refactor: get rid of olekukonko/tablewriter package (#20)

cmd/repl/main.go → cmd/shell/main.go

@@ -2,13 +2,11 @@ package main
 
 import (
 	"context"
-	"errors"
-	"log"
 	"os"
 	"os/signal"
 	"syscall"
 
-	"github.com/i-sevostyanov/NanoDB/internal/repl"
+	"github.com/i-sevostyanov/NanoDB/internal/shell"
 	"github.com/i-sevostyanov/NanoDB/internal/sql/engine"
 	"github.com/i-sevostyanov/NanoDB/internal/sql/parsing/ast"
 	"github.com/i-sevostyanov/NanoDB/internal/sql/parsing/lexer"
@@ -21,22 +19,17 @@ func main() {
 	ctx, cancel := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
 	defer cancel()
 
-	parseFn := engine.ParseFn(func(sql string) (ast.Node, error) {
+	sqlParser := engine.ParseFn(func(sql string) (ast.Node, error) {
 		lx := lexer.New(sql)
 		pr := parser.New(lx)
 		return pr.Parse()
 	})
 
-	catalog := memory.NewCatalog()
-	aPlanner := planner.New(catalog)
-	anEngine := engine.New(parseFn, aPlanner)
-	aRepl := repl.New(os.Stdin, os.Stdout, catalog, anEngine)
+	sqlCatalog := memory.NewCatalog()
+	sqlPlanner := planner.New(sqlCatalog)
+	sqlEngine := engine.New(sqlParser, sqlPlanner)
+	tableWriter := shell.NewTableWriterFactory()
 
-	if err := aRepl.Run(ctx); err != nil {
-		switch {
-		case errors.Is(err, repl.ErrQuit):
-		default:
-			log.Printf("repl: %v\n", err)
-		}
-	}
+	sh := shell.New(os.Stdin, os.Stdout, sqlCatalog, sqlEngine, tableWriter)
+	sh.Run(ctx)
 }

go.mod

@@ -3,16 +3,13 @@ module github.com/i-sevostyanov/NanoDB
 go 1.22
 
 require (
-	github.com/olekukonko/tablewriter v0.0.5
 	github.com/stretchr/testify v1.9.0
 	go.uber.org/mock v0.4.0
 )
 
 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
-	github.com/mattn/go-runewidth v0.0.15 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
-	github.com/rivo/uniseg v0.4.7 // indirect
 	golang.org/x/mod v0.17.0 // indirect
 	golang.org/x/tools v0.21.0 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect

go.sum

@@ -1,15 +1,7 @@
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/mattn/go-runewidth v0.0.9/go.mod h1:H031xJmbD/WCDINGzjvQ9THkh0rPKHF+m2gUSrubnMI=
-github.com/mattn/go-runewidth v0.0.15 h1:UNAjwbU9l54TA3KzvqLGxwWjHmMgBUVhBiTjelZgg3U=
-github.com/mattn/go-runewidth v0.0.15/go.mod h1:Jdepj2loyihRzMpdS35Xk/zdY8IAYHsh153qUoGf23w=
-github.com/olekukonko/tablewriter v0.0.5 h1:P2Ga83D34wi1o9J6Wh1mRuqd4mF/x/lgBS7N7AbDhec=
-github.com/olekukonko/tablewriter v0.0.5/go.mod h1:hPp6KlRPjbx+hW8ykQs1w3UBbZlj6HuIJcUGPhkA7kY=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
-github.com/rivo/uniseg v0.2.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
-github.com/rivo/uniseg v0.4.7 h1:WUdvkW8uEhrYfLC4ZzdpI2ztxP1I582+49Oc5Mq64VQ=
-github.com/rivo/uniseg v0.4.7/go.mod h1:FN3SvrM+Zdj16jyLfmOkMNblXMcoc8DfTHruCPUcx88=
 github.com/stretchr/testify v1.9.0 h1:HtqpIVDClZ4nwg75+f6Lvsy/wHu+3BoSGCbBAcpTsTg=
 github.com/stretchr/testify v1.9.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
 go.uber.org/mock v0.4.0 h1:VcM4ZOtdbR4f6VXfiOpwpVJDL6lCReaZ6mw31wqh7KU=

internal/repl/repl.go → internal/shell/shell.go

@@ -1,4 +1,4 @@
-package repl
+package shell
 
 import (
 	"bufio"
@@ -8,129 +8,130 @@ import (
 	"fmt"
 	"io"
 	"os"
+	"strconv"
 	"strings"
 
 	"github.com/i-sevostyanov/NanoDB/internal/sql"
-
-	"github.com/olekukonko/tablewriter"
 )
 
 const prompt = "#> "
 
-var ErrQuit = errors.New("quit")
+type TableWriter interface {
+	WriteTable(w io.Writer, headers []string, data [][]string, showRowsCount bool)
+}
 
 type Engine interface {
 	Exec(database, sql string) (columns []string, iter sql.RowIter, err error)
 }
 
-// Repl is terminal-based front-end to NanoDB.
-type Repl struct {
+// Shell is terminal-based front-end to NanoDB.
+type Shell struct {
 	input    io.Reader
 	output   io.Writer
 	catalog  sql.Catalog
 	database sql.Database
 	engine   Engine
+	tw       TableWriter
 	prompt   string
 	closeCh  chan struct{}
 }
 
-func New(in io.Reader, out io.Writer, catalog sql.Catalog, engine Engine) *Repl {
-	return &Repl{
+func New(in io.Reader, out io.Writer, catalog sql.Catalog, engine Engine, tw TableWriter) *Shell {
+	return &Shell{
 		input:   in,
 		output:  out,
 		catalog: catalog,
 		engine:  engine,
+		tw:      tw,
 		prompt:  prompt,
 		closeCh: make(chan struct{}),
 	}
 }
 
-func (r *Repl) Run(ctx context.Context) error {
-	r.write("repl is the NanoDB interactive terminal.\n")
+func (s *Shell) Run(ctx context.Context) {
+	s.write("shell is the NanoDB interactive terminal.\n")
 
 	go func() {
 		for {
-			r.write(r.prompt)
+			s.write(s.prompt)
 
-			scanner := bufio.NewScanner(r.input)
+			scanner := bufio.NewScanner(s.input)
 			scanner.Scan()
 			input := scanner.Text()
 
 			if input == "" {
 				continue
 			}
 
-			if repl, err := r.exec(input); err != nil {
-				r.write(err.Error() + "\n")
+			if repl, err := s.exec(input); err != nil {
+				s.write(err.Error() + "\n")
 			} else if repl != "" {
-				r.write(repl)
+				s.write(repl)
 			}
 		}
 	}()
 
 	select {
 	case <-ctx.Done():
-		return nil
-	case <-r.closeCh:
-		return ErrQuit
+	case <-s.closeCh:
 	}
 }
 
-func (r *Repl) write(s string) {
-	_, _ = r.output.Write([]byte(s))
+func (s *Shell) write(line string) {
+	_, _ = s.output.Write([]byte(line))
 }
 
-func (r *Repl) exec(input string) (string, error) {
+func (s *Shell) exec(input string) (string, error) {
 	switch input[0] {
 	case '\\':
-		return r.execCommand(input)
+		return s.execCommand(input)
 	default:
-		return r.execQuery(input)
+		return s.execQuery(input)
 	}
 }
 
-func (r *Repl) execCommand(input string) (string, error) {
+func (s *Shell) execCommand(input string) (string, error) {
 	cmd := strings.TrimSpace(input)
 	params := strings.Fields(cmd)
 
 	switch params[0] {
 	case `\use`:
-		return r.useDatabase(params)
+		return s.useDatabase(params)
 	case `\databases`:
-		return r.listDatabases()
+		return s.listDatabases()
 	case `\tables`:
-		return r.listTables()
+		return s.listTables()
 	case `\describe`:
-		return r.describeTable(params)
+		return s.describeTable(params)
 	case `\import`:
-		return r.importFile(params)
+		return s.importFile(params)
 	case `\help`:
-		return r.showHelp(), nil
+		return s.showHelp(), nil
 	case `\quit`:
-		return r.quit(), nil
+		return s.quit(), nil
 	default:
 		return "", fmt.Errorf("unknown command: %v", params[0])
 	}
 }
 
-func (r *Repl) useDatabase(params []string) (string, error) {
+func (s *Shell) useDatabase(params []string) (string, error) {
 	if len(params) < 2 {
 		return "", fmt.Errorf("database name not specified")
 	}
 
-	db, err := r.catalog.GetDatabase(params[1])
+	db, err := s.catalog.GetDatabase(params[1])
 	if err != nil {
 		return "", err
 	}
 
-	r.database = db
-	r.prompt = fmt.Sprintf("%s %s", db.Name(), prompt)
+	s.database = db
+	s.prompt = fmt.Sprintf("%s %s", db.Name(), prompt)
 
 	return "database changed\n", nil
 }
 
-func (r *Repl) listDatabases() (string, error) {
-	databases, err := r.catalog.ListDatabases()
+func (s *Shell) listDatabases() (string, error) {
+	databases, err := s.catalog.ListDatabases()
 	if err != nil {
 		return "", err
 	}
@@ -142,41 +143,39 @@ func (r *Repl) listDatabases() (string, error) {
 		data = append(data, []string{databases[i].Name()})
 	}
 
-	r.drawTable(buf, []string{"Database"}, data)
-	buf.WriteString(fmt.Sprintf("(%d rows)\n\n", len(data)))
+	s.tw.WriteTable(buf, []string{"Database"}, data, true)
 
 	return buf.String(), nil
 }
 
-func (r *Repl) listTables() (string, error) {
-	if r.database == nil {
+func (s *Shell) listTables() (string, error) {
+	if s.database == nil {
 		return "", fmt.Errorf("connect to database first")
 	}
 
 	buf := bytes.NewBuffer(nil)
-	tables := r.database.ListTables()
+	tables := s.database.ListTables()
 	data := make([][]string, 0, len(tables))
 
 	for i := range tables {
 		data = append(data, []string{tables[i].Name()})
 	}
 
-	r.drawTable(buf, []string{"Table"}, data)
-	buf.WriteString(fmt.Sprintf("(%d rows)\n\n", len(data)))
+	s.tw.WriteTable(buf, []string{"Table"}, data, true)
 
 	return buf.String(), nil
 }
 
-func (r *Repl) describeTable(params []string) (string, error) {
-	if r.database == nil {
+func (s *Shell) describeTable(params []string) (string, error) {
+	if s.database == nil {
 		return "", fmt.Errorf("connect to database first")
 	}
 
 	if len(params) < 2 {
 		return "", fmt.Errorf("table name not specified")
 	}
 
-	table, err := r.database.GetTable(params[1])
+	table, err := s.database.GetTable(params[1])
 	if err != nil {
 		return "", err
 	}
@@ -209,21 +208,21 @@ func (r *Repl) describeTable(params []string) (string, error) {
 		row := []string{
 			columns[i].Name,
 			columns[i].DataType.String(),
-			fmt.Sprintf("%t", columns[i].Nullable),
+			strconv.FormatBool(columns[i].Nullable),
 			defaultValue,
 		}
 
 		data = append(data, row)
 	}
 
-	r.drawTable(buf, []string{"Column", "Type", "Nullable", "Default"}, data)
+	s.tw.WriteTable(buf, []string{"Column", "Type", "Nullable", "Default"}, data, false)
 	buf.WriteString("Indexes:\n")
 	buf.WriteString(fmt.Sprintf("   PRIMARY KEY (%s) autoincrement\n\n", primaryKey.Name))
 
 	return buf.String(), nil
 }
 
-func (r *Repl) importFile(params []string) (string, error) {
+func (s *Shell) importFile(params []string) (string, error) {
 	if len(params) < 2 {
 		return "", fmt.Errorf("filename not specified")
 	}
@@ -241,15 +240,15 @@ func (r *Repl) importFile(params []string) (string, error) {
 			continue
 		}
 
-		if _, err = r.exec(stmt); err != nil {
+		if _, err = s.exec(stmt); err != nil {
 			return "", err
 		}
 	}
 
 	return "OK\n", nil
 }
 
-func (r *Repl) showHelp() string {
+func (s *Shell) showHelp() string {
 	help := `repl is the NanoDB interactive terminal.
 
 Commands:
@@ -264,19 +263,19 @@ Commands:
 	return help
 }
 
-func (r *Repl) quit() string {
-	close(r.closeCh)
+func (s *Shell) quit() string {
+	close(s.closeCh)
 	return "Bye!\n"
 }
 
-func (r *Repl) execQuery(input string) (string, error) {
+func (s *Shell) execQuery(input string) (string, error) {
 	var database string
 
-	if r.database != nil {
-		database = r.database.Name()
+	if s.database != nil {
+		database = s.database.Name()
 	}
 
-	columns, rowIter, err := r.engine.Exec(database, input)
+	columns, rowIter, err := s.engine.Exec(database, input)
 	if err != nil {
 		return "", fmt.Errorf("failed to execute query: %w", err)
 	}
@@ -311,19 +310,8 @@ loop:
 	buf := bytes.NewBuffer(nil)
 
 	if len(data) > 0 {
-		r.drawTable(buf, columns, data)
-		buf.WriteString(fmt.Sprintf("(%d rows)\n\n", len(data)))
+		s.tw.WriteTable(buf, columns, data, true)
 	}
 
 	return buf.String(), nil
 }
-
-func (r *Repl) drawTable(w io.Writer, headers []string, data [][]string) {
-	tw := tablewriter.NewWriter(w)
-	tw.SetColWidth(75)
-	tw.AppendBulk(data)
-	tw.SetAutoFormatHeaders(false)
-	tw.SetAlignment(tablewriter.ALIGN_LEFT)
-	tw.SetHeader(headers)
-	tw.Render()
-}