pgadapter

type Config struct {
	// ConnectToEmulator specifies whether PGAdapter should connect to the Cloud Spanner emulator,
	// or whether it should connect to real Cloud Spanner.
	// Setting this option to true will force the use of Docker as the ExecutionEnvironment, and all
	// other configuration options will be ignored.
	ConnectToEmulator bool

	// ExecutionEnvironment determines the execution environment that is used to start
	// PGAdapter.
	//
	// Java starts PGAdapter on localhost as a Java application. This requires Java to be
	// installed on the local system. See for example https://adoptium.net/installation/
	// for information on how to install an open-source Java distribution on your system.
	//
	// Java is the recommended setting for production environments, as it means that your
	// application and PGAdapter are both running on the same host, and the network traffic
	// does not need to pass over the host-to-Docker network bridge. Note that it is perfectly
	// OK to run both your application and PGAdapter in the same Docker container.
	//
	// The Java process is automatically shut down when your application shuts down.
	//
	// Docker starts PGAdapter in a test container instance. This is recommended for testing
	// and development, but not for production, as it means that the network communication
	// between your application and PGAdapter crosses the host-to-Docker network bridge.
	// This network interface is slow compared to network communication directly on localhost.
	//
	// This variable must be set.
	ExecutionEnvironment ExecutionEnvironment

	// Project specifies the Google Cloud project that PGAdapter should connect to.
	// This value is optional. If it is not set, clients that connect to the PGAdapter
	// instance must use a fully qualified database name when connecting.
	Project string
	// Instance specifies the Google Cloud Spanner instance that PGAdapter should
	// connect to. This value is optional. If it is not set, clients that connect
	// to the PGAdapter instance must use a fully qualified database name when connecting.
	Instance string
	// Database specifies the Google Cloud Spanner database that PGAdapter should
	// connect to. This value is optional. If it is set, any database name in the
	// connection URL of a PostgreSQL client will be ignored, and PGAdapter will always
	// connect to this specific database.
	// If Database is not set, then PGAdapter will use the database name from the
	// PostgreSQL connection URL.
	Database string
	// CredentialsFile is the user account or service account key file that PGAdapter
	// should use to connect to Cloud Spanner.
	// This value is optional. If it is not set, PGAdapter will use the default
	// credentials in the runtime environment.
	CredentialsFile string
	// Set RequireAuthentication to instruct PGAdapter to require PostgreSQL clients
	// to authenticate when connecting. When enabled, clients must supply the Google
	// Cloud credentials that should be used in the password field of the startup
	// message. See https://github.com/GoogleCloudPlatform/pgadapter/docs/authentication.md
	// for more information.
	RequireAuthentication bool

	// MinSessions is the minimum number of Cloud Spanner sessions in the internal
	// session pool of PGAdapter. These sessions are created directly when PGAdapter
	// is started.
	MinSessions int
	// MaxSessions is the maximum number of Cloud Spanner sessions in the internal
	// session pool of PGAdapter. The maximum number of sessions should be set to
	// the maximum number of concurrent transactions that your application might
	// execute.
	MaxSessions int
	// NumChannels is the number of gRPC channels that PGAdapter creates and uses
	// to communicate with Cloud Spanner.
	NumChannels int
	// DatabaseRole specifies the fine-grained access control role that PGAdapter
	// should use when connecting to Cloud Spanner.
	DatabaseRole string

	// Port is the host TCP port where PGAdapter should listen for incoming connections.
	// The port must not be in use by any other process.
	// Use port 0 to dynamically assign an available port to PGAdapter.
	//
	// The port must be 0 (dynamic assignment) for execution environment Docker.
	Port int

	// Version is the PGAdapter version that should be started.
	// Leave this string empty to use the most recent version.
	Version string
}

type Docker struct {
	// Set AlwaysPullImage to true to ensure that the latest image of PGAdapter is
	// pulled before it is started.
	AlwaysPullImage bool
	// Set KeepContainer to keep the container after it has stopped. The Docker
	// container is started with the '--rm' option by default, unless this option
	// is set.
	KeepContainer bool
}

type DownloadSettings struct {
	// DownloadLocation specifies the location where the PGAdapter jar should be
	// stored. It will use the directory that is returned by os.UserCacheDirectory()
	// if no location is specified.
	DownloadLocation string

	// DisableAutomaticDownload can be used to disable the automatic download of the
	// PGAdapter jar. Set this if you do not want this wrapper to automatically download
	// the PGAdapter jar, for example if the machine does not have permission to write
	// to the local file system.
	DisableAutomaticDownload bool
}

type ExecutionEnvironment interface {
	// Command returns the command and arguments that is the equivalent of
	// this ExecutionEnvironment. Use the output of this command to get the
	// equivalent command for starting PGAdapter manually.
	//
	// Example return value for Java:
	//
	// java -jar pgadapter.jar -p my-project -i my-instance -d my-database -c /path/to/credentials.json
	//
	// Example return value for Docker:
	//
	// docker run
	// 	 -d \
	//   -p 5432 \
	//   gcr.io/cloud-spanner-pg-adapter/pgadapter \
	//   -p my-project -i my-instance -d my-database \
	//   -c /credentials.json -x
	Command(config Config) (string, error)
	// contains filtered or unexported methods
}

type Java struct {
	DownloadSettings DownloadSettings
}

type PGAdapter struct {
	// contains filtered or unexported fields
}