/pkg/integrations/README.md

/pkg/integrations is responsible for exposing state machines over various JSON transports, with currently only NATS being implemented. In the future, this may include email, Kafka, or HTTP.

JSON

JSON types cover mutations, subscriptions, and data getters. Each of these is divided in request and response objects which have a (/docs/jsonschema). Their usage depends on the specific implementation, eg in NATS each machine has a dedicated subtopic for mutation requests.

• MutationReq (jsonschema)
• MutationResp (jsonschema)
• WaitingReq (jsonschema)
• WaitingResp (jsonschema)
• GetterReq (jsonschema)
• GetterResp (jsonschema)

import amjson "github.com/pancsta/asyncmachine-go/pkg/integration"

// create a subscription to Foo
reqSub := integrations.NewWaitingReq()
reqSub.States = am.S{"Foo"}
j, err := json.Marshal(reqSub)

NATS

NATS is a popular and high-performance messaging system made in Go. State machines are exposed under a topic, with each state machine also being subscribed to a dedicated subtopic “[topic].[machineID]” for mutation requests. Optional [queue] allows to load-balance requests across multiple subscribers.

import am "github.com/pancsta/asyncmachine-go"
import nats "github.com/pancsta/asyncmachine-go/pkg/integration/nats"

// ...

// var mach *am.Machine
// var ctx context.Context
// var nc *nats.Conn

// expose mach under mytopic
_ = nats.ExposeMachine(ctx, mach, nc, "mytopic", "")
// mutate - add Foo
res, _ := nats.Add(ctx, nc, topic, mach.Id(), am.S{"Foo"}, nil)
if res == am.Executed {
    print("Foo added to mach")
}

TODO

• recipient matching (filters similar to the REPL ones)
• better error handling (avoid overreporting)

Status

Alpha, work in progress, not semantically versioned.