First release

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 jCloud Third-Party Notices
 ===========================
 This software uses the following third-party libraries. Full license texts are available in the 'licenses/' directory.
 1. config-parser 1.2.1
   Author: jCloud Services GbR
   License: Apache License 2.0
   See licenses/config-parser.txt for full license text.
 2. jeb-utils 0.1.4
   Author: jCloud Services GbR
   License: Apache License 2.0
   See licenses/jeb-utils.txt for full license text.
@@ -0,0 +1,35 @@
 # jeb-server-utils
 The utilities for the jeb server
 ## Installation
 You can install the library using `pip`:
 ```bash
 pip install jeb-server-utils --index-url https://repo.jcloud-services.ddns.net/simple/
 ```
 ## Usage
 ### `JEBServerUtils`
 The main class. It has following methods:
 - `get_segment_base_timestamp`: Returns the base timestamp of a segment.
 - `get_topics`: Returns all topics.
 - `mktopic`: Creates a topic.
 - `rmtopic`: Removes a topic.
 - `mktopicpart`: Creates a partition of a topic.
 - `rmtopicpart`: Removes a partition of a topic.
 - `check_topic_exists`: Checks whether a topic exists (raises an exception if not).
 - `create_record`: Creates a record.
 - `fetch_records`: Fetches records from the topic and yields them in chunks.
 ### `Topic`
 A topic.
 ### `Segment`:
 A segment.
 For more details, see the function and method docstrings.
 ## Changelog
 ### Version 0.1.0
 - First release
@@ -0,0 +1,215 @@
 Copyright 2026 jCloud Services GbR
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
 You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
 Unless required by applicable law or agreed to in writing, software
 distributed under the License is distributed on an "AS IS" BASIS,
 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.
                                 Apache License
                           Version 2.0, January 2004
                        http://www.apache.org/licenses/
   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
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@@ -0,0 +1,215 @@
 Copyright 2026 jCloud Services GbR
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
 You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
 Unless required by applicable law or agreed to in writing, software
 distributed under the License is distributed on an "AS IS" BASIS,
 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.
                                 Apache License
                           Version 2.0, January 2004
                        http://www.apache.org/licenses/
   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
   1. Definitions.
      "License" shall mean the terms and conditions for use, reproduction,
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      names, trademarks, service marks, or product names of the Licensor,
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   APPENDIX: How to apply the Apache License to your work.
      To apply the Apache License to your work, attach the following
      boilerplate notice, with the fields enclosed by brackets "[]"
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   Copyright [yyyy] [name of copyright owner]
   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at
       http://www.apache.org/licenses/LICENSE-2.0
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   limitations under the License.
@@ -0,0 +1,10 @@
 [build-system]
 requires = ["setuptools", "wheel"]
 build-backend = "setuptools.build_meta"
 [project]
 name = "jeb-server-utils"
 version = "0.1.0"
 description = "The utilities for the jeb server"
 dependencies = ["config-parser", "jeb-utils"]
 license = "Apache-2.0"
@@ -0,0 +1,24 @@
 #  Copyright 2026 jCloud Services GbR
 #
 #  Licensed under the Apache License, Version 2.0 (the "License");
 #  you may not use this file except in compliance with the License.
 #  You may obtain a copy of the License at
 #
 #      https://www.apache.org/licenses/LICENSE-2.0
 #
 #  Unless required by applicable law or agreed to in writing, software
 #  distributed under the License is distributed on an "AS IS" BASIS,
 #  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 #  See the License for the specific language governing permissions and
 #  limitations under the License.
 '''
 The utilities for the jeb server
 '''
 from _core import *
 from _core import __all__ as _core__all__
 __all__ = [
    *_core__all__
 ]
@@ -0,0 +1,510 @@
 #  Copyright 2026 jCloud Services GbR
 #
 #  Licensed under the Apache License, Version 2.0 (the "License");
 #  you may not use this file except in compliance with the License.
 #  You may obtain a copy of the License at
 #
 #      https://www.apache.org/licenses/LICENSE-2.0
 #
 #  Unless required by applicable law or agreed to in writing, software
 #  distributed under the License is distributed on an "AS IS" BASIS,
 #  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 #  See the License for the specific language governing permissions and
 #  limitations under the License.
 from jeb_utils import exceptions, jeb_utils, utils
 import os
 import dbm
 import config_parser
 import shutil
 import time
 import binascii
 import warnings
 __all__ = [
    'JEBServerUtils',
    'Segment',
    'Topic',
 ]
 def _create_file_if_not_exists(path: str, content: bytes = b''):
    '''
    Creates a file if it does not exist.
    :param path: The file path
    :type path: str
    :param content: Optional, the content of the file if it is newly created.
    :type content: bytes
    '''
    if not os.path.exists(path):
        with open(path, 'wb') as f:
            f.write(content)
            f.close()
 class JEBServerUtils:
    def __init__(self, data_dir: str, *, segment_max_size: int = 2 ** 32, fetch_records_chunk_size: int = 1024 ** 2):
        '''
        The utilities for the jeb server.
        '''
        self.data_dir = data_dir
        self.segment_max_size = segment_max_size
        self.fetch_records_chunk_size = fetch_records_chunk_size
        self._log_end_offsets = {}
        self._init()
    def _init(self):
        self._create_base_segment_files()
        self._init_log_end_offsets()
    def _create_base_segment_files(self):
        '''
        Creates the base segment files.
        '''
        for topic, v in self.get_topics().items():
            partitions = jeb_utils.format_topic_partitions(topic, v['partitions'])
            for p in partitions:
                _create_file_if_not_exists(f'{self.data_dir}/topics/{p}/' + '0' * 16 + '.log')
                _create_file_if_not_exists(f'{self.data_dir}/topics/{p}/' + '0' * 16 + '.index')
                _create_file_if_not_exists(f'{self.data_dir}/topics/{p}/' + '0' * 16 + '.timeindex')
    def _init_log_end_offsets(self):
        '''
        Initializes the log end offsets.
        '''
        global _log_end_offsets
        topics = [f'{t}{jeb_utils.TOPIC_PARTITION_SEPARATOR}{p:02d}' for t, v in self.get_topics().items() for p in v['partitions']]
        topic_segments = {t: Topic(t, self).segments for t in topics}
        for topic, segments in topic_segments.items():
            log_end_offset = 0
            for segment in segments:
                with open(f'{self.data_dir}/topics/{topic}/{segment.base_offset:016x}.log', 'rb') as logfile:
                    logfile.seek(0, os.SEEK_END)
                    file_size = logfile.tell()
                    logfile.seek(0)
                    while True:
                        record_size_bytes = logfile.read(8)
                        if not record_size_bytes or len(record_size_bytes) < 8:
                            break
                        record_size = int.from_bytes(record_size_bytes)
                        if logfile.tell() + record_size > file_size:
                            break
                        logfile.seek(record_size, os.SEEK_CUR)
                        log_end_offset += 1
                    logfile.close()
            self._log_end_offsets[topic] = log_end_offset
    def get_segment_base_timestamp(self, topic: str, segment: int) -> int:
        '''
        Returns the base timestamp of a segment.
        :param topic: The topic
        :type topic: str
        :param segment: The segment base offset
        :type segment: int
        :return: The base timestamp (milliseconds since 1970)
        :rtype: int
        '''
        with open(f'{self.data_dir}/topics/{topic}/{segment:016x}.log', 'rb') as logfile:
            # go to the topic length
            logfile.seek(20)
            # skip topic
            topic_length = int.from_bytes(logfile.read(2))
            logfile.seek(topic_length + 1, os.SEEK_CUR)
            timestamp_bytes = logfile.read(8)
            if len(timestamp_bytes) < 8:
                timestamp = None
            else:
                timestamp = int.from_bytes(timestamp_bytes)
        return timestamp
    def get_topics(self):
        '''
        Returns all topics.
        :return: The topics
        :rtype: dict
        '''
        with dbm.open(f'{self.data_dir}/conf/topics', 'c') as db:
            topics = {k.decode(): config_parser.parse.json.parse_json(v.decode()) for k, v in db.items()}
            db.close()
        return topics
    def mktopic(self, topic_name: str):
        '''
        Creates a topic.
        :param topic_name: The name of the topic
        :type topic_name: str
        '''
        with dbm.open(f'{self.data_dir}/conf/topics', 'c') as db:
            if topic_name.encode() in db.keys():
                raise exceptions.TopicExistsError(f'topic \'{topic_name}\' already exists')
            db[topic_name] = config_parser.serialize.json.serialize({'partitions': [1]})
            db.close()
        os.mkdir(f'{self.data_dir}/topics/{topic_name}{jeb_utils.TOPIC_PARTITION_SEPARATOR}01/')
    def rmtopic(self, topic_name: str):
        '''
        Removes a topic.
        :param topic_name: The topic name
        :type topic_name: str
        :raises TopicNotFoundError: If the topic does not exist.
        '''
        with dbm.open(f'{self.data_dir}/conf/topics', 'c') as db:
            if topic_name.encode() not in db.keys():
                raise exceptions.TopicNotFoundError(f'topic \'{topic_name}\' does not exist')
            partitions = config_parser.parse.json.parse_json(db[topic_name.encode()].decode())['partitions']
            del db[topic_name]
            db.close()
        partition_dirs = jeb_utils.format_topic_partitions(topic_name, partitions)
        for pd in partition_dirs:
            try:
                shutil.rmtree(f'{self.data_dir}/topics/{pd}/')
            except:
                pass
    def mktopicpart(self, topic_name: str, partition_number: int):
        '''
        Creates a partition of a topic.
        :param topic_name: The topic name
        :type topic_name: str
        :param partition_number: The partition number
        :type partition_number: int
        '''
        if partition_number < 1 or partition_number > 99:
            raise ValueError('partition number must be between 1 and 99')
        formatted_partition_number = f'{(int(partition_number)):02d}'
        with dbm.open(f'{self.data_dir}/conf/topics', 'c') as db:
            if topic_name.encode() not in db.keys():
                raise exceptions.TopicNotFoundError(f'topic \'{topic_name}\' does not exist')
            partitions = config_parser.parse.json.parse_json(db[topic_name.encode()].decode())['partitions']
            if partition_number in partitions:
                raise exceptions.TopicPartitionExistsError(f'partition \'{formatted_partition_number}\' already exists for topic \'{topic_name}\'')
            db[topic_name] = config_parser.serialize.json.serialize({'partitions': sorted(list(set(partitions) | {int(formatted_partition_number)}))})
            db.close()
        os.mkdir(f'{self.data_dir}/topics/{topic_name}{jeb_utils.TOPIC_PARTITION_SEPARATOR}{formatted_partition_number}/')
    def rmtopicpart(self, topic_name: str, partition_number: int):
        '''
        Removes a partition of a topic.
        :param topic_name: The topic name
        :type topic_name: str
        :param partition_number: The partition number
        :type partition_number: int
        '''
        formatted_partition_number = f'{(int(partition_number)):02d}'
        with dbm.open(f'{self.data_dir}/conf/topics', 'c') as db:
            if topic_name.encode() not in db.keys():
                raise exceptions.TopicNotFoundError(f'topic \'{topic_name}\' does not exist')
            partitions = config_parser.parse.json.parse_json(db[topic_name.encode()].decode())['partitions']
            if partition_number not in partitions:
                raise exceptions.TopicPartitionNotFoundError(f'partition \'{formatted_partition_number}\' does not exist for topic \'{topic_name}\'')
            db[topic_name] = config_parser.serialize.json.serialize({'partitions': sorted(list(set(partitions) - {int(formatted_partition_number)}))})
            db.close()
        shutil.rmtree(f'{self.data_dir}/topics/{topic_name}{jeb_utils.TOPIC_PARTITION_SEPARATOR}{formatted_partition_number}/')
    def check_topic_exists(self, topic: str):
        '''
        Checks whether a topic exists.
        :param topic: The topic name
        :type topic: str
        :raises TopicNotFoundError: If the topic does not exist
        :raises TopicPartitionNotFoundError: If the partition does not exist
        '''
        topics = self.get_topics()
        topic_name, formatted_partition_number = topic.split(jeb_utils.TOPIC_PARTITION_SEPARATOR)
        raw_partition_number = int(formatted_partition_number)
        if topic_name not in topics:
            raise exceptions.TopicNotFoundError(f'topic \'{topic_name}\' does not exist')
        if raw_partition_number not in topics[topic_name]['partitions']:
            raise exceptions.TopicPartitionNotFoundError(f'partition \'{formatted_partition_number}\' does not exist for topic \'{topic_name}\'')
    def create_record(self, topic: str, timestamp: int, record_data: bytes, key: bytes = b'', compression_type: int = 0, headers: dict = {}):
        '''
        Creates a record.
        :param topic: The topic name
        :type topic: str
        :param timestamp: The timestamp.
        :type timestamp: int
        :param record_data: The payload
        :type record_data: bytes
        :param key: The key
        :type key: bytes
        :param compression_type: The compression type
        :type compression_type: int
        :param headers: The header dictionary
        :type headers: dict
        '''
        topic_name, formatted_partition_number = topic.split(jeb_utils.TOPIC_PARTITION_SEPARATOR)
        if not jeb_utils.validate_topic_name(topic_name):
            raise exceptions.FormatError(f'invalid topic name: \'{topic}\'')
        self.check_topic_exists(topic)
        topic_dir = f'{self.data_dir}/topics/{topic_name}{jeb_utils.TOPIC_PARTITION_SEPARATOR}{formatted_partition_number}/'
        utils.create_file_if_not_exists(topic_dir + '0' * 16 + '.log')
        segments = sorted([int(f.split('.')[0], 16) for f in os.listdir(topic_dir) if f.endswith('.log') and utils.is_number(f.split('.')[0], 16) and len(f.split('.')[0]) == 16])
        last_segment = max(segments)
        if timestamp == 0:
            timestamp = int(time.time() * 1000)
            timestamp_type = 1
        else:
            timestamp_type = 0
        # Assemble record
        record = b''
        record += self._log_end_offsets[topic].to_bytes(8)  # Offset
        record += binascii.crc32(record_data).to_bytes(4)  # CRC
        record += (len(topic)).to_bytes(2)  # Topic name length
        record += topic.encode()  # Topic
        record += jeb_utils.AttributesByte(compression_type, timestamp_type).to_byte() # Attributes
        record += timestamp.to_bytes(8)  # Timestamp
        record += (len(key)).to_bytes(4)  # Key Length
        record += key  # Key
        record += (len(record_data)).to_bytes(4)  # Content Length
        record += record_data  # Content
        record += (len(headers)).to_bytes(1)
        for key, value in headers.items():
            record += len(key).to_bytes(4)
            record += key
            record += len(value).to_bytes(4)
            record += value
        record = len(record).to_bytes(8) + record  # Prepend Record Size
        if os.path.getsize(topic_dir + f'{last_segment:016x}.log') + len(record) > self.segment_max_size:
            last_segment = self._log_end_offsets[topic]
        with open(topic_dir + f'{last_segment:016x}.log', 'ab') as logfile:
            logfile.write(record)
            logfile.close()
        utils.create_file_if_not_exists(topic_dir + f'{last_segment:016x}.index')
        utils.create_file_if_not_exists(topic_dir + f'{last_segment:016x}.timeindex')
        if self._log_end_offsets[topic] % 1024 == 0:
            index = self._log_end_offsets[topic].to_bytes(8) + os.path.getsize(topic_dir + f'{last_segment:016x}.log').to_bytes(4)
            timeindex = timestamp.to_bytes(8) + self._log_end_offsets[topic].to_bytes(8)
            with open(topic_dir + f'{last_segment:016x}.index', 'ab') as idxfile:
                idxfile.write(index)
                idxfile.close()
            with open(topic_dir + f'{last_segment:016x}.timeindex', 'ab') as timeidxfile:
                timeidxfile.write(timeindex)
                timeidxfile.close()
        self._log_end_offsets[topic] += 1
    def fetch_records(self, topic: str, start_type: int, start: int, max_bytes: int):
        '''
        Fetches records from the topic and yields them in chunks.
        :param topic: The topic name
        :type topic: str
        :param start_type: The start type
        :type start_type: int
        :param start: The start
        :type start: int
        :param max_bytes: The maximum of bytes
        :type max_bytes: int
        '''
        topic = Topic(topic, self)
        topic_name, formatted_partition_number = topic.topic_name.split(jeb_utils.TOPIC_PARTITION_SEPARATOR)
        if not jeb_utils.validate_topic_name(topic_name):
            raise exceptions.FormatError(f'invalid topic name: \'{topic.topic_name}\'')
        if start_type not in (jeb_utils.FETCH_START_TYPE_OFFSET, jeb_utils.FETCH_START_TYPE_TIMESTAMP):
            raise ValueError('invalid start type')
        self.check_topic_exists(topic.topic_name)
        segments = [int(f.split('.')[0], 16) for f in os.listdir(f'{self.data_dir}/topics/{topic.topic_name}/') if utils.is_number(f.split('.')[0], 16) and len(f.split('.')[0]) == 16 and f.endswith('.log')]
        if start_type == jeb_utils.FETCH_START_TYPE_TIMESTAMP:
            segment_base_timestamps = {s: s.base_timestamp for s in topic.segments}
            s = {v: k for k, v in segment_base_timestamps.items()}[utils.find_nearest_lower_number(list(segment_base_timestamps.values()), start) or min(segment_base_timestamps.values())]
            with open(f'{self.data_dir}/topics/{topic.topic_name}/{s.base_offset:016x}.timeindex', 'rb') as f:
                timestamps = {}
                f.seek(0)
                while True:
                    timestamp_bytes = f.read(8)
                    if len(timestamp_bytes) < 8:
                        break
                    timestamp = int.from_bytes(timestamp_bytes)
                    offset_bytes = f.read(8)
                    if len(offset_bytes) < 8:
                        break
                    offset = int.from_bytes(offset_bytes)
                    timestamps[timestamp] = offset
                f.close()
            start = timestamps[utils.find_nearest_lower_number(timestamps.keys(), start) or min(timestamps.keys())]
        if start < 0 or start >= self._log_end_offsets[topic.topic_name]:
            # await send_block_function(b'\xb1\x31')
            yield b'\xb1\x31'
            return
        idx_offset = jeb_utils.get_next_lower_index_entry(start)
        start_seg = utils.find_nearest_lower_number(segments, start)
        with open(f'{self.data_dir}/topics/{topic.topic_name}/' + f'{start_seg:016x}' + '.index', 'rb') as idxfile:
            idxfile.seek(0, os.SEEK_END)
            file_size = idxfile.tell()
            idxfile.seek(idx_offset // 1024 * 12)
            index_entry = idxfile.read(12)
            idx_entry_pos = int.from_bytes(index_entry[8:])
            if int.from_bytes(index_entry[:8]) != idx_offset:
                warnings.warn(f'Index entry offset mismatch: expected {idx_offset}, got {int.from_bytes(index_entry[:8])}', jeb_utils.FileCorruptWarning)
            idxfile.close()
        with open(f'{self.data_dir}/topics/{topic.topic_name}/{start_seg:016x}.log', 'rb') as logfile:
            logfile.seek(idx_entry_pos)
            offset = idx_offset
            record_position = 0
            while offset < start:
                record_length_bytes = logfile.read(8)
                if len(record_length_bytes) < 8:
                    break
                record_length = int.from_bytes(record_length_bytes)
                offset_bytes = logfile.read(8)
                if len(offset_bytes) < 8:
                    break            
                offset = int.from_bytes(offset_bytes)
                record_position = logfile.tell() - 16
                logfile.seek(record_length - 8, os.SEEK_CUR)
            logfile.close()
        # await send_block_function(b'\xa0\x30')
        yield b'\xa0\x30'
        segments = sorted(segments)
        bytes_fetched = 0
        for i, segment in enumerate(segments[segments.index(start_seg):]):
            records_sent = 0
            with open(f'{self.data_dir}/topics/{topic.topic_name}/' + f'{segment:016x}' + '.log', 'rb') as logfile:
                if i == 0:
                    logfile.seek(record_position)
                else:
                    logfile.seek(0)
                while bytes_fetched <= max_bytes:
                    record_size_bytes = logfile.read(8)
                    if len(record_size_bytes) < 8:
                        break
                    record_size = int.from_bytes(record_size_bytes)
                    if bytes_fetched + 8 + record_size > max_bytes:
                        break
                    to_send = record_size_bytes
                    for _ in range(record_size // jeb_utils.FETCH_RECORDS_CHUNK_SIZE):
                        to_send += logfile.read(jeb_utils.FETCH_RECORDS_CHUNK_SIZE)
                        # await send_block_function(b'\x01' + to_send)
                        yield b'\x01' + to_send
                        to_send = b''
                    to_send += logfile.read(record_size % jeb_utils.FETCH_RECORDS_CHUNK_SIZE)
                    # await send_block_function(b'\x01' + to_send)
                    yield b'\x01' + to_send
                    bytes_fetched += 8 + record_size
                    records_sent += 1
                logfile.close()
            if bytes_fetched >= max_bytes:
                break
        # await send_block_function(b'\x00') # EOF
        yield b'\x00' # EOF
 class Segment:
    def __init__(self, topic: str, base_offset: int, jeb_server_utils: JEBServerUtils):
        '''
        Represents a segment of a topic.
        :param topic: The topic name
        :type topic: str
        :param base_offset: The base offset of the segment
        :type base_offset: int
        :param jeb_server_utils: The ``JEBServerUtils`` instance
        :type jeb_server_utils: JEBServerUtils
        '''
        self.topic = topic
        self.base_offset = base_offset
        self.jeb_server_utils = jeb_server_utils
        self.base_timestamp = self.get_base_timestamp()
    def __repr__(self):
        return f'Segment({self.topic}, {self.base_offset})'
    def get_base_timestamp(self):
        '''
        Returns the base timestamp of the segment.
        :return: The base timestamp (milliseconds since 1970)
        :rtype: int
        '''
        # with open(f'{self.jeb_server_utils.data_dir}/topics/{self.topic}/{self.base_offset:016x}.timeindex', 'rb') as logfile:
        #     timestamp_bytes = logfile.read(8)
        #     if len(timestamp_bytes) < 8:
        #         timestamp = None
        #     else:
        #         timestamp = int.from_bytes(timestamp_bytes)
        # return timestamp
        return self.jeb_server_utils.get_segment_base_timestamp(self.topic, self.base_offset)
 class Topic:
    def __init__(self, topic_name: str, jeb_server_utils: JEBServerUtils):
        '''
        Represents a topic.
        :param topic_name: The name of the topic
        :type topic_name: str
        :param jeb_server_utils: The ``JEBServerUtils`` instance
        :type jeb_server_utils: JEBServerUtils
        '''
        self.topic_name = topic_name
        self.jeb_server_utils = jeb_server_utils
    def __repr__(self):
        return f'Topic({self.topic_name})'
    @property
    def segments(self):
        '''
        Returns the segments of the topic.
        :return: The segments
        :rtype: list
        '''
        return [Segment(self.topic_name, bo, self.jeb_server_utils) for bo in sorted([int(s.split('.')[0], 16) for s in os.listdir(f'{self.jeb_server_utils.data_dir}/topics/{self.topic_name}') if s.endswith('.log') and utils.is_number(s.split('.')[0], 16) and len(s.split('.')[0]) == 16])]