conn

Documentation

Overview

Package conn implements a bi-directional communication channel between an envelope and a weavelet.

Index

• func Profile(req *protos.GetProfileRequest) ([]byte, error)
• type EnvelopeConn
  • func NewEnvelopeConn(ctx context.Context, r io.ReadCloser, w io.WriteCloser, ...) (*EnvelopeConn, error)
  • func (e *EnvelopeConn) GetHealthRPC() (protos.HealthStatus, error)
  • func (e *EnvelopeConn) GetLoadRPC() (*protos.LoadReport, error)
  • func (e *EnvelopeConn) GetMetricsRPC() ([]*metrics.MetricSnapshot, error)
  • func (e *EnvelopeConn) GetProfileRPC(req *protos.GetProfileRequest) ([]byte, error)
  • func (e *EnvelopeConn) Serve(h EnvelopeHandler) error
  • func (e *EnvelopeConn) UpdateComponentsRPC(components []string) error
  • func (e *EnvelopeConn) UpdateRoutingInfoRPC(routing *protos.RoutingInfo) error
  • func (e *EnvelopeConn) WeaveletInfo() *protos.WeaveletInfo
• type EnvelopeHandler
• type WeaveletConn
  • func NewWeaveletConn(r io.ReadCloser, w io.WriteCloser, h WeaveletHandler) (*WeaveletConn, error)
  • func (d *WeaveletConn) ActivateComponentRPC(req *protos.ActivateComponentRequest) error
  • func (d *WeaveletConn) EnvelopeInfo() *protos.EnvelopeInfo
  • func (d *WeaveletConn) ExportListenerRPC(req *protos.ExportListenerRequest) (*protos.ExportListenerReply, error)
  • func (d *WeaveletConn) GetListenerAddressRPC(req *protos.GetListenerAddressRequest) (*protos.GetListenerAddressReply, error)
  • func (d *WeaveletConn) Listener() net.Listener
  • func (d *WeaveletConn) SendLogEntry(entry *protos.LogEntry) error
  • func (d *WeaveletConn) SendTraceSpans(spans *protos.TraceSpans) error
  • func (d *WeaveletConn) Serve() error
• type WeaveletHandler

Functions

func Profile

func Profile(req *protos.GetProfileRequest) ([]byte, error)

Profile collects profiles for the weavelet.

Types

type EnvelopeConn

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

EnvelopeConn is the envelope side of the connection between a weavelet and an envelope. For more information, refer to runtime/protos/runtime.proto and https://serviceweaver.dev/blog/deployers.html.

func NewEnvelopeConn

func NewEnvelopeConn(ctx context.Context, r io.ReadCloser, w io.WriteCloser, info *protos.EnvelopeInfo) (*EnvelopeConn, error)

NewEnvelopeConn returns a connection to an already started weavelet. The connection sends messages to and receives messages from the weavelet using r and w. The provided EnvelopeInfo is sent to the weavelet as part of the handshake.

You can issue RPCs *to* the weavelet using the returned EnvelopeConn. To start receiving messages *from* the weavelet, call [Serve].

The connection stops on error or when the provided context is canceled.

func (*EnvelopeConn) GetHealthRPC

func (e *EnvelopeConn) GetHealthRPC() (protos.HealthStatus, error)

GetHealthRPC gets a weavelet's health.

func (*EnvelopeConn) GetLoadRPC

func (e *EnvelopeConn) GetLoadRPC() (*protos.LoadReport, error)

GetLoadRPC gets a load report from the weavelet.

func (*EnvelopeConn) GetMetricsRPC

func (e *EnvelopeConn) GetMetricsRPC() ([]*metrics.MetricSnapshot, error)

GetMetricsRPC gets a weavelet's metrics. There can only be one outstanding GetMetricsRPC at a time.

func (*EnvelopeConn) GetProfileRPC

func (e *EnvelopeConn) GetProfileRPC(req *protos.GetProfileRequest) ([]byte, error)

GetProfileRPC gets a profile from the weavelet. There can only be one outstanding GetProfileRPC at a time.

func (*EnvelopeConn) Serve

func (e *EnvelopeConn) Serve(h EnvelopeHandler) error

Serve accepts incoming messages from the weavelet. RPC requests are handled serially in the order they are received. Serve blocks until the connection terminates, returning the error that caused it to terminate. You can cancel the connection by cancelling the context passed to NewEnvelopeConn. This method never returns a non-nil error.

func (*EnvelopeConn) UpdateComponentsRPC

func (e *EnvelopeConn) UpdateComponentsRPC(components []string) error

UpdateComponentsRPC updates the weavelet with the latest set of components it should be running.

func (*EnvelopeConn) UpdateRoutingInfoRPC

func (e *EnvelopeConn) UpdateRoutingInfoRPC(routing *protos.RoutingInfo) error

UpdateRoutingInfoRPC updates the weavelet with a component's most recent routing info.

func (*EnvelopeConn) WeaveletInfo

func (e *EnvelopeConn) WeaveletInfo() *protos.WeaveletInfo

WeaveletInfo returns information about the weavelet.

type EnvelopeHandler

type EnvelopeHandler interface {
	ActivateComponent(context.Context, *protos.ActivateComponentRequest) (*protos.ActivateComponentReply, error)
	GetListenerAddress(context.Context, *protos.GetListenerAddressRequest) (*protos.GetListenerAddressReply, error)
	ExportListener(context.Context, *protos.ExportListenerRequest) (*protos.ExportListenerReply, error)
	HandleLogEntry(context.Context, *protos.LogEntry) error
	HandleTraceSpans(context.Context, []trace.ReadOnlySpan) error
}

See envelope.EnvelopeHandler

type WeaveletConn

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

WeaveletConn is the weavelet side of the connection between a weavelet and an envelope. For more information, refer to runtime/protos/runtime.proto and https://serviceweaver.dev/blog/deployers.html.

func NewWeaveletConn

func NewWeaveletConn(r io.ReadCloser, w io.WriteCloser, h WeaveletHandler) (*WeaveletConn, error)

NewWeaveletConn returns a connection to an envelope. The connection sends messages to and receives messages from the envelope using r and w. Note that all RPCs will block until [Serve] is called.

TODO(mwhittaker): Pass in a context.Context?

func (*WeaveletConn) ActivateComponentRPC

func (d *WeaveletConn) ActivateComponentRPC(req *protos.ActivateComponentRequest) error

ActivateComponentRPC ensures that the provided component is running somewhere. A call to ActivateComponentRPC also implicitly signals that a weavelet is interested in receiving routing info for the component.

func (*WeaveletConn) EnvelopeInfo

func (d *WeaveletConn) EnvelopeInfo() *protos.EnvelopeInfo

EnvelopeInfo returns the EnvelopeInfo received from the envelope.

func (*WeaveletConn) ExportListenerRPC

func (d *WeaveletConn) ExportListenerRPC(req *protos.ExportListenerRequest) (*protos.ExportListenerReply, error)

ExportListenerRPC exports the provided listener.

func (*WeaveletConn) GetListenerAddressRPC

func (d *WeaveletConn) GetListenerAddressRPC(req *protos.GetListenerAddressRequest) (*protos.GetListenerAddressReply, error)

GetListenerAddressRPC returns the address the weavelet should listen on for a particular listener.

func (*WeaveletConn) Listener

func (d *WeaveletConn) Listener() net.Listener

Listener returns the internal network listener for the weavelet.

func (*WeaveletConn) SendLogEntry

func (d *WeaveletConn) SendLogEntry(entry *protos.LogEntry) error

SendLogEntry sends a log entry to the envelope, without waiting for a reply.

func (*WeaveletConn) SendTraceSpans

func (d *WeaveletConn) SendTraceSpans(spans *protos.TraceSpans) error

SendTraceSpans sends a set of trace spans to the envelope, without waiting for a reply.

func (*WeaveletConn) Serve

func (d *WeaveletConn) Serve() error

Serve accepts RPC requests from the envelope. Requests are handled serially in the order they are received.

type WeaveletHandler

type WeaveletHandler interface {

	// GetLoad returns a load report.
	GetLoad(*protos.GetLoadRequest) (*protos.GetLoadReply, error)

	// UpdateComponents updates the set of components the weavelet should be
	// running. Currently, the set of components only increases over time.
	UpdateComponents(*protos.UpdateComponentsRequest) (*protos.UpdateComponentsReply, error)

	// UpdateRoutingInfo updates a component's routing information.
	UpdateRoutingInfo(*protos.UpdateRoutingInfoRequest) (*protos.UpdateRoutingInfoReply, error)
}

WeaveletHandler handles messages from the envelope. A handler should not block and should not perform RPCs over the pipe. Values passed to the handlers are only valid for the duration of the handler's execution.