path: root/rpc/subscription_test.go

// Copyright 2016 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.

package rpc

import (
    "encoding/json"
    "fmt"
    "net"
    "strings"
    "testing"
    "time"
)

func TestNewID(t *testing.T) {
    hexchars := "0123456789ABCDEFabcdef"
    for i := 0; i < 100; i++ {
        id := string(NewID())
        if !strings.HasPrefix(id, "0x") {
            t.Fatalf("invalid ID prefix, want '0x...', got %s", id)
        }

        id = id[2:]
        if len(id) == 0 || len(id) > 32 {
            t.Fatalf("invalid ID length, want len(id) > 0 && len(id) <= 32), got %d", len(id))
        }

        for i := 0; i < len(id); i++ {
            if strings.IndexByte(hexchars, id[i]) == -1 {
                t.Fatalf("unexpected byte, want any valid hex char, got %c", id[i])
            }
        }
    }
}

func TestSubscriptions(t *testing.T) {
    var (
        namespaces        = []string{"eth", "shh", "bzz"}
        service           = &notificationTestService{}
        subCount          = len(namespaces)
        notificationCount = 3

        server                 = NewServer()
        clientConn, serverConn = net.Pipe()
        out                    = json.NewEncoder(clientConn)
        in                     = json.NewDecoder(clientConn)
        successes              = make(chan subConfirmation)
        notifications          = make(chan subscriptionResult)
        errors                 = make(chan error, subCount*notificationCount+1)
    )

    // setup and start server
    for _, namespace := range namespaces {
        if err := server.RegisterName(namespace, service); err != nil {
            t.Fatalf("unable to register test service %v", err)
        }
    }
    go server.ServeCodec(NewJSONCodec(serverConn), OptionMethodInvocation|OptionSubscriptions)
    defer server.Stop()

    // wait for message and write them to the given channels
    go waitForMessages(in, successes, notifications, errors)

    // create subscriptions one by one
    for i, namespace := range namespaces {
        request := map[string]interface{}{
            "id":      i,
            "method":  fmt.Sprintf("%s_subscribe", namespace),
            "version": "2.0",
            "params":  []interface{}{"someSubscription", notificationCount, i},
        }
        if err := out.Encode(&request); err != nil {
            t.Fatalf("Could not create subscription: %v", err)
        }
    }

    timeout := time.After(30 * time.Second)
    subids := make(map[string]string, subCount)
    count := make(map[string]int, subCount)
    allReceived := func() bool {
        done := len(count) == subCount
        for _, c := range count {
            if c < notificationCount {
                done = false
            }
        }
        return done
    }
    for !allReceived() {
        select {
        case confirmation := <-successes: // subscription created
            subids[namespaces[confirmation.reqid]] = string(confirmation.subid)
        case notification := <-notifications:
            count[notification.ID]++
        case err := <-errors:
            t.Fatal(err)
        case <-timeout:
            for _, namespace := range namespaces {
                subid, found := subids[namespace]
                if !found {
                    t.Errorf("subscription for %q not created", namespace)
                    continue
                }
                if count, found := count[subid]; !found || count < notificationCount {
                    t.Errorf("didn't receive all notifications (%d<%d) in time for namespace %q", count, notificationCount, namespace)
                }
            }
            t.Fatal("timed out")
        }
    }
}

// This test checks that unsubscribing works.
func TestServerUnsubscribe(t *testing.T) {
    // Start the server.
    server := newTestServer()
    service := &notificationTestService{unsubscribed: make(chan string)}
    server.RegisterName("nftest2", service)
    p1, p2 := net.Pipe()
    go server.ServeCodec(NewJSONCodec(p1), OptionMethodInvocation|OptionSubscriptions)

    p2.SetDeadline(time.Now().Add(10 * time.Second))

    // Subscribe.
    p2.Write([]byte(`{"jsonrpc":"2.0","id":1,"method":"nftest2_subscribe","params":["someSubscription",0,10]}`))

    // Handle received messages.
    resps := make(chan subConfirmation)
    notifications := make(chan subscriptionResult)
    errors := make(chan error)
    go waitForMessages(json.NewDecoder(p2), resps, notifications, errors)

    // Receive the subscription ID.
    var sub subConfirmation
    select {
    case sub = <-resps:
    case err := <-errors:
        t.Fatal(err)
    }

    // Unsubscribe and check that it is handled on the server side.
    p2.Write([]byte(`{"jsonrpc":"2.0","method":"nftest2_unsubscribe","params":["` + sub.subid + `"]}`))
    for {
        select {
        case id := <-service.unsubscribed:
            if id != string(sub.subid) {
                t.Errorf("wrong subscription ID unsubscribed")
            }
            return
        case err := <-errors:
            t.Fatal(err)
        case <-notifications:
            // drop notifications
        }
    }
}

type subConfirmation struct {
    reqid int
    subid ID
}

func waitForMessages(in *json.Decoder, successes chan subConfirmation, notifications chan subscriptionResult, errors chan error) {
    for {
        var msg jsonrpcMessage
        if err := in.Decode(&msg); err != nil {
            errors <- fmt.Errorf("decode error: %v", err)
            return
        }
        switch {
        case msg.isNotification():
            var res subscriptionResult
            if err := json.Unmarshal(msg.Params, &res); err != nil {
                errors <- fmt.Errorf("invalid subscription result: %v", err)
            } else {
                notifications <- res
            }
        case msg.isResponse():
            var c subConfirmation
            if msg.Error != nil {
                errors <- msg.Error
            } else if err := json.Unmarshal(msg.Result, &c.subid); err != nil {
                errors <- fmt.Errorf("invalid response: %v", err)
            } else {
                json.Unmarshal(msg.ID, &c.reqid)
                successes <- c
            }
        default:
            errors <- fmt.Errorf("unrecognized message: %v", msg)
            return
        }
    }
}