Struct postgres::config::Config

pub struct Config { /* private fields */ }

Connection configuration.

Configuration can be parsed from libpq-style connection strings. These strings come in two formats:

Key-Value

This format consists of space-separated key-value pairs. Values which are either the empty string or contain whitespace should be wrapped in '. ' and \ characters should be backslash-escaped.

Keys

• user - The username to authenticate with. Required.
• password - The password to authenticate with.
• dbname - The name of the database to connect to. Defaults to the username.
• options - Command line options used to configure the server.
• application_name - Sets the application_name parameter on the server.
• sslmode - Controls usage of TLS. If set to disable, TLS will not be used. If set to prefer, TLS will be used if available, but not used otherwise. If set to require, TLS will be forced to be used. Defaults to prefer.
• host - The host to connect to. On Unix platforms, if the host starts with a / character it is treated as the path to the directory containing Unix domain sockets. Otherwise, it is treated as a hostname. Multiple hosts can be specified, separated by commas. Each host will be tried in turn when connecting. Required if connecting with the connect method.
• port - The port to connect to. Multiple ports can be specified, separated by commas. The number of ports must be either 1, in which case it will be used for all hosts, or the same as the number of hosts. Defaults to 5432 if omitted or the empty string.
• connect_timeout - The time limit in seconds applied to each socket-level connection attempt. Note that hostnames can resolve to multiple IP addresses, and this limit is applied to each address. Defaults to no timeout.
• tcp_user_timeout - The time limit that transmitted data may remain unacknowledged before a connection is forcibly closed. This is ignored for Unix domain socket connections. It is only supported on systems where TCP_USER_TIMEOUT is available and will default to the system default if omitted or set to 0; on other systems, it has no effect.
• keepalives - Controls the use of TCP keepalive. A value of 0 disables keepalive and nonzero integers enable it. This option is ignored when connecting with Unix sockets. Defaults to on.
• keepalives_idle - The number of seconds of inactivity after which a keepalive message is sent to the server. This option is ignored when connecting with Unix sockets. Defaults to 2 hours.
• keepalives_interval - The time interval between TCP keepalive probes. This option is ignored when connecting with Unix sockets.
• keepalives_retries - The maximum number of TCP keepalive probes that will be sent before dropping a connection. This option is ignored when connecting with Unix sockets.
• target_session_attrs - Specifies requirements of the session. If set to read-write, the client will check that the transaction_read_write session parameter is set to on. This can be used to connect to the primary server in a database cluster as opposed to the secondary read-only mirrors. Defaults to all.

Examples

host=localhost user=postgres connect_timeout=10 keepalives=0

host=/var/run/postgresql,localhost port=1234 user=postgres password='password with spaces'

host=host1,host2,host3 port=1234,,5678 user=postgres target_session_attrs=read-write

Url

This format resembles a URL with a scheme of either postgres:// or postgresql://. All components are optional, and the format accept query parameters for all of the key-value pairs described in the section above. Multiple host/port pairs can be comma-separated. Unix socket paths in the host section of the URL should be percent-encoded, as the path component of the URL specifies the database name.

Examples

postgresql://user@localhost

postgresql://user:password@%2Fvar%2Frun%2Fpostgresql/mydb?connect_timeout=10

postgresql://user@host1:1234,host2,host3:5678?target_session_attrs=read-write

postgresql:///mydb?user=user&host=/var/run/postgresql

Implementations

impl Config

pub fn new() -> Config

Creates a new configuration.

pub fn user(&mut self, user: &str) -> &mut Config

Sets the user to authenticate with.

Required.

pub fn get_user(&self) -> Option<&str>

Gets the user to authenticate with, if one has been configured with the user method.

pub fn password<T>(&mut self, password: T) -> &mut Configwhere T: AsRef<[u8]>,

Sets the password to authenticate with.

pub fn get_password(&self) -> Option<&[u8]>

Gets the password to authenticate with, if one has been configured with the password method.

pub fn dbname(&mut self, dbname: &str) -> &mut Config

Sets the name of the database to connect to.

Defaults to the user.

pub fn get_dbname(&self) -> Option<&str>

Gets the name of the database to connect to, if one has been configured with the dbname method.

pub fn options(&mut self, options: &str) -> &mut Config

Sets command line options used to configure the server.

pub fn get_options(&self) -> Option<&str>

Gets the command line options used to configure the server, if the options have been set with the options method.

pub fn application_name(&mut self, application_name: &str) -> &mut Config

Sets the value of the application_name runtime parameter.

pub fn get_application_name(&self) -> Option<&str>

Gets the value of the application_name runtime parameter, if it has been set with the application_name method.

pub fn ssl_mode(&mut self, ssl_mode: SslMode) -> &mut Config

Sets the SSL configuration.

Defaults to prefer.

pub fn get_ssl_mode(&self) -> SslMode

Gets the SSL configuration.

pub fn host(&mut self, host: &str) -> &mut Config

Adds a host to the configuration.

Multiple hosts can be specified by calling this method multiple times, and each will be tried in order. On Unix systems, a host starting with a / is interpreted as a path to a directory containing Unix domain sockets.

pub fn get_hosts(&self) -> &[Host]

Gets the hosts that have been added to the configuration with host.

pub fn host_path<T>(&mut self, host: T) -> &mut Configwhere T: AsRef<Path>,

Adds a Unix socket host to the configuration.

Unlike host, this method allows non-UTF8 paths.

pub fn port(&mut self, port: u16) -> &mut Config

Adds a port to the configuration.

Multiple ports can be specified by calling this method multiple times. There must either be no ports, in which case the default of 5432 is used, a single port, in which it is used for all hosts, or the same number of ports as hosts.

pub fn get_ports(&self) -> &[u16]

Gets the ports that have been added to the configuration with port.

pub fn connect_timeout(&mut self, connect_timeout: Duration) -> &mut Config

Sets the timeout applied to socket-level connection attempts.

Note that hostnames can resolve to multiple IP addresses, and this timeout will apply to each address of each host separately. Defaults to no limit.

pub fn get_connect_timeout(&self) -> Option<&Duration>

Gets the connection timeout, if one has been set with the connect_timeout method.

pub fn tcp_user_timeout(&mut self, tcp_user_timeout: Duration) -> &mut Config

Sets the TCP user timeout.

This is ignored for Unix domain socket connections. It is only supported on systems where TCP_USER_TIMEOUT is available and will default to the system default if omitted or set to 0; on other systems, it has no effect.

pub fn get_tcp_user_timeout(&self) -> Option<&Duration>

Gets the TCP user timeout, if one has been set with the user_timeout method.

pub fn keepalives(&mut self, keepalives: bool) -> &mut Config

Controls the use of TCP keepalive.

This is ignored for Unix domain socket connections. Defaults to true.

pub fn get_keepalives(&self) -> bool

Reports whether TCP keepalives will be used.

pub fn keepalives_idle(&mut self, keepalives_idle: Duration) -> &mut Config

Sets the amount of idle time before a keepalive packet is sent on the connection.

This is ignored for Unix domain sockets, or if the keepalives option is disabled. Defaults to 2 hours.

pub fn get_keepalives_idle(&self) -> Duration

Gets the configured amount of idle time before a keepalive packet will be sent on the connection.

pub fn keepalives_interval( &mut self, keepalives_interval: Duration ) -> &mut Config

Sets the time interval between TCP keepalive probes. On Windows, this sets the value of the tcp_keepalive struct’s keepaliveinterval field.

This is ignored for Unix domain sockets, or if the keepalives option is disabled.

pub fn get_keepalives_interval(&self) -> Option<Duration>

Gets the time interval between TCP keepalive probes.

pub fn keepalives_retries(&mut self, keepalives_retries: u32) -> &mut Config

Sets the maximum number of TCP keepalive probes that will be sent before dropping a connection.

This is ignored for Unix domain sockets, or if the keepalives option is disabled.

pub fn get_keepalives_retries(&self) -> Option<u32>

Gets the maximum number of TCP keepalive probes that will be sent before dropping a connection.

pub fn target_session_attrs( &mut self, target_session_attrs: TargetSessionAttrs ) -> &mut Config

Sets the requirements of the session.

This can be used to connect to the primary server in a clustered database rather than one of the read-only secondary servers. Defaults to Any.

pub fn get_target_session_attrs(&self) -> TargetSessionAttrs

Gets the requirements of the session.

pub fn channel_binding( &mut self, channel_binding: ChannelBinding ) -> &mut Config

Sets the channel binding behavior.

Defaults to prefer.

pub fn get_channel_binding(&self) -> ChannelBinding

Gets the channel binding behavior.

pub fn notice_callback<F>(&mut self, f: F) -> &mut Configwhere F: Fn(DbError) + Send + Sync + 'static,

Sets the notice callback.

This callback will be invoked with the contents of every AsyncMessage::Notice that is received by the connection. Notices use the same structure as errors, but they are not “errors” per-se.

Notices are distinct from notifications, which are instead accessible via the Notifications API.

pub fn connect<T>(&self, tls: T) -> Result<Client, Error>where T: MakeTlsConnect<Socket> + 'static + Send, T::TlsConnect: Send, T::Stream: Send, <T::TlsConnect as TlsConnect<Socket>>::Future: Send,

Opens a connection to a PostgreSQL database.

Trait Implementations

impl Clone for Config

fn clone(&self) -> Config

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Config

fn fmt(&self, fmt: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Config

fn default() -> Config

Returns the “default value” for a type.

impl From<Config> for Config

fn from(config: Config) -> Config

Converts to this type from the input type.

impl FromStr for Config

type Err = Error

The associated error which can be returned from parsing.

fn from_str(s: &str) -> Result<Config, Error>

Parses a string s to return a value of this type.