From 3787bedfeafbf748f9881931ec69ce885899d029 Mon Sep 17 00:00:00 2001
From: Brian Buller <brian@bullercodeworks.com>
Date: Mon, 25 Jan 2016 11:46:13 -0600
Subject: [PATCH] Initial Commit

---
 cmd/main.go |  84 +++++++++++++++++++++++++++++++++++
 gosyphus.go | 123 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 207 insertions(+)
 create mode 100644 cmd/main.go
 create mode 100644 gosyphus.go

diff --git a/cmd/main.go b/cmd/main.go
new file mode 100644
index 0000000..7c4d9ff
--- /dev/null
+++ b/cmd/main.go
@@ -0,0 +1,84 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"os/user"
+	"strings"
+
+	"gogs.bullercodeworks.com/brian/gosyphus"
+)
+
+func main() {
+	var proc string
+	if len(os.Args) > 1 {
+		// The first argument is the executable that we want to serve
+		proc = os.Args[1]
+	}
+	cwd, err := os.Getwd()
+	wd := cwd
+	wd = requestParam("Working Directory", wd, true)
+	for !checkFileExists(proc) {
+		if len(proc) > 0 {
+			fmt.Println("Couldn't find file: " + proc)
+		}
+		proc = requestParam("Process", proc, true)
+	}
+	if !strings.HasPrefix(proc, "/") {
+		proc = cwd + "/" + proc
+	}
+	var userName string
+	user, err := user.Current()
+	if err == nil {
+		userName = user.Name
+	}
+	userName = requestParam("Username", userName, true)
+	groupName := requestParam("Group Name", userName, true)
+	//desc := requestParam("Description", "", false)
+	outFile := requestParam("Output File", "", true)
+	if !strings.HasSuffix(outFile, ".service") {
+		outFile = outFile + ".service"
+	}
+	// TODO: Request Environment
+	/*
+		environ := os.Environ()
+		for i := range environ {
+			fmt.Println(environ[i])
+		}
+	*/
+	g := gosyphus.NewService(wd, proc, userName, groupName)
+	//g.Describe(desc)
+	g.GenerateFile(outFile)
+}
+
+func requestParam(label, def string, req bool) string {
+	var firstRun = true
+	var newVal string
+	for firstRun || (req && len(newVal) == 0) {
+		fmt.Print(label)
+		fmt.Print(" [")
+		outDef := def
+		if len(outDef) == 0 {
+			outDef = "No default"
+		}
+		fmt.Print(outDef)
+		fmt.Print("]: ")
+		fmt.Scanf("%s", &newVal)
+		if len(newVal) == 0 {
+			newVal = def
+		}
+		firstRun = false
+	}
+	return newVal
+}
+
+func checkFileExists(fn string) bool {
+	_, err := os.Stat(fn)
+	if err == nil {
+		return true
+	}
+	if os.IsNotExist(err) {
+		return false
+	}
+	return true
+}
diff --git a/gosyphus.go b/gosyphus.go
new file mode 100644
index 0000000..1288503
--- /dev/null
+++ b/gosyphus.go
@@ -0,0 +1,123 @@
+package gosyphus
+
+import (
+	"os"
+	"strings"
+)
+
+// Gosyphus represents a Systemd service
+type Gosyphus struct {
+	servType    string
+	description string
+	user        string
+	group       string
+	directory   string
+	process     string
+	restart     bool
+	needNetwork bool
+	environment map[string]string
+	wantedBy    string
+}
+
+// NewService creates a service
+func NewService(wd, proc, usr, grp string) *Gosyphus {
+	g := &Gosyphus{
+		servType:    "simple",
+		directory:   wd,
+		process:     proc,
+		user:        usr,
+		group:       grp,
+		restart:     true,
+		needNetwork: true,
+		wantedBy:    "multi-user.target",
+	}
+	g.environment = make(map[string]string)
+	return g
+}
+
+// Describe sets the description of the service
+func (g *Gosyphus) Describe(desc string) {
+	g.description = desc
+}
+
+// DisableNetwork removes the network requirement from the service
+func (g *Gosyphus) DisableNetwork() {
+	g.needNetwork = false
+}
+
+// EnableNetwork adds the network requirement to the service
+func (g *Gosyphus) EnableNetwork() {
+	g.needNetwork = true
+}
+
+// DisableRestart sets the 'Restart' flag to 'never'
+func (g *Gosyphus) DisableRestart() {
+	g.restart = false
+}
+
+// EnableRestart sets the 'Restart' flag to 'always'
+func (g *Gosyphus) EnableRestart() {
+	g.restart = true
+}
+
+// AddToEnvironment adds a new line to the service environment
+func (g *Gosyphus) AddToEnvironment(k, v string) {
+	g.environment[k] = v
+}
+
+// SetEnvironmentToCurrent copies the active environment into the service
+func (g *Gosyphus) SetEnvironmentToCurrent() {
+	for _, env := range os.Environ() {
+		vars := strings.Split(env, "=")
+		if len(vars) == 2 {
+			g.AddToEnvironment(vars[0], vars[1])
+		}
+	}
+}
+
+// GenerateFile generates the .service file in the current directory
+func (g *Gosyphus) GenerateFile(filename string) error {
+	// For now, we force the USER and HOME environment variables
+	// TODO: make this dynamic
+	g.AddToEnvironment("USER", g.user)
+	g.AddToEnvironment("HOME", "/home/"+g.user)
+
+	f, err := os.OpenFile(filename, os.O_CREATE|os.O_WRONLY, 0664)
+	if err != nil {
+		return err
+	}
+	f.WriteString("[Unit]\n")
+	f.WriteString("Description=" + g.description + "\n")
+	f.WriteString("After=syslog.target\n")
+	if g.needNetwork {
+		f.WriteString("After=network.target\n")
+	}
+	f.WriteString("\n")
+	f.WriteString("[Service]\n")
+	f.WriteString("Type=simple\n")
+	f.WriteString("User=" + g.user + "\n")
+	f.WriteString("Group=" + g.group + "\n")
+	f.WriteString("WorkingDirectory=" + g.directory + "\n")
+	f.WriteString("ExecStart=" + g.process + "\n")
+	if g.restart {
+		f.WriteString("Restart=always\n")
+	} else {
+		f.WriteString("Restart=no\n")
+	}
+	if len(g.environment) > 0 {
+		f.WriteString("Environment=")
+	}
+	var envString string
+	for k, v := range g.environment {
+		envString += ",\"" + k + "=" + v + "\""
+	}
+	if len(envString) > 0 {
+		envString = envString[1:]
+	}
+	f.WriteString(envString)
+	f.WriteString("\n")
+	f.WriteString("[Install]\n")
+	f.WriteString("WantedBy=" + g.wantedBy + "\n")
+	f.Close()
+	return nil
+}
\ No newline at end of file