/
handler.go
1047 lines (875 loc) · 20.1 KB
/
handler.go
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package handler
import (
"bufio"
"bytes"
"database/sql"
"fmt"
"io"
"net/url"
"os"
"os/user"
"path/filepath"
"strconv"
"strings"
"time"
"unicode"
"github.com/alecthomas/chroma"
"github.com/alecthomas/chroma/formatters"
"github.com/alecthomas/chroma/styles"
"github.com/olekukonko/tablewriter"
"github.com/xo/dburl"
"github.com/xo/usql/drivers"
"github.com/xo/usql/env"
"github.com/xo/usql/metacmd"
"github.com/xo/usql/rline"
"github.com/xo/usql/stmt"
ustyles "github.com/xo/usql/styles"
"github.com/xo/usql/text"
)
// Handler is a input process handler.
type Handler struct {
l rline.IO
user *user.User
wd string
nopw bool
// slm is single line mode
slm bool
// query statement buffer
buf *stmt.Stmt
lastPrefix string
last string
// connection
u *dburl.URL
db *sql.DB
tx *sql.Tx
}
// New creates a new input handler.
func New(l rline.IO, user *user.User, wd string, nopw bool) *Handler {
// set help intercept
f, iactive := l.Next, l.Interactive()
if iactive {
f = func() ([]rune, error) {
// next line
r, err := l.Next()
if err != nil {
return nil, err
}
// check if line starts with help
rlen := len(r)
if rlen >= 4 && stmt.StartsWith(r, 0, rlen, text.HelpPrefix) {
fmt.Fprintln(l.Stdout(), text.HelpDesc)
return nil, nil
}
// save history
l.Save(string(r))
return r, nil
}
}
h := &Handler{
l: l,
user: user,
wd: wd,
nopw: nopw,
buf: stmt.New(f),
}
if iactive {
l.SetOutput(h.outputHighlighter)
}
return h
}
// outputHighlighter returns s as a highlighted string, based on the current
// buffer and syntax highlighting settings.
func (h *Handler) outputHighlighter(s string) string {
// bail when string is empty (ie, contains no printable, non-space
// characters) or if syntax highlighting is not enabled
if empty(s) || env.All()["SYNTAX_HL"] != "true" {
return s
}
// count end lines
var endl string
for strings.HasSuffix(s, lineterm) {
s = strings.TrimSuffix(s, lineterm)
endl += lineterm
}
// capture current query statement buffer
orig := h.buf.String()
full := orig
if full != "" {
full += "\n"
}
full += s
// setup statement parser
st := stmt.New(func() func() ([]rune, error) {
y := strings.Split(orig, "\n")
if y[0] == "" {
y[0] = s
} else {
y = append(y, s)
}
return func() ([]rune, error) {
if len(y) > 0 {
z := y[0]
y = y[1:]
return []rune(z), nil
}
return nil, io.EOF
}
}())
drivers.ConfigStmt(h.u, st)
// accumulate all "active" statements in buffer, breaking either at
// EOF or when a \ cmd has been encountered
var err error
var cmd, final string
for {
cmd, _, err = st.Next()
if err != nil && err != io.EOF {
return s + endl
} else if err == io.EOF {
break
}
if st.Ready() || cmd != "" {
final += st.String()
st.Reset(nil)
// grab remaining whitespace to add to final
l := len(final)
if i := strings.IndexFunc(full[l:], func(r rune) bool { return !unicode.IsSpace(r) }); i != -1 {
final += full[l : l+i]
}
}
}
if !st.Ready() && cmd == "" {
final += st.String()
}
// determine whatever is remaining after "active"
var remaining string
if len(final) < len(full) {
remaining = full[len(final):]
}
// this happens when a read line is empty and/or has only
// whitespace and a \ cmd
if s == remaining {
return s + endl
}
// highlight entire final accumulated buffer
b := new(bytes.Buffer)
if err := h.Highlight(b, final); err != nil {
return s + endl
}
colored := b.String()
// return only last line plus whatever remaining string (ie, after
// a \ cmd) and the end line count
ss := strings.Split(colored, "\n")
return lastcolor(colored) + ss[len(ss)-1] + remaining + endl
}
// Run executes queries and commands.
func (h *Handler) Run() error {
stdout, stderr, iactive := h.l.Stdout(), h.l.Stderr(), h.l.Interactive()
// display welcome info
if iactive {
fmt.Fprintln(h.l.Stdout(), text.WelcomeDesc)
fmt.Fprintln(h.l.Stdout())
}
for {
var err error
var execute bool
// set prompt
if iactive {
h.l.Prompt(h.Prompt())
}
// read next statement/command
cmd, params, err := h.buf.Next()
switch {
case h.slm && err == nil:
execute = h.buf.Len != 0
case err == rline.ErrInterrupt:
h.buf.Reset(nil)
continue
case err != nil:
return err
}
var res metacmd.Res
if cmd != "" {
cmd = strings.TrimPrefix(cmd, `\`)
// decode
var r metacmd.Runner
r, err = metacmd.Decode(cmd, params)
switch {
case err == text.ErrUnknownCommand:
fmt.Fprintf(stderr, text.InvalidCommand, cmd)
fmt.Fprintln(stderr)
continue
case err == text.ErrMissingRequiredArgument:
fmt.Fprintf(stderr, text.MissingRequiredArg, cmd)
fmt.Fprintln(stderr)
continue
case err != nil:
fmt.Fprintf(stderr, "error: %v", err)
fmt.Fprintln(stderr)
continue
}
// run
res, err = r.Run(h)
if err != nil && err != rline.ErrInterrupt {
fmt.Fprintf(stderr, "error: %v", err)
fmt.Fprintln(stderr)
continue
}
// print unused command parameters
for i := res.Processed; i < len(params); i++ {
fmt.Fprintf(stdout, text.ExtraArgumentIgnored, cmd, params[i])
fmt.Fprintln(stdout)
}
}
// quit
if res.Quit {
return nil
}
// execute buf
if execute || h.buf.Ready() || res.Exec != metacmd.ExecNone {
if h.buf.Len != 0 {
h.lastPrefix, h.last = h.buf.Prefix, h.buf.String()
h.buf.Reset(nil)
}
// log.Printf(">> PROCESS EXECUTE: (%s) `%s`", h.lastPrefix, h.last)
if h.last != "" && h.last != ";" {
err = h.Execute(stdout, res, h.lastPrefix, h.last)
if err != nil {
fmt.Fprintf(stderr, "error: %v", err)
fmt.Fprintln(stderr)
}
}
}
}
}
// Execute executes a query against the connected database.
func (h *Handler) Execute(w io.Writer, res metacmd.Res, prefix, qstr string) error {
if h.db == nil {
return text.ErrNotConnected
}
// determine type and pre process string
prefix, qstr, qtyp, err := drivers.Process(h.u, prefix, qstr)
if err != nil {
return drivers.WrapErr(h.u.Driver, err)
}
f := h.execOnly
switch res.Exec {
case metacmd.ExecSet:
f = h.execSet
case metacmd.ExecExec:
f = h.execExec
}
return drivers.WrapErr(h.u.Driver, f(w, prefix, qstr, qtyp, res.ExecParam))
}
// CommandRunner executes a set of commands.
func (h *Handler) CommandRunner(cmds []string) func() error {
h.slm = true
return func() error {
for _, cmd := range cmds {
h.Reset([]rune(cmd))
err := h.Run()
if err != nil && err != io.EOF {
return err
}
}
return nil
}
}
// Reset resets the handler's query statement buffer.
func (h *Handler) Reset(r []rune) {
h.buf.Reset(r)
h.last, h.lastPrefix = "", ""
}
// Prompt creates the prompt text.
func (h *Handler) Prompt() string {
s := text.NotConnected
if h.db != nil {
s = h.u.Short()
if s == "" {
s = "(" + h.u.Driver + ")"
}
}
tx := ">"
if h.tx != nil {
tx = "~"
}
return s + h.buf.State() + tx + " "
}
// IO returns the io for the handler.
func (h *Handler) IO() rline.IO {
return h.l
}
// User returns the user for the handler.
func (h *Handler) User() *user.User {
return h.user
}
// URL returns the URL for the handler.
func (h *Handler) URL() *dburl.URL {
return h.u
}
// DB returns the sql.DB for the handler.
func (h *Handler) DB() drivers.DB {
if h.tx != nil {
return h.tx
}
return h.db
}
// Last returns the last executed statement.
func (h *Handler) Last() string {
return h.last
}
// Buf returns the current query statement buffer.
func (h *Handler) Buf() *stmt.Stmt {
return h.buf
}
// Highlight highlights using the current environment settings.
func (h *Handler) Highlight(w io.Writer, buf string) error {
vars := env.All()
// create lexer, formatter, styler
l := chroma.Coalesce(drivers.Lexer(h.u))
f := formatters.Get(vars["SYNTAX_HL_FORMAT"])
s := styles.Get(vars["SYNTAX_HL_STYLE"])
// override background
if vars["SYNTAX_HL_OVERRIDE_BG"] != "false" {
s = ustyles.Get(vars["SYNTAX_HL_STYLE"])
}
// tokenize stream
it, err := l.Tokenise(nil, buf)
if err != nil {
return err
}
// write formatted output
return f.Format(w, s, it)
}
// Open handles opening a specified database URL, passing either a single
// string in the form of a URL, or more than one string, in which case the
// first string is treated as a driver name, and the remaining strings are
// joined (with a space) and passed as a DSN to sql.Open.
//
// If there is only one parameter, and it is not a well formatted URL, but
// appears to be a file on disk, then an attempt will be made to open it with
// an appropriate driver (mysql, postgres, sqlite3) depending on the type (unix
// domain socket, directory, or regular file, respectively).
func (h *Handler) Open(params ...string) error {
if len(params) == 0 || params[0] == "" {
return nil
}
if h.tx != nil {
return text.ErrPreviousTransactionExists
}
var err error
if len(params) < 2 {
urlstr := params[0]
// parse dsn
h.u, err = dburl.Parse(urlstr)
switch {
case err == dburl.ErrInvalidDatabaseScheme:
var fi os.FileInfo
fi, err = os.Stat(urlstr)
if err != nil {
return err
}
switch {
case fi.IsDir():
return h.Open("postgres+unix:" + urlstr)
case fi.Mode()&os.ModeSocket != 0:
return h.Open("mysql+unix:" + urlstr)
}
// it is a file, so reattempt to open it with sqlite3
return h.Open("sqlite3:" + urlstr)
case err != nil:
return err
}
// force parameters
h.forceParams(h.u)
} else {
h.u = &dburl.URL{
Driver: params[0],
DSN: strings.Join(params[1:], " "),
}
}
// open connection
h.db, err = drivers.Open(h.u)
if err != nil && !drivers.IsPasswordErr(h.u, err) {
defer h.Close()
return err
} else if err == nil {
// force error/check connection
err = drivers.Ping(h.u, h.db)
if err == nil {
return h.Version()
}
}
// set buffer options
drivers.ConfigStmt(h.u, h.buf)
// bail without getting password
if h.nopw || !drivers.IsPasswordErr(h.u, err) || len(params) > 1 || !h.l.Interactive() {
defer h.Close()
return err
}
// print the error
fmt.Fprintf(h.l.Stderr(), "error: %v", err)
fmt.Fprintln(h.l.Stderr())
// otherwise, try to collect a password ...
dsn, err := h.Password(params[0])
if err != nil {
// close connection
defer h.Close()
return err
}
// reconnect
return h.Open(dsn)
}
// forceParams forces connection parameters on a database URL, adding any
// driver specific required parameters, and the username/password when a
// matching entry exists in the PASS file.
func (h *Handler) forceParams(u *dburl.URL) {
// force driver parameters
drivers.ForceParams(u)
// see if password entry is present
user, err := env.PassFileEntry(h.user, u)
if err != nil {
errout := h.l.Stderr()
fmt.Fprintf(errout, "error: %v", err)
fmt.Fprintln(errout)
} else if user != nil {
u.User = user
}
// copy back to u
z, _ := dburl.Parse(u.String())
*u = *z
}
// Password collects a password from input, and returns a modified DSN
// including the collected password.
func (h *Handler) Password(dsn string) (string, error) {
var err error
if dsn == "" {
return "", text.ErrMissingDSN
}
u, err := dburl.Parse(dsn)
if err != nil {
return "", err
}
user := h.user.Username
if u.User != nil {
user = u.User.Username()
}
pass, err := h.l.Password(text.EnterPassword)
if err != nil {
return "", err
}
u.User = url.UserPassword(user, pass)
return u.String(), nil
}
// Close closes the database connection if it is open.
func (h *Handler) Close() error {
if h.tx != nil {
return text.ErrPreviousTransactionExists
}
if h.db != nil {
err := h.db.Close()
drv := h.u.Driver
h.db, h.u = nil, nil
return drivers.WrapErr(drv, err)
}
return nil
}
// ReadVar reads a variable from the interactive prompt, saving it to
// environment variables.
func (h *Handler) ReadVar(typ, prompt string) (string, error) {
if !h.l.Interactive() {
return "", text.ErrNotInteractive
}
var masked bool
// check type
switch typ {
case "password":
masked = true
case "string", "int", "uint", "float", "bool":
default:
return "", text.ErrInvalidType
}
var v string
var err error
if masked {
if prompt == "" {
prompt = text.EnterPassword
}
v, err = h.l.Password(prompt)
} else {
h.l.Prompt(prompt)
var r []rune
r, err = h.l.Next()
v = string(r)
}
var z interface{} = v
switch typ {
case "int":
z, err = strconv.ParseInt(v, 10, 64)
case "uint":
z, err = strconv.ParseUint(v, 10, 64)
case "float":
z, err = strconv.ParseFloat(v, 64)
case "bool":
z, err = strconv.ParseBool(v)
}
if err != nil {
return "", text.ErrInvalidValue
}
return fmt.Sprintf("%v", z), nil
}
// ChangePassword changes a password for the user.
func (h *Handler) ChangePassword(user string) (string, error) {
if h.db == nil {
return "", text.ErrNotConnected
}
if !h.l.Interactive() {
return "", text.ErrNotInteractive
}
var err error
err = drivers.CanChangePassword(h.u)
if err != nil {
return "", err
}
var newpw, newpw2, oldpw string
// ask for previous password
if user == "" && drivers.RequirePreviousPassword(h.u) {
oldpw, err = h.l.Password(text.EnterPreviousPassword)
if err != nil {
return "", err
}
}
// attempt to get passwords
for i := 0; i < 3; i++ {
newpw, err = h.l.Password(text.NewPassword)
if err != nil {
return "", err
}
newpw2, err = h.l.Password(text.ConfirmPassword)
if err != nil {
return "", err
}
if newpw == newpw2 {
break
}
fmt.Fprintln(h.l.Stderr(), text.PasswordsDoNotMatch)
}
if newpw != newpw2 {
return "", text.ErrPasswordAttemptsExhausted
}
return drivers.ChangePassword(h.u, h.DB(), user, newpw, oldpw)
}
// Version prints the database version information after a successful connection.
func (h *Handler) Version() error {
if env.All()["SHOW_HOST_INFORMATION"] != "true" {
return nil
}
if h.db == nil {
return text.ErrNotConnected
}
ver, err := drivers.Version(h.u, h.DB())
if err != nil {
ver = fmt.Sprintf("<unknown, error: %v>", err)
}
if ver != "" {
out := h.l.Stdout()
fmt.Fprintf(out, text.ConnInfo, h.u.Driver, ver)
fmt.Fprintln(out)
}
return nil
}
// timefmt returns the current time format setting.
func (h *Handler) timefmt() string {
s, ok := env.All()["TIME_FORMAT"]
if !ok || s == "" {
s = time.RFC3339Nano
}
return s
}
// execOnly executes a query against the database.
func (h *Handler) execOnly(w io.Writer, prefix, qstr string, qtyp bool, _ string) error {
// exec or query
f := h.exec
if qtyp {
f = h.query
}
// exec
return f(w, prefix, qstr)
}
// execSet executes a SQL query, setting all returned columns as variables.
func (h *Handler) execSet(w io.Writer, prefix, qstr string, _ bool, namePrefix string) error {
// query
q, err := h.DB().Query(qstr)
if err != nil {
return err
}
// get cols
cols, err := drivers.Columns(h.u, q)
if err != nil {
return err
}
// process row(s)
var i int
var row []string
clen, tfmt := len(cols), h.timefmt()
for q.Next() {
if i == 0 {
row, err = h.scan(q, clen, tfmt)
if err != nil {
return err
}
}
i++
}
if i > 1 {
return text.ErrTooManyRows
}
// set vars
for i, c := range cols {
n := namePrefix + c
if err = env.ValidIdentifier(n); err != nil {
return fmt.Errorf(text.CouldNotSetVariable, n)
}
env.Set(n, row[i])
}
return nil
}
// execExec executes a query and re-executes all columns of all rows as if they
// were their own queries.
func (h *Handler) execExec(w io.Writer, prefix, qstr string, qtyp bool, _ string) error {
// query
q, err := h.DB().Query(qstr)
if err != nil {
return err
}
// execRows
err = h.execRows(w, q)
if err != nil {
return err
}
// check for additional result sets ...
for drivers.NextResultSet(q) {
err = h.execRows(w, q)
if err != nil {
return err
}
}
return nil
}
// query executes a query against the database.
func (h *Handler) query(w io.Writer, _, qstr string) error {
var err error
// run query
q, err := h.DB().Query(qstr)
if err != nil {
return err
}
defer q.Close()
// output rows
err = h.outputRows(w, q)
if err != nil {
return err
}
// check for additional result sets ...
for drivers.NextResultSet(q) {
err = h.outputRows(w, q)
if err != nil {
return err
}
}
return nil
}
// execRows executes all the columns in the row.
func (h *Handler) execRows(w io.Writer, q *sql.Rows) error {
var err error
// get columns
cols, err := drivers.Columns(h.u, q)
if err != nil {
return err
}
// process rows
res := metacmd.Res{Exec: metacmd.ExecOnly}
clen, tfmt := len(cols), h.timefmt()
for q.Next() {
if clen != 0 {
row, err := h.scan(q, clen, tfmt)
if err != nil {
return err
}
// execute
for _, qstr := range row {
err = h.Execute(w, res, stmt.FindPrefix(qstr, 4), qstr)
if err != nil {
return err
}
}
}
}
return nil
}
// outputRows outputs the supplied SQL rows to the supplied writer.
func (h *Handler) outputRows(w io.Writer, q *sql.Rows) error {
// get columns
cols, err := drivers.Columns(h.u, q)
if err != nil {
return err
}
// create output table
t := tablewriter.NewWriter(w)
t.SetAutoFormatHeaders(false)
t.SetBorder(false)
t.SetAutoWrapText(false)
t.SetHeader(cols)
// process rows
var rows int
clen, tfmt := len(cols), h.timefmt()
for q.Next() {
if clen != 0 {
row, err := h.scan(q, clen, tfmt)
if err != nil {
return err
}
t.Append(row)
rows++
}
}
t.Render()
// row count
fmt.Fprintf(w, text.RowCount, rows)
fmt.Fprintln(w)
fmt.Fprintln(w)
return nil
}
// scan scans a row.
func (h *Handler) scan(q *sql.Rows, clen int, tfmt string) ([]string, error) {
r := make([]interface{}, clen)
for i := range r {
r[i] = new(interface{})
}
err := q.Scan(r...)
if err != nil {
return nil, err
}
row := make([]string, clen)
for n, z := range r {
j := z.(*interface{})
//log.Printf(">>> %s: %s", cols[n], reflect.TypeOf(*j))
switch x := (*j).(type) {
case []byte:
row[n] = drivers.ConvertBytes(h.u, tfmt, x)
case string:
row[n] = x
case time.Time:
row[n] = x.Format(tfmt)
case fmt.Stringer:
row[n] = x.String()
default:
row[n] = fmt.Sprintf("%v", *j)
}
}
return row, err
}
// exec does a database exec.
func (h *Handler) exec(w io.Writer, typ, qstr string) error {
var err error
res, err := h.DB().Exec(qstr)
if err != nil {
return err
}
// get affected
count, err := drivers.RowsAffected(h.u, res)
if err != nil {
return err
}
// print name
fmt.Fprint(w, typ)
// print count
if count > 0 {
fmt.Fprint(w, " ", count)
}
fmt.Fprintln(w)
return nil
}
// Begin begins a transaction.
func (h *Handler) Begin() error {
if h.db == nil {
return text.ErrNotConnected
}
if h.tx != nil {
return text.ErrPreviousTransactionExists
}
var err error
h.tx, err = h.db.Begin()
if err != nil {
return drivers.WrapErr(h.u.Driver, err)
}
return nil
}
// Commit commits a transaction.
func (h *Handler) Commit() error {
if h.db == nil {
return text.ErrNotConnected
}
if h.tx == nil {
return text.ErrNoPreviousTransactionExists
}
tx := h.tx
h.tx = nil
err := tx.Commit()
if err != nil {
return drivers.WrapErr(h.u.Driver, err)
}
return nil
}
// Rollback rollbacks a transaction.
func (h *Handler) Rollback() error {
if h.db == nil {
return text.ErrNotConnected
}
if h.tx == nil {
return text.ErrNoPreviousTransactionExists
}
tx := h.tx
h.tx = nil
err := tx.Rollback()
if err != nil {
return drivers.WrapErr(h.u.Driver, err)
}