chore(examples): add pubsub example with production env (#1333)

* chore(examples): add pubsub example with production env

* chore(examples): fix comments 1/2

* chore(examples): fix comments 2/2

examples/v2/README.md

@@ -0,0 +1,34 @@
+# basic2
+
+TODO
+
+# publisher/subscriber
+
+Within `examples/v2` you can find a `publisher` and a `subscriber`. The first one publises messages to the default pubsub topic to a given content topic, and the second one runs forever listening to that pubsub topic and printing the content it receives.
+
+**Some notes:**
+* These examples are meant to work even in if you are behind a firewall and you can't be discovered by discv5.
+* You only need to provide a reachable bootstrap peer (see our [fleets](https://fleets.status.im/))
+* The examples are meant to work out of the box.
+* Note that both services wait for some time until a given minimum amount of connections are reached. This is to ensure messages are gossiped.
+
+**Compile:**
+
+Make all examples.
+```console
+make example2
+```
+
+**Run:**
+
+Wait until the subscriber is ready.
+```console
+./build/subscriber
+```
+
+And run a publisher
+```console
+./build/publisher
+```
+
+See how the subscriber received the messages published by the publisher. Feel free to experiment from different machines in different locations.

examples/v2/basic2.nim

@@ -5,6 +5,7 @@ import
   std/[os,options],
   confutils, chronicles, chronos,
   stew/shims/net as stewNet,
+  stew/byteutils,
   libp2p/crypto/[crypto,secp],
   eth/keys,
   json_rpc/[rpcclient, rpcserver],
@@ -29,7 +30,7 @@ proc runBackground() {.async.} =
   await node.mountRelay()
 
   # Subscribe to a topic
-  let topic = cast[PubsubTopic]("foobar")
+  let topic = PubsubTopic("foobar")
   proc handler(topic: PubsubTopic, data: seq[byte]) {.async, gcsafe.} =
     let message = WakuMessage.init(data).value
     let payload = cast[string](message.payload)
@@ -37,7 +38,7 @@ proc runBackground() {.async.} =
   node.subscribe(topic, handler)
 
   # Publish to a topic
-  let payload = cast[seq[byte]]("hello world")
+  let payload = toBytes("hello world")
   let message = WakuMessage(payload: payload, contentTopic: ContentTopic("/waku/2/default-content/proto"))
   await node.publish(topic, message)
 

examples/v2/publisher.nim

@@ -0,0 +1,88 @@
+import
+  std/[tables,times,sequtils],
+  stew/byteutils,
+  stew/shims/net,
+  chronicles,
+  chronicles/topics_registry,
+  chronos,
+  confutils,
+  libp2p/crypto/crypto,
+  eth/keys,
+  eth/p2p/discoveryv5/enr
+
+import
+  ../../../waku/v2/node/discv5/waku_discv5,
+  ../../../waku/v2/node/peer_manager/peer_manager,
+  ../../../waku/v2/node/waku_node,
+  ../../../waku/v2/protocol/waku_message,
+  ../../../waku/v2/utils/time,
+  ../../../waku/v2/utils/wakuenr
+
+proc now*(): Timestamp =
+  getNanosecondTime(getTime().toUnixFloat())
+
+# An accesible bootstrap node. See wakuv2.prod fleets.status.im
+const bootstrapNodes = @["enr:-Nm4QOdTOKZJKTUUZ4O_W932CXIET-M9NamewDnL78P5u9DOGnZlK0JFZ4k0inkfe6iY-0JAaJVovZXc575VV3njeiABgmlkgnY0gmlwhAjS3ueKbXVsdGlhZGRyc7g6ADg2MW5vZGUtMDEuYWMtY24taG9uZ2tvbmctYy53YWt1djIucHJvZC5zdGF0dXNpbS5uZXQGH0DeA4lzZWNwMjU2azGhAo0C-VvfgHiXrxZi3umDiooXMGY9FvYj5_d1Q4EeS7eyg3RjcIJ2X4N1ZHCCIyiFd2FrdTIP"]
+
+# careful if running pub and sub in the same machine
+const wakuPort = 60000
+const discv5Port = 9000
+
+proc setupAndPublish() {.async.} =
+    # use notice to filter all waku messaging
+    setLogLevel(LogLevel.NOTICE)
+    notice "starting publisher", wakuPort=wakuPort, discv5Port=discv5Port
+    let
+        nodeKey = crypto.PrivateKey.random(Secp256k1, crypto.newRng()[])[]
+        ip = ValidIpAddress.init("0.0.0.0")
+        node = WakuNode.new(nodeKey, ip, Port(wakuPort))
+        flags = initWakuFlags(lightpush = false, filter = false, store = false, relay = true)
+    
+    # assumes behind a firewall, so not care about being discoverable
+    node.wakuDiscv5 = WakuDiscoveryV5.new(
+        extIp= none(ValidIpAddress),
+        extTcpPort = none(Port),
+        extUdpPort = none(Port),
+        bindIP = ip,
+        discv5UdpPort = Port(discv5Port),
+        bootstrapNodes = bootstrapNodes,
+        privateKey = keys.PrivateKey(nodeKey.skkey),
+        flags = flags,
+        enrFields = [],
+        rng = node.rng)
+
+    await node.start()
+    await node.mountRelay()
+    if not await node.startDiscv5():
+      error "failed to start discv5"
+      quit(1)
+
+    # wait for a minimum of peers to be connected, otherwise messages wont be gossiped
+    while true:
+      let numConnectedPeers = node.peerManager.peerStore.connectionBook.book.values().countIt(it == Connected)
+      if numConnectedPeers >= 6:
+        notice "publisher is ready", connectedPeers=numConnectedPeers, required=6
+        break
+      notice "waiting to be ready", connectedPeers=numConnectedPeers, required=6
+      await sleepAsync(5000)
+
+    # Make sure it matches the publisher. Use default value
+    # see spec: https://rfc.vac.dev/spec/23/
+    let pubSubTopic = PubsubTopic("/waku/2/default-waku/proto")
+
+    # any content topic can be chosen
+    let contentTopic = ContentTopic("/examples/1/pubsub-example/proto")
+
+    notice "publisher service started"
+    while true:
+      let text = "hi there i'm a publisher"
+      let message = WakuMessage(payload: toBytes(text), # content of the message
+                                contentTopic: contentTopic,     # content topic to publish to
+                                ephemeral: true,                # tell store nodes to not store it
+                                timestamp: now())               # current timestamp
+      await node.publish(pubSubTopic, message)
+      notice "published message", text = text, timestamp = message.timestamp, psTopic = pubSubTopic, contentTopic = contentTopic
+      await sleepAsync(5000)
+
+asyncSpawn setupAndPublish()
+runForever()

examples/v2/subscriber.nim

@@ -0,0 +1,84 @@
+import
+  std/[tables, sequtils],
+  stew/byteutils,
+  stew/shims/net,
+  chronicles,
+  chronicles/topics_registry,
+  chronos,
+  confutils,
+  libp2p/crypto/crypto,
+  eth/keys,
+  eth/p2p/discoveryv5/enr
+
+import
+  ../../../waku/v2/node/discv5/waku_discv5,
+  ../../../waku/v2/node/peer_manager/peer_manager,
+  ../../../waku/v2/node/waku_node,
+  ../../../waku/v2/protocol/waku_message,
+  ../../../waku/v2/utils/wakuenr
+
+# An accesible bootstrap node. See wakuv2.prod fleets.status.im
+const bootstrapNodes = @["enr:-Nm4QOdTOKZJKTUUZ4O_W932CXIET-M9NamewDnL78P5u9DOGnZlK0JFZ4k0inkfe6iY-0JAaJVovZXc575VV3njeiABgmlkgnY0gmlwhAjS3ueKbXVsdGlhZGRyc7g6ADg2MW5vZGUtMDEuYWMtY24taG9uZ2tvbmctYy53YWt1djIucHJvZC5zdGF0dXNpbS5uZXQGH0DeA4lzZWNwMjU2azGhAo0C-VvfgHiXrxZi3umDiooXMGY9FvYj5_d1Q4EeS7eyg3RjcIJ2X4N1ZHCCIyiFd2FrdTIP"]
+
+# careful if running pub and sub in the same machine
+const wakuPort = 50000
+const discv5Port = 8000
+
+proc setupAndSubscribe() {.async.} =
+    # use notice to filter all waku messaging
+    setLogLevel(LogLevel.NOTICE)
+    notice "starting subscriber", wakuPort=wakuPort, discv5Port=discv5Port
+    let
+        nodeKey = crypto.PrivateKey.random(Secp256k1, crypto.newRng()[])[]
+        ip = ValidIpAddress.init("0.0.0.0")
+        node = WakuNode.new(nodeKey, ip, Port(wakuPort))
+        flags = initWakuFlags(lightpush = false, filter = false, store = false, relay = true)
+
+    # assumes behind a firewall, so not care about being discoverable
+    node.wakuDiscv5 = WakuDiscoveryV5.new(
+        extIp= none(ValidIpAddress),
+        extTcpPort = none(Port),
+        extUdpPort = none(Port),
+        bindIP = ip,
+        discv5UdpPort = Port(discv5Port),
+        bootstrapNodes = bootstrapNodes,
+        privateKey = keys.PrivateKey(nodeKey.skkey),
+        flags = flags,
+        enrFields = [],
+        rng = node.rng)
+
+    await node.start()
+    await node.mountRelay()
+    if not await node.startDiscv5():
+      error "failed to start discv5"
+      quit(1)
+
+    # wait for a minimum of peers to be connected, otherwise messages wont be gossiped
+    while true:
+      let numConnectedPeers = node.peerManager.peerStore.connectionBook.book.values().countIt(it == Connected)
+      if numConnectedPeers >= 6:
+        notice "subscriber is ready", connectedPeers=numConnectedPeers, required=6
+        break
+      notice "waiting to be ready", connectedPeers=numConnectedPeers, required=6
+      await sleepAsync(5000)
+
+    # Make sure it matches the publisher. Use default value
+    # see spec: https://rfc.vac.dev/spec/23/
+    let pubSubTopic = PubsubTopic("/waku/2/default-waku/proto")
+
+    # any content topic can be chosen. make sure it matches the publisher
+    let contentTopic = ContentTopic("/examples/1/pubsub-example/proto")
+
+    proc handler(pubsubTopic: PubsubTopic, data: seq[byte]) {.async, gcsafe.} =
+      let message = WakuMessage.init(data).value
+      let payloadStr = string.fromBytes(message.payload)
+      if message.contentTopic == contentTopic:
+        notice "message received", payload=payloadStr,
+                                   pubsubTopic=pubsubTopic,
+                                   contentTopic=message.contentTopic,
+                                   timestamp=message.timestamp
+    node.subscribe(pubSubTopic, handler)
+
+asyncSpawn setupAndSubscribe()
+
+runForever()

waku.nimble

@@ -81,8 +81,9 @@ task sim2, "Build Waku v2 simulation tools":
   buildBinary "start_network2", "tools/simulation/", "-d:chronicles_log_level=TRACE"
 
 task example2, "Build Waku v2 example":
-  let name = "basic2"
-  buildBinary name, "examples/v2/", "-d:chronicles_log_level=DEBUG"
+  buildBinary "basic2", "examples/v2/", "-d:chronicles_log_level=DEBUG"
+  buildBinary "publisher", "examples/v2/", "-d:chronicles_log_level=DEBUG"
+  buildBinary "subscriber", "examples/v2/", "-d:chronicles_log_level=DEBUG"
 
 task scripts2, "Build Waku v2 scripts":
   buildBinary "rpc_publish", "tools/scripts/", "-d:chronicles_log_level=DEBUG"
@@ -103,7 +104,6 @@ task chat2bridge, "Build chat2bridge":
   let name = "chat2bridge"
   buildBinary name, "apps/chat2bridge/", "-d:chronicles_log_level=TRACE"
 
-
 ### Waku Tooling
 task wakucanary, "Build waku-canary tool":
   let name = "wakucanary"