X-Git-Url: https://plomlompom.com/repos/?a=blobdiff_plain;f=plomrogue-server.py;h=8c926526df5dcbc2d1d53b34ab40647a27d31272;hb=f216ec2fd2f4e826e1318691686131afcb5b0c09;hp=f78d12b71a932c4f8b7616ed8e967b41d4971ed9;hpb=4a1ec3a53d32f27ef42b7a2fd49bb96a2c71ea57;p=plomrogue diff --git a/plomrogue-server.py b/plomrogue-server.py index f78d12b..8c92652 100755 --- a/plomrogue-server.py +++ b/plomrogue-server.py @@ -1,52 +1,287 @@ +import argparse import errno import os +import shlex +import shutil import time -def setup_server_io(io_db): +def setup_server_io(): """Fill IO files DB with proper file( path)s. Write process IO test string. - Ensure IO files directory at server/. Remove any old in file if found. Set - up new in file (io_db["file_in"]) for reading at io_db["path_in"], and new - out file (io_db["file_out"]) for writing at io_db["path_out"]. Start out - file with process hash line of format PID + " " + floated UNIX time - (io_db["teststring"]). Set worldstate file path io_db["path_worldstate"]. + Ensure IO files directory at server/. Remove any old input file if found. + Set up new input file for reading, and new output file for writing. Start + output file with process hash line of format PID + " " + floated UNIX time + (io_db["teststring"]). Raise SystemExit if file is found at path of either + record or save file plus io_db["tmp_suffix"]. """ - io_dir = "server/" - io_db["path_in"] = io_dir + "in" - io_db["path_out"] = io_dir + "out" - io_db["path_worldstate"] = io_dir + "worldstate" + def detect_atomic_leftover(path, tmp_suffix): + path_tmp = path + tmp_suffix + msg = "Found file '" + path_tmp + "' that may be a leftover from an " \ + "aborted previous attempt to write '" + path + "'. Aborting " \ + "until matter is resolved by removing it from its current path." + if os.access(path_tmp, os.F_OK): + raise SystemExit(msg) io_db["teststring"] = str(os.getpid()) + " " + str(time.time()) - os.makedirs(io_dir, exist_ok=True) + os.makedirs(io_db["path_server"], exist_ok=True) io_db["file_out"] = open(io_db["path_out"], "w") io_db["file_out"].write(io_db["teststring"] + "\n") + io_db["file_out"].flush() if os.access(io_db["path_in"], os.F_OK): os.remove(io_db["path_in"]) io_db["file_in"] = open(io_db["path_in"], "w") io_db["file_in"].close() io_db["file_in"] = open(io_db["path_in"], "r") + detect_atomic_leftover(io_db["path_save"], io_db["tmp_suffix"]) + detect_atomic_leftover(io_db["path_record"], io_db["tmp_suffix"]) -def cleanup_server_io(io_db): - """Close and remove all files in IO files DB.""" - io_db["file_out"].close() - os.remove(io_db["path_out"]) - io_db["file_in"].close() - os.remove(io_db["path_in"]) - if "file_worldstate" in io_db: # This file's only set up - io_db["file_worldstate"].close() # properly when the game - if os.access(io_db["path_worldstate"], os.F_OK): # world is active, which - os.remove(io_db["path_worldstate"]) # is not guaranteed. +def cleanup_server_io(): + """Close and (if io_db["kicked_by_rival"] false) remove files in io_db.""" + def helper(file_key, path_key): + if file_key in io_db: + io_db[file_key].close() + if not io_db["kicked_by_rival"] \ + and os.access(io_db[path_key], os.F_OK): + os.remove(io_db[path_key]) + helper("file_out", "path_out") + helper("file_in", "path_in") + helper("file_worldstate", "path_worldstate") + if "file_record" in io_db: + io_db["file_record"].close() + + +def obey(command, prefix, replay=False, do_record=False): + """Call function from commands_db mapped to command's first token. + + The command string is tokenized by shlex.split(comments=True). If replay is + set, a non-meta command from the commands_db merely triggers obey() on the + next command from the records file. Non-meta commands are recorded in + non-replay mode if do_record is set. The prefix string is inserted into the + server's input message between its beginning 'input ' and ':'. All activity + is preceded by a call to server_test(). + """ + server_test() + print("input " + prefix + ": " + command) + try: + tokens = shlex.split(command, comments=True) + except ValueError as err: + print("Can't tokenize command string: " + str(err) + ".") + return + if len(tokens) > 0 and tokens[0] in commands_db \ + and len(tokens) >= commands_db[tokens[0]][0] + 1: + if commands_db[tokens[0]][1]: + commands_db[tokens[0]][2]() + elif replay: + print("Due to replay mode, reading command as 'go on in record'.") + line = io_db["file_record"].readline() + if len(line) > 0: + obey(line.rstrip(), io_db["file_record"].prefix + + str(io_db["file_record"].line_n)) + io_db["file_record"].line_n = io_db["file_record"].line_n + 1 + else: + print("Reached end of record file.") + else: + commands_db[tokens[0]][2]() + if do_record: + record(command) + else: + print("Invalid command/argument, or bad number of tokens.") + + +def record(command): + """Append command string plus newline to record file. (Atomic.)""" + # This misses some optimizations from the original record(), namely only + # finishing the atomic write with expensive flush() and fsync() every 15 + # seconds unless explicitely forced. Implement as needed. + path_tmp = io_db["path_record"] + io_db["tmp_suffix"] + if os.access(io_db["path_record"], os.F_OK): + shutil.copyfile(io_db["path_record"], path_tmp) + file = open(path_tmp, "a") + file.write(command + "\n") + file.flush() + os.fsync(file.fileno()) + file.close() + if os.access(io_db["path_record"], os.F_OK): + os.remove(io_db["path_record"]) + os.rename(path_tmp, io_db["path_record"]) + + +def obey_lines_in_file(path, name, do_record=False): + """Call obey() on each line of path's file, use name in input prefix.""" + file = open(path, "r") + line_n = 1 + for line in file.readlines(): + obey(line.rstrip(), name + "file line " + str(line_n), + do_record=do_record) + line_n = line_n + 1 + file.close() + + +def parse_command_line_arguments(): + """Return settings values read from command line arguments.""" + parser = argparse.ArgumentParser() + parser.add_argument('-s', nargs='?', type=int, dest='replay', const=1, + action='store') + opts, unknown = parser.parse_known_args() + return opts + + +def server_test(): + """Ensure valid server out file belonging to current process. + + This is done by comparing io_db["teststring"] to what's found at the start + of the current file at io_db["path_out"]. On failure, set + io_db["kicked_by_rival"] and raise SystemExit. + """ + if not os.access(io_db["path_out"], os.F_OK): + raise SystemExit("Server output file has disappeared.") + file = open(io_db["path_out"], "r") + test = file.readline().rstrip("\n") + file.close() + if test != io_db["teststring"]: + io_db["kicked_by_rival"] = True + msg = "Server test string in server output file does not match. This" \ + " indicates that the current server process has been " \ + "superseded by another one." + raise SystemExit(msg) + + +def read_command(): + """Return next newline-delimited command from server in file. + + Keep building return string until a newline is encountered. Pause between + unsuccessful reads, and after too much waiting, run server_test(). + """ + wait_on_fail = 1 + max_wait = 5 + now = time.time() + command = "" + while True: + add = io_db["file_in"].readline() + if len(add) > 0: + command = command + add + if len(command) > 0 and "\n" == command[-1]: + command = command[:-1] + break + else: + time.sleep(wait_on_fail) + if now + max_wait < time.time(): + server_test() + now = time.time() + return command + + +def replay_game(): + """Replay game from record file. + + Use opts.replay as breakpoint turn to which to replay automatically before + switching to manual input by non-meta commands in server input file + triggering further reads of record file. Ensure opts.replay is at least 1. + """ + if opts.replay < 1: + opts.replay = 1 + print("Replay mode. Auto-replaying up to turn " + str(opts.replay) + + " (if so late a turn is to be found).") + if not os.access(io_db["path_record"], os.F_OK): + raise SystemExit("No record file found to replay.") + io_db["file_record"] = open(io_db["path_record"], "r") + io_db["file_record"].prefix = "recod file line " + io_db["file_record"].line_n = 1 + while world_db["turn"] < opts.replay: + line = io_db["file_record"].readline() + if "" == line: + break + obey(line.rstrip(), io_db["file_record"].prefix + + str(io_db["file_record"].line_n)) + io_db["file_record"].line_n = io_db["file_record"].line_n + 1 + while True: + obey(read_command(), "in file", replay=True) + + +def play_game(): + """Play game by server input file commands. Before, load save file found. + + If no save file is found, a new world is generated from the commands in the + world config plus a 'MAKE WORLD [current Unix timestamp]'. Record this + command and all that follow via the server input file. + """ + if os.access(io_db["path_save"], os.F_OK): + obey_lines_in_file(io_db["path_save"], "save") + else: + if not os.access(io_db["path_worldconf"], os.F_OK): + msg = "No world config file from which to start a new world." + raise SystemExit(msg) + obey_lines_in_file(io_db["path_worldconf"], "world config ", + do_record=True) + obey("MAKE_WORLD " + str(int(time.time())), "in file", do_record=True) + while True: + obey(read_command(), "in file", do_record=True) + + +def command_makeworld(): + """Mere dummy so far.""" + print("I would build a whole world now if only I knew how.") + + +def command_ping(): + """Send PONG line to server output file.""" + io_db["file_out"].write("PONG\n") + io_db["file_out"].flush() + + +def command_quit(): + """Abort server process.""" + raise SystemExit("received QUIT command") + + +"""Commands database. + +Map command start tokens to ([0]) minimum number of expected command arguments, +([1]) the command's meta-ness (i.e. is it to be written to the record file, is +it to be ignored in replay mode if read from server input file), and ([2]) a +function to be called on it. +""" +commands_db = { + "QUIT": (0, True, command_quit), + "PING": (0, True, command_ping), + "MAKE_WORLD": (1, False, command_makeworld) +} + + +"""World state database,""" +world_db = { + "turn": 0 +} + + +"""File IO database.""" +io_db = { + "path_save": "save", + "path_record": "record", + "path_worldconf": "confserver/world", + "path_server": "server/", + "path_in": "server/in", + "path_out": "server/out", + "path_worldstate": "server/worldstate", + "tmp_suffix": "_tmp", + "kicked_by_rival": False +} + -io_db = {} try: - print("DUMMY: Obey command-line arguments.") - print("DUMMY: Open files.") - setup_server_io(io_db) - print("DUMMY: Run game.") + opts = parse_command_line_arguments() + setup_server_io() + # print("DUMMY: Run game.") + if None != opts.replay: + replay_game() + else: + play_game() +except SystemExit as exit: + print("ABORTING: " + exit.args[0]) except: - print("SOMETHING WENT WRONG\n") + print("SOMETHING WENT WRONG IN UNEXPECTED WAYS") raise finally: - cleanup_server_io(io_db) - print("DUMMY: (Clean up C heap.)") + cleanup_server_io() + # print("DUMMY: (Clean up C heap.)")