mirror of
https://github.com/postmannen/ctrl.git
synced 2024-12-14 12:37:31 +00:00
751 lines
26 KiB
Go
751 lines
26 KiB
Go
package steward
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import (
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"bytes"
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"compress/gzip"
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"context"
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"crypto/ed25519"
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"encoding/gob"
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"fmt"
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"io"
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"log"
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"os"
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"sync"
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"time"
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"github.com/fxamacker/cbor/v2"
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"github.com/klauspost/compress/zstd"
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"github.com/nats-io/nats.go"
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"github.com/prometheus/client_golang/prometheus"
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)
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// processKind are either kindSubscriber or kindPublisher, and are
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// used to distinguish the kind of process to spawn and to know
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// the process kind put in the process map.
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type processKind string
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const (
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processKindSubscriber processKind = "subscriber"
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processKindPublisher processKind = "publisher"
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)
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// process holds all the logic to handle a message type and it's
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// method, subscription/publishin messages for a subject, and more.
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type process struct {
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messageID int
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// the subject used for the specific process. One process
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// can contain only one sender on a message bus, hence
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// also one subject
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subject Subject
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// Put a node here to be able know the node a process is at.
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// NB: Might not be needed later on.
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node Node
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// The processID for the current process
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processID int
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processKind processKind
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// methodsAvailable
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methodsAvailable MethodsAvailable
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// Helper or service function that can do some kind of work
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// for the process.
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// The idea is that this can hold for example the map of the
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// the hello nodes to limit shared resources in the system as
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// a whole for sharing a map from the *server level.
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procFunc procFunc
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// The channel to send a messages to the procFunc go routine.
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// This is typically used within the methodHandler for so we
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// can pass messages between the procFunc and the handler.
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procFuncCh chan Message
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// copy of the configuration from server
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configuration *Configuration
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// The new messages channel copied from *Server
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toRingbufferCh chan<- []subjectAndMessage
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// The structure who holds all processes information
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processes *processes
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// nats connection
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natsConn *nats.Conn
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// natsSubscription returned when calling natsConn.Subscribe
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natsSubscription *nats.Subscription
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// context
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ctx context.Context
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// context cancelFunc
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ctxCancel context.CancelFunc
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// Process name
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processName processName
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// startup holds the startup functions for starting up publisher
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// or subscriber processes
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startup *startup
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// Signatures
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signatures *signatures
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}
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// prepareNewProcess will set the the provided values and the default
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// values for a process.
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func newProcess(ctx context.Context, metrics *metrics, natsConn *nats.Conn, processes *processes, toRingbufferCh chan<- []subjectAndMessage, configuration *Configuration, subject Subject, processKind processKind, procFunc func() error, signatures *signatures) process {
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// create the initial configuration for a sessions communicating with 1 host process.
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processes.lastProcessID++
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ctx, cancel := context.WithCancel(ctx)
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var method Method
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proc := process{
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messageID: 0,
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subject: subject,
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node: Node(configuration.NodeName),
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processID: processes.lastProcessID,
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processKind: processKind,
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methodsAvailable: method.GetMethodsAvailable(),
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toRingbufferCh: toRingbufferCh,
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configuration: configuration,
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processes: processes,
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natsConn: natsConn,
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ctx: ctx,
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ctxCancel: cancel,
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startup: newStartup(metrics, signatures),
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signatures: signatures,
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}
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return proc
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}
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// procFunc is a function that will be started when a worker process
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// is started. If a procFunc is registered when creating a new process
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// the procFunc will be started as a go routine when the process is started,
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// and stopped when the process is stopped.
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//
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// A procFunc can be started both for publishing and subscriber processes.
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//
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// When used with a subscriber process the usecase is most likely to handle
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// some kind of state needed for a request type. The handlers themselves
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// can not hold state since they are only called once per message received,
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// and exits when the message is handled leaving no state behind. With a procfunc
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// we can have a process function running at all times tied to the process, and
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// this function can be able to hold the state needed in a certain scenario.
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//
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// With a subscriber handler you generally take the message in the handler and
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// pass it on to the procFunc by putting it on the procFuncCh<-, and the
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// message can then be read from the procFuncCh inside the procFunc, and we
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// can do some further work on it, for example update registry for metrics that
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// is needed for that specific request type.
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//
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// With a publisher process you can attach a static function that will do some
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// work to a request type, and publish the result.
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//
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// procFunc's can also be used to wrap in other types which we want to
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// work with. An example can be handling of metrics which the message
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// have no notion of, but a procFunc can have that wrapped in from when it was constructed.
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type procFunc func(ctx context.Context, procFuncCh chan Message) error
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// The purpose of this function is to check if we should start a
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// publisher or subscriber process, where a process is a go routine
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// that will handle either sending or receiving messages on one
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// subject.
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//
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// It will give the process the next available ID, and also add the
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// process to the processes map in the server structure.
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func (p process) spawnWorker(procs *processes, natsConn *nats.Conn) {
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// We use the full name of the subject to identify a unique
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// process. We can do that since a process can only handle
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// one message queue.
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var pn processName
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if p.processKind == processKindPublisher {
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pn = processNameGet(p.subject.name(), processKindPublisher)
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}
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if p.processKind == processKindSubscriber {
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pn = processNameGet(p.subject.name(), processKindSubscriber)
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}
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processName := processNameGet(p.subject.name(), p.processKind)
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// Add prometheus metrics for the process.
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p.processes.metrics.promProcessesAllRunning.With(prometheus.Labels{"processName": string(processName)})
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// Start a publisher worker, which will start a go routine (process)
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// That will take care of all the messages for the subject it owns.
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if p.processKind == processKindPublisher {
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// If there is a procFunc for the process, start it.
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if p.procFunc != nil {
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// Initialize the channel for communication between the proc and
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// the procFunc.
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p.procFuncCh = make(chan Message)
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// Start the procFunc in it's own anonymous func so we are able
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// to get the return error.
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go func() {
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err := p.procFunc(p.ctx, p.procFuncCh)
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if err != nil {
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er := fmt.Errorf("error: spawnWorker: start procFunc failed: %v", err)
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p.processes.errorKernel.errSend(p, Message{}, er)
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}
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}()
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}
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go p.publishMessages(natsConn)
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}
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// Start a subscriber worker, which will start a go routine (process)
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// That will take care of all the messages for the subject it owns.
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if p.processKind == processKindSubscriber {
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// If there is a procFunc for the process, start it.
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if p.procFunc != nil {
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// Initialize the channel for communication between the proc and
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// the procFunc.
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p.procFuncCh = make(chan Message)
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// Start the procFunc in it's own anonymous func so we are able
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// to get the return error.
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go func() {
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err := p.procFunc(p.ctx, p.procFuncCh)
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if err != nil {
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er := fmt.Errorf("error: spawnWorker: start procFunc failed: %v", err)
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p.processes.errorKernel.errSend(p, Message{}, er)
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}
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}()
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}
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p.natsSubscription = p.subscribeMessages()
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}
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p.processName = pn
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// Add information about the new process to the started processes map.
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procs.active.mu.Lock()
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procs.active.procNames[pn] = p
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procs.active.mu.Unlock()
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}
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// messageDeliverNats will create the Nats message with headers and payload.
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// It will also take care of the delivering the message that is converted to
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// gob or cbor format as a nats.Message. It will also take care of checking
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// timeouts and retries specified for the message.
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func (p process) messageDeliverNats(natsMsgPayload []byte, natsMsgHeader nats.Header, natsConn *nats.Conn, message Message) {
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retryAttempts := 0
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const publishTimer time.Duration = 5
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const subscribeSyncTimer time.Duration = 5
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// The for loop will run until the message is delivered successfully,
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// or that retries are reached.
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for {
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msg := &nats.Msg{
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Subject: string(p.subject.name()),
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// Subject: fmt.Sprintf("%s.%s.%s", proc.node, "command", "CLICommandRequest"),
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// Structure of the reply message are:
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// <nodename>.<message type>.<method>.reply
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Reply: fmt.Sprintf("%s.reply", p.subject.name()),
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Data: natsMsgPayload,
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Header: natsMsgHeader,
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}
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// If it is a NACK message we just deliver the message and return
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// here so we don't create a ACK message and then stop waiting for it.
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if p.subject.Event == EventNACK {
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err := natsConn.PublishMsg(msg)
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if err != nil {
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er := fmt.Errorf("error: nats publish of hello failed: %v", err)
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log.Printf("%v\n", er)
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return
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}
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p.processes.metrics.promNatsDeliveredTotal.Inc()
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return
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}
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// The SubscribeSync used in the subscriber, will get messages that
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// are sent after it started subscribing.
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//
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// Create a subscriber for the ACK reply message.
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subReply, err := natsConn.SubscribeSync(msg.Reply)
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if err != nil {
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er := fmt.Errorf("error: nats SubscribeSync failed: failed to create reply message for subject: %v, error: %v", msg.Reply, err)
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// sendErrorLogMessage(p.toRingbufferCh, node(p.node), er)
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log.Printf("%v, waiting %ds before retrying\n", er, subscribeSyncTimer)
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time.Sleep(time.Second * subscribeSyncTimer)
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subReply.Unsubscribe()
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continue
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}
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// Publish message
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err = natsConn.PublishMsg(msg)
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if err != nil {
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er := fmt.Errorf("error: nats publish failed: %v", err)
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// sendErrorLogMessage(p.toRingbufferCh, node(p.node), er)
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log.Printf("%v, waiting %ds before retrying\n", er, publishTimer)
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time.Sleep(time.Second * publishTimer)
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continue
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}
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// If the message is an ACK type of message we must check that a
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// reply, and if it is not we don't wait here at all.
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if p.subject.Event == EventACK {
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// Wait up until ACKTimeout specified for a reply,
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// continue and resend if no reply received,
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// or exit if max retries for the message reached.
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_, err := subReply.NextMsg(time.Second * time.Duration(message.ACKTimeout))
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if err != nil {
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er := fmt.Errorf("error: ack receive failed: subject=%v: %v", p.subject.name(), err)
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// sendErrorLogMessage(p.toRingbufferCh, p.node, er)
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log.Printf(" ** %v\n", er)
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// did not receive a reply, decide what to do..
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retryAttempts++
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log.Printf("Retry attempt:%v, retries: %v, ACKTimeout: %v, message.ID: %v\n", retryAttempts, message.Retries, message.ACKTimeout, message.ID)
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switch {
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//case message.Retries == 0:
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// // 0 indicates unlimited retries
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// continue
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case retryAttempts >= message.Retries:
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// max retries reached
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er := fmt.Errorf("info: toNode: %v, fromNode: %v, subject: %v, methodArgs: %v: max retries reached, check if node is up and running and if it got a subscriber started for the given REQ type", message.ToNode, message.FromNode, msg.Subject, message.MethodArgs)
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// We do not want to send errorLogs for REQErrorLog type since
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// it will just cause an endless loop.
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if message.Method != REQErrorLog {
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p.processes.errorKernel.infoSend(p, message, er)
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}
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log.Printf("%v\n", er)
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subReply.Unsubscribe()
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p.processes.metrics.promNatsMessagesFailedACKsTotal.Inc()
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return
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default:
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// none of the above matched, so we've not reached max retries yet
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log.Printf("max retries for message not reached, retrying sending of message with ID %v\n", message.ID)
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p.processes.metrics.promNatsMessagesMissedACKsTotal.Inc()
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continue
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}
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}
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// REMOVED: log.Printf("<--- publisher: received ACK from:%v, for: %v, data: %s\n", message.ToNode, message.Method, msgReply.Data)
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}
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subReply.Unsubscribe()
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p.processes.metrics.promNatsDeliveredTotal.Inc()
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return
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}
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}
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// messageSubscriberHandler will deserialize the message when a new message is
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// received, check the MessageType field in the message to decide what
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// kind of message it is and then it will check how to handle that message type,
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// and then call the correct method handler for it.
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//
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// This handler function should be started in it's own go routine,so
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// one individual handler is started per message received so we can keep
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// the state of the message being processed, and then reply back to the
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// correct sending process's reply, meaning so we ACK back to the correct
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// publisher.
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func (p process) messageSubscriberHandler(natsConn *nats.Conn, thisNode string, msg *nats.Msg) {
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// Variable to hold a copy of the message data, so we don't mess with
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// the original data since the original is a pointer value.
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msgData := make([]byte, len(msg.Data))
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copy(msgData, msg.Data)
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// fmt.Printf(" * DEBUG: header value on subscriberHandler: %v\n", msg.Header)
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// If compression is used, decompress it to get the gob data. If
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// compression is not used it is the gob encoded data we already
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// got in msgData so we do nothing with it.
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if val, ok := msg.Header["cmp"]; ok {
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// fmt.Printf(" * DEBUG: ok = %v, map = %v, len of val = %v\n", ok, msg.Header, len(val))
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switch val[0] {
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case "z":
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zr, err := zstd.NewReader(nil)
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if err != nil {
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log.Printf("error: zstd NewReader failed: %v\n", err)
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return
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}
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msgData, err = zr.DecodeAll(msg.Data, nil)
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if err != nil {
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er := fmt.Errorf("error: zstd decoding failed: %v", err)
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log.Printf("%v\n", er)
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p.processes.errorKernel.errSend(p, Message{}, er)
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zr.Close()
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return
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}
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zr.Close()
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case "g":
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r := bytes.NewReader(msgData)
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gr, err := gzip.NewReader(r)
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if err != nil {
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log.Printf("error: gzip NewReader failed: %v\n", err)
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return
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}
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b, err := io.ReadAll(gr)
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if err != nil {
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log.Printf("error: gzip ReadAll failed: %v\n", err)
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return
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}
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gr.Close()
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msgData = b
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}
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}
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message := Message{}
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// Check if serialization is specified.
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// Will default to gob serialization if nothing or non existing value is specified is specified.
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if val, ok := msg.Header["serial"]; ok {
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// fmt.Printf(" * DEBUG: ok = %v, map = %v, len of val = %v\n", ok, msg.Header, len(val))
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switch val[0] {
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case "cbor":
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err := cbor.Unmarshal(msgData, &message)
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if err != nil {
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er := fmt.Errorf("error: cbor decoding failed: %v", err)
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log.Printf("%v\n", er)
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p.processes.errorKernel.errSend(p, message, er)
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return
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}
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default: // Deaults to gob if no match was found.
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r := bytes.NewReader(msgData)
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gobDec := gob.NewDecoder(r)
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err := gobDec.Decode(&message)
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if err != nil {
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er := fmt.Errorf("error: gob decoding failed: %v", err)
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log.Printf("%v\n", er)
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p.processes.errorKernel.errSend(p, message, er)
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return
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}
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}
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} else {
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// Default to gob if serialization flag was not specified.
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r := bytes.NewReader(msgData)
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gobDec := gob.NewDecoder(r)
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err := gobDec.Decode(&message)
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if err != nil {
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er := fmt.Errorf("error: gob decoding failed: %v", err)
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log.Printf("%v\n", er)
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p.processes.errorKernel.errSend(p, message, er)
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return
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}
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}
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// Send final reply for a relayed message back to the originating node.
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//
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// Check if the previous message was a relayed message, and if true
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// make a copy of the current message where the to field is set to
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// the value of the previous message's RelayFromNode field, so we
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// also can send the a copy of the reply back to where it originated.
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if message.PreviousMessage != nil && message.PreviousMessage.RelayOriginalViaNode != "" {
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// make a copy of the message
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msgCopy := message
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msgCopy.ToNode = msgCopy.PreviousMessage.RelayFromNode
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// We set the replyMethod of the initial message.
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// If no RelayReplyMethod was found, we default to the reply
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// method of the previous message.
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switch {
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case msgCopy.PreviousMessage.RelayReplyMethod == "":
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er := fmt.Errorf("error: subscriberHandler: no PreviousMessage.RelayReplyMethod found, defaulting to the reply method of previous message: %v ", msgCopy)
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p.processes.errorKernel.errSend(p, message, er)
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log.Printf("%v\n", er)
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msgCopy.Method = msgCopy.PreviousMessage.ReplyMethod
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case msgCopy.PreviousMessage.RelayReplyMethod != "":
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msgCopy.Method = msgCopy.PreviousMessage.RelayReplyMethod
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}
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// Reset the previousMessage relay fields so the message don't loop.
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message.PreviousMessage.RelayViaNode = ""
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message.PreviousMessage.RelayOriginalViaNode = ""
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// Create a SAM for the msg copy that will be sent back the where the
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// relayed message originated from.
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sam, err := newSubjectAndMessage(msgCopy)
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if err != nil {
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er := fmt.Errorf("error: subscriberHandler: newSubjectAndMessage : %v, message copy: %v", err, msgCopy)
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p.processes.errorKernel.errSend(p, message, er)
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log.Printf("%v\n", er)
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}
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p.toRingbufferCh <- []subjectAndMessage{sam}
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}
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// Check if it is an ACK or NACK message, and do the appropriate action accordingly.
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//
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// With ACK messages Steward will keep the state of the message delivery, and try to
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// resend the message if an ACK is not received within the timeout/retries specified
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// in the message.
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// When a process sends an ACK message, it will stop and wait for the nats-reply message
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|
// for the time specified in the replyTimeout value. If no reply message is received
|
|
// within the given timeout the publishing process will try to resend the message for
|
|
// number of times specified in the retries field of the Steward message.
|
|
// When receiving a Steward-message with ACK enabled we send a message back the the
|
|
// node where the message originated using the msg.Reply subject field of the nats-message.
|
|
//
|
|
// With NACK messages we do not send a nats reply message, so the message will only be
|
|
// sent from the publisher once, and if it is not delivered it will not be retried.
|
|
switch {
|
|
|
|
// Check for ACK type Event.
|
|
case p.subject.Event == EventACK:
|
|
// Look up the method handler for the specified method.
|
|
mh, ok := p.methodsAvailable.CheckIfExists(message.Method)
|
|
if !ok {
|
|
er := fmt.Errorf("error: subscriberHandler: no such method type: %v", p.subject.Event)
|
|
p.processes.errorKernel.errSend(p, message, er)
|
|
}
|
|
|
|
out := []byte{}
|
|
var err error
|
|
|
|
if p.signatures.verifySignature(message) {
|
|
// Call the method handler for the specified method.
|
|
out, err = mh.handler(p, message, thisNode)
|
|
|
|
if err != nil {
|
|
er := fmt.Errorf("error: subscriberHandler: handler method failed: %v", err)
|
|
p.processes.errorKernel.errSend(p, message, er)
|
|
}
|
|
}
|
|
|
|
// Send a confirmation message back to the publisher
|
|
natsConn.Publish(msg.Reply, out)
|
|
|
|
// Check for NACK type Event.
|
|
case p.subject.Event == EventNACK:
|
|
mf, ok := p.methodsAvailable.CheckIfExists(message.Method)
|
|
if !ok {
|
|
er := fmt.Errorf("error: subscriberHandler: method type not available: %v", p.subject.Event)
|
|
p.processes.errorKernel.errSend(p, message, er)
|
|
}
|
|
|
|
if p.signatures.verifySignature(message) {
|
|
|
|
_, err := mf.handler(p, message, thisNode)
|
|
|
|
if err != nil {
|
|
er := fmt.Errorf("error: subscriberHandler: handler method failed: %v", err)
|
|
p.processes.errorKernel.errSend(p, message, er)
|
|
}
|
|
}
|
|
|
|
default:
|
|
er := fmt.Errorf("info: did not find that specific type of event: %#v", p.subject.Event)
|
|
p.processes.errorKernel.infoSend(p, message, er)
|
|
|
|
}
|
|
}
|
|
|
|
// SubscribeMessage will register the Nats callback function for the specified
|
|
// nats subject. This allows us to receive Nats messages for a given subject
|
|
// on a node.
|
|
func (p process) subscribeMessages() *nats.Subscription {
|
|
subject := string(p.subject.name())
|
|
natsSubscription, err := p.natsConn.Subscribe(subject, func(msg *nats.Msg) {
|
|
//_, err := p.natsConn.Subscribe(subject, func(msg *nats.Msg) {
|
|
|
|
// Start up the subscriber handler.
|
|
go p.messageSubscriberHandler(p.natsConn, p.configuration.NodeName, msg)
|
|
})
|
|
if err != nil {
|
|
log.Printf("error: Subscribe failed: %v\n", err)
|
|
return nil
|
|
}
|
|
|
|
return natsSubscription
|
|
}
|
|
|
|
// publishMessages will do the publishing of messages for one single
|
|
// process. The function should be run as a goroutine, and will run
|
|
// as long as the process it belongs to is running.
|
|
func (p process) publishMessages(natsConn *nats.Conn) {
|
|
var once sync.Once
|
|
|
|
var zEnc *zstd.Encoder
|
|
// Prepare a zstd encoder if enabled. By enabling it here before
|
|
// looping over the messages to send below, we can reuse the zstd
|
|
// encoder for all messages.
|
|
switch p.configuration.Compression {
|
|
case "z": // zstd
|
|
// enc, err := zstd.NewWriter(nil, zstd.WithEncoderLevel(zstd.SpeedBestCompression))
|
|
enc, err := zstd.NewWriter(nil)
|
|
if err != nil {
|
|
log.Printf("error: zstd new encoder failed: %v\n", err)
|
|
os.Exit(1)
|
|
}
|
|
zEnc = enc
|
|
defer zEnc.Close()
|
|
|
|
}
|
|
|
|
// Loop and handle 1 message at a time. If some part of the code
|
|
// fails in the loop we should throw an error and use `continue`
|
|
// to jump back here to the beginning of the loop and continue
|
|
// with the next message.
|
|
for {
|
|
|
|
// Wait and read the next message on the message channel, or
|
|
// exit this function if Cancel are received via ctx.
|
|
select {
|
|
case m := <-p.subject.messageCh:
|
|
// Sign the methodArgs, and add the signature to the message.
|
|
m.ArgSignature = p.addMethodArgSignature(m)
|
|
fmt.Printf(" * DEBUG: add signature, fromNode: %v, method: %v, len of signature: %v\n", m.FromNode, m.Method, len(m.ArgSignature))
|
|
|
|
p.publishAMessage(m, zEnc, once, natsConn)
|
|
case <-p.ctx.Done():
|
|
er := fmt.Errorf("info: canceling publisher: %v", p.subject.name())
|
|
//sendErrorLogMessage(p.toRingbufferCh, Node(p.node), er)
|
|
log.Printf("%v\n", er)
|
|
return
|
|
}
|
|
}
|
|
}
|
|
|
|
func (p process) addMethodArgSignature(m Message) []byte {
|
|
argsString := argsToString(m.MethodArgs)
|
|
sign := ed25519.Sign(p.signatures.SignPrivateKey, []byte(argsString))
|
|
|
|
return sign
|
|
}
|
|
|
|
func (p process) publishAMessage(m Message, zEnc *zstd.Encoder, once sync.Once, natsConn *nats.Conn) {
|
|
// Create the initial header, and set values below depending on the
|
|
// various configuration options chosen.
|
|
natsMsgHeader := nats.Header{}
|
|
|
|
// The serialized value of the nats message payload
|
|
var natsMsgPayloadSerialized []byte
|
|
|
|
// encode the message structure into gob binary format before putting
|
|
// it into a nats message.
|
|
// Prepare a gob encoder with a buffer before we start the loop
|
|
switch p.configuration.Serialization {
|
|
case "cbor":
|
|
b, err := cbor.Marshal(m)
|
|
if err != nil {
|
|
er := fmt.Errorf("error: messageDeliverNats: cbor encode message failed: %v", err)
|
|
p.processes.errorKernel.errSend(p, m, er)
|
|
return
|
|
}
|
|
|
|
natsMsgPayloadSerialized = b
|
|
natsMsgHeader["serial"] = []string{p.configuration.Serialization}
|
|
|
|
default:
|
|
var bufGob bytes.Buffer
|
|
gobEnc := gob.NewEncoder(&bufGob)
|
|
err := gobEnc.Encode(m)
|
|
if err != nil {
|
|
er := fmt.Errorf("error: messageDeliverNats: gob encode message failed: %v", err)
|
|
p.processes.errorKernel.errSend(p, m, er)
|
|
return
|
|
}
|
|
|
|
natsMsgPayloadSerialized = bufGob.Bytes()
|
|
}
|
|
|
|
// Get the process name so we can look up the process in the
|
|
// processes map, and increment the message counter.
|
|
pn := processNameGet(p.subject.name(), processKindPublisher)
|
|
m.ID = p.messageID
|
|
|
|
// The compressed value of the nats message payload. The content
|
|
// can either be compressed or in it's original form depening on
|
|
// the outcome of the switch below, and if compression were chosen
|
|
// or not.
|
|
var natsMsgPayloadCompressed []byte
|
|
|
|
// Compress the data payload if selected with configuration flag.
|
|
// The compression chosen is later set in the nats msg header when
|
|
// calling p.messageDeliverNats below.
|
|
switch p.configuration.Compression {
|
|
case "z": // zstd
|
|
natsMsgPayloadCompressed = zEnc.EncodeAll(natsMsgPayloadSerialized, nil)
|
|
natsMsgHeader["cmp"] = []string{p.configuration.Compression}
|
|
|
|
zEnc.Reset(nil)
|
|
|
|
case "g": // gzip
|
|
var buf bytes.Buffer
|
|
gzipW := gzip.NewWriter(&buf)
|
|
_, err := gzipW.Write(natsMsgPayloadSerialized)
|
|
if err != nil {
|
|
log.Printf("error: failed to write gzip: %v\n", err)
|
|
gzipW.Close()
|
|
return
|
|
}
|
|
gzipW.Close()
|
|
|
|
natsMsgPayloadCompressed = buf.Bytes()
|
|
natsMsgHeader["cmp"] = []string{p.configuration.Compression}
|
|
case "": // no compression
|
|
natsMsgPayloadCompressed = natsMsgPayloadSerialized
|
|
|
|
default: // no compression
|
|
// Allways log the error to console.
|
|
er := fmt.Errorf("error: compression type not defined, setting default to zero compression")
|
|
log.Printf("%v\n", er)
|
|
|
|
// We only wan't to send the error message to errorCentral once.
|
|
once.Do(func() {
|
|
p.processes.errorKernel.errSend(p, m, er)
|
|
})
|
|
|
|
natsMsgPayloadCompressed = natsMsgPayloadSerialized
|
|
}
|
|
|
|
// Create the Nats message with headers and payload, and do the
|
|
// sending of the message.
|
|
p.messageDeliverNats(natsMsgPayloadCompressed, natsMsgHeader, natsConn, m)
|
|
|
|
// Signaling back to the ringbuffer that we are done with the
|
|
// current message, and it can remove it from the ringbuffer.
|
|
m.done <- struct{}{}
|
|
|
|
// Increment the counter for the next message to be sent.
|
|
p.messageID++
|
|
|
|
{
|
|
p.processes.active.mu.Lock()
|
|
p.processes.active.procNames[pn] = p
|
|
p.processes.active.mu.Unlock()
|
|
}
|
|
|
|
// // Handle the error.
|
|
// //
|
|
// // NOTE: None of the processes above generate an error, so the the
|
|
// // if clause will never be triggered. But keeping it here as an example
|
|
// // for now for how to handle errors.
|
|
// if err != nil {
|
|
// // Create an error type which also creates a channel which the
|
|
// // errorKernel will send back the action about what to do.
|
|
// ep := errorEvent{
|
|
// //errorType: logOnly,
|
|
// process: p,
|
|
// message: m,
|
|
// errorActionCh: make(chan errorAction),
|
|
// }
|
|
// p.errorCh <- ep
|
|
//
|
|
// // Wait for the response action back from the error kernel, and
|
|
// // decide what to do. Should we continue, quit, or .... ?
|
|
// switch <-ep.errorActionCh {
|
|
// case errActionContinue:
|
|
// // Just log and continue
|
|
// log.Printf("The errAction was continue...so we're continuing\n")
|
|
// case errActionKill:
|
|
// log.Printf("The errAction was kill...so we're killing\n")
|
|
// // ....
|
|
// default:
|
|
// log.Printf("Info: publishMessages: The errAction was not defined, so we're doing nothing\n")
|
|
// }
|
|
// }
|
|
}
|