    String encodedEmail = Base64.encodeBase64URLSafeString(rawMessageBytes);
    Message message = new Message();
    message.setRaw(encodedEmail);

    try {
      // Create the draft message
      Draft draft = new Draft();
      draft.setMessage(message);
      draft = service.users().drafts().create("me", draft).execute();
      System.out.println("Draft id: " + draft.getId());
      System.out.println(draft.toPrettyString());
      return draft;
    } catch (GoogleJsonResponseException e) {
      // TODO(developer) - handle error appropriately
      GoogleJsonError error = e.getDetails();
      if (error.getCode() == 403) {
        System.err.println("Unable to create draft: " + e.getDetails());
      } else {
        throw e;
      }
    }
    return null;
  }
}

Python

Podobnie jak w poprzednim przykładzie, tu również obsługujemy kodowanie do base64url i przypisanie jej do pola raw w Message .

gmail/snippet/send mail/create_draft_with_attachment.py
import base64
import mimetypes
import os
from email.message import EmailMessage
from email.mime.audio import MIMEAudio
from email.mime.base import MIMEBase
from email.mime.image import MIMEImage
from email.mime.text import MIMEText

import google.auth
from googleapiclient.discovery import build
from googleapiclient.errors import HttpError


def gmail_create_draft_with_attachment():
  """Create and insert a draft email with attachment.
   Print the returned draft's message and id.
  Returns: Draft object, including draft id and message meta data.

  Load pre-authorized user credentials from the environment.
  TODO(developer) - See https://developers.google.com/identity
  for guides on implementing OAuth2 for the application.
  """
  creds, _ = google.auth.default()

  try:
    # create gmail api client
    service = build("gmail", "v1", credentials=creds)
    mime_message = EmailMessage()

    # headers
    mime_message["To"] = "gduser1@workspacesamples.dev"
    mime_message["From"] = "gduser2@workspacesamples.dev"
    mime_message["Subject"] = "sample with attachment"

    # text
    mime_message.set_content(
        "Hi, this is automated mail with attachment.Please do not reply."
    )

    # attachment
    attachment_filename = "photo.jpg"
    # guessing the MIME type
    type_subtype, _ = mimetypes.guess_type(attachment_filename)
    maintype, subtype = type_subtype.split("/")

    with open(attachment_filename, "rb") as fp:
      attachment_data = fp.read()
    mime_message.add_attachment(attachment_data, maintype, subtype)

    encoded_message = base64.urlsafe_b64encode(mime_message.as_bytes()).decode()

    create_draft_request_body = {"message": {"raw": encoded_message}}
    # pylint: disable=E1101
    draft = (
        service.users()
        .drafts()
        .create(userId="me", body=create_draft_request_body)
        .execute()
    )
    print(f'Draft id: {draft["id"]}\nDraft message: {draft["message"]}')
  except HttpError as error:
    print(f"An error occurred: {error}")
    draft = None
  return draft


def build_file_part(file):
  """Creates a MIME part for a file.

  Args:
    file: The path to the file to be attached.

  Returns:
    A MIME part that can be attached to a message.
  """
  content_type, encoding = mimetypes.guess_type(file)

  if content_type is None or encoding is not None:
    content_type = "application/octet-stream"
  main_type, sub_type = content_type.split("/", 1)
  if main_type == "text":
    with open(file, "rb"):
      msg = MIMEText("r", _subtype=sub_type)
  elif main_type == "image":
    with open(file, "rb"):
      msg = MIMEImage("r", _subtype=sub_type)
  elif main_type == "audio":
    with open(file, "rb"):
      msg = MIMEAudio("r", _subtype=sub_type)
  else:
    with open(file, "rb"):
      msg = MIMEBase(main_type, sub_type)
      msg.set_payload(file.read())
  filename = os.path.basename(file)
  msg.add_header("Content-Disposition", "attachment", filename=filename)
  return msg


if __name__ == "__main__":
  gmail_create_draft_with_attachment()

Wysyłanie wiadomości

Utworzoną wiadomość możesz wysłać, podając ją w treść żądania wywołania do messages.send, jak zaprezentowaliśmy. w poniższych przykładach.

Java

gmail/snippets/src/main/java/SendMessage.java
import com.google.api.client.googleapis.json.GoogleJsonError;
import com.google.api.client.googleapis.json.GoogleJsonResponseException;
import com.google.api.client.http.HttpRequestInitializer;
import com.google.api.client.http.javanet.NetHttpTransport;
import com.google.api.client.json.gson.GsonFactory;
import com.google.api.services.gmail.Gmail;
import com.google.api.services.gmail.GmailScopes;
import com.google.api.services.gmail.model.Message;
import com.google.auth.http.HttpCredentialsAdapter;
import com.google.auth.oauth2.GoogleCredentials;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.Properties;
import javax.mail.MessagingException;
import javax.mail.Session;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;
import org.apache.commons.codec.binary.Base64;

/* Class to demonstrate the use of Gmail Send Message API */
public class SendMessage {
  /**
   * Send an email from the user's mailbox to its recipient.
   *
   * @param fromEmailAddress - Email address to appear in the from: header
   * @param toEmailAddress   - Email address of the recipient
   * @return the sent message, {@code null} otherwise.
   * @throws MessagingException - if a wrongly formatted address is encountered.
   * @throws IOException        - if service account credentials file not found.
   */
  public static Message sendEmail(String fromEmailAddress,
                                  String toEmailAddress)
      throws MessagingException, IOException {
        /* Load pre-authorized user credentials from the environment.
           TODO(developer) - See https://developers.google.com/identity for
            guides on implementing OAuth2 for your application.*/
    GoogleCredentials credentials = GoogleCredentials.getApplicationDefault()
        .createScoped(GmailScopes.GMAIL_SEND);
    HttpRequestInitializer requestInitializer = new HttpCredentialsAdapter(credentials);

    // Create the gmail API client
    Gmail service = new Gmail.Builder(new NetHttpTransport(),
        GsonFactory.getDefaultInstance(),
        requestInitializer)
        .setApplicationName("Gmail samples")
        .build();

    // Create the email content
    String messageSubject = "Test message";
    String bodyText = "lorem ipsum.";

    // Encode as MIME message
    Properties props = new Properties();
    Session session = Session.getDefaultInstance(props, null);
    MimeMessage email = new MimeMessage(session);
    email.setFrom(new InternetAddress(fromEmailAddress));
    email.addRecipient(javax.mail.Message.RecipientType.TO,
        new InternetAddress(toEmailAddress));
    email.setSubject(messageSubject);
    email.setText(bodyText);

    // Encode and wrap the MIME message into a gmail message
    ByteArrayOutputStream buffer = new ByteArrayOutputStream();
    email.writeTo(buffer);
    byte[] rawMessageBytes = buffer.toByteArray();
    String encodedEmail = Base64.encodeBase64URLSafeString(rawMessageBytes);
    Message message = new Message();
    message.setRaw(encodedEmail);

    try {
      // Create send message
      message = service.users().messages().send("me", message).execute();
      System.out.println("Message id: " + message.getId());
      System.out.println(message.toPrettyString());
      return message;
    } catch (GoogleJsonResponseException e) {
      // TODO(developer) - handle error appropriately
      GoogleJsonError error = e.getDetails();
      if (error.getCode() == 403) {
        System.err.println("Unable to send message: " + e.getDetails());
      } else {
        throw e;
      }
    }
    return null;
  }
}

Python

gmail/snippet/send mail/send_message.py
import base64
from email.message import EmailMessage

import google.auth
from googleapiclient.discovery import build
from googleapiclient.errors import HttpError


def gmail_send_message():
  """Create and send an email message
  Print the returned  message id
  Returns: Message object, including message id

  Load pre-authorized user credentials from the environment.
  TODO(developer) - See https://developers.google.com/identity
  for guides on implementing OAuth2 for the application.
  """
  creds, _ = google.auth.default()

  try:
    service = build("gmail", "v1", credentials=creds)
    message = EmailMessage()

    message.set_content("This is automated draft mail")

    message["To"] = "gduser1@workspacesamples.dev"
    message["From"] = "gduser2@workspacesamples.dev"
    message["Subject"] = "Automated draft"

    # encoded message
    encoded_message = base64.urlsafe_b64encode(message.as_bytes()).decode()

    create_message = {"raw": encoded_message}
    # pylint: disable=E1101
    send_message = (
        service.users()
        .messages()
        .send(userId="me", body=create_message)
        .execute()
    )
    print(f'Message Id: {send_message["id"]}')
  except HttpError as error:
    print(f"An error occurred: {error}")
    send_message = None
  return send_message


if __name__ == "__main__":
  gmail_send_message()

Jeśli próbujesz wysłać odpowiedź i chcesz, aby e-mail został podzielony na wątki, sprawdź, czy:

  1. Nagłówki Subject są takie same
  2. Nagłówki References i In-Reply-To są następujące po standardu RFC 2822.

Informacje o wysyłaniu wiadomości z wersji roboczej znajdziesz w artykule Tworzenie wersji roboczych