| #!/usr/bin/env python3 |
| # |
| # Copyright (c) Greenplum Inc 2009. All Rights Reserved. |
| # |
| # |
| # NOTE: The file semantics here are subtle. In this file, we are reading or writing to filename, which is |
| # presumed to be a postgresql.conf format file. When reading a file, we read that file in a single open(file) call |
| # When writing a file, we read that file, and write the new file contents to a temporary file created securely. |
| # Then, we use os.rename() to overwrite that existing file. These rules allow us to either get the OLD file or the |
| # NEW file in any subsequent operation. This is because os.rename() POSIX requires does not overwrite the existing |
| # file but swaps the inodes of the files, so the os.rename() does NOT affect any current readers who have already |
| # opened the OLD file. |
| |
| try: |
| import os |
| import shutil |
| import sys |
| import tempfile |
| import base64 |
| import pickle |
| |
| from optparse import Option, OptionParser |
| from gppylib.gpparseopts import OptParser, OptChecker |
| except ImportError as e: |
| sys.exit('Cannot import modules. Please check that you have sourced cloudberry-env.sh. Detail: ' + str(e)) |
| |
| _help = ["""This enables one to add, get and remove postgresql.conf configuration parameters. |
| The absolute path to the postgresql.conf file is required."""] |
| |
| |
| def parseargs(): |
| parser = OptParser(option_class=OptChecker) |
| |
| parser.setHelp(_help) |
| |
| parser.remove_option('-h') |
| parser.add_option('-h', '-?', '--help', action='help', help='show this help message and exit') |
| |
| parser.add_option('--file', type='string', help='Required: The absolute path of postgresql.conf') |
| parser.add_option('--add-parameter', type='string', help='The configuration parameter to add. --value is required.') |
| parser.add_option('--value', type='string', help='The configuration value to add when using --add-parameter.') |
| parser.add_option('--get-parameter', type='string', help='The configuration parameter value to return.') |
| parser.add_option('--remove-parameter', type='string', help='The configuration parameter value to disable.') |
| |
| (options, args) = parser.parse_args() |
| return validate_args(options) |
| |
| |
| def validate_args(options): |
| if not options.file: |
| sys.stderr.write("--file required") |
| sys.exit(1) |
| |
| if options.add_parameter and not options.value: |
| sys.stderr.write("Missing --value <value> when adding parameter '%s'." % options.add_parameter) |
| sys.exit(1) |
| |
| if (options.get_parameter or options.remove_parameter) and options.value: |
| sys.stderr.write("Cannot specify --value when using --get-parameter or --remove-parameter") |
| sys.exit(1) |
| |
| if (options.add_parameter and options.get_parameter) or \ |
| (options.add_parameter and options.remove_parameter) or \ |
| (options.get_parameter and options.remove_parameter): |
| sys.stderr.write("Can only specify one of --add-parameter, --get-parameter, or --remove-parameter") |
| sys.exit(1) |
| |
| return options |
| |
| |
| def _read_from_file_and_get_empty_tempfile(filename): |
| with open(filename, 'r') as infile: |
| lines = infile.readlines() |
| |
| # TODO: does this work in the case of temp_conf_file containing spaces? |
| (tempFD, temp_conf_path) = tempfile.mkstemp(prefix="postgresql_", suffix=".conf", dir=os.path.abspath(os.path.dirname(filename))) |
| os.close(tempFD) |
| os.chmod(os.path.abspath(temp_conf_path), os.stat(os.path.abspath(filename)).st_mode) |
| return lines, temp_conf_path |
| |
| |
| def comment_parameter(filename, name): |
| lines, temp_conf_path = _read_from_file_and_get_empty_tempfile(filename) |
| |
| new_lines = 0 |
| with open(os.path.abspath(temp_conf_path), 'w') as outfile: |
| for line in lines: |
| potential_match = line.split("=", 1)[0] |
| if potential_match.strip() == name: |
| outfile.write('#') |
| outfile.write(line) |
| new_lines = new_lines + 1 |
| |
| if new_lines == len(lines): |
| os.rename(os.path.abspath(temp_conf_path), filename) |
| |
| |
| def add_parameter(filename, name, value): |
| lines, temp_conf_path = _read_from_file_and_get_empty_tempfile(filename) |
| |
| new_lines = 0 |
| with open(os.path.abspath(temp_conf_path), 'w') as outfile: |
| for line in lines: |
| outfile.write(line) |
| new_lines = new_lines + 1 |
| outfile.write(name + '=' + pickle.loads(base64.urlsafe_b64decode(value)) + os.linesep) |
| new_lines = new_lines + 1 |
| |
| if new_lines == len(lines) + 1: |
| os.rename(os.path.abspath(temp_conf_path), filename) |
| |
| |
| # NOTE: though apparently not documented, postgresQL returns the last valid value |
| def get_parameter(filename, name): |
| with open(filename, 'r') as f: |
| for line in reversed(f.readlines()): |
| parts = line.split("=", 1) |
| if len(parts) > 1 and parts[0].lstrip().startswith(name): |
| return parts[1].strip() |
| |
| |
| def main(): |
| options = parseargs() |
| if options.get_parameter: |
| try: |
| value = get_parameter(options.file, options.get_parameter) |
| sys.stdout.write(base64.urlsafe_b64encode(pickle.dumps(value)).decode()) |
| return |
| except Exception as err: |
| sys.stderr.write("Failed to get value for parameter '%s' in file %s due to: %s" % ( |
| options.get_parameter, options.file, str(err))) |
| sys.exit(1) |
| |
| if options.remove_parameter: |
| try: |
| comment_parameter(options.file, options.remove_parameter) |
| return |
| except Exception as err: |
| sys.stderr.write("Failed to remove parameter '%s' in file %s due to: %s" % |
| (options.remove_parameter, options.file, str(err))) |
| sys.exit(1) |
| |
| if options.add_parameter: |
| try: |
| comment_parameter(options.file, options.add_parameter) |
| add_parameter(options.file, options.add_parameter, options.value) |
| return |
| except Exception as err: |
| sys.stderr.write("Failed to add parameter '%s' in file %s due to: %s" % |
| (options.add_parameter, options.file, str(err))) |
| sys.exit(1) |
| |
| |
| if __name__ == "__main__": |
| main() |
