通过Java ProcessBuilder激活VirtualNV

尝试通过以下代码以编程方式激活Python的virtualenv时，将获得以下信息：

java.io.IOException: Cannot run program "." (in directory "/Users/simeon.../..../reporting"): error=13, Permission denied
    at java.lang.ProcessBuilder.start(ProcessBuilder.java:1048)
    at VirtualEnvCreateCmdTest.runCommandInDirectory(VirtualEnvCreateCmdTest.java:30)
    at VirtualEnvCreateCmdTest.createVirtEnv(VirtualEnvCreateCmdTest.java:61)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at ......
Caused by: java.io.IOException: error=13, Permission denied
    at java.lang.UNIXProcess.forkAndExec(Native Method)
    at java.lang.UNIXProcess.<init>(UNIXProcess.java:247)
    at java.lang.ProcessImpl.start(ProcessImpl.java:134)
    at java.lang.ProcessBuilder.start(ProcessBuilder.java:1029)
    ... 25 more

更改文件的权限似乎不起作用：

chmodu+x./bin/activate

通过

/bin/bash

执行此操作仍然不起作用，但会出现不同的错误

同时，以下命令在命令行上可以正常工作：

. /Users/simeon/.../venv2.7/bin/activate

有没有关于如何从Java中调用python virtualenv activate命令的示例

===什么有效：===

以下内容最终为我工作：

    private void runDjangoMigrate() throws Throwable {

        final String REPORTING_PROJECT_LOCATION = "/Users/simeon.../.../reporting";
        final String UNIX_SHELL_LOCATION = "/bin/bash";
        final String PYTHON_VIRTUALENV_ACTIVATOR_COMMAND =". /Users/simeon.../.../venv2.7/bin/activate;";
        final String PYTHON_VIRTUALENV_ACTIVATOR_COMMAND =". " + PYTHON_VIRTUALENV_ACTIVATE_SCRIPT_LOCATION + ";"; 
        final String DJANGO_MANAGE_MODULE = " manage.py";

        final String[] DJANGO_MIGRATE_COMMAND = new String[] { UNIX_SHELL_LOCATION, "-c", PYTHON_VIRTUALENV_ACTIVATOR_COMMAND
                + PYTHON_INTERPRETER + DJANGO_MANAGE_MODULE + " migrate --noinput --fake-initial" };

        runCommandInDirectory(REPORTING_PROJECT_LOCATION, DJANGO_MIGRATE_COMMAND);


}


    private void runCommandInDirectory(String path, String... command) throws Throwable {

        LOG.info(format("Running '%s' command in path '%s'", join(" ",command),path));

        ProcessBuilder builder = new ProcessBuilder(command).directory(new File(path)).inheritIO();

        Process pr = null;

        pr = builder.start();

        IOUtils.copy(pr.getInputStream(), System.out);  

        boolean terminated = pr.waitFor(SPAWNED_PYTHON_PROCESS_TTL_SEC, SECONDS);

        int exitCode = -1;

        if (terminated) {

            exitCode = pr.exitValue();
        }

        if (exitCode != 0) {

            final String failureMsg = format("Failed to run '%s' in path '%s'.  Got exit code: %d", join(" ", command),
                    path, pr.exitValue());

            throw new Exception(failureMsg);
        }

    }

并产生以下预期产出：

[java] System check identified some issues:
 [java]
 [java] WARNINGS:
 [java] ?: (urls.W005) URL namespace 'admin' isn't unique. You may not be able to reverse all URLs in this namespace
 [java] Building permissions...
 [java] Operations to perform:
 [java]   Apply all migrations: admin, auth, contenttypes, sessions
 [java] Running migrations:
 [java]   No migrations to apply.
 [java] System check identified some issues:
 [java]
 [java] WARNINGS:
 [java] ?: (urls.W005) URL namespace 'admin' isn't unique. You may not be able to reverse all URLs in this namespace
 [java] Building permissions...
 [java] User exists, exiting normally due to --preserve
 [java] System check identified some issues:
 [java]

---

您可以在bash（可能还有zsh）和Python中激活Python虚拟环境，但不能在Java或任何其他环境中激活。需要了解的主要问题是，虚拟环境激活并不会带来一些系统魔法——激活脚本只会更改当前环境，Python虚拟环境只会更改shell或Python，而不会更改其他内容

就Java而言，这意味着当您调用

runCommandInDirectory（）

它运行一个新的shell时，该新shell会短暂地激活一个虚拟环境，但随后shell退出，所有“激活”虚拟环境的更改都消失了

这反过来意味着，如果需要在虚拟环境中运行某些shell或Python命令，则必须在每次

runCommandInDirectory（）

调用中激活环境：

String [] commands1 = new String [] {"/bin/bash", "-c", ". /Users/simeon/..../venv2.7/bin/activate; script1.sh"};
runCommandInDirectory(path, commands)

String [] commands2 = new String [] {"/bin/bash", "-c", ". /Users/simeon/..../venv2.7/bin/activate; script2.sh"};
runCommandInDirectory(path, commands)

对于Python脚本，它稍微简单一些，因为您可以从环境中运行

Python

，并且它会自动激活环境：

String [] commands = new String [] {"/Users/simeon/..../venv2.7/bin/python", "script.py"};
runCommandInDirectory(path, commands)

---

按照您的建议重新安排调用（

String[]commands=new String[]{/bin/bash”、“-c”、“/Users/simeon/…/venv2.7/bin/activate”、“python”、“manage.py”、“migrate”}；

）现在的结果是：

java.lang.IllegalThreadStateException:进程尚未退出。

bash的代码必须是单个字符串：

“/bin/bash”，“-c”，”/Users/simeon/…/venv2.7/bin/activate；python manage.py migrate“

.Else

bash

执行

python

而不带参数，并且

python

进入交互模式。

String [] commands = new String [] {"/Users/simeon/..../venv2.7/bin/python", "script.py"};
runCommandInDirectory(path, commands)