Add main program with 'sqlite_lint' subcommand

cmd/main.go

@@ -0,0 +1,30 @@
+package main
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/spf13/cobra"
+)
+
+const (
+	GREEN = "\033[0;32m"
+	RED   = "\033[0;31m"
+	RESET = "\033[0m"
+)
+
+func main() {
+	rootCmd := &cobra.Command{
+		Use:           "gas",
+		SilenceErrors: true,
+		SilenceUsage:  true,
+	}
+	rootCmd.AddCommand(sqlite_lint)
+	if err := rootCmd.Execute(); err != nil {
+		fmt.Println(RED + err.Error() + RESET)
+		os.Exit(1)
+	}
+}
+
+// Subcommand "init"
+// Subcommand "generate_models"

cmd/subcmd_sqlite_lint.go

@@ -0,0 +1,79 @@
+package main
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/spf13/cobra"
+
+	"git.offline-twitter.com/offline-labs/gas-stack/pkg/schema"
+	"git.offline-twitter.com/offline-labs/gas-stack/pkg/schema/lint"
+)
+
+var sqlite_lint = &cobra.Command{
+	Use:   "sqlite_lint <path/to/schema.sql>",
+	Short: "Lint a SQLite schema",
+
+	Args: func(cmd *cobra.Command, args []string) error {
+		if len(args) != 1 {
+			return errors.New("required: filepath as first argument")
+		}
+		return nil
+	},
+
+	Run: func(rootCmd *cobra.Command, args []string) {
+		filename := args[0]
+		fmt.Printf("-----------------\nLinting %s\n", filename)
+		schema, err := schema.SchemaFromSQLFile(args[0])
+		if err != nil {
+			fmt.Println(err)
+			os.Exit(1)
+		}
+
+		is_failure := false
+		// Execute each check against the database
+		for _, check := range lint.Checks {
+			// Checks can be disabled via Github config / environment variables
+			if !is_check_enabled(check) {
+				continue
+			}
+			results := check.Execute(schema)
+
+			// If there are results, print them as lint errors
+			if len(results) > 0 {
+				is_failure = true
+				fmt.Printf(RED+"Check '%s' failed:\n"+RESET, check.Name)
+				for _, result := range results {
+					fmt.Printf(RED+"- %s: %s.%s\n"+RESET, result.ErrorMsg, result.TableName, result.ColumnName)
+				}
+				fmt.Printf(RED+"Explanation: %s\n\n"+RESET, check.Explanation)
+			}
+		}
+		if is_failure {
+			fmt.Println(RED + "Errors found" + RESET)
+			os.Exit(1)
+		}
+		fmt.Println(GREEN + "Success" + RESET)
+	},
+}
+
+// github_actions_input_env_var converts an input name to the corresponding
+// environment variable name used by GitHub Actions.
+func github_actions_input_env_var(name string) string {
+	// GitHub normalizes both hyphens and underscores to underscores, then uppercases the name
+	normalized := strings.NewReplacer("-", "_", " ", "_").Replace(name)
+	return "INPUT_" + strings.ToUpper(normalized)
+}
+
+// Setting the environment variable INPUT_REQUIRE_NOT_NULL="false" disables the "require_not_null" check
+func is_check_enabled(c lint.Check) bool {
+	val, is_set := os.LookupEnv(github_actions_input_env_var(c.Name))
+	if !is_set {
+		// Enable all checks by default
+		return true
+	}
+	// Anything except "false" is true
+	return val != "false"
+}