Resolves #8 , #9 - Introduces command structure and help command.

cmd/main.go

@@ -2,10 +2,39 @@ package main
 
 import (
 	"fmt"
+	"github.com/elasticpath/epcc-cli/external/command"
+	"github.com/elasticpath/epcc-cli/external/help"
 	_ "github.com/elasticpath/epcc-cli/external/resources"
+	"os"
 )
 
+var commands = []command.Command{
+	help.Command,
+}
+
 func main() {
-	fmt.Printf("Hello %s", "World!")
+	argsWithoutProg := os.Args[1:]
+
+	if (len(argsWithoutProg)) == 0 {
+		fmt.Printf("No command specified")
+		os.Exit(1)
+	}
+
+	commandToRun := argsWithoutProg[0]
+
+	cmds := make(map[string]command.Command)
+
+	for _, cmd := range commands {
+		cmds[cmd.Keyword] = cmd
+	}
+
+	for _, cmd := range commands {
+		if cmd.Keyword == commandToRun {
+			argsWithoutCmd := argsWithoutProg[1:]
+			os.Exit(cmd.Execute(cmds, argsWithoutCmd))
+		}
+	}
 
+	fmt.Printf("Unknown command %s specified", commandToRun)
+	os.Exit(0)
 }

cmd/main_test.go

@@ -0,0 +1,15 @@
+package main
+
+import "testing"
+
+func TestNoDuplicateCommands(t *testing.T) {
+	set := make(map[string]bool)
+
+	for _, command := range commands {
+		set[command.Keyword] = true
+	}
+
+	if len(set) != len(commands) {
+		t.Fatalf("Duplicate commands have been registered since the length of the keyword set is not the same as the array")
+	}
+}

external/command/command.go

@@ -0,0 +1,10 @@
+package command
+
+type Command struct {
+	// The keyword the command should use
+	Keyword string
+	// A one-line description of the command
+	Description string
+	// The function that will be executed
+	Execute func(cmds map[string]Command, args []string) int
+}

external/help/help.go

@@ -0,0 +1,44 @@
+package help
+
+import (
+	"fmt"
+	"github.com/elasticpath/epcc-cli/external/command"
+	"sort"
+)
+
+var Command = command.Command{
+	Keyword:     "help",
+	Description: "Displays this screen",
+	Execute: func(cmds map[string]command.Command, args []string) int {
+
+		keys := make([]string, 0, len(cmds))
+		for k := range cmds {
+			keys = append(keys, k)
+		}
+		sort.Strings(keys)
+
+		fmt.Printf(`
+Setup
+
+The EPCC CLI tool uses environment variables for configuration and in particular a tool like https://direnv.net/ which
+auto populates your shell with environment variables when you switch directories. This allows you to store a context in a folder,
+and come back to it at any time.
+
+Environment Variables
+
+- EPCC_API_BASE_URL - The API endpoint that we will hit
+- EPCC_CLIENT_ID - The client id (available in Commerce Manager)
+- EPCC_CLIENT_SECRET - The client secret (available in Commerce Manager)
+- EPCC_BETA_API_FEATURES - Beta features in the API we want to enable.
+
+The following commands are supported:
+
+`)
+
+		for _, key := range keys {
+			fmt.Printf("  %s - %s", cmds[key].Keyword, cmds[key].Description)
+		}
+
+		return 0
+	},
+}

external/resources/resources.go

@@ -2,7 +2,6 @@ package resources
 
 import (
 	_ "embed"
-	"fmt"
 	"gopkg.in/yaml.v3"
 )
 
@@ -18,9 +17,6 @@ func init() {
 		panic("Couldn't load the resource meta data")
 	}
 
-	// You can delete this line later.
-	fmt.Printf("Loaded data for %d resources: ", len(Resources))
-
 	for key, val := range Resources {
 		// Fix the key
 		val.Type = key
@@ -29,13 +25,7 @@ func init() {
 			// Fix the key
 			attributeVal.Key = attributeName
 		}
-
-		// Delete me later
-		fmt.Printf("%s,", key)
 	}
-
-	// Delete me later
-	fmt.Print("\n")
 }
 
 type Resource struct {