types

type Action uint32

type DefaultHttpContext struct{}

type DefaultRootContext struct{}

type DefaultTcpContext struct{}

type HttpContext interface {
	// OnHttpRequestHeaders is called when request headers arrives.
	// Return types.ActionPause if you want to stop sending headers to upstream.
	OnHttpRequestHeaders(numHeaders int, endOfStream bool) Action

	// OnHttpRequestBody is called when a request body *frame* arrives.
	// Note that this is possibly called multiple times until we see end_of_stream = true.
	// Return types.ActionPause if you want to buffer the body and stop sending body to upstream.
	// Even after returning types.ActionPause, this will be called when a unseen frame arrives.
	OnHttpRequestBody(bodySize int, endOfStream bool) Action

	// OnHttpRequestTrailers is called when request trailers arrives.
	// Return types.ActionPause if you want to stop sending trailers to upstream.
	OnHttpRequestTrailers(numTrailers int) Action

	// OnHttpResponseHeaders is called when response headers arrives.
	// Return types.ActionPause if you want to stop sending headers to downstream.
	OnHttpResponseHeaders(numHeaders int, endOfStream bool) Action

	// OnHttpResponseBody is called when a response body *frame* arrives.
	// Note that this is possibly called multiple times until we see end_of_stream = true.
	// Return types.ActionPause if you want to buffer the body and stop sending body to downtream.
	// Even after returning types.ActionPause, this will be called when a unseen frame arrives.
	OnHttpResponseBody(bodySize int, endOfStream bool) Action

	// OnHttpResponseTrailers is called when response trailers arrives.
	// Return types.ActionPause if you want to stop sending trailers to downstream.
	OnHttpResponseTrailers(numTrailers int) Action

	// OnHttpStreamDone is called before the host deletes this context.
	// You can retreive the HTTP request/response information (such headers, etc.) during this calls.
	// This can be used for implementing logging feature.
	OnHttpStreamDone()
}

type OnPluginStartStatus bool

type OnVMStartStatus bool

type PeerType uint32

type RootContext interface {
	// OnVMStart is called after the VM is created and main function is called.
	// During this call, GetVmConfiguration hostcall is available and can be used to
	// retrieve the configuration set at vm_config.configuration.
	//
	// Note that **only one root cnotext is called on this function**.
	// That is because there's Wasm VM: RootContext = 1: N correspondence, and
	// the firstly created root context of these root contexts will be treated
	// as a *VM context* on which OnVMStart is invoked by host.
	// In other words, vm_config.configuration is only available for only one root context
	// which is created first.
	OnVMStart(vmConfigurationSize int) OnVMStartStatus

	// OnPluginStart is called on all root contexts (after OnVmStart if this is the VM context).
	// During this call, hostcalls.getPluginConfiguration is available and can be used to
	// retrieve the configuration set at config.configuration in envoy.yaml
	OnPluginStart(pluginConfigurationSize int) OnPluginStartStatus

	// onPluginDone is called right before root contexts are deleted by hosts.
	// Return false to indicate it's in a pending state to do some more work left.
	// In that case, must call PluginDone() host call after the work is done to indicate that
	// hosts can kill this contexts.
	OnPluginDone() bool

	// OnQueueReady is called when the queue is ready after calling RegisterQueue hostcall.
	// Note that the queue is dequeued by another VM running in another thread, so possibly
	// the queue is empty during OnQueueReady even if it is not dequeued by this VM.
	OnQueueReady(queueID uint32)

	// OnTick is called when SetTickPeriodMilliSeconds hostcall is called by this root context.
	// This can be used for doing some asynchronous tasks in parallel to stream processing.
	OnTick()

	// The following functions are used for creating contexts on streams,
	// and developers *must* implement either of them corresponding to
	// extension points. For example, if you configure this root context is running
	// at Http filters, then NewHttpContext must be implemented. Same goes for
	// Tcp filters.
	//
	// NewTcpContext is used for creating TcpContext for each Tcp streams.
	NewTcpContext(contextID uint32) TcpContext
	// NewHttpContext is used for creating HttpContext for each Http streams.
	NewHttpContext(contextID uint32) HttpContext
}

type TcpContext interface {
	// OnNewConnection is called when the Tcp connection is established between Down and Upstreams.
	OnNewConnection() Action

	// OnDownstreamData is called when a data frame arrives from the downstream connection.
	OnDownstreamData(dataSize int, endOfStream bool) Action

	// OnDownstreamClose is called when the downstream connection is closed.
	OnDownstreamClose(peerType PeerType)

	/// OnUpstreamData is called when a data frame arrives from the upstream connection.
	OnUpstreamData(dataSize int, endOfStream bool) Action

	// OnUpstreamClose is called when the upstream connection is closed.
	OnUpstreamClose(peerType PeerType)

	// OnStreamDone is called before the host deletes this context.
	// You can retreive the stream information (such as remote addesses, etc.) during this calls
	// This can be used for implementing logging feature.
	OnStreamDone()
}