overhaul error handling

tlhunter · Jan 7, 2023 · 8b6300d · 8b6300d
1 parent 434bf74
commit 8b6300d
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Showing 15 changed files with 201 additions and 221 deletions.
diff --git a/README.md b/README.md
@@ -11,7 +11,6 @@
 
 `mig` isn't yet ready for production. When it is `mig` will hit version 1.0. Some of the required tasks to reach this include:
 
-- [ ] document all exit status codes, ensure all errors return non-zero
 - [ ] unit test everything
 - [ ] add support for sqlite
 - [ ] support JSON output via `--json`

diff --git a/commands/all.go b/commands/all.go
@@ -1,7 +1,7 @@
 package commands
 
 import (
-	"os"
+	"errors"
 
 	"github.com/fatih/color"
 
@@ -11,40 +11,38 @@ import (
 )
 
 func CommandAll(cfg config.MigConfig) error {
-	dbox := database.Connect(cfg.Connection)
+	dbox, err := database.Connect(cfg.Connection)
+
+	if err != nil {
+		return err
+	}
 
 	defer dbox.Db.Close()
 
 	// First call to GetStatus is mostly unused. if it fails then don't continue.
 	status, err := migrations.GetStatus(cfg, dbox)
 
 	if err != nil {
-		color.Red("Encountered an error trying to get migrations status!\n")
-		os.Stderr.WriteString(err.Error() + "\n")
-		return err
+		return errors.New("Encountered an error trying to get migrations status!")
 	}
 
 	if status.Skipped > 0 {
-		color.Red("Refusing to run with skipped migrations! Run `mig status` for details.\n")
-		return nil
+		return errors.New("Refusing to run with skipped migrations! Run `mig status` for details.")
 	}
 
 	if status.Next == "" {
-		color.Red("There are no migrations to run.")
-		return nil
+		return errors.New("There are no migrations to run.")
 	}
 
 	locked, err := database.ObtainLock(dbox)
 
 	if err != nil {
-		color.Red("Error obtaining lock for running migrations!\n")
-		os.Stderr.WriteString(err.Error() + "\n")
+		color.Red("Error obtaining lock for running migrations!")
 		return err
 	}
 
 	if !locked {
-		color.Red("Unable to obtain lock for running migrations!\n")
-		return nil
+		return errors.New("Unable to obtain lock for running migrations!")
 	}
 
 	highest, err := migrations.GetHighestValues(dbox)
@@ -66,8 +64,7 @@ func CommandAll(cfg config.MigConfig) error {
 		queries, err := migrations.GetQueriesFromFile(filename)
 
 		if err != nil {
-			color.Red("Error attempting to read next migration file!\n")
-			os.Stderr.WriteString(err.Error() + "\n")
+			color.Red("Error attempting to read next migration file!")
 			return err
 		}
 
@@ -82,35 +79,31 @@ func CommandAll(cfg config.MigConfig) error {
 		_, err = dbox.Db.Exec(query)
 
 		if err != nil {
-			color.Red("Encountered an error while running migration!\n")
-			os.Stderr.WriteString(err.Error() + "\n")
+			color.Red("Encountered an error while running migration!")
 			return err
 		}
 
-		color.Green("Migration %s was successfully applied!\n", next)
+		color.Green("Migration %s was successfully applied!", next)
 
 		err = migrations.AddMigrationWithBatch(dbox, next, batchId)
 
 		if err != nil {
-			color.Red("The migration query executed but unable to track it in the migrations table!\n")
-			color.White("You may want to manually add it and investigate the error.\n")
-			color.White("Any remaining migrations will not be executed!\n")
-			os.Stderr.WriteString(err.Error() + "\n")
+			color.Red("The migration query executed but unable to track it in the migrations table!")
+			color.White("You may want to manually add it and investigate the error.")
+			color.White("Any remaining migrations will not be executed!")
 			return err
 		}
 	}
 
 	released, err := database.ReleaseLock(dbox)
 
 	if err != nil {
-		color.Red("Error releasing lock for migration!\n")
-		os.Stderr.WriteString(err.Error() + "\n")
+		color.Red("Error releasing lock for migration!")
 		return err
 	}
 
 	if !released {
-		color.Red("Unable to release lock for migration!\n")
-		return nil
+		return errors.New("Unable to release lock for migration!")
 	}
 
 	return nil

diff --git a/commands/create.go b/commands/create.go
@@ -37,13 +37,15 @@ func CommandCreate(cfg config.MigConfig, name string) error {
 
 	file, err := os.Create(filePath)
 	if err != nil {
+		color.Red("Unable to create migration file!")
 		return err
 	}
 
 	defer file.Close()
 
 	_, err = file.WriteString(TEMPLATE)
 	if err != nil {
+		color.Red("Unable to write to migration file!")
 		return err
 	}
 

diff --git a/commands/dispatch.go b/commands/dispatch.go
@@ -1,66 +1,66 @@
 package commands
 
 import (
-	"os"
+	"errors"
+	"fmt"
 
-	"github.com/fatih/color"
 	"github.com/tlhunter/mig/config"
 )
 
-func Dispatch(cfg config.MigConfig, subcommands []string) {
+func Dispatch(cfg config.MigConfig, subcommands []string) error {
+	var err error
 	if len(subcommands) == 0 {
-		color.White("usage: mig <command>")
-		os.Exit(10)
+		err = errors.New("usage: mig <command>")
 	}
 
 	switch subcommands[0] {
 	case "create":
 		if len(subcommands) >= 2 {
-			CommandCreate(cfg, subcommands[1])
-			return
+			err = CommandCreate(cfg, subcommands[1])
+		} else {
+			err = errors.New("usage: mig create \"<migration name>\"")
 		}
-		color.White("usage: mig create \"<migration name>\"")
-		os.Exit(10)
 
 	case "init":
-		CommandInit(cfg)
+		err = CommandInit(cfg)
 
 	case "lock":
-		CommandLock(cfg)
+		err = CommandLock(cfg)
 
 	case "unlock":
-		CommandUnlock(cfg)
+		err = CommandUnlock(cfg)
 
 	case "list":
 		fallthrough
 	case "ls":
-		CommandList(cfg)
+		err = CommandList(cfg)
 
 	case "status":
-		CommandStatus(cfg)
+		err = CommandStatus(cfg)
 
 	case "up":
-		CommandUp(cfg)
+		err = CommandUp(cfg)
 
 	case "down":
-		CommandDown(cfg)
+		err = CommandDown(cfg)
 
 	case "all":
-		CommandAll(cfg)
+		err = CommandAll(cfg)
 
 	case "upto":
 		if len(subcommands) >= 2 {
-			CommandUpto(cfg, subcommands[1])
-			return
+			err = CommandUpto(cfg, subcommands[1])
+		} else {
+			err = errors.New("usage: mig upto \"<migration name>\"")
 		}
-		color.White("usage: mig upto \"<migration name>\"")
-		os.Exit(10)
 
 	case "version":
-		CommandVersion(cfg)
+		err = CommandVersion(cfg)
 
 	default:
-		color.White("unsupported command %s", subcommands[0])
-		os.Exit(10)
+		err = errors.New(fmt.Sprintf("unsupported command %s", subcommands[0]))
 	}
+
+	return err
+
 }
diff --git a/commands/down.go b/commands/down.go
@@ -1,7 +1,7 @@
 package commands
 
 import (
-	"os"
+	"errors"
 
 	"github.com/fatih/color"
 	"github.com/tlhunter/mig/config"
@@ -10,15 +10,18 @@ import (
 )
 
 func CommandDown(cfg config.MigConfig) error {
-	dbox := database.Connect(cfg.Connection)
+	dbox, err := database.Connect(cfg.Connection)
+
+	if err != nil {
+		return err
+	}
 
 	defer dbox.Db.Close()
 
 	status, err := migrations.GetStatus(cfg, dbox)
 
 	if err != nil {
-		color.Red("Encountered an error trying to get migrations status!\n")
-		os.Stderr.WriteString(err.Error() + "\n")
+		color.Red("Encountered an error trying to get migrations status!")
 		return err
 	}
 
@@ -29,24 +32,21 @@ func CommandDown(cfg config.MigConfig) error {
 	queries, err := migrations.GetQueriesFromFile(filename)
 
 	if err != nil {
-		color.Red("Error attempting to read last migration file!\n")
-		color.White("Normally a missing migration file isn't a big deal but it's a no go for migrating down.\n")
-		color.White("This file is required before continuing. Perhaps it can be pulled from version control?\n")
-		os.Stderr.WriteString(err.Error() + "\n")
+		color.Red("Error attempting to read last migration file!")
+		color.White("Normally a missing migration file isn't a big deal but it's a no go for migrating down.")
+		color.White("This file is required before continuing. Perhaps it can be pulled from version control?")
 		return err
 	}
 
 	locked, err := database.ObtainLock(dbox)
 
 	if err != nil {
-		color.Red("Error obtaining lock for migrating down!\n")
-		os.Stderr.WriteString(err.Error() + "\n")
+		color.Red("Error obtaining lock for migrating down!")
 		return err
 	}
 
 	if !locked {
-		color.Red("Unable to obtain lock for migrating down!\n")
-		return nil
+		return errors.New("Unable to obtain lock for migrating down!")
 	}
 
 	var query string
@@ -60,33 +60,29 @@ func CommandDown(cfg config.MigConfig) error {
 	_, err = dbox.Db.Exec(query)
 
 	if err != nil {
-		color.Red("Encountered an error while running down migration!\n")
-		os.Stderr.WriteString(err.Error() + "\n")
+		color.Red("Encountered an error while running down migration!")
 		return err
 	}
 
-	color.Green("Migration down %s was successfully applied!\n", last.Name)
+	color.Green("Migration down %s was successfully applied!", last.Name)
 
 	err = migrations.RemoveMigration(dbox, last.Name, last.Id)
 
 	if err != nil {
-		color.Red("The migration down query executed but unable to track it in the migrations table!\n")
-		color.White("You may want to manually remove it and investigate the error.\n")
-		os.Stderr.WriteString(err.Error() + "\n")
+		color.Red("The migration down query executed but unable to track it in the migrations table!")
+		color.White("You may want to manually remove it and investigate the error.")
 		return err
 	}
 
 	released, err := database.ReleaseLock(dbox)
 
 	if err != nil {
-		color.Red("Error obtaining lock for down migration!\n")
-		os.Stderr.WriteString(err.Error() + "\n")
+		color.Red("Error obtaining lock for down migration!")
 		return err
 	}
 
 	if !released {
-		color.Red("Unable to obtain lock for down migration!\n")
-		return nil
+		return errors.New("Unable to obtain lock for down migration!")
 	}
 
 	return nil

diff --git a/commands/init.go b/commands/init.go
@@ -36,14 +36,18 @@ INSERT INTO migrations_lock SET ` + "`index`" + ` = 1, is_locked = 0;`,
 )
 
 func CommandInit(cfg config.MigConfig) error {
-	dbox := database.Connect(cfg.Connection)
+	dbox, err := database.Connect(cfg.Connection)
+
+	if err != nil {
+		return err
+	}
 
 	defer dbox.Db.Close()
 
-	_, err := dbox.Exec(INIT)
+	_, err = dbox.Exec(INIT)
 
 	if err != nil {
-		color.Red("error initializing mig!", err)
+		color.Red("error initializing mig!")
 		return err
 	}
 

diff --git a/commands/list.go b/commands/list.go
@@ -11,7 +11,12 @@ import (
 )
 
 func CommandList(cfg config.MigConfig) error {
-	dbox := database.Connect(cfg.Connection)
+	dbox, err := database.Connect(cfg.Connection)
+
+	if err != nil {
+		return err
+	}
+
 	defer dbox.Db.Close()
 
 	status, err := migrations.GetStatus(cfg, dbox)
@@ -20,18 +25,18 @@ func CommandList(cfg config.MigConfig) error {
 		return err
 	}
 
-	color.White("%5s %-48s %5s %-20s %-20s\n", "ID", "Migration", "Batch", "Time of Run", "Note")
+	color.White("%5s %-48s %5s %-20s %-20s", "ID", "Migration", "Batch", "Time of Run", "Note")
 
 	for _, entry := range status.History {
 		switch entry.Status {
 		case "applied":
-			color.Green("%5d %-48s %5d %20s %-20s\n", entry.Migration.Id, entry.Migration.Name, entry.Migration.Batch, entry.Migration.Time.Format(time.RFC3339), "Applied")
+			color.Green("%5d %-48s %5d %20s %-20s", entry.Migration.Id, entry.Migration.Name, entry.Migration.Batch, entry.Migration.Time.Format(time.RFC3339), "Applied")
 		case "skipped":
-			color.Red("%5s %-48s %5s %20s %-20s\n", "", entry.Migration.Name, "", "", "Migration Skipped!")
+			color.Red("%5s %-48s %5s %20s %-20s", "", entry.Migration.Name, "", "", "Migration Skipped!")
 		case "missing":
-			color.Yellow("%5d %-48s %5d %20s %-20s\n", entry.Migration.Id, entry.Migration.Name, entry.Migration.Batch, entry.Migration.Time.Format(time.RFC3339), "Missing File!")
+			color.Yellow("%5d %-48s %5d %20s %-20s", entry.Migration.Id, entry.Migration.Name, entry.Migration.Batch, entry.Migration.Time.Format(time.RFC3339), "Missing File!")
 		case "unapplied":
-			color.Cyan("%5s %-48s %5s %20s %-20s\n", "", entry.Migration.Name, "", "", "Ready to Run")
+			color.Cyan("%5s %-48s %5s %20s %-20s", "", entry.Migration.Name, "", "", "Ready to Run")
 		}
 	}