Write README for connect client

connectClient/README.md

+# xxdk Connect Client Example
+
+This mini-repository contains the example logic for running a basic connection
+client. This is provided by the xx network team as a springboard to
+help consumers better understand our API and how it may be used.
+
+`main.go` contains the crux of the logic. We avoid complicating our example by
+avoiding the usage of CLI flags for basic variables you may change in the code.
+This file initiates an xxdk E2E client. With that established, a connection 
+client is built on top. Using a precanned contact object created in 
+`connectServer` this connection client contacts the server with a simple 
+message.
+
+`utils.go` contains utility functions for running the program. In this case,
+we provide a tool initializing a log.
+
+`listener.go` contains logic for handling the reception of a message via the
+established connection. In this example, it is very basic. We invite consumers
+to use this as a basis to implement more complex message listeners here.
+
+## Build Instructions
+
+In these instructions we will go over building a connection client using our
+example. In order to build a client which successfully sends a message through
+the connection, we must first go over how to build and run a connection server.
+
+### Building a Server
+
+In order to run a server, the following commands may be run:
+
+```bash
+cd connectServer/
+go build -o server .
+./server
+```
+
+This will initialize the server. You may verify its functionality by checking
+the `server.log`file. It is a long-running process which may be
+stopped by a user inputted kill signal. This will create a file
+`connectServer.xxc`, which is the contat file for the server. A connection
+client may parse this file in order to send a request to this server.
+
+### Building a Client
+
+Please follow the steps above before continuing to these instructions.
+In order to run the client, you must first move the aforementioned
+`connectServer.xxc` file to the path where you will run the client.
+
+```bash
+cd connectServer/
+cp connectServer.xxc /path/to/connectClient
+```
+
+Once the contact object is local to the client, you may build and run
+the client:
+
+```bash
+cd connectClient/
+go build -o client .
+./client 
+```
+
+This is a long-running process which may be stopped by a user inputted kill
+signal. We recommend allowing the process to run for a long enough time to
+complete its requests to the server and receive the server's responses. We go
+into detail on what this entails below.
+
+Once the connection client has set up and established its connection with the
+server, you can verify by checking the server's log for the string 
+`Message received`.
+
+```bash
+ grep "Message received" server.log 
+INFO 2022/07/07 12:59:12.088046 Message received: {XxMessage WjdMwCH+... [73 102 32 116 104 105 115 32 109 101 115 115 97 103 101 32 105 115 32 115 101 110 116 32 115 117 99 99 101 115 115 102 117 108 108 121 44 32 119 101 39 108 108 32 104 97 118 101 32 101 115 116 97 98 108 105 115 104 101 100 32 99 111 110 116 97 99 116 32 119 105 116 104 32 116 104 101 32 115 101 114 118 101 114 46] kuycotVTjefJ4nZWJ+Ksg9/jviANn6suteW6HPmXroID l74No/qjr/8Q74mA9VadudforXet8OykqSvPIEFAeUQD [0 0 0 0 0 2 245 150] 2022-07-07 12:59:07.078570118 -0700 PDT true {58339144 QUEUED 0xc001e12780 map[PENDING:1969-12-31 16:00:01.65722394 -0800 PST PRECOMPUTING:2022-07-07 12:59:00.644730058 -0700 PDT STANDBY:2022-07-07 12:59:07.062879269 -0700 PDT QUEUED:2022-07-07 12:59:10.062881354 -0700 PDT] [] 1000 18 187058678 ID:58339144  UpdateID:187058678  State:3  BatchSize:1000  Topology:"3\xdd\xc9;\xce\xc5\xf0\xff&\x8c\xf1\x7f\nf\xa8K\x17\xb6\xd1\x0b|a\t[\x14\x8e\xde\xd1qϊB\x02"  Topology:"\xf5\\\x94MB\x19ڣq݃\xbee\x99\xbfF\xb5\xa9\xf3k\x0e8 gl\xf5:d\x11\xab\x89\x17\x02"  Topology:"\x01\xc1\xf6Gi\x972p\xa9\x96\xb4\x12\x0f1\x1c\xebw\xef\xca\xed\"F\xa7w\xe2\n\xbb8\xcbd\x05=\x02"  Topology:"\xd5\xc3\xd00\xa3a;RqDs\xf0\xda<\xa3)$y\xef\xc1\xa0\x12_k?\x00\rIebL\xfe\x02"  Topology:"vQ\xcd\t\xaf\x91ڤ\x86\x8ecl\x84\xb1\x95\x1e\x8f+ږQ\\ﷀ]7\x89\x08\x02"  Timestamps:1657223940  Timestamps:1657223940644730058  Timestamps:1657223947062879269  Timestamps:1657223950062881354  Timestamps:0  Timestamps:0  Timestamps:0  ResourceQueueTimeoutMillis:3906340864  AddressSpaceSize:18  EccSignature:{Nonce:"\xb2y\xccf\x86E\xe0NR\xd2J3|\xb8d\xfe\xb3\xa8\xad\xa2\x92\xe0\xe4\x0bZ\x07\xbeٓ\xb4z\xf2"  Signature:"\xe1\xc9 \x92_\xfe\x9d\x7f\x18\xb920C \xa6\xd1\xe9U\xbb\x93o\x9b\x1bp<Y\xb1\x9f\xb7O\x012^^\x9doa\x06P\x83\xfes\xbf\xe1\xaeL\xb0+\\\xdc\x12r4)\xdas49\xf6=\xd2\x13\xa0\x07"}}}
+```
+
+By default, the client sends a single message to the server, with the server
+registering a `receive.Listener` which listens to messages of type 
+`catalog.NoType` from the client. The server does not send a message back in 
+this example. 
+

connectServer/go.mod

@@ -4,7 +4,7 @@ go 1.17
 
 require (
 	github.com/spf13/jwalterweatherman v1.1.0
-	gitlab.com/elixxir/client v1.5.1-0.20220705214402-3ebd3c1fcfec
+	gitlab.com/elixxir/client v1.5.1-0.20220707193810-ed09e1277c6d
 	gitlab.com/elixxir/crypto v0.0.7-0.20220606201132-c370d5039cea
 	gitlab.com/xx_network/primitives v0.0.4-0.20220630163313-7890038258c6
 )

connectServer/go.sum

@@ -253,8 +253,8 @@ github.com/zeebo/pcg v0.0.0-20181207190024-3cdc6b625a05/go.mod h1:Gr+78ptB0MwXxm
 github.com/zeebo/pcg v1.0.0/go.mod h1:09F0S9iiKrwn9rlI5yjLkmrug154/YRW6KnnXVDM/l4=
 gitlab.com/elixxir/bloomfilter v0.0.0-20211222005329-7d931ceead6f h1:yXGvNBqzZwAhDYlSnxPRbgor6JWoOt1Z7s3z1O9JR40=
 gitlab.com/elixxir/bloomfilter v0.0.0-20211222005329-7d931ceead6f/go.mod h1:H6jztdm0k+wEV2QGK/KYA+MY9nj9Zzatux/qIvDDv3k=
-gitlab.com/elixxir/client v1.5.1-0.20220705214402-3ebd3c1fcfec h1:TpO05QgOP3sa0V3KGhOWy6k80YYCvpH/I6/hgwVcpxY=
-gitlab.com/elixxir/client v1.5.1-0.20220705214402-3ebd3c1fcfec/go.mod h1:GCevkp2aa+vpIsSrlF/HsRlTjf107jgCglZ/0JKqW7E=
+gitlab.com/elixxir/client v1.5.1-0.20220707193810-ed09e1277c6d h1:MxseLDnuqGkrnlDDzlH7AYlfm6qPDfy2wf2Qlt4AZbQ=
+gitlab.com/elixxir/client v1.5.1-0.20220707193810-ed09e1277c6d/go.mod h1:GCevkp2aa+vpIsSrlF/HsRlTjf107jgCglZ/0JKqW7E=
 gitlab.com/elixxir/comms v0.0.4-0.20220603231314-e47e4af13326 h1:Zid8oNHtbOqF6ebrcGIccvIMabFNGh9dzY1b7mgIcF0=
 gitlab.com/elixxir/comms v0.0.4-0.20220603231314-e47e4af13326/go.mod h1:tlHSrtSliKWUxsck8z/Ql/VJkMdSONV2BeWaUAAXzgk=
 gitlab.com/elixxir/crypto v0.0.0-20200804182833-984246dea2c4/go.mod h1:ucm9SFKJo+K0N2GwRRpaNr+tKXMIOVWzmyUD0SbOu2c=

connectServer/main.go

@@ -9,6 +9,8 @@ import (
 	"io/fs"
 	"io/ioutil"
 	"os"
+	"os/signal"
+	"syscall"
 	"time"
 
 	"gitlab.com/elixxir/client/connect"
@@ -16,7 +18,7 @@ import (
 
 func main() {
 	// Logging
-	initLog(1, "client.log")
+	initLog(1, "server.log")
 
 	// Create a new client object-------------------------------------------------------
 
@@ -153,5 +155,17 @@ func main() {
 
 	// Keep app running to receive messages-----------------------------------------------
 
-	select {}
+	// Wait until the user terminates the program
+	c := make(chan os.Signal)
+	signal.Notify(c, os.Interrupt, syscall.SIGTERM)
+	<-c
+
+	err = connectServer.E2e.StopNetworkFollower()
+	if err != nil {
+		jww.ERROR.Printf("Failed to stop network follower: %+v", err)
+	} else {
+		jww.INFO.Printf("Stopped network follower.")
+	}
+
+	os.Exit(0)
 }