bin/launch_instance

#!/usr/bin/env python
# Copyright (c) 2009 Chris Moyer http://coredumped.org/
#
# Permission is hereby granted, free of charge, to any person obtaining a
# copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish, dis-
# tribute, sublicense, and/or sell copies of the Software, and to permit
# persons to whom the Software is furnished to do so, subject to the fol-
# lowing conditions:
#
# The above copyright notice and this permission notice shall be included
# in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABIL-
# ITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
# SHALL THE AUTHOR BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, 
# WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS

#
# Utility to launch an EC2 Instance
#
VERSION="0.2"


CLOUD_INIT_SCRIPT = """#!/usr/bin/env python
f = open("/etc/boto.cfg", "w")
f.write(\"\"\"%s\"\"\")
f.close()
"""
import boto.pyami.config
import boto.utils
import re, os
from boto.compat import ConfigParser

class Config(boto.pyami.config.Config):
    """A special config class that also adds import abilities
    Directly in the config file. To have a config file import
    another config file, simply use "#import <path>" where <path>
    is either a relative path or a full URL to another config
    """

    def __init__(self):
        ConfigParser.__init__(self, {'working_dir' : '/mnt/pyami', 'debug' : '0'})

    def add_config(self, file_url):
        """Add a config file to this configuration
        :param file_url: URL for the file to add, or a local path
        :type file_url: str
        """
        if not re.match("^([a-zA-Z0-9]*:\/\/)(.*)", file_url):
            if not file_url.startswith("/"):
                file_url = os.path.join(os.getcwd(), file_url)
            file_url = "file://%s" % file_url
        (base_url, file_name) = file_url.rsplit("/", 1)
        base_config = boto.utils.fetch_file(file_url)
        base_config.seek(0)
        for line in base_config.readlines():
            match = re.match("^#import[\s\t]*([^\s^\t]*)[\s\t]*$", line)
            if match:
                self.add_config("%s/%s" % (base_url, match.group(1)))
        base_config.seek(0)
        self.readfp(base_config)

    def add_creds(self, ec2):
        """Add the credentials to this config if they don't already exist"""
        if not self.has_section('Credentials'):
            self.add_section('Credentials')
            self.set('Credentials', 'aws_access_key_id', ec2.aws_access_key_id)
            self.set('Credentials', 'aws_secret_access_key', ec2.aws_secret_access_key)


    def __str__(self):
        """Get config as string"""
        from StringIO import StringIO
        s = StringIO()
        self.write(s)
        return s.getvalue()

SCRIPTS = []

def scripts_callback(option, opt, value, parser):
    arg = value.split(',')
    if len(arg) == 1:
        SCRIPTS.append(arg[0])
    else:
        SCRIPTS.extend(arg)
    setattr(parser.values, option.dest, SCRIPTS)

def add_script(scr_url):
    """Read a script and any scripts that are added using #import"""
    base_url = '/'.join(scr_url.split('/')[:-1]) + '/'
    script_raw = boto.utils.fetch_file(scr_url)
    script_content = ''
    for line in script_raw.readlines():
        match = re.match("^#import[\s\t]*([^\s^\t]*)[\s\t]*$", line)
        #if there is an import
        if match:
            #Read the other script and put it in that spot
            script_content += add_script("%s/%s" % (base_url, match.group(1)))
        else:
            #Otherwise, add the line and move on
            script_content += line
    return script_content

if __name__ == "__main__":
    try:
        import readline
    except ImportError:
        pass
    import sys
    import time
    import boto
    from boto.ec2 import regions
    from optparse import OptionParser
    from boto.mashups.iobject import IObject
    parser = OptionParser(version=VERSION, usage="%prog [options] config_url")
    parser.add_option("-c", "--max-count", help="Maximum number of this type of instance to launch", dest="max_count", default="1")
    parser.add_option("--min-count", help="Minimum number of this type of instance to launch", dest="min_count", default="1")
    parser.add_option("--cloud-init", help="Indicates that this is an instance that uses 'CloudInit', Ubuntu's cloud bootstrap process. This wraps the config in a shell script command instead of just passing it in directly", dest="cloud_init", default=False, action="store_true")
    parser.add_option("-g", "--groups", help="Security Groups to add this instance to",  action="append", dest="groups")
    parser.add_option("-a", "--ami", help="AMI to launch", dest="ami_id")
    parser.add_option("-t", "--type", help="Type of Instance (default m1.small)", dest="type", default="m1.small")
    parser.add_option("-k", "--key", help="Keypair", dest="key_name")
    parser.add_option("-z", "--zone", help="Zone (default us-east-1a)", dest="zone", default="us-east-1a")
    parser.add_option("-r", "--region", help="Region (default us-east-1)", dest="region", default="us-east-1")
    parser.add_option("-i", "--ip", help="Elastic IP", dest="elastic_ip")
    parser.add_option("-n", "--no-add-cred", help="Don't add a credentials section", default=False, action="store_true", dest="nocred")
    parser.add_option("--save-ebs", help="Save the EBS volume on shutdown, instead of deleting it", default=False, action="store_true", dest="save_ebs")
    parser.add_option("-w", "--wait", help="Wait until instance is running", default=False, action="store_true", dest="wait")
    parser.add_option("-d", "--dns", help="Returns public and private DNS (implicates --wait)", default=False, action="store_true", dest="dns")
    parser.add_option("-T", "--tag", help="Set tag", default=None, action="append", dest="tags", metavar="key:value")
    parser.add_option("-s", "--scripts", help="Pass in a script or a folder containing scripts to be run when the instance starts up, assumes cloud-init. Specify scripts in a list specified by commas. If multiple scripts are specified, they are run lexically (A good way to ensure they run in the order is to prefix filenames with numbers)", type='string', action="callback", callback=scripts_callback)
    parser.add_option("--role", help="IAM Role to use, this implies --no-add-cred", dest="role")

    (options, args) = parser.parse_args()

    if len(args) < 1:
        parser.print_help()
        sys.exit(1)
    file_url = os.path.expanduser(args[0])

    cfg = Config()
    cfg.add_config(file_url)

    for r in regions():
        if r.name == options.region:
            region = r
            break
    else:
        print("Region %s not found." % options.region)
        sys.exit(1)
    ec2 = boto.connect_ec2(region=region)
    if not options.nocred and not options.role:
        cfg.add_creds(ec2)

    iobj = IObject()
    if options.ami_id:
        ami = ec2.get_image(options.ami_id)
    else:
        ami_id = options.ami_id
        l = [(a, a.id, a.location) for a in ec2.get_all_images()]
        ami = iobj.choose_from_list(l, prompt='Choose AMI')

    if options.key_name:
        key_name = options.key_name
    else:
        l = [(k, k.name, '') for k in ec2.get_all_key_pairs()]
        key_name = iobj.choose_from_list(l, prompt='Choose Keypair').name

    if options.groups:
        groups = options.groups
    else:
        groups = []
        l = [(g, g.name, g.description) for g in ec2.get_all_security_groups()]
        g = iobj.choose_from_list(l, prompt='Choose Primary Security Group')
        while g != None:
            groups.append(g)
            l.remove((g, g.name, g.description))
            g = iobj.choose_from_list(l, prompt='Choose Additional Security Group (0 to quit)')

    user_data = str(cfg)
    # If it's a cloud init AMI,
    # then we need to wrap the config in our
    # little wrapper shell script

    if options.cloud_init:
        user_data = CLOUD_INIT_SCRIPT % user_data
        scriptuples = []
        if options.scripts:
            scripts = options.scripts
            scriptuples.append(('user_data', user_data))
            for scr in scripts:
                scr_url = scr
                if not re.match("^([a-zA-Z0-9]*:\/\/)(.*)", scr_url):
                    if not scr_url.startswith("/"):
                        scr_url = os.path.join(os.getcwd(), scr_url)
                    try:
                        newfiles = os.listdir(scr_url)
                        for f in newfiles:
                            #put the scripts in the folder in the array such that they run in the correct order
                            scripts.insert(scripts.index(scr) + 1, scr.split("/")[-1] + "/" + f)
                    except OSError:
                        scr_url = "file://%s" % scr_url
                try:
                    scriptuples.append((scr, add_script(scr_url)))
                except Exception as e:
                    pass

            user_data = boto.utils.write_mime_multipart(scriptuples, compress=True)

    shutdown_proc = "terminate"
    if options.save_ebs:
        shutdown_proc = "save"

    instance_profile_name = None
    if options.role:
        instance_profile_name = options.role

    r = ami.run(min_count=int(options.min_count), max_count=int(options.max_count),
            key_name=key_name, user_data=user_data,
            security_groups=groups, instance_type=options.type,
            placement=options.zone, instance_initiated_shutdown_behavior=shutdown_proc,
            instance_profile_name=instance_profile_name)

    instance = r.instances[0]

    if options.tags:
        for tag_pair in options.tags:
            name = tag_pair
            value = ''
            if ':' in tag_pair:
                name, value = tag_pair.split(':', 1)
            instance.add_tag(name, value)

    if options.dns:
        options.wait = True

    if not options.wait:
        sys.exit(0)

    while True:
        instance.update()
        if instance.state == 'running':
            break
        time.sleep(3)

    if options.dns:
        print("Public DNS name: %s" % instance.public_dns_name)
        print("Private DNS name: %s" % instance.private_dns_name)