PostgresConnection

Implements: IReferenceable, IConfigurable, IOpenable

Description

The PostgresConnection class allows you to create connections to PostgreSQL databases using the official driver.

Important points

• By defining a connection and sharing it through multiple persistence components you can reduce the number of used database connections.

Configuration parameters

• connection(s):

  • discovery_key: (optional) key to retrieve the connection from IDiscovery
  • host: host name or IP address
  • port: port number (default: 27017)
  • uri: resource URI or connection string with all parameters in it

• credential(s):

  • store_key: (optional) key to retrieve the credentials from ICredentialStore
  • username: username
  • password: user’s password

• options:

  • connect_timeout: (optional) number of milliseconds to wait before timing out when connecting a new client (default: 0)
  • idle_timeout: (optional) number of milliseconds a client must sit idle in the pool and not be checked out (default: 10000)
  • max_pool_size: (optional) maximum number of clients the pool can contain (default: 10)

References

• *:logger:*:*:1.0 - (optional) ILogger components to pass log messages
• *:discovery:*:*:1.0 - (optional) IDiscovery services
• *:credential-store:*:*:1.0 (optional) credential stores used to resolve credentials

Constructors

NewPostgresConnection

NewPostgresConnection creates a new instance of the connection component.

NewPostgresConnection() *PostgresConnection

Fields

Methods

Close

Closes a component and frees the used resources.

(c *PostgresConnection) Close(ctx context.Context, correlationId string) (err error)

• ctx: context.Context - operation context.
• correlationId: string - (optional) transaction id used to trace execution through the call chain.
• returns: (err error) - error or nil if no errors occurred.

Configure

Configures the component by passing its configuration parameters.

(c *PostgresConnection) Configure(ctx context.Context, config *cconf.ConfigParams)

• config: *cconf.ConfigParams - configuration parameters to be set.

GetConnection

Gets a connection to a Postgres database.

(c *PostgresConnection) GetConnection() *pgxpool.Pool

• returns: *pgxpool.Pool - connection to a Postgres database.

GetDatabaseName

Gets the database name.

(c *PostgresConnection) GetDatabaseName() string

• returns: string - database name

Open

Opens the component.

(c *PostgresConnection) Open(ctx context.Context, correlationId string) (err error)

• ctx: context.Context - operation context.
• correlationId: string - (optional) transaction id used to trace execution through the call chain.
• returns: (err error) - error or nil if no errors occurred.

SetReferences

Sets references to dependent components.

(c *PostgresConnection) SetReferences(ctx context.Context, references IReferences)

• ctx context.Context - operation context.
• references: IReferences - references to locate the component’s dependencies.