Enter text

class Log:
def __init__(self, path):
dirname = os.path.dirname(path)
os.makedirs(dirname, exist_ok=True)
f = open(path, "a+")

# Check that the file is newline-terminated
size = os.path.getsize(path)
if size > 0:
f.seek(size - 1)
end = f.read(1)
if end != "\n":
f.write("\n")
self.f = f
self.path = path

def log(self, event):
event["_event_id"] = str(uuid.uuid4())
json.dump(event, self.f)
self.f.write("\n")

def state(self):
state = {"complete": set(), "last": None}
for line in open(self.path):
event = json.loads(line)
if event["type"] == "submit" and event["success"]:
state["complete"].add(event["id"])
state["last"] = event
return state

"""
Here's what the above class is doing:
1. The constructor creates a directory for the log file if it doesn't exist.
2. The log() method writes a JSON-encoded event to the log file.
3. The state() method returns a dictionary with the set of complete tasks and the most recent event.