Question

我最近接手了一个使用Appium进行自动移动测试的项目。我有一些应该与Appium一起运行的python脚本，但是当我尝试运行它们时，我遇到了“[INSTALL_FAILED_VERSION_DOWNGRADE]”。在对此问题进行了大量研究后，我发现这是一个与Android相关的问题，而且是APK版本。但是我是Android的新手，所以这使得完全理解Appium和Android正在做的事情具有挑战性。当我尝试将应用程序安装到设备时，我更倾向于解决问题，但是我觉得我已经解决了解决问题的步骤。一些例子是确保我有最新版本的应用程序，卸载应用程序，重新安装旧版本的应用程序，最后检查更新。

Python脚本追溯：

Appium控制台：

Traceback (most recent call last):
  File "main.py", line 310, in <module>
    launch()
  File "main.py", line 26, in launch
    driver = webdriver.Remote('http://localhost:4723/wd/hub', desired_caps)
  File "C:\Python\lib\site-packages\appium\webdriver\webdriver.py", line 36, in __init__
    super(WebDriver, self).__init__(command_executor, desired_capabilities, browser_profile, proxy, keep_alive)
  File "C:\Python\lib\site-packages\selenium\webdriver\remote\webdriver.py", line 151, in __init__
    self.start_session(desired_capabilities, browser_profile)
  File "C:\Python\lib\site-packages\selenium\webdriver\remote\webdriver.py", line 240, in start_session
    response = self.execute(Command.NEW_SESSION, parameters)
  File "C:\Python\lib\site-packages\selenium\webdriver\remote\webdriver.py", line 308, in execute
    self.error_handler.check_response(response)
  File "C:\Python\lib\site-packages\selenium\webdriver\remote\errorhandler.py", line 194, in check_response
    raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.WebDriverException: Message: A new session could not be created. (Original error: Command failed: C:\AndroidSDK\platform-tools\adb.exe -s GCNPCX031761JAV install "C:\Appium\node_modules\appium\build\settings_apk\settings_apk-debug.apk"
Failed to install C:\Appium\node_modules\appium\build\settings_apk\settings_apk-debug.apk: Failure [INSTALL_FAILED_VERSION_DOWNGRADE]
)

更新：我重新启动计算机并再次运行它，它摆脱了[INSTALL_FAILED_VERSION_DOWNGRADE]，但现在我正在

error: Failed to start an Appium session, err was: Error: Command failed: C:\AndroidSDK\platform-tools\adb.exe -s GCNPCX031761JAV install "C:\Appium\node_modules\appium\build\settings_apk\settings_apk-debug.apk"
Failed to install C:\Appium\node_modules\appium\build\settings_apk\settings_apk-debug.apk: Failure [INSTALL_FAILED_VERSION_DOWNGRADE]

info: [debug] Error: Command failed: C:\AndroidSDK\platform-tools\adb.exe -s GCNPCX031761JAV install "C:\Appium\node_modules\appium\build\settings_apk\settings_apk-debug.apk"
Failed to install C:\Appium\node_modules\appium\build\settings_apk\settings_apk-debug.apk: Failure [INSTALL_FAILED_VERSION_DOWNGRADE]

    at ChildProcess.exithandler (child_process.js:204:12)
    at emitTwo (events.js:106:13)
    at ChildProcess.emit (events.js:191:7)
    at maybeClose (internal/child_process.js:891:16)
    at Process.ChildProcess._handle.onexit (internal/child_process.js:226:5)
info: [debug] Responding to client with error: {"status":33,"value":{"message":"A new session could not be created. (Original error: Command failed: C:\\AndroidSDK\\platform-tools\\adb.exe -s GCNPCX031761JAV install \"C:\\Appium\\node_modules\\appium\\build\\settings_apk\\settings_apk-debug.apk\"\nFailed to install C:\\Appium\\node_modules\\appium\\build\\settings_apk\\settings_apk-debug.apk: Failure [INSTALL_FAILED_VERSION_DOWNGRADE]\r\n)","killed":false,"code":1,"signal":null,"cmd":"C:\\AndroidSDK\\platform-tools\\adb.exe -s GCNPCX031761JAV install \"C:\\Appium\\node_modules\\appium\\build\\settings_apk\\settings_apk-debug.apk\"","origValue":"Command failed: C:\\AndroidSDK\\platform-tools\\adb.exe -s GCNPCX031761JAV install \"C:\\Appium\\node_modules\\appium\\build\\settings_apk\\settings_apk-debug.apk\"\nFailed to install 
C:\\Appium\\node_modules\\appium\\build\\settings_apk\\settings_apk-debug.apk: Failure [INSTALL_FAILED_VERSION_DOWNGRADE]\r\n"},"sessionId":null}

这似乎是ADB的权限问题。

Answer 1

尝试adb install -r -d ${PATH_TO_APK}。

Answer 2

也许app没有正确卸载，请尝试运行命令：

adb shell pm uninstall com.xxx.xxx

将“com.xxx.xxx”替换为您的包裹名称。

Answer 3

您遇到的第一个问题（[INSTALL_FAILED_VERSION_DOWNGRADE]）已在最近的Appium服务器版本 1.7.1 中修复，因此如果您使用的是最新服务器，则无需搜索解决方法。

第二个无法启动Intent的问题更像是您的Android应用manifext.xml文件的问题，您可以检查它是如何修复的here

Answer 4

以防万一，这对任何人都有帮助，我最近收到了此错误Failure [INSTALL_FAILED_VERSION_DOWNGRADE]，这是因为我已经在Android手机上安装了该应用程序，然后将分支切换到了较早的版本号并尝试安装该版本。

简单的解决方案，只需卸载应用程序并重新安装即可。

失败[INSTALL_FAILED_VERSION_DOWNGRADE]

4 个答案: