feat(status): Add status command (#29)

README.md

@@ -32,7 +32,7 @@ files to be saved in (which will be the same directory of the main package, e.g.
 `example`), an instance of `*pg.DB`, and `os.Args`; and log any potential errors
 that could be returned.
 
-Once this has been set up, then you can use the `create`, `migrate`, `rollback`,
+Once this has been set up, then you can use the `create`, `migrate`, `status`, `rollback`,
 `help` commands like so:
 
 ```
@@ -43,6 +43,13 @@ $ go run example/*.go migrate
 Running batch 1 with 1 migration(s)...
 Finished running "20180812001528_create_users_table"
 
+$ go run example/*.go status
++---------+-----------------------------------+-------+
+| Applied | Migration                         | Batch |
++---------+-----------------------------------+-------+
+|    √    | 20180812001528_create_users_table |     1 |
++---------+-----------------------------------+-------+
+
 $ go run example/*.go rollback
 Rolling back batch 1 with 1 migration(s)...
 Finished rolling back "20180812001528_create_users_table"
@@ -55,12 +62,14 @@ Commands:
   create   - create a new migration in example with the provided name
   migrate  - run any migrations that haven't been run yet
   rollback - roll back the previous run batch of migrations
+  status   - show the status of each migration
   help     - print this help text
 
 Examples:
   go run example/*.go create create_users_table
   go run example/*.go migrate
   go run example/*.go rollback
+  go run example/*.go status
   go run example/*.go help
 ```
 

help.go

@@ -9,15 +9,17 @@ Commands:
   create   - create a new migration in %s with the provided name
   migrate  - run any migrations that haven't been run yet
   rollback - roll back the previous run batch of migrations
+  status   - show the status of each migration
   help     - print this help text
 
 Examples:
   go run %s/*.go create create_users_table
   go run %s/*.go migrate
   go run %s/*.go rollback
+  go run %s/*.go status
   go run %s/*.go help
 `
 
 func help(directory string) {
-	fmt.Printf(helpText, directory, directory, directory, directory, directory, directory)
+	fmt.Printf(helpText, directory, directory, directory, directory, directory, directory, directory)
 }

migrations.go

@@ -4,6 +4,7 @@ package migrations
 
 import (
 	"errors"
+	"os"
 	"time"
 
 	"github.com/go-pg/pg/v10"
@@ -72,6 +73,13 @@ func Run(db *pg.DB, directory string, args []string) error {
 		}
 
 		return rollback(db)
+	case "status":
+		err := ensureMigrationTables(db)
+		if err != nil {
+			return err
+		}
+
+		return status(db, os.Stdout)
 	default:
 		help(directory)
 		return nil

status.go

@@ -0,0 +1,82 @@
+package migrations
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"sort"
+	"strings"
+	"unicode/utf8"
+
+	"github.com/go-pg/pg/v10"
+)
+
+type migrationWithStatus struct {
+	migration
+}
+
+func status(db *pg.DB, w io.Writer) error {
+	// sort the registered migrations by name (which will sort by the
+	// timestamp in their names)
+	sort.Slice(migrations, func(i, j int) bool {
+		return migrations[i].Name < migrations[j].Name
+	})
+
+	// look at the migrations table to see the already run migrations
+	completed, err := getCompletedMigrations(db)
+	if err != nil {
+		return err
+	}
+
+	// diff the completed migrations from the registered migrations to find
+	// the migrations we still need to run
+	uncompleted := filterMigrations(migrations, completed, false)
+
+	return writeStatusTable(w, completed, uncompleted)
+}
+
+func writeStatusTable(w io.Writer, completed []migration, uncompleted []migration) error {
+	if len(completed)+len(uncompleted) == 0 {
+		_, err := fmt.Fprintln(w, "No migrations found")
+		return err
+	}
+
+	maxNameLength := 20
+	for _, m := range completed {
+		maxNameLength = maxInt(maxNameLength, utf8.RuneCountInString(m.Name))
+	}
+	for _, m := range uncompleted {
+		maxNameLength = maxInt(maxNameLength, utf8.RuneCountInString(m.Name))
+	}
+
+	bf := bytes.NewBuffer(nil)
+
+	// write header
+	bf.WriteString("+---------+" + strings.Repeat("-", maxNameLength+2) + "+-------+\n")
+	bf.WriteString("| Applied | Migration" + strings.Repeat(" ", maxNameLength-8) + "| Batch |\n")
+	bf.WriteString("+---------+" + strings.Repeat("-", maxNameLength+2) + "+-------+\n")
+
+	// write completed migrations
+	for _, m := range completed {
+		bf.WriteString("|    √    | " + m.Name + strings.Repeat(" ", maxNameLength-len(m.Name)) + " | " + fmt.Sprintf("%5d", m.Batch) + " |\n")
+	}
+
+	// write uncompleted migrations
+	for _, m := range uncompleted {
+		bf.WriteString("|         | " + m.Name + strings.Repeat(" ", maxNameLength-len(m.Name)) + " |       |\n")
+	}
+
+	// write footer
+	bf.WriteString("+---------+" + strings.Repeat("-", maxNameLength+2) + "+-------+\n")
+
+	_, err := bf.WriteTo(w)
+	return err
+}
+
+func maxInt(a, b int) int {
+	if a > b {
+		return a
+	} else {
+		return b
+	}
+}

status_test.go

@@ -0,0 +1,92 @@
+package migrations
+
+import (
+	"bytes"
+	"os"
+	"strings"
+	"testing"
+
+	"github.com/go-pg/pg/v10"
+	"github.com/stretchr/testify/require"
+)
+
+func TestStatus(t *testing.T) {
+	db := pg.Connect(&pg.Options{
+		Addr:     "localhost:5432",
+		User:     os.Getenv("TEST_DATABASE_USER"),
+		Database: os.Getenv("TEST_DATABASE_NAME"),
+	})
+
+	db.AddQueryHook(logQueryHook{})
+
+	err := ensureMigrationTables(db)
+	require.Nil(t, err)
+
+	defer clearMigrations(t, db)
+	defer resetMigrations(t)
+
+	completed := []migration{
+		{Name: "2021_02_26_151503_dump", Up: noopMigration, Down: noopMigration, Batch: 1},
+		{Name: "2021_02_26_151504_create_a_dump_table_for_test", Up: noopMigration, Down: noopMigration, Batch: 2},
+	}
+	uncompleted := []migration{
+		{Name: "2021_02_26_151502_create_2nd_dump_table", Up: noopMigration, Down: noopMigration},
+		{Name: "2021_02_26_151505_create_3rd_dump_table", Up: noopMigration, Down: noopMigration},
+	}
+	expected := strings.TrimSpace(`
++---------+------------------------------------------------+-------+
+| Applied | Migration                                      | Batch |
++---------+------------------------------------------------+-------+
+|    √    | 2021_02_26_151503_dump                         |     1 |
+|    √    | 2021_02_26_151504_create_a_dump_table_for_test |     2 |
+|         | 2021_02_26_151502_create_2nd_dump_table        |       |
+|         | 2021_02_26_151505_create_3rd_dump_table        |       |
++---------+------------------------------------------------+-------+
+`)
+
+	t.Run("status_command", func(tt *testing.T) {
+		clearMigrations(tt, db)
+		resetMigrations(tt)
+
+		migrations = completed[:1]
+		err := migrate(db)
+		require.Nil(tt, err, "migrate: %v", err)
+		migrations = completed[:2]
+		err = migrate(db)
+		require.Nil(tt, err, "migrate: %v", err)
+
+		migrations = append(migrations, uncompleted...)
+		bf := bytes.NewBuffer(nil)
+		err = status(db, bf)
+		require.Nil(tt, err, "status: %v", err)
+
+		got := strings.TrimSpace(bf.String())
+		if got != expected {
+			tt.Errorf("status table not match:\nEXPECTED:\n%s\nACTUAL:\n%s", expected, got)
+		}
+	})
+
+	t.Run("write_status_table", func(tt *testing.T) {
+		bf := bytes.NewBuffer(nil)
+		err := writeStatusTable(bf, completed, uncompleted)
+		require.Nil(tt, err, "write_status_table: %v", err)
+
+		got := strings.TrimSpace(bf.String())
+		if got != expected {
+			tt.Errorf("status table not match:\nEXPECTED:\n%s\nACTUAL:\n%s", expected, got)
+		}
+	})
+
+	t.Run("no_migrations_found", func(tt *testing.T) {
+		expected := strings.TrimSpace(`No migrations found`)
+
+		bf := bytes.NewBuffer(nil)
+		err := writeStatusTable(bf, nil, nil)
+		require.Nil(tt, err, "write_status_table: %v", err)
+
+		got := strings.TrimSpace(bf.String())
+		if got != expected {
+			tt.Errorf("status table not match:\nEXPECTED:\n%s\nACTUAL:\n%s", expected, got)
+		}
+	})
+}