From 5c0e3401f47f4928b07b03640bec7af74a53e64f Mon Sep 17 00:00:00 2001
From: Erik Brakkee <erik@brakkee.org>
Date: Tue, 23 Jul 2024 21:51:48 +0200
Subject: [PATCH] command-line argument parsing with error handling for all
 commands that are referred to on the docs page.

---
 Dockerfile             |  2 +-
 cmd/agent/agent.go     | 28 +++++++++++++++++++++++-----
 cmd/converge/server.go |  2 +-
 cmd/tcptows/tcptows.go |  7 +++++++
 cmd/wsproxy/proxy.go   | 18 ++++++++++++++++++
 5 files changed, 50 insertions(+), 7 deletions(-)

diff --git a/Dockerfile b/Dockerfile
index 9e5ea05..724ee2d 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -21,4 +21,4 @@ COPY --from=builder /opt/converge/bin/agent \
                     /opt/converge/docs/
 COPY --from=builder /opt/converge/static/ /opt/converge/docs/
 
-ENTRYPOINT ["/opt/converge/bin/converge", "-docsdir", "/opt/converge/docs" ]
+ENTRYPOINT ["/opt/converge/bin/converge", "-d", "/opt/converge/docs" ]
diff --git a/cmd/agent/agent.go b/cmd/agent/agent.go
index 9082cd4..fa2de8a 100755
--- a/cmd/agent/agent.go
+++ b/cmd/agent/agent.go
@@ -6,6 +6,7 @@ import (
 	"converge/pkg/iowrappers"
 	"converge/pkg/terminal"
 	"converge/pkg/websocketutil"
+	"flag"
 	"fmt"
 	"github.com/gliderlabs/ssh"
 	"github.com/gorilla/websocket"
@@ -133,12 +134,29 @@ func (f ReaderFunc) Read(p []byte) (n int, err error) {
 }
 
 func main() {
-	wsURL := os.Args[1]
 
-	advanceWarningTime := 5 * time.Minute
-	agentExpriryTime := 10 * time.Minute
-	tickerInterval := 60 * time.Second
-	agent.ConfigureAgent(advanceWarningTime, agentExpriryTime, tickerInterval)
+	usage := "agent [options] <wsUrl> \n" +
+		"\n" +
+		"Run agent with <wsUrl> of the form ws[s]://<host>[:port]/agent/<ID>\n" +
+		"Here <ID> is the unique id of the agent that allows rendez-vous with an end-user.\n" +
+		"The end-user must specify the same id when connecting using ssh.\n"
+
+	flag.Usage = func() {
+		fmt.Fprintf(os.Stderr, usage+"\n")
+		flag.PrintDefaults()
+	}
+	advanceWarningTime := flag.Duration("warning-time", 5*time.Minute, "advance warning time before sessio ends")
+	agentExpriryTime := flag.Duration("expiry-time", 10*time.Minute, "expiry time of the session")
+	tickerInterval := flag.Duration("check-interval", 60*time.Second, "interval at which expiry is checked")
+
+	flag.Parse()
+	if flag.NArg() != 1 {
+		flag.Usage()
+		os.Exit(1)
+	}
+	wsURL := flag.Arg(0)
+
+	agent.ConfigureAgent(*advanceWarningTime, *agentExpriryTime, *tickerInterval)
 
 	conn, _, err := websocket.DefaultDialer.Dial(wsURL, nil)
 	if err != nil {
diff --git a/cmd/converge/server.go b/cmd/converge/server.go
index bb8463b..32ae113 100644
--- a/cmd/converge/server.go
+++ b/cmd/converge/server.go
@@ -27,7 +27,7 @@ func catchAllHandler(w http.ResponseWriter, r *http.Request) {
 }
 
 func main() {
-	downloadOption := flag.String("docsdir", "downloads",
+	downloadOption := flag.String("d", "downloads",
 		"directory where documentation is located, either relative to current directory or an absolute path")
 
 	flag.Usage = func() {
diff --git a/cmd/tcptows/tcptows.go b/cmd/tcptows/tcptows.go
index fa8a6c3..0ef0d68 100644
--- a/cmd/tcptows/tcptows.go
+++ b/cmd/tcptows/tcptows.go
@@ -3,6 +3,7 @@ package main
 import (
 	"converge/pkg/iowrappers"
 	"converge/pkg/websocketutil"
+	"fmt"
 	"github.com/gorilla/websocket"
 	"log"
 	"net"
@@ -35,6 +36,12 @@ func handleConnection(conn net.Conn, wsURL string) {
 }
 
 func main() {
+	if len(os.Args) != 3 {
+		fmt.Fprintln(os.Stderr, "Usage: tcptows <localport> ws[s]://<host>[:port]/client/<ID>")
+		fmt.Fprintln(os.Stderr)
+		fmt.Fprintln(os.Stderr, "Here <ID> is the rendez-vous id of a continuous integratio job")
+		os.Exit(1)
+	}
 	tcpPort := os.Args[1]
 	wsURL := os.Args[2]
 
diff --git a/cmd/wsproxy/proxy.go b/cmd/wsproxy/proxy.go
index abb4c1b..6c754e0 100644
--- a/cmd/wsproxy/proxy.go
+++ b/cmd/wsproxy/proxy.go
@@ -3,6 +3,7 @@ package main
 import (
 	"converge/pkg/iowrappers"
 	"converge/pkg/websocketutil"
+	"fmt"
 	"github.com/gorilla/websocket"
 	"log"
 	"net"
@@ -27,9 +28,26 @@ func (stdio Stdio) Write(b []byte) (n int, err error) {
 }
 
 func main() {
+	if len(os.Args) != 2 {
+		fmt.Fprintln(os.Stderr, "Usage: tcptows ws[s]://<host>[:port]/client/<ID>")
+		fmt.Fprintln(os.Stderr)
+		fmt.Fprintln(os.Stderr, "Here <ID> is the rendez-vous id of a continuous integratio job")
+		fmt.Fprintln(os.Stderr, "Use this in an ssh command like this; ")
+		fmt.Fprintln(os.Stderr)
+		fmt.Fprintln(os.Stderr, "  ssh -oProxyCommand='wsproxy ws[s]://<host>[:port]/client/<ID>' abc@localhost")
+		fmt.Fprintln(os.Stderr)
+		fmt.Fprintln(os.Stderr, "This lets ssh connect through wsproxy to the remote websocket on")
+		fmt.Fprintln(os.Stderr, "Converge server.")
+		fmt.Fprintln(os.Stderr)
+		os.Exit(1)
+	}
+
 	wsURL := os.Args[1]
 
 	_wsConn, _, err := websocket.DefaultDialer.Dial(wsURL, nil)
+	if err != nil {
+		panic(err)
+	}
 	_wsConn.SetReadDeadline(time.Time{})
 	_wsConn.SetWriteDeadline(time.Time{})
 	if err != nil {