Question

我正在尝试使用runtime.connectNative和postMessage实现chrome扩展。我正在关注chrome documentation，下载了我正在尝试运行的native messaging example而没有任何更改，同时可以找到本机主机应用程序的代码here。

然而，我收到错误：未捕获的TypeError：无法读取未定义的属性“connectNative”。

错误是从javascript扩展文件触发的，在这一行：
port = chrome.runtime.connectNative（hostName）;

正在从清单加载扩展程序，如下所示：

"app": {
   "launch": {
      "local_path": "main.html"
   }
}

任何想法如何解决问题？

Chrome版本34，在Windows 7,8.1

上测试

Answer 1

当前的问题是您没有正确运行示例代码。更大的问题是Google没有提供有关如何使用此示例代码的全面文档。

您引用的Native Messaging示例仅链接到Chrome扩展程序的示例代码。在搜索之后，我能够找到本机消息传递主机应用程序的相关示例代码。要同时获取Chrome扩展程序和本机消息传递主机应用程序的示例代码，您需要下载nativeMessaging.zip。在该zip文件中，您还可以找到有关如何在Windows，Linux和Mac OS X上安装本机消息传递主机的简要说明。我现在会告诉您说明不完整，因为它们没有告诉您如何安装Chrome扩展程序。此外，用于安装和卸载本机消息传递主机的脚本在OS X上不能正常工作。请参阅下面的安装说明和更正的脚本。

如何安装示例扩展和本机主机应用程序

下载并解压缩nativeMessaging.zip文件。
安装Chrome扩展程序
1. 在Chrome中，在地址栏中输入chrome://extensions/
2. 点击“加载解压后的扩展程序...”按钮
3. 导航到解压缩的nativeMessaging目录并选择要导入的app目录
安装本机消息传递主机应用程序
1. 对于OS X和Linux，您需要为某些文件添加执行权限。运行命令：chmod a+rx nativeMessaging/host/install_host.sh nativeMessaging/host/native-messaging-example-host nativeMessaging/host/uninstall_host.sh
2. 对于OS X，您需要修复nativeMessaging/host/install_host.sh和nativeMessaging/host/uninstall_host.sh中的一些错误。请参阅下面的更正脚本。
3. 对于OS X，Linux和Windows，请按照nativeMessaging/README.txt
运行Chrome扩展程序
1. 在Chrome中，在地址栏中输入chrome://apps/
2. 单击Native Messaging Example应用程序图标
3. 应用程序加载后，您应该会看到一个名为“Connect”的按钮。单击该按钮，您将看到自动启动本机消息传递主机应用程序。

已更正nativeMessaging/host/install_host.sh

#!/bin/sh
# Copyright 2013 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

set -e

DIR="$( cd "$( dirname "$0" )" && pwd )"
if [ $(uname -s) == 'Darwin' ]; then
  if [ "$(whoami)" == "root" ]; then
    TARGET_DIR="/Library/Google/Chrome/NativeMessagingHosts"
  else
    TARGET_DIR="$HOME/Library/Application Support/Google/Chrome/NativeMessagingHosts"
  fi
else
  if [ "$(whoami)" == "root" ]; then
    TARGET_DIR="/etc/opt/chrome/native-messaging-hosts"
  else
    TARGET_DIR="$HOME/.config/google-chrome/NativeMessagingHosts"
  fi
fi

HOST_NAME=com.google.chrome.example.echo

# Create directory to store native messaging host.
mkdir -p "$TARGET_DIR"

# Copy native messaging host manifest.
cp "$DIR/$HOST_NAME.json" "$TARGET_DIR"

# Update host path in the manifest.
HOST_PATH="$DIR/native-messaging-example-host"
ESCAPED_HOST_PATH=${HOST_PATH////\\/}
sed -i -e "s/HOST_PATH/$ESCAPED_HOST_PATH/" "$TARGET_DIR/$HOST_NAME.json"

# Set permissions for the manifest so that all users can read it.
chmod o+r "$TARGET_DIR/$HOST_NAME.json"

echo Native messaging host $HOST_NAME has been installed.

已更正nativeMessaging/host/uninstall_host.sh

#!/bin/sh
# Copyright 2013 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

set -e

if [ $(uname -s) == 'Darwin' ]; then
  if [ "$(whoami)" == "root" ]; then
    TARGET_DIR="/Library/Google/Chrome/NativeMessagingHosts"
  else
    TARGET_DIR="$HOME/Library/Application Support/Google/Chrome/NativeMessagingHosts"
  fi
else
  if [ "$(whoami)" == "root" ]; then
    TARGET_DIR="/etc/opt/chrome/native-messaging-hosts"
  else
    TARGET_DIR="$HOME/.config/google-chrome/NativeMessagingHosts"
  fi
fi

HOST_NAME=com.google.chrome.example.echo
rm "$TARGET_DIR/com.google.chrome.example.echo.json"
echo Native messaging host $HOST_NAME has been uninstalled.

Answer 2

我想提供脚本的python 3版本来替换 native-messaging-example-host 。它已经过Chrome v86的测试，可以正常工作。请注意，关闭tkinter窗口时python内核崩溃-这是因为 threading 内部的二进制数据交换导致线程被硬锁定（更多信息here）。我添加了一个命令 exit 从chrome应用程序发送，以停止线程等待另一个标准输入。收到它后，python不会在退出时崩溃。

Python 3版本（已通过3.7.4测试）：

# A simple native messaging host. Shows a Tkinter dialog with incoming messages
# that also allows to send message back to the webapp.

import struct
import sys
import threading
import queue as Queue

try:
  import tkinter as Tkinter
  import tkinter.messagebox
except ImportError:
  Tkinter = None

# On Windows, the default I/O mode is O_TEXT. Set this to O_BINARY
# to avoid unwanted modifications of the input/output streams.
if sys.platform == "win32":
  import os, msvcrt
  msvcrt.setmode(sys.stdin.fileno(), os.O_BINARY)
  msvcrt.setmode(sys.stdout.fileno(), os.O_BINARY)

# Helper function that sends a message to the webapp.
def send_message(message):
   # Write message size.
  sys.stdout.buffer.write(struct.pack('I', len(message)))
  # Write the message itself.
  sys.stdout.write(message)
  sys.stdout.flush()

# Thread that reads messages from the webapp.
def read_thread_func(queue):
  message_number = 0
  while 1:
    # Read the message length (first 4 bytes).
    text_length_bytes = sys.stdin.buffer.read(4)

    if len(text_length_bytes) == 0:
      if queue:
        queue.put(None)
      sys.exit(0)

    # Unpack message length as 4 byte integer.
    text_length = struct.unpack('@I', text_length_bytes)[0]

    # Read the text (JSON object) of the message.
    text = sys.stdin.buffer.read(text_length).decode('utf-8')

    if text == '{"text":"exit"}':
      break

    if queue:
      queue.put(text)
    else:
      # In headless mode just send an echo message back.
      send_message('{"echo": %s}' % text)

if Tkinter:
  class NativeMessagingWindow(tkinter.Frame):
    def __init__(self, queue):
      self.queue = queue

      tkinter.Frame.__init__(self)
      self.pack()

      self.text = tkinter.Text(self)
      self.text.grid(row=0, column=0, padx=10, pady=10, columnspan=2)
      self.text.config(state=tkinter.DISABLED, height=10, width=40)

      self.messageContent = tkinter.StringVar()
      self.sendEntry = tkinter.Entry(self, textvariable=self.messageContent)
      self.sendEntry.grid(row=1, column=0, padx=10, pady=10)

      self.sendButton = tkinter.Button(self, text="Send", command=self.onSend)
      self.sendButton.grid(row=1, column=1, padx=10, pady=10)

      self.after(100, self.processMessages)

    def processMessages(self):
      while not self.queue.empty():
        message = self.queue.get_nowait()
        if message == None:
          self.quit()
          return
        self.log("Received %s" % message)

      self.after(100, self.processMessages)

    def onSend(self):
      text = '{"text": "' + self.messageContent.get() + '"}'
      self.log('Sending %s' % text)
      try:
        send_message(text)
      except IOError:
        tkinter.messagebox.showinfo('Native Messaging Example',
                              'Failed to send message.')
        sys.exit(1)

    def log(self, message):
      self.text.config(state=tkinter.NORMAL)
      self.text.insert(tkinter.END, message + "\n")
      self.text.config(state=tkinter.DISABLED)


def Main():
  if not Tkinter:
    send_message('"Tkinter python module wasn\'t found. Running in headless ' +
                 'mode. Please consider installing Tkinter."')
    read_thread_func(None)
    sys.exit(0)

  queue = Queue.Queue()

  main_window = NativeMessagingWindow(queue)
  main_window.master.title('Native Messaging Example')

  thread = threading.Thread(target=read_thread_func, args=(queue,))
  thread.daemon = True
  thread.start()

  main_window.mainloop()

  sys.exit(0)


if __name__ == '__main__':
  Main()

免责声明：我使用2to3实用程序将其初始转换为python3。我还采用了nativeMessage API示例的webextensions（firefox）版本的更改（它经过简化，没有使用tkinter gui）

Chrome扩展程序NativeMessaging＆＃39; connectNative＆＃39;未定义

2 个答案: