patroni.config_generator module

patroni --generate-config machinery.

class patroni.config_generator.AbstractConfigGenerator(output_file: str | None)

Bases: ABC

Object representing the generated Patroni config.

Variables:

• output_file – full path to the output file to be used.

• pg_major – integer representation of the major PostgreSQL version.

• config – dictionary used for the generated configuration storage.

__init__(output_file: str | None) → None

Set up the output file (if passed), helper vars and the minimal config structure.

Parameters:

output_file – full path to the output file to be used.

_abc_impl = <_abc._abc_data object>

static _format_block(block: Any, line_prefix: str = '') → str

Format a single YAML block.

Note

Optionally the formatted block could be indented with the line_prefix

Parameters:

• block – the object that should be formatted to YAML.

• line_prefix – is used for indentation.

Returns:

a formatted and indented block.

_format_config() → Iterator[str]

Format current config and enrich it with some comments.

Yields:

formatted lines or blocks that represent a text output of the YAML document.

_format_config_section(section_name: str) → Iterator[str]

Format and yield as single section of the current config.

Note

If the section is a dict object we put an empty line before it.

Parameters:

section_name – a section name in the config.

Yields:

a formatted section in case if it exists in the config.

_write_config_to_fd(fd: TextIO) → None

Format and write current config to provided file descriptor.

Parameters:

fd – where to write the config file. Could be sys.stdout or the real file.

abstractmethod generate() → None

Generate config and store in config.

classmethod get_template_config() → Dict[str, Any]

Generate a template config for further extension (e.g. in the inherited classes).

Returns:

dictionary with the values gathered from Patroni env, hopefully defined hostname and ip address (otherwise set to NO_VALUE_MSG), and some sane defaults.

write_config() → None

Write current config to the output file if provided, to stdout otherwise.

class patroni.config_generator.RunningClusterConfigGenerator(output_file: str | None = None, dsn: str | None = None)

Bases: AbstractConfigGenerator

Object representing the Patroni config generated using information gathered from the running instance.

Variables:

• dsn – DSN string for the local instance to get GUC values from (if provided).

• parsed_dsn – DSN string parsed into a dictionary (see parse_dsn()).

__init__(output_file: str | None = None, dsn: str | None = None) → None

Additionally store the passed dsn (if any) in both original and parsed version and run config generation.

Parameters:

• output_file – full path to the output file to be used.

• dsn – DSN string for the local instance to get GUC values from.

Raises:

PatroniException: if DSN parsing failed.

_abc_impl = <_abc._abc_data object>

_enrich_config_from_running_instance() → None

Extend config with the values gathered from the running instance.

Retrieve the following information from the running PostgreSQL instance:

• superuser auth parameters (see _set_su_params());

• some GUC values (see _set_pg_params());

• postgresql.connect_address, postgresql.listen;

• postgresql.pg_hba and postgresql.pg_ident (see _set_conf_files())

And redefine scope with the cluster_name GUC value if set.

Raises:

PatroniException: if the provided user doesn’t have superuser privileges.

_get_bin_dir_from_running_instance() → str

Define the directory postgres binaries reside using postmaster’s pid executable.

Returns:

path to the PostgreSQL binaries directory.

Raises:

PatroniException: if:

• pid could not be obtained from the postmaster.pid file; or

• OSError occurred during postmaster.pid file handling; or

• the obtained postmaster pid doesn’t exist.

_get_connection_cursor() → Iterator[cursor | Cursor[Any]]

Get cursor for the PG connection established based on the stored information.

Raises:

PatroniException: if psycopg.Error occurred.

property _get_hba_conn_types: Tuple[str, ...]

Return the connection types allowed.

If pg_major is defined, adds additional parameters for PostgreSQL version >=16.

Returns:

tuple of the connection methods allowed.

property _required_pg_params: List[str]

PG configuration parameters that have to be always present in the generated config.

Returns:

list of the parameter names.

_set_conf_files() → None

Extend config with pg_hba.conf and pg_ident.conf content.

Note

This function only defines postgresql.pg_hba and postgresql.pg_ident when hba_file and ident_file are set to the defaults. It may happen these files are located outside of PGDATA and Patroni doesn’t have write permissions for them.

Raises:

PatroniException: if OSError occurred during the conf files handling.

_set_pg_params(cur: cursor | Cursor[Any]) → None

Extend config with the actual PG GUCs values.

THe following GUC values are set:

• Non-internal having configuration file, postmaster command line or environment variable as a source.

• List of the always required parameters (see _required_pg_params()).

Parameters:

cur – connection cursor to use.

_set_su_params() → None

Extend config with the superuser auth information.

Information set is based on the options used for connection.

generate() → None

Generate config using the info gathered from the specified running PG instance.

Result is written to config.

class patroni.config_generator.SampleConfigGenerator(output_file: str | None)

Bases: AbstractConfigGenerator

Object representing the generated sample Patroni config.

Sane defaults are used based on the gathered PG version.

_abc_impl = <_abc._abc_data object>

_get_int_major_version() → int

Get major PostgreSQL version from the binary as an integer.

Returns:

an integer PostgreSQL major version representation gathered from the PostgreSQL binary. See postgres_major_version_to_int() and get_major_version().

generate() → None

Generate sample config using some sane defaults and update config.

property get_auth_method: str

Return the preferred authentication method for a specific PG version if provided or the default md5.

Returns:

str value for the preferred authentication method.

patroni.config_generator.generate_config(output_file: str, sample: bool, dsn: str | None) → None

Generate Patroni configuration file.

Parameters:

• output_file – Full path to the configuration file to be used. If not provided, result is sent to stdout.

• sample – Optional flag. If set, no source instance will be used - generate config with some sane defaults.

• dsn – Optional DSN string for the local instance to get GUC values from.

patroni.config_generator.get_address() → Tuple[str, str]

Try to get hostname and the ip address for it returned by gethostname().

Note

Can also return local ip.

Returns:

tuple consisting of the hostname returned by gethostname() and the first element in the sorted list of the addresses returned by getaddrinfo(). Sorting guarantees it will prefer IPv4. If an exception occurred, hostname and ip values are equal to NO_VALUE_MSG.