async def http_query(self, method, path, data={}, params={}, timeout=300):
"""
Makes a query to the docker daemon
:param method: HTTP method
:param path: Endpoint in API
:param data: Dictionnary with the body. Will be transformed to a JSON
:param params: Parameters added as a query arg
:param timeout: Timeout
:returns: HTTP response
"""
data = json.dumps(data)
if timeout is None:
timeout = 60 * 60 * 24 * 31 # One month timeout
if path == 'version':
url = "http://docker/v1.12/" + path # API of docker v1.0
else:
url = "http://docker/v" + DOCKER_MINIMUM_API_VERSION + "/" + path
try:
if path != "version": # version is use by check connection
await self._check_connection()
if self._session is None or self._session.closed:
connector = self.connector()
self._session = aiohttp.ClientSession(connector=connector)
response = await self._session.request(method,
url,
params=params,
data=data,
headers={
"content-type":
"application/json",
},
timeout=timeout)
except (aiohttp.ClientResponseError, aiohttp.ClientOSError) as e:
raise DockerError("Docker has returned an error: {}".format(
str(e)))
except (asyncio.TimeoutError):
raise DockerError("Docker timeout " + method + " " + path)
if response.status >= 300:
body = await response.read()
try:
body = json.loads(body.decode("utf-8"))["message"]
except ValueError:
pass
log.debug("Query Docker %s %s params=%s data=%s Response: %s",
method, path, params, data, body)
if response.status == 304:
raise DockerHttp304Error(
"Docker has returned an error: {} {}".format(
response.status, body))
elif response.status == 404:
raise DockerHttp404Error(
"Docker has returned an error: {} {}".format(
response.status, body))
else:
raise DockerError("Docker has returned an error: {} {}".format(
response.status, body))
return response
def connector(self):
if self._connector is None or self._connector.closed:
if not sys.platform.startswith("linux"):
raise DockerError("Docker is supported only on Linux")
try:
self._connector = aiohttp.connector.UnixConnector(
self._server_url, conn_timeout=2, limit=None)
except (aiohttp.errors.ClientOSError, FileNotFoundError):
raise DockerError("Can't connect to docker daemon")
return self._connector
async def pull_image(self, image, progress_callback=None):
"""
Pulls an image from the Docker repository
:params image: Image name
:params progress_callback: A function that receive a log message about image download progress
"""
try:
await self.query("GET", "images/{}/json".format(image))
return # We already have the image skip the download
except DockerHttp404Error:
pass
if progress_callback:
progress_callback("Pulling '{}' from docker hub".format(image))
try:
response = await self.http_query("POST",
"images/create",
params={"fromImage": image},
timeout=None)
except DockerError as e:
raise DockerError(
"Could not pull the '{}' image from Docker Hub, please check your Internet connection (original error: {})"
.format(image, e))
# The pull api will stream status via an HTTP JSON stream
content = ""
while True:
try:
chunk = await response.content.read(CHUNK_SIZE)
except aiohttp.ServerDisconnectedError:
log.error(
"Disconnected from server while pulling Docker image '{}' from docker hub"
.format(image))
break
except asyncio.TimeoutError:
log.error(
"Timeout while pulling Docker image '{}' from docker hub".
format(image))
break
if not chunk:
break
content += chunk.decode("utf-8")
try:
while True:
content = content.lstrip(" \r\n\t")
answer, index = json.JSONDecoder().raw_decode(content)
if "progress" in answer and progress_callback:
progress_callback("Pulling image {}:{}: {}".format(
image, answer["id"], answer["progress"]))
content = content[index:]
except ValueError: # Partial JSON
pass
response.close()
if progress_callback:
progress_callback("Success pulling image {}".format(image))
def _check_connection(self):
if not self._connected:
try:
self._connected = True
connector = self.connector()
version = yield from self.query("GET", "version")
except (aiohttp.errors.ClientOSError, FileNotFoundError):
self._connected = False
raise DockerError("Can't connect to docker daemon")
docker_version = parse_version(version['ApiVersion'])
if docker_version < parse_version(DOCKER_MINIMUM_API_VERSION):
raise DockerError(
"Docker version is {}. GNS3 requires a minimum version of {}"
.format(version["Version"], DOCKER_MINIMUM_VERSION))
preferred_api_version = parse_version(DOCKER_PREFERRED_API_VERSION)
if docker_version >= preferred_api_version:
self._api_version = DOCKER_PREFERRED_API_VERSION
