[libvirt] [sandbox PATCH 04/11] Image: Add download function

Refactor download function from virt-sandbox-image to use the newly introduced Source abstract class. The docker-specific download code is moved to a new DockerSource class. --- virt-sandbox-image/sources/DockerSource.py | 193 +++++++++++++++++++++++++++ virt-sandbox-image/sources/Source.py | 5 + virt-sandbox-image/virt-sandbox-image.py | 202 ++++------------------------- 3 files changed, 225 insertions(+), 175 deletions(-) create mode 100644 virt-sandbox-image/sources/DockerSource.py diff --git a/virt-sandbox-image/sources/DockerSource.py b/virt-sandbox-image/sources/DockerSource.py new file mode 100644 index 0000000..5bcd613 --- /dev/null +++ b/virt-sandbox-image/sources/DockerSource.py @@ -0,0 +1,193 @@ +#!/usr/bin/python + +from Source import Source +import urllib2 +import sys +import json +import traceback +import os +import subprocess +import shutil + +class DockerSource(Source): + default_index_server = "index.docker.io" + default_template_dir = "/var/lib/libvirt/templates" + default_image_path = "/var/lib/libvirt/templates" + default_disk_format = "qcow2" + + www_auth_username = None + www_auth_password = None + + def __init__(self,server="index.docker.io",destdir="/var/lib/libvirt/templates"): + self.default_index_server = server + self.default_template_dir = destdir + + def download_template(self,**args): + name = args['name'] + registry = args['registry'] if args['registry'] is not None else self.default_index_server + username = args['username'] + password = args['password'] + templatedir = args['templatedir'] if args['templatedir'] is not None else self.default_template_dir + self.__download_template(name,registry,username,password,templatedir) + + def __download_template(self,name, server,username,password,destdir): + + if username is not None: + self.www_auth_username = username + self.www_auth_password = password + + tag = "latest" + offset = name.find(':') + if offset != -1: + tag = name[offset + 1:] + name = name[0:offset] + try: + (data, res) = self.__get_json(server, "/v1/repositories/" + name + "/images", + {"X-Docker-Token": "true"}) + except urllib2.HTTPError, e: + raise ValueError(["Image '%s' does not exist" % name]) + + registryserver = res.info().getheader('X-Docker-Endpoints') + token = res.info().getheader('X-Docker-Token') + checksums = {} + for layer in data: + pass + (data, res) = self.__get_json(registryserver, "/v1/repositories/" + name + "/tags", + { "Authorization": "Token " + token }) + + cookie = res.info().getheader('Set-Cookie') + + if not tag in data: + raise ValueError(["Tag '%s' does not exist for image '%s'" % (tag, name)]) + imagetagid = data[tag] + + (data, res) = self.__get_json(registryserver, "/v1/images/" + imagetagid + "/ancestry", + { "Authorization": "Token "+token }) + + if data[0] != imagetagid: + raise ValueError(["Expected first layer id '%s' to match image id '%s'", + data[0], imagetagid]) + + try: + createdFiles = [] + createdDirs = [] + + for layerid in data: + templatedir = destdir + "/" + layerid + if not os.path.exists(templatedir): + os.mkdir(templatedir) + createdDirs.append(templatedir) + + jsonfile = templatedir + "/template.json" + datafile = templatedir + "/template.tar.gz" + + if not os.path.exists(jsonfile) or not os.path.exists(datafile): + res = self.__save_data(registryserver, "/v1/images/" + layerid + "/json", + { "Authorization": "Token " + token }, jsonfile) + createdFiles.append(jsonfile) + + layersize = int(res.info().getheader("Content-Length")) + + datacsum = None + if layerid in checksums: + datacsum = checksums[layerid] + + self.__save_data(registryserver, "/v1/images/" + layerid + "/layer", + { "Authorization": "Token "+token }, datafile, datacsum, layersize) + createdFiles.append(datafile) + + index = { + "name": name, + } + + indexfile = destdir + "/" + imagetagid + "/index.json" + print("Index file " + indexfile) + with open(indexfile, "w") as f: + f.write(json.dumps(index)) + except Exception as e: + traceback.print_exc() + for f in createdFiles: + try: + os.remove(f) + except: + pass + for d in createdDirs: + try: + shutil.rmtree(d) + except: + pass + def __save_data(self,server, path, headers, dest, checksum=None, datalen=None): + try: + res = self.__get_url(server, path, headers) + + csum = None + if checksum is not None: + csum = hashlib.sha256() + + pattern = [".", "o", "O", "o"] + patternIndex = 0 + donelen = 0 + + with open(dest, "w") as f: + while 1: + buf = res.read(1024*64) + if not buf: + break + if csum is not None: + csum.update(buf) + f.write(buf) + + if datalen is not None: + donelen = donelen + len(buf) + debug("\x1b[s%s (%5d Kb of %5d Kb)\x1b8" % ( + pattern[patternIndex], (donelen/1024), (datalen/1024) + )) + patternIndex = (patternIndex + 1) % 4 + + debug("\x1b[K") + if csum is not None: + csumstr = "sha256:" + csum.hexdigest() + if csumstr != checksum: + debug("FAIL checksum '%s' does not match '%s'" % (csumstr, checksum)) + os.remove(dest) + raise IOError("Checksum '%s' for data does not match '%s'" % (csumstr, checksum)) + debug("OK\n") + return res + except Exception, e: + debug("FAIL %s\n" % str(e)) + raise + + def __get_url(self,server, path, headers): + url = "https://" + server + path + debug("Fetching %s..." % url) + + req = urllib2.Request(url=url) + if json: + req.add_header("Accept", "application/json") + for h in headers.keys(): + req.add_header(h, headers[h]) + + #www Auth header starts + if self.www_auth_username is not None: + base64string = base64.encodestring('%s:%s' % (self.www_auth_username, self.www_auth_password)).replace('\n', '') + req.add_header("Authorization", "Basic %s" % base64string) + #www Auth header finish + + return urllib2.urlopen(req) + + def __get_json(self,server, path, headers): + try: + res = self.__get_url(server, path, headers) + data = json.loads(res.read()) + debug("OK\n") + return (data, res) + except Exception, e: + debug("FAIL %s\n" % str(e)) + raise + +def debug(msg): + sys.stderr.write(msg) + +if __name__ == "sources.DockerSource": + from __builtin__ import add_hook + add_hook('docker',DockerSource) diff --git a/virt-sandbox-image/sources/Source.py b/virt-sandbox-image/sources/Source.py index cfc75d3..99f44bb 100644 --- a/virt-sandbox-image/sources/Source.py +++ b/virt-sandbox-image/sources/Source.py @@ -6,3 +6,8 @@ class Source(): __metaclass__ = ABCMeta def __init__(self): pass + + @abstractmethod + def download_template(self,**args): + pass + diff --git a/virt-sandbox-image/virt-sandbox-image.py b/virt-sandbox-image/virt-sandbox-image.py index 99ed46e..1392e8f 100644 --- a/virt-sandbox-image/virt-sandbox-image.py +++ b/virt-sandbox-image/virt-sandbox-image.py @@ -40,7 +40,6 @@ verbose = True sys.dont_write_bytecode = True - ##Hook mechanism starts## import __builtin__ from sources.Source import Source @@ -84,178 +83,6 @@ def debug(msg): def info(msg): sys.stdout.write(msg) -def get_url(server, path, headers): - url = "https://" + server + path - debug(" Fetching %s..." % url) - - req = urllib2.Request(url=url) - - if json: - req.add_header("Accept", "application/json") - - for h in headers.keys(): - req.add_header(h, headers[h]) - - return urllib2.urlopen(req) - -def get_json(server, path, headers): - try: - res = get_url(server, path, headers) - data = json.loads(res.read()) - debug("OK\n") - return (data, res) - except Exception, e: - debug("FAIL %s\n" % str(e)) - raise - -def save_data(server, path, headers, dest, checksum=None, datalen=None): - try: - res = get_url(server, path, headers) - - csum = None - if checksum is not None: - csum = hashlib.sha256() - - pattern = [".", "o", "O", "o"] - patternIndex = 0 - donelen = 0 - - with open(dest, "w") as f: - while 1: - buf = res.read(1024*64) - if not buf: - break - if csum is not None: - csum.update(buf) - f.write(buf) - - if datalen is not None: - donelen = donelen + len(buf) - debug("\x1b[s%s (%5d Kb of %5d Kb)\x1b8" % ( - pattern[patternIndex], (donelen/1024), (datalen/1024) - )) - patternIndex = (patternIndex + 1) % 4 - - debug("\x1b[K") - if csum is not None: - csumstr = "sha256:" + csum.hexdigest() - if csumstr != checksum: - debug("FAIL checksum '%s' does not match '%s'" % (csumstr, checksum)) - os.remove(dest) - raise IOError("Checksum '%s' for data does not match '%s'" % (csumstr, checksum)) - - debug("OK\n") - return res - except Exception, e: - debug("FAIL %s\n" % str(e)) - raise - - -def download_template(name, server, destdir): - tag = "latest" - - offset = name.find(':') - if offset != -1: - tag = name[offset + 1:] - name = name[0:offset] - - # First we must ask the index server about the image name. THe - # index server will return an auth token we can use when talking - # to the registry server. We need this token even when anonymous - try: - (data, res) = get_json(server, "/v1/repositories/" + name + "/images", - {"X-Docker-Token": "true"}) - except urllib2.HTTPError, e: - raise ValueError(["Image '%s' does not exist" % name]) - - registryserver = res.info().getheader('X-Docker-Endpoints') - token = res.info().getheader('X-Docker-Token') - checksums = {} - for layer in data: - pass - # XXX Checksums here don't appear to match the data in - # image download later. Find out what these are sums of - #checksums[layer["id"]] = layer["checksum"] - - # Now we ask the registry server for the list of tags associated - # with the image. Tags usually reflect some kind of version of - # the image, but they aren't officially "versions". There is - # always a "latest" tag which is the most recent upload - # - # We must pass in the auth token from the index server. This - # token can only be used once, and we're given a cookie back - # in return to use for later RPC calls. - (data, res) = get_json(registryserver, "/v1/repositories/" + name + "/tags", - { "Authorization": "Token " + token }) - - cookie = res.info().getheader('Set-Cookie') - - if not tag in data: - raise ValueError(["Tag '%s' does not exist for image '%s'" % (tag, name)]) - imagetagid = data[tag] - - # Only base images are self-contained, most images reference one - # or more parents, in a linear stack. Here we are getting the list - # of layers for the image with the tag we used. - (data, res) = get_json(registryserver, "/v1/images/" + imagetagid + "/ancestry", - { "Authorization": "Token " + token }) - - if data[0] != imagetagid: - raise ValueError(["Expected first layer id '%s' to match image id '%s'", - data[0], imagetagid]) - - try: - createdFiles = [] - createdDirs = [] - - for layerid in data: - templatedir = destdir + "/" + layerid - if not os.path.exists(templatedir): - os.mkdir(templatedir) - createdDirs.append(templatedir) - - jsonfile = templatedir + "/template.json" - datafile = templatedir + "/template.tar.gz" - - if not os.path.exists(jsonfile) or not os.path.exists(datafile): - # The '/json' URL gives us some metadata about the layer - res = save_data(registryserver, "/v1/images/" + layerid + "/json", - { "Authorization": "Token " + token }, jsonfile) - createdFiles.append(jsonfile) - layersize = int(res.info().getheader("Content-Length")) - - datacsum = None - if layerid in checksums: - datacsum = checksums[layerid] - - # and the '/layer' URL is the actual payload, provided - # as a tar.gz archive - save_data(registryserver, "/v1/images/" + layerid + "/layer", - { "Authorization": "Token " + token }, datafile, datacsum, layersize) - createdFiles.append(datafile) - - # Strangely the 'json' data for a layer doesn't include - # its actual name, so we save that in a json file of our own - index = { - "name": name, - } - - indexfile = destdir + "/" + imagetagid + "/index.json" - with open(indexfile, "w") as f: - f.write(json.dumps(index)) - except Exception, e: - for f in createdFiles: - try: - os.remove(f) - except: - pass - for d in createdDirs: - try: - os.rmdir(d) - except: - pass - - def delete_template(name, destdir): imageusage = {} imageparent = {} @@ -360,8 +187,16 @@ def create_template(name, imagepath, format, destdir): def download(args): - info("Downloading %s from %s to %s\n" % (args.name, default_index_server, default_template_dir)) - download_template(args.name, default_index_server, default_template_dir) + try: + dynamic_source_loader(args.source).download_template(name=args.name, + registry=args.registry, + username=args.username, + password=args.password, + templatedir=args.template_dir) + except IOError,e: + print "Source %s cannot be found in given path" %args.source + except Exception,e: + print "Download Error %s" % str(e) def delete(args): info("Deleting %s from %s\n" % (args.name, default_template_dir)) @@ -375,10 +210,27 @@ def requires_name(parser): parser.add_argument("name", help=_("name of the template")) +def requires_source(parser): + parser.add_argument("-s","--source", + default="docker", + help=_("name of the template")) + +def requires_auth_conn(parser): + parser.add_argument("-r","--registry", + help=_("Url of the custom registry")) + parser.add_argument("-u","--username", + help=_("Username for the custom registry")) + parser.add_argument("-p","--password", + help=_("Password for the custom registry")) + parser.add_argument("-t","--template-dir", + help=_("Template directory for saving templates")) + def gen_download_args(subparser): parser = subparser.add_parser("download", help=_("Download template data")) + requires_source(parser) requires_name(parser) + requires_auth_conn(parser) parser.set_defaults(func=download) def gen_delete_args(subparser): -- 2.1.0