434 lines
		
	
	
		
			14 KiB
		
	
	
	
		
			Python
		
	
	
			
		
		
	
	
			434 lines
		
	
	
		
			14 KiB
		
	
	
	
		
			Python
		
	
	
# -*- coding: utf-8 -*-
 | 
						|
# Copyright 2014 - 2016 OpenMarket Ltd
 | 
						|
# Copyright 2018 New Vector Ltd
 | 
						|
#
 | 
						|
# 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.
 | 
						|
 | 
						|
import fnmatch
 | 
						|
import imp
 | 
						|
import logging
 | 
						|
import os
 | 
						|
import re
 | 
						|
 | 
						|
 | 
						|
logger = logging.getLogger(__name__)
 | 
						|
 | 
						|
 | 
						|
# Remember to update this number every time a change is made to database
 | 
						|
# schema files, so the users will be informed on server restarts.
 | 
						|
SCHEMA_VERSION = 50
 | 
						|
 | 
						|
dir_path = os.path.abspath(os.path.dirname(__file__))
 | 
						|
 | 
						|
 | 
						|
class PrepareDatabaseException(Exception):
 | 
						|
    pass
 | 
						|
 | 
						|
 | 
						|
class UpgradeDatabaseException(PrepareDatabaseException):
 | 
						|
    pass
 | 
						|
 | 
						|
 | 
						|
def prepare_database(db_conn, database_engine, config):
 | 
						|
    """Prepares a database for usage. Will either create all necessary tables
 | 
						|
    or upgrade from an older schema version.
 | 
						|
 | 
						|
    If `config` is None then prepare_database will assert that no upgrade is
 | 
						|
    necessary, *or* will create a fresh database if the database is empty.
 | 
						|
 | 
						|
    Args:
 | 
						|
        db_conn:
 | 
						|
        database_engine:
 | 
						|
        config (synapse.config.homeserver.HomeServerConfig|None):
 | 
						|
            application config, or None if we are connecting to an existing
 | 
						|
            database which we expect to be configured already
 | 
						|
    """
 | 
						|
    try:
 | 
						|
        cur = db_conn.cursor()
 | 
						|
        version_info = _get_or_create_schema_state(cur, database_engine)
 | 
						|
 | 
						|
        if version_info:
 | 
						|
            user_version, delta_files, upgraded = version_info
 | 
						|
 | 
						|
            if config is None:
 | 
						|
                if user_version != SCHEMA_VERSION:
 | 
						|
                    # If we don't pass in a config file then we are expecting to
 | 
						|
                    # have already upgraded the DB.
 | 
						|
                    raise UpgradeDatabaseException("Database needs to be upgraded")
 | 
						|
            else:
 | 
						|
                _upgrade_existing_database(
 | 
						|
                    cur, user_version, delta_files, upgraded, database_engine, config
 | 
						|
                )
 | 
						|
        else:
 | 
						|
            _setup_new_database(cur, database_engine)
 | 
						|
 | 
						|
        # check if any of our configured dynamic modules want a database
 | 
						|
        if config is not None:
 | 
						|
            _apply_module_schemas(cur, database_engine, config)
 | 
						|
 | 
						|
        cur.close()
 | 
						|
        db_conn.commit()
 | 
						|
    except Exception:
 | 
						|
        db_conn.rollback()
 | 
						|
        raise
 | 
						|
 | 
						|
 | 
						|
def _setup_new_database(cur, database_engine):
 | 
						|
    """Sets up the database by finding a base set of "full schemas" and then
 | 
						|
    applying any necessary deltas.
 | 
						|
 | 
						|
    The "full_schemas" directory has subdirectories named after versions. This
 | 
						|
    function searches for the highest version less than or equal to
 | 
						|
    `SCHEMA_VERSION` and executes all .sql files in that directory.
 | 
						|
 | 
						|
    The function will then apply all deltas for all versions after the base
 | 
						|
    version.
 | 
						|
 | 
						|
    Example directory structure:
 | 
						|
 | 
						|
        schema/
 | 
						|
            delta/
 | 
						|
                ...
 | 
						|
            full_schemas/
 | 
						|
                3/
 | 
						|
                    test.sql
 | 
						|
                    ...
 | 
						|
                11/
 | 
						|
                    foo.sql
 | 
						|
                    bar.sql
 | 
						|
                ...
 | 
						|
 | 
						|
    In the example foo.sql and bar.sql would be run, and then any delta files
 | 
						|
    for versions strictly greater than 11.
 | 
						|
    """
 | 
						|
    current_dir = os.path.join(dir_path, "schema", "full_schemas")
 | 
						|
    directory_entries = os.listdir(current_dir)
 | 
						|
 | 
						|
    valid_dirs = []
 | 
						|
    pattern = re.compile(r"^\d+(\.sql)?$")
 | 
						|
    for filename in directory_entries:
 | 
						|
        match = pattern.match(filename)
 | 
						|
        abs_path = os.path.join(current_dir, filename)
 | 
						|
        if match and os.path.isdir(abs_path):
 | 
						|
            ver = int(match.group(0))
 | 
						|
            if ver <= SCHEMA_VERSION:
 | 
						|
                valid_dirs.append((ver, abs_path))
 | 
						|
        else:
 | 
						|
            logger.warn("Unexpected entry in 'full_schemas': %s", filename)
 | 
						|
 | 
						|
    if not valid_dirs:
 | 
						|
        raise PrepareDatabaseException(
 | 
						|
            "Could not find a suitable base set of full schemas"
 | 
						|
        )
 | 
						|
 | 
						|
    max_current_ver, sql_dir = max(valid_dirs, key=lambda x: x[0])
 | 
						|
 | 
						|
    logger.debug("Initialising schema v%d", max_current_ver)
 | 
						|
 | 
						|
    directory_entries = os.listdir(sql_dir)
 | 
						|
 | 
						|
    for filename in fnmatch.filter(directory_entries, "*.sql"):
 | 
						|
        sql_loc = os.path.join(sql_dir, filename)
 | 
						|
        logger.debug("Applying schema %s", sql_loc)
 | 
						|
        executescript(cur, sql_loc)
 | 
						|
 | 
						|
    cur.execute(
 | 
						|
        database_engine.convert_param_style(
 | 
						|
            "INSERT INTO schema_version (version, upgraded)"
 | 
						|
            " VALUES (?,?)"
 | 
						|
        ),
 | 
						|
        (max_current_ver, False,)
 | 
						|
    )
 | 
						|
 | 
						|
    _upgrade_existing_database(
 | 
						|
        cur,
 | 
						|
        current_version=max_current_ver,
 | 
						|
        applied_delta_files=[],
 | 
						|
        upgraded=False,
 | 
						|
        database_engine=database_engine,
 | 
						|
        config=None,
 | 
						|
        is_empty=True,
 | 
						|
    )
 | 
						|
 | 
						|
 | 
						|
def _upgrade_existing_database(cur, current_version, applied_delta_files,
 | 
						|
                               upgraded, database_engine, config, is_empty=False):
 | 
						|
    """Upgrades an existing database.
 | 
						|
 | 
						|
    Delta files can either be SQL stored in *.sql files, or python modules
 | 
						|
    in *.py.
 | 
						|
 | 
						|
    There can be multiple delta files per version. Synapse will keep track of
 | 
						|
    which delta files have been applied, and will apply any that haven't been
 | 
						|
    even if there has been no version bump. This is useful for development
 | 
						|
    where orthogonal schema changes may happen on separate branches.
 | 
						|
 | 
						|
    Different delta files for the same version *must* be orthogonal and give
 | 
						|
    the same result when applied in any order. No guarantees are made on the
 | 
						|
    order of execution of these scripts.
 | 
						|
 | 
						|
    This is a no-op of current_version == SCHEMA_VERSION.
 | 
						|
 | 
						|
    Example directory structure:
 | 
						|
 | 
						|
        schema/
 | 
						|
            delta/
 | 
						|
                11/
 | 
						|
                    foo.sql
 | 
						|
                    ...
 | 
						|
                12/
 | 
						|
                    foo.sql
 | 
						|
                    bar.py
 | 
						|
                ...
 | 
						|
            full_schemas/
 | 
						|
                ...
 | 
						|
 | 
						|
    In the example, if current_version is 11, then foo.sql will be run if and
 | 
						|
    only if `upgraded` is True. Then `foo.sql` and `bar.py` would be run in
 | 
						|
    some arbitrary order.
 | 
						|
 | 
						|
    Args:
 | 
						|
        cur (Cursor)
 | 
						|
        current_version (int): The current version of the schema.
 | 
						|
        applied_delta_files (list): A list of deltas that have already been
 | 
						|
            applied.
 | 
						|
        upgraded (bool): Whether the current version was generated by having
 | 
						|
            applied deltas or from full schema file. If `True` the function
 | 
						|
            will never apply delta files for the given `current_version`, since
 | 
						|
            the current_version wasn't generated by applying those delta files.
 | 
						|
    """
 | 
						|
 | 
						|
    if current_version > SCHEMA_VERSION:
 | 
						|
        raise ValueError(
 | 
						|
            "Cannot use this database as it is too " +
 | 
						|
            "new for the server to understand"
 | 
						|
        )
 | 
						|
 | 
						|
    start_ver = current_version
 | 
						|
    if not upgraded:
 | 
						|
        start_ver += 1
 | 
						|
 | 
						|
    logger.debug("applied_delta_files: %s", applied_delta_files)
 | 
						|
 | 
						|
    for v in range(start_ver, SCHEMA_VERSION + 1):
 | 
						|
        logger.info("Upgrading schema to v%d", v)
 | 
						|
 | 
						|
        delta_dir = os.path.join(dir_path, "schema", "delta", str(v))
 | 
						|
 | 
						|
        try:
 | 
						|
            directory_entries = os.listdir(delta_dir)
 | 
						|
        except OSError:
 | 
						|
            logger.exception("Could not open delta dir for version %d", v)
 | 
						|
            raise UpgradeDatabaseException(
 | 
						|
                "Could not open delta dir for version %d" % (v,)
 | 
						|
            )
 | 
						|
 | 
						|
        directory_entries.sort()
 | 
						|
        for file_name in directory_entries:
 | 
						|
            relative_path = os.path.join(str(v), file_name)
 | 
						|
            logger.debug("Found file: %s", relative_path)
 | 
						|
            if relative_path in applied_delta_files:
 | 
						|
                continue
 | 
						|
 | 
						|
            absolute_path = os.path.join(
 | 
						|
                dir_path, "schema", "delta", relative_path,
 | 
						|
            )
 | 
						|
            root_name, ext = os.path.splitext(file_name)
 | 
						|
            if ext == ".py":
 | 
						|
                # This is a python upgrade module. We need to import into some
 | 
						|
                # package and then execute its `run_upgrade` function.
 | 
						|
                module_name = "synapse.storage.v%d_%s" % (
 | 
						|
                    v, root_name
 | 
						|
                )
 | 
						|
                with open(absolute_path) as python_file:
 | 
						|
                    module = imp.load_source(
 | 
						|
                        module_name, absolute_path, python_file
 | 
						|
                    )
 | 
						|
                logger.info("Running script %s", relative_path)
 | 
						|
                module.run_create(cur, database_engine)
 | 
						|
                if not is_empty:
 | 
						|
                    module.run_upgrade(cur, database_engine, config=config)
 | 
						|
            elif ext == ".pyc":
 | 
						|
                # Sometimes .pyc files turn up anyway even though we've
 | 
						|
                # disabled their generation; e.g. from distribution package
 | 
						|
                # installers. Silently skip it
 | 
						|
                pass
 | 
						|
            elif ext == ".sql":
 | 
						|
                # A plain old .sql file, just read and execute it
 | 
						|
                logger.info("Applying schema %s", relative_path)
 | 
						|
                executescript(cur, absolute_path)
 | 
						|
            else:
 | 
						|
                # Not a valid delta file.
 | 
						|
                logger.warn(
 | 
						|
                    "Found directory entry that did not end in .py or"
 | 
						|
                    " .sql: %s",
 | 
						|
                    relative_path,
 | 
						|
                )
 | 
						|
                continue
 | 
						|
 | 
						|
            # Mark as done.
 | 
						|
            cur.execute(
 | 
						|
                database_engine.convert_param_style(
 | 
						|
                    "INSERT INTO applied_schema_deltas (version, file)"
 | 
						|
                    " VALUES (?,?)",
 | 
						|
                ),
 | 
						|
                (v, relative_path)
 | 
						|
            )
 | 
						|
 | 
						|
            cur.execute("DELETE FROM schema_version")
 | 
						|
            cur.execute(
 | 
						|
                database_engine.convert_param_style(
 | 
						|
                    "INSERT INTO schema_version (version, upgraded)"
 | 
						|
                    " VALUES (?,?)",
 | 
						|
                ),
 | 
						|
                (v, True)
 | 
						|
            )
 | 
						|
 | 
						|
 | 
						|
def _apply_module_schemas(txn, database_engine, config):
 | 
						|
    """Apply the module schemas for the dynamic modules, if any
 | 
						|
 | 
						|
    Args:
 | 
						|
        cur: database cursor
 | 
						|
        database_engine: synapse database engine class
 | 
						|
        config (synapse.config.homeserver.HomeServerConfig):
 | 
						|
            application config
 | 
						|
    """
 | 
						|
    for (mod, _config) in config.password_providers:
 | 
						|
        if not hasattr(mod, 'get_db_schema_files'):
 | 
						|
            continue
 | 
						|
        modname = ".".join((mod.__module__, mod.__name__))
 | 
						|
        _apply_module_schema_files(
 | 
						|
            txn, database_engine, modname, mod.get_db_schema_files(),
 | 
						|
        )
 | 
						|
 | 
						|
 | 
						|
def _apply_module_schema_files(cur, database_engine, modname, names_and_streams):
 | 
						|
    """Apply the module schemas for a single module
 | 
						|
 | 
						|
    Args:
 | 
						|
        cur: database cursor
 | 
						|
        database_engine: synapse database engine class
 | 
						|
        modname (str): fully qualified name of the module
 | 
						|
        names_and_streams (Iterable[(str, file)]): the names and streams of
 | 
						|
            schemas to be applied
 | 
						|
    """
 | 
						|
    cur.execute(
 | 
						|
        database_engine.convert_param_style(
 | 
						|
            "SELECT file FROM applied_module_schemas WHERE module_name = ?"
 | 
						|
        ),
 | 
						|
        (modname,)
 | 
						|
    )
 | 
						|
    applied_deltas = set(d for d, in cur)
 | 
						|
    for (name, stream) in names_and_streams:
 | 
						|
        if name in applied_deltas:
 | 
						|
            continue
 | 
						|
 | 
						|
        root_name, ext = os.path.splitext(name)
 | 
						|
        if ext != '.sql':
 | 
						|
            raise PrepareDatabaseException(
 | 
						|
                "only .sql files are currently supported for module schemas",
 | 
						|
            )
 | 
						|
 | 
						|
        logger.info("applying schema %s for %s", name, modname)
 | 
						|
        for statement in get_statements(stream):
 | 
						|
            cur.execute(statement)
 | 
						|
 | 
						|
        # Mark as done.
 | 
						|
        cur.execute(
 | 
						|
            database_engine.convert_param_style(
 | 
						|
                "INSERT INTO applied_module_schemas (module_name, file)"
 | 
						|
                " VALUES (?,?)",
 | 
						|
            ),
 | 
						|
            (modname, name)
 | 
						|
        )
 | 
						|
 | 
						|
 | 
						|
def get_statements(f):
 | 
						|
    statement_buffer = ""
 | 
						|
    in_comment = False  # If we're in a /* ... */ style comment
 | 
						|
 | 
						|
    for line in f:
 | 
						|
        line = line.strip()
 | 
						|
 | 
						|
        if in_comment:
 | 
						|
            # Check if this line contains an end to the comment
 | 
						|
            comments = line.split("*/", 1)
 | 
						|
            if len(comments) == 1:
 | 
						|
                continue
 | 
						|
            line = comments[1]
 | 
						|
            in_comment = False
 | 
						|
 | 
						|
        # Remove inline block comments
 | 
						|
        line = re.sub(r"/\*.*\*/", " ", line)
 | 
						|
 | 
						|
        # Does this line start a comment?
 | 
						|
        comments = line.split("/*", 1)
 | 
						|
        if len(comments) > 1:
 | 
						|
            line = comments[0]
 | 
						|
            in_comment = True
 | 
						|
 | 
						|
        # Deal with line comments
 | 
						|
        line = line.split("--", 1)[0]
 | 
						|
        line = line.split("//", 1)[0]
 | 
						|
 | 
						|
        # Find *all* semicolons. We need to treat first and last entry
 | 
						|
        # specially.
 | 
						|
        statements = line.split(";")
 | 
						|
 | 
						|
        # We must prepend statement_buffer to the first statement
 | 
						|
        first_statement = "%s %s" % (
 | 
						|
            statement_buffer.strip(),
 | 
						|
            statements[0].strip()
 | 
						|
        )
 | 
						|
        statements[0] = first_statement
 | 
						|
 | 
						|
        # Every entry, except the last, is a full statement
 | 
						|
        for statement in statements[:-1]:
 | 
						|
            yield statement.strip()
 | 
						|
 | 
						|
        # The last entry did *not* end in a semicolon, so we store it for the
 | 
						|
        # next semicolon we find
 | 
						|
        statement_buffer = statements[-1].strip()
 | 
						|
 | 
						|
 | 
						|
def executescript(txn, schema_path):
 | 
						|
    with open(schema_path, 'r') as f:
 | 
						|
        for statement in get_statements(f):
 | 
						|
            txn.execute(statement)
 | 
						|
 | 
						|
 | 
						|
def _get_or_create_schema_state(txn, database_engine):
 | 
						|
    # Bluntly try creating the schema_version tables.
 | 
						|
    schema_path = os.path.join(
 | 
						|
        dir_path, "schema", "schema_version.sql",
 | 
						|
    )
 | 
						|
    executescript(txn, schema_path)
 | 
						|
 | 
						|
    txn.execute("SELECT version, upgraded FROM schema_version")
 | 
						|
    row = txn.fetchone()
 | 
						|
    current_version = int(row[0]) if row else None
 | 
						|
    upgraded = bool(row[1]) if row else None
 | 
						|
 | 
						|
    if current_version:
 | 
						|
        txn.execute(
 | 
						|
            database_engine.convert_param_style(
 | 
						|
                "SELECT file FROM applied_schema_deltas WHERE version >= ?"
 | 
						|
            ),
 | 
						|
            (current_version,)
 | 
						|
        )
 | 
						|
        applied_deltas = [d for d, in txn]
 | 
						|
        return current_version, applied_deltas, upgraded
 | 
						|
 | 
						|
    return None
 |