Add package initialization subcommand and package

cmd/main.go

@@ -14,17 +14,17 @@ const (
 )
 
 func main() {
-	rootCmd := &cobra.Command{
+	root_cmd := &cobra.Command{
 		Use:           "gas",
 		SilenceErrors: true,
 		SilenceUsage:  true,
 	}
-	rootCmd.AddCommand(sqlite_lint)
-	if err := rootCmd.Execute(); err != nil {
+	root_cmd.AddCommand(sqlite_lint)
+	root_cmd.AddCommand(cmd_init)
+	if err := root_cmd.Execute(); err != nil {
 		fmt.Println(RED + err.Error() + RESET)
 		os.Exit(1)
 	}
 }
 
-// Subcommand "init"
 // Subcommand "generate_models"

cmd/subcmd_init.go

@@ -0,0 +1,68 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/spf13/cobra"
+
+	"git.offline-twitter.com/offline-labs/gas-stack/pkg/codegen"
+	. "git.offline-twitter.com/offline-labs/gas-stack/pkg/flowutils"
+)
+
+var cmd_init = &cobra.Command{
+	Use:   "init [path]",
+	Short: "Initialize a new project",
+	Long:  "Initialize a new Gas Stack project at the given path.  If no path is given, defaults to current directory.",
+
+	Args: cobra.MaximumNArgs(1),
+
+	Run: func(cmd *cobra.Command, args []string) {
+		var target string
+		if len(args) != 0 {
+			target = args[0]
+			PanicIf(os.MkdirAll(target, 0o755))
+			PanicIf(os.Chdir(target))
+		} else {
+			// Default to current directory (".")
+			target = Must(os.Getwd())
+		}
+
+		// Get all the config values
+		get_val := func(prompt string, val *string) {
+			fmt.Printf("%s (%q): ", prompt, *val)
+			input := ""
+			Must(fmt.Scanln(&input))
+			if input != "" {
+				*val = input
+			}
+		}
+		pkg_opts := codegen.PkgOpts{
+			ModuleName: Must(cmd.Flags().GetString("module")),
+			DBFilename: Must(cmd.Flags().GetString("db")),
+			BinaryName: Must(cmd.Flags().GetString("binary")),
+		}
+		if pkg_opts.ModuleName == "" {
+			pkg_opts.ModuleName = filepath.Base(target)
+			get_val("module name", &pkg_opts.ModuleName)
+		}
+		if pkg_opts.DBFilename == "" {
+			pkg_opts.DBFilename = pkg_opts.ModuleName + ".db"
+			get_val("db name", &pkg_opts.DBFilename)
+		}
+		if pkg_opts.BinaryName == "" {
+			pkg_opts.BinaryName = pkg_opts.ModuleName
+			get_val("binary name", &pkg_opts.BinaryName)
+		}
+
+		// Run project initialization
+		codegen.InitPkg(pkg_opts)
+	},
+}
+
+func init() {
+	cmd_init.Flags().String("module", "", "Module name")
+	cmd_init.Flags().String("db", "", "Database filename")
+	cmd_init.Flags().String("binary", "", "Binary name")
+}

pkg/codegen/pkg.go

@@ -0,0 +1,51 @@
+package codegen
+
+import (
+	"embed"
+	"fmt"
+	"os"
+	"os/exec"
+
+	. "git.offline-twitter.com/offline-labs/gas-stack/pkg/flowutils"
+)
+
+//go:embed "tpl"
+var tpl embed.FS
+
+type PkgOpts struct {
+	ModuleName string
+	DBFilename string
+	BinaryName string
+}
+
+func InitPkg(opts PkgOpts) {
+	// Run `go mod init`
+	fmt.Printf("Running...  `go mod init %s`\n", opts.ModuleName)
+	PanicIf(exec.Command("go", "mod", "init", opts.ModuleName).Run())
+
+	// Run `git init`, if required
+	if exec.Command("git", "status").Run() != nil {
+		// Not in a git repo yet; init one
+		fmt.Println("Running...  `git init`")
+		PanicIf(exec.Command("git", "init").Run())
+	}
+
+	// Create package structure
+	PanicIf(os.MkdirAll("pkg/db", 0o755))
+	PanicIf(os.MkdirAll("cmd", 0o755))
+	PanicIf(os.MkdirAll("doc", 0o755))
+	PanicIf(os.MkdirAll("sample_data", 0o755))
+
+	PanicIf(os.WriteFile("pkg/db/schema.sql", Must(tpl.ReadFile("tpl/schema.sql")), 0o664))
+
+	PanicIf(os.WriteFile("sample_data/mount.sh", Must(tpl.ReadFile("tpl/mount.sh")), 0o775))
+	PanicIf(os.WriteFile("sample_data/reset.sh", Must(tpl.ReadFile("tpl/reset.sh")), 0o775))
+	PanicIf(os.WriteFile("pkg/db/schema.sql", Must(tpl.ReadFile("tpl/schema.sql")), 0o664))
+
+	// TODO:
+	// - create `pkg/db/errors.go`
+	// - create `sample_data/seed.sql`
+	// - create `sample_data/data/`
+	// - create `.gitignore`
+	// - do something with `db_setup.go` (should go in Gas Stack `pkg/db`)
+}

pkg/codegen/tpl/mount.sh

@@ -0,0 +1,3 @@
+#!/bin/bash
+
+sudo mount -t tmpfs -o size=100M tmpfs sample_data/data

pkg/codegen/tpl/reset.sh

@@ -0,0 +1,6 @@
+#!/usr/bin/env bash
+
+rm sample_data/data/* || true
+
+go run ./cmd init
+sqlite3 sample_data/data/{{ .DBFilename }} < sample_data/seed.sql

pkg/codegen/tpl/schema.sql

@@ -0,0 +1,10 @@
+PRAGMA foreign_keys = on;
+
+-- =======
+-- DB meta
+-- =======
+
+create table db_version (
+    version integer not null
+) strict;
+insert into db_version values(0);