Python 从命令提示符调用函数

下面是脚本的摘录（未测试）

这些函数在技术上（语法上）正确吗

调用python脚本时如何调用它们？我需要一次启动或停止集群，而不是同时启动或停止

1） 如果您在某个地方定义了

conn

并将其导入，那么它在语法上是正确的

(二)

用法：

   python2.7 test_syn.py fun

---

对于第二个问题，我将通过以下方式解析命令行：

---

我在脚本中添加了一个主函数，用于检查命令行参数，然后在未提供有效参数时提示您：

import sys

def start_custer():
    try:
        myidentifier=mydict['DescribeClustersResponse']['DescribeClustersResult']['Clusters'][0]['ClusterIdentifier']
    except IndexError:
        conn.restore_from_cluster_snapshot('vi-mar5-deliveryreport-new', mysnapidentifier, availability_zone='us-east-1a')

def stop_cluster():
    try:    
        myidentifier=mydict['DescribeClustersResponse']['DescribeClustersResult']['Clusters'][0]['ClusterIdentifier']
        conn.delete_cluster(myidentifier, skip_final_cluster_snapshot=False, final_cluster_snapshot_identifier=myvar)
    except:
        print "error"

def main():
    valid_args, proc = ['start','stop'], None

    # check if cmd line args were passed in (>1 as sys.argv[0] is name of program)
    if len(sys.argv) > 1:
        if sys.argv[1].lower() in valid_args:
            proc = sys.argv[1].lower()

    # if a valid arg was passed in this has been stored in proc, if not prompt user
    while not proc or proc not in valid_args:
        print "\nPlease state which procedure you want to call, valid options are:", valid_args
        proc = raw_input('>>> ').lower()

        # prompt user if invalid
        if proc not in valid_args:
            print proc, 'is not a valid selection.'

    if proc == 'start':
        start_custer()
    elif proc == 'stop':
        stop_cluster()

# this makes the script automatically call main when starting up
if __name__ == '__main__':
    main()

您可以从命令行调用此命令，例如，如果您与文件位于同一目录（例如，名为cluster_ctrl.py），则只需执行以下操作：

---

其他人已经向您展示了执行此操作的最佳方法，但作为记录，您也可以从命令行执行此操作：

python -c "import cluster; cluster.start_cluster()"

（假设您的模块文件名为

cluster.py

——如果不是，则相应地调整

import

语句）

---

这不像自己解析命令行那样方便用户，但在紧要关头就可以了。

好吧，您需要同时捕获

KeyError

和

indexer

。我可以建议您自己测试它吗？这取决于使用的变量。但是，是的，它在语法上似乎是正确的。如果我使用的不是“开始”或“停止”，我就会得到信息。但是为什么我会得到python提示符呢？与>>>类似，如果查看脚本，提示符实际上在

原始输入调用中。这不是真正的Python提示符。@shantanuo正如kindall所说，这不是真正的Python提示符，它只是我碰巧在raw_输入函数中使用的文本。如果您对代码有任何其他问题，请随时询问。
import argparse

parser = argparse.ArgumentParser(description="Manage the cluster")
parser.add_argument("action", choices=["stop", "start"],
                    help="Action to perform")

args = parser.parse_args()
if args.action == "start":
    start_cluster()
if args.action == "stop":
    stop_cluster()

import sys

def start_custer():
    try:
        myidentifier=mydict['DescribeClustersResponse']['DescribeClustersResult']['Clusters'][0]['ClusterIdentifier']
    except IndexError:
        conn.restore_from_cluster_snapshot('vi-mar5-deliveryreport-new', mysnapidentifier, availability_zone='us-east-1a')

def stop_cluster():
    try:    
        myidentifier=mydict['DescribeClustersResponse']['DescribeClustersResult']['Clusters'][0]['ClusterIdentifier']
        conn.delete_cluster(myidentifier, skip_final_cluster_snapshot=False, final_cluster_snapshot_identifier=myvar)
    except:
        print "error"

def main():
    valid_args, proc = ['start','stop'], None

    # check if cmd line args were passed in (>1 as sys.argv[0] is name of program)
    if len(sys.argv) > 1:
        if sys.argv[1].lower() in valid_args:
            proc = sys.argv[1].lower()

    # if a valid arg was passed in this has been stored in proc, if not prompt user
    while not proc or proc not in valid_args:
        print "\nPlease state which procedure you want to call, valid options are:", valid_args
        proc = raw_input('>>> ').lower()

        # prompt user if invalid
        if proc not in valid_args:
            print proc, 'is not a valid selection.'

    if proc == 'start':
        start_custer()
    elif proc == 'stop':
        stop_cluster()

# this makes the script automatically call main when starting up
if __name__ == '__main__':
    main()

python cluster_ctrl.py start

python -c "import cluster; cluster.start_cluster()"