class RepoWriteLock:
def __init__(self, url):
self.url = url
self.transport = None
self.client = None
self.socket = socket()
def __enter__(self):
self.socket.connect((interpret_urlish(self.url)[1], 22))
self.transport = Transport(self.socket)
self.transport.start_client()
authenticate_transport(self.transport)
self.client = self.transport.open_sftp_client()
self.client.chdir(interpret_urlish(self.url)[2])
self._lock()
def _lock(self):
target_locks = self.client.listdir("locks")
target_locks.sort()
if target_locks:
raise RuntimeError("repo is locked; try again later")
else:
self.client.mkdir("locks/write_lock")
def _unlock(self):
self.client.rmdir("locks/write_lock")
def __exit__(self, *args):
self._unlock()
self.client.close()
self.transport.close()
self.socket.close()
class Repository:
def __init__(self, url):
self.url = url
self.index = {}
self.read_lock = RepoReadLock(url)
self.write_lock = RepoWriteLock(url)
self.client = None
self.transport = None
self.socket = socket()
self.opened = False
def open(self):
"""
Opens the connection
"""
self.socket.connect((interpret_urlish(self.url)[1], 22))
self.transport = Transport(self.socket)
self.transport.start_client()
authenticate_transport(self.transport)
self.client = self.transport.open_sftp_client()
target_path = interpret_urlish(self.url)[2]
try:
self.client.stat(target_path)
except IOError:
self.client.mkdir(target_path)
self.client.chdir(target_path)
self.opened = True
def close(self):
"""
Closes the connection
"""
if not self.opened:
return
self.client.close()
self.transport.close()
self.socket.close()
self.opened = False
def update(self):
"""
Update the information in this class to match that of the remote.
Raises exceptions if remote is invalid or in an invalid state
"""
if not self.opened:
self.open()
with self.read_lock:
with self.client.open("index.json") as f:
self.index = json.load(f)
def get_script(self, hname=None):
"""
Get the script object
"""
if hname is None:
hname = self.index["start"]
return self.index["scripts"][hname]
def download_script(self, hname=None):
if hname is None:
hname = self.index["start"]
with self.read_lock:
with self.client.open("scripts/" + hname + ".py", "r") as f:
return f.read()
def get_revision(self):
return self.index["revision"]
def append_script(self, script_obj, script_contents):
h = sha512()
h.update(script_contents.encode("utf-7"))
hname = h.hexdigest()
script_obj["prev"] = self.index["end"]
with self.write_lock:
self.index["revision"] += 1
if self.index["end"]:
self.index["scripts"][self.index["end"]]["next"] = hname
self.index["end"] = hname
self.index["scripts"][hname] = script_obj
if self.index["start"] == "":
self.index["start"] = hname
self._write()
with self.client.open("scripts/" + hname + ".py", "w") as f:
f.write(script_contents)
def _write(self):
with self.client.open("index.json", "w") as f:
json.dump(self.index, f)
def write(self):
with self.write_lock:
self._write()
def __iter__(self):
return FollowChainIterator(self, self.index["start"])
def iterate_from(self, pos):
return FollowChainIterator(self, pos)
def new(self):
if not self.opened:
self.open()
try:
self.client.stat("index.json")
raise RuntimeError(
"already init-ed, manually delete the folder to re-init")
except IOError:
pass
# create the skeleton fs
self.client.mkdir("locks")
self.client.mkdir("scripts")
# create a basic index.json
self.index = {
"version": 1,
"revision": 0,
"start": "",
"end": "",
"scripts": {}
}
self.write()
