javascript - GmailApp - 为特定邮件添加标签，而不是线程

Question

我正在构建一个脚本，每天自动将我的电子邮件从一个标签移动到下一个标签(这样存储的标记为“5 天”的邮件明天将自动标记为“4 天”，然后“3 天”之后的一天，依此类推)。

问题在于它会将标签应用于整个线程，而不仅仅是消息 - 如果您关闭了对话 View 并且将各种电子邮件分隔在不同的标签下，这就会出现问题。

这是我的脚本(有一个每日触发器):

function moveUp(previousLabel, newLabel) {
  var threads = GmailApp.getUserLabelByName(previousLabel).getThreads()
  var numThreads = threads.length
  if (numThreads>0) {
    for(var i = 0; i < numThreads; i++) {

      if(GmailApp.getUserLabelByName(previousLabel).getThreads().length>0) {
        var lastThread = GmailApp.getUserLabelByName(previousLabel).getThreads()[0]
        GmailApp.getUserLabelByName(newLabel).addToThread(lastThread.markUnread());
        GmailApp.getUserLabelByName(previousLabel).removeFromThread(lastThread)
        Utilities.sleep(200)
      } else {
        {break;}
      }
    }
  }
}

function myFunction() {
  var threads = GmailApp.getUserLabelByName("-To Do/1 Day").getThreads()
  var numThreads = threads.length
  if (numThreads>0) {
    for(var i = 0; i < numThreads; i++) {

      if(GmailApp.getUserLabelByName("-To Do/1 Day").getThreads().length>0) {
        var lastThread = GmailApp.getUserLabelByName("-To Do/1 Day").getThreads()[0]
        lastThread.moveToInbox().markUnread();
        GmailApp.getUserLabelByName("-To Do/1 Day").removeFromThread(lastThread)
        Utilities.sleep(200)
      } else {
        {break;}
      }
    }
  }
    moveUp("-To Do/2 Days", "-To Do/1 Day")
    moveUp("-To Do/3 Days", "-To Do/2 Days")
    moveUp("-To Do/4 Days", "-To Do/3 Days")
    moveUp("-To Do/5 Days", "-To Do/4 Days")
}

那么有人知道如何只将标签应用于特定消息吗？或者实现相同结果的解决方法？

谢谢

Answer 1

您可以使用 GMail API 执行此操作反而。您需要为您的项目启用 API。在编辑器中，选择 Resources > Advanced Google services，然后点击“这些服务也必须在 Google Developers Console 中启用”。在那里，启用 GMail API。

修改消息

使用示例:

modifyMessage('me', messageId, ['stack','overflow']);       // add two labels
modifyMessage('me', messageId, null, ['stack','overflow']); // remove two labels

TL;DR 完整代码可用in this gist , 以及下方隐藏的代码片段。

/**
 * Modify the Labels a Message is associated with.
 * Throws if unsuccessful.
 * see https://developers.google.com/gmail/api/v1/reference/users/messages/modify
 *
 * @param  {String} userId           User's email address. The special value 'me'
 *                                   can be used to indicate the authenticated user.
 * @param  {String} messageId        ID of Message to modify.
 * @param  {String[]} labelsToAdd    Array of Label names to add.
 * @param  {String[]} labelsToRemove Array of Label names to remove.
 *
 * @returns {Object}                 Users.messages resource, see reference. 
 */
function modifyMessage(userId, messageId, labelsToAdd, labelsToRemove) {
  labelsToAdd = labelsToAdd || [];
  labelsToRemove = labelsToRemove || [];
  // see https://developers.google.com/gmail/api/v1/reference/users/messages/modify
  var url = 'https://www.googleapis.com/gmail/v1/users/${userId}/messages/${id}/modify'
            .replace("${userId}","me")
            .replace("${id}", messageId );
  var headers = {
    Authorization: 'Bearer ' + ScriptApp.getOAuthToken()
  };
  var addLabelIds = [];
  for (var i=0; i<labelsToAdd.length; i++) {
    addLabelIds[i] = getLabelId( labelsToAdd[i] );
  }
  var removeLabelIds = [];
  for (var i=0; i<labelsToRemove.length; i++) {
    removeLabelIds[i] = getLabelId( labelsToRemove[i], false );
  }
  var request = {
    'addLabelIds': addLabelIds,
    'removeLabelIds': removeLabelIds
  };
  var params = {
    method: "post",
    contentType: "application/json",
    headers: headers,
    payload: JSON.stringify(request),
    muteHttpExceptions: true
  };
  //var check = UrlFetchApp.getRequest(url, params); // for debugging
  var response = UrlFetchApp.fetch(url, params);

  var result = response.getResponseCode();
  if (result == '200') {  // OK
    return JSON.parse(response.getContentText());
  }
  else {
    // This is only needed when muteHttpExceptions == true
    var err = JSON.parse(response.getContentText());
    throw new Error( 'Error (' + result + ") " + err.error.message );
  }
}

/**
 * Get the Label ID for the given LabelName. If Label isn't found, it will be created
 * depending on the state of ok2Create.
 * Throws if unsuccessful.
 * See https://developers.google.com/gmail/api/v1/reference/users/messages/modify.
 *
 * @param {String}   labelName        Name of label to retrieve ID for.
 * @param {Boolean}  ok2Create        (optional) Set true if a label should be created when not found.
 *                                    Default is true.
 *
 * @returns {String}                  ID of Label, or null if not found or created.
 */
function getLabelId( labelName, ok2Create ) {
  if (typeof ok2Create == 'undefined') ok2Create = true;
  
  var id = null;
  // see https://developers.google.com/gmail/api/v1/reference/users/labels/list
  var url = 'https://www.googleapis.com/gmail/v1/users/${userId}/labels'
            .replace("${userId}","me")  // The user's email address. The special value me can be used to indicate the authenticated user.
  var headers = {
    Authorization: 'Bearer ' + ScriptApp.getOAuthToken()
  };
  var params = {
    method: "get",
    contentType: "application/json",
    headers: headers,
    muteHttpExceptions: true
  };
  
  //var check = UrlFetchApp.getRequest(url, params); // for debugging
  var response = UrlFetchApp.fetch(url, params);

  var result = response.getResponseCode();
  if (result == '200') {  // OK
    var labels = JSON.parse(response.getContentText()).labels;
    var found = false;
    for (var i=0; i<labels.length & !found; i++) {
      if (labels[i].name == labelName) {
        found = true;
        id = labels[i].id;
      }
    }
    if (!found && ok2Create) {
      id = createLabel( labelName );
    }
    return id;
  }
  else {
    // This is only needed when muteHttpExceptions == true
    var err = JSON.parse(response.getContentText());
    throw new Error( 'Error (' + result + ") " + err.error.message );
  }
}

/**
 * Create Label for given `labelName`.
 * Throws if unsuccessful.
 * See https://developers.google.com/gmail/api/v1/reference/users/messages/modify.
 *
 * @param {String}   labelName        Name of label to create
 *
 * @returns {String}                  ID of Label.
 */
function createLabel( labelName ) {
  var id = null;
  // see https://developers.google.com/gmail/api/v1/reference/users/labels/create
  var url = 'https://www.googleapis.com/gmail/v1/users/${userId}/labels'
            .replace("${userId}","me")  // The user's email address. The special value me can be used to indicate the authenticated user.
  var headers = {
    Authorization: 'Bearer ' + ScriptApp.getOAuthToken()
  };
  var request = {
    'name': labelName
  };
  var params = {
    method: "post",
    contentType: "application/json",
    headers: headers,
    payload: JSON.stringify(request),
    muteHttpExceptions: true
  };
  
  //var check = UrlFetchApp.getRequest(url, params); // for debugging
  var response = UrlFetchApp.fetch(url, params);

  var result = response.getResponseCode();
  if (result == '200') {  // OK
    var label = JSON.parse(response.getContentText());
    id = label.id;
    return id;
  }
  else {
    // This is only needed when muteHttpExceptions == true
    var err = JSON.parse(response.getContentText());
    throw new Error( 'Error (' + result + ") " + err.error.message );
  }
}

/**
 * Modify the Labels a Message is associated with.
 * Throws if unsuccessful.
 * see https://developers.google.com/gmail/api/v1/reference/users/messages/modify
 *
 * @param  {String} userId           User's email address. The special value 'me'
 *                                   can be used to indicate the authenticated user.
 * @param  {String} messageId        ID of Message to modify.
 * @param  {String[]} labelsToAdd    Array of Label names to add.
 * @param  {String[]} labelsToRemove Array of Label names to remove.
 *
 * @returns {Object}                 Users.messages resource, see reference. 
 */
function modifyMessage(userId, messageId, labelsToAdd, labelsToRemove) {
  labelsToAdd = labelsToAdd || [];
  labelsToRemove = labelsToRemove || [];
  // see https://developers.google.com/gmail/api/v1/reference/users/messages/modify
  var url = 'https://www.googleapis.com/gmail/v1/users/${userId}/messages/${id}/modify'
            .replace("${userId}","me")
            .replace("${id}", messageId );

GMail API 是一个 RESTful API，与使用内置 GMailApp 服务提供的服务相比，它可以更灵活、更详细地访问线程、消息、标签、草稿和历史记录。在我们的脚本中，我们通过 URL 访问 API - 在这里，我们首先在 modify Message 方法的基本 URL 中填写详细信息。

  var headers = {
    Authorization: 'Bearer ' + ScriptApp.getOAuthToken()
  };

除了为我们的项目启用 API 之外，每个请求都需要用户身份验证，这是通过嵌入 Bearer Token 来完成的。在命令头中。

接下来，我们将构建其余的命令参数。

  var addLabelIds = [];
  for (var i=0; i<labelsToAdd.length; i++) {
    addLabelIds[i] = getLabelId( labelsToAdd[i] );
  }
  var removeLabelIds = [];
  for (i=0; i<labelsToRemove.length; i++) {
    removeLabelIds[i] = getLabelId( labelsToRemove[i], false );
  }
  var request = {
    'addLabelIds': addLabelIds,
    'removeLabelIds': removeLabelIds
  };

modify 的规范调用了一个POST 操作，其负载包含标签 ID 列表。这些 ID 无法通过内置的 GMail 服务获得，因此我们也将为此使用 GMail API - getLabelId() 是另一个与此类似的函数，专门用于检索标签的 ID按名称，并根据需要创建新标签。请参阅该代码的要点或片段。

  var params = {
    method: "post",
    contentType: "application/json",
    headers: headers,
    payload: JSON.stringify(request),
    muteHttpExceptions: true
  };
  //var check = UrlFetchApp.getRequest(url, params); // for debugging
  var response = UrlFetchApp.fetch(url, params);

最后，我们为命令组装了 params 对象，其属性包含带有我们的身份验证 token 的 headers 和带有命令参数，stringify-d 用于传输。设置 muteHttpExceptions: true 会在出现故障时抑制系统生成的异常，以便我们自己处理它们。

我已经注释掉了对 UrlFetchApp.getRequest() 的调用 - 在发送之前验证命令的内容很方便。

对 UrlFetchApp.fetch() 的调用将我们的命令传输到在我们在顶部构建的 URL 上运行的服务。

  var result = response.getResponseCode();
  if (result == '200') {  // OK
    return JSON.parse(response.getContentText());
  }

收到响应后，我们首先检查命令的结果，其格式为HTTP Status Code。 . 200 OK 告诉我们成功了，所以我们继续并从响应中提取结果。 JSON.parse() 转换 JSON string在消息中放入一个 JavaScript 对象，我们将其返回给调用者。

  else {
    // This is only needed when muteHttpExceptions == true
    var err = JSON.parse(response.getContentText());
    throw new Error( 'Error (' + result + ") " + err.error.message );
  }
}

但是，如果遇到错误，我们会抛出自己的异常。根据命令的详细信息，我们可能希望以不同方式处理特定错误。例如，在这个 modify 命令中，如果我们提供一个不存在的标签 ID，我们将收到一个错误:

Error: Error (400) Invalid label: "Invalid-label"