VictoriaMetrics/app/vlogscli/main.go
2024-10-07 14:46:21 +02:00

358 lines
8.8 KiB
Go

package main
import (
"context"
"errors"
"flag"
"fmt"
"io"
"io/fs"
"net/http"
"net/url"
"os"
"os/signal"
"strconv"
"strings"
"syscall"
"time"
"github.com/ergochat/readline"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/buildinfo"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/envflag"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/flagutil"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/logstorage"
)
var (
datasourceURL = flag.String("datasource.url", "http://localhost:9428/select/logsql/query", "URL for querying VictoriaLogs; "+
"see https://docs.victoriametrics.com/victorialogs/querying/#querying-logs")
historyFile = flag.String("historyFile", "vlogscli-history", "Path to file with command history")
header = flagutil.NewArrayString("header", "Optional header to pass in request -datasource.url in the form 'HeaderName: value'")
)
const (
firstLinePrompt = ";> "
nextLinePrompt = ""
)
func main() {
// Write flags and help message to stdout, since it is easier to grep or pipe.
flag.CommandLine.SetOutput(os.Stdout)
flag.Usage = usage
envflag.Parse()
buildinfo.Init()
logger.InitNoLogFlags()
hes, err := parseHeaders(*header)
if err != nil {
fatalf("cannot parse -header command-line flag: %s", err)
}
headers = hes
incompleteLine := ""
cfg := &readline.Config{
Prompt: firstLinePrompt,
DisableAutoSaveHistory: true,
Listener: func(line []rune, pos int, _ rune) ([]rune, int, bool) {
incompleteLine = string(line)
return line, pos, false
},
}
rl, err := readline.NewFromConfig(cfg)
if err != nil {
fatalf("cannot initialize readline: %s", err)
}
fmt.Fprintf(rl, "sending queries to %s\n", *datasourceURL)
runReadlineLoop(rl, &incompleteLine)
if err := rl.Close(); err != nil {
fatalf("cannot close readline: %s", err)
}
}
func runReadlineLoop(rl *readline.Instance, incompleteLine *string) {
historyLines, err := loadFromHistory(*historyFile)
if err != nil {
fatalf("cannot load query history: %s", err)
}
for _, line := range historyLines {
if err := rl.SaveToHistory(line); err != nil {
fatalf("cannot initialize query history: %s", err)
}
}
outputMode := outputModeJSONMultiline
s := ""
for {
line, err := rl.ReadLine()
if err != nil {
switch err {
case io.EOF:
if s != "" {
// This is non-interactive query execution.
if err := executeQuery(context.Background(), rl, s, outputMode); err != nil {
fmt.Fprintf(rl, "%s\n", err)
}
}
return
case readline.ErrInterrupt:
if s == "" && *incompleteLine == "" {
fmt.Fprintf(rl, "interrupted\n")
os.Exit(128 + int(syscall.SIGINT))
}
// Default value for Ctrl+C - clear the prompt and store the incompletely entered line into history
s += *incompleteLine
historyLines = pushToHistory(rl, historyLines, s)
s = ""
rl.SetPrompt(firstLinePrompt)
continue
default:
fatalf("unexpected error in readline: %s", err)
}
}
s += line
if s == "" {
// Skip empty lines
continue
}
if isQuitCommand(s) {
fmt.Fprintf(rl, "bye!\n")
_ = pushToHistory(rl, historyLines, s)
return
}
if isHelpCommand(s) {
printCommandsHelp(rl)
historyLines = pushToHistory(rl, historyLines, s)
s = ""
continue
}
if s == `\s` {
fmt.Fprintf(rl, "singleline json output mode\n")
outputMode = outputModeJSONSingleline
historyLines = pushToHistory(rl, historyLines, s)
s = ""
continue
}
if s == `\m` {
fmt.Fprintf(rl, "multiline json output mode\n")
outputMode = outputModeJSONMultiline
historyLines = pushToHistory(rl, historyLines, s)
s = ""
continue
}
if s == `\logfmt` {
fmt.Fprintf(rl, "logfmt output mode\n")
outputMode = outputModeLogfmt
historyLines = pushToHistory(rl, historyLines, s)
s = ""
continue
}
if line != "" && !strings.HasSuffix(line, ";") {
// Assume the query is incomplete and allow the user finishing the query on the next line
s += "\n"
rl.SetPrompt(nextLinePrompt)
continue
}
// Execute the query
ctx, cancel := signal.NotifyContext(context.Background(), os.Interrupt)
err = executeQuery(ctx, rl, s, outputMode)
cancel()
if err != nil {
if errors.Is(err, context.Canceled) {
fmt.Fprintf(rl, "\n")
} else {
fmt.Fprintf(rl, "%s\n", err)
}
// Save queries in the history even if they weren't finished successfully
}
historyLines = pushToHistory(rl, historyLines, s)
s = ""
rl.SetPrompt(firstLinePrompt)
}
}
func pushToHistory(rl *readline.Instance, historyLines []string, s string) []string {
s = strings.TrimSpace(s)
if len(historyLines) == 0 || historyLines[len(historyLines)-1] != s {
historyLines = append(historyLines, s)
if len(historyLines) > 500 {
historyLines = historyLines[len(historyLines)-500:]
}
if err := saveToHistory(*historyFile, historyLines); err != nil {
fatalf("cannot save query history: %s", err)
}
}
if err := rl.SaveToHistory(s); err != nil {
fatalf("cannot update query history: %s", err)
}
return historyLines
}
func loadFromHistory(filePath string) ([]string, error) {
data, err := os.ReadFile(filePath)
if err != nil {
if errors.Is(err, fs.ErrNotExist) {
return nil, nil
}
return nil, err
}
linesQuoted := strings.Split(string(data), "\n")
lines := make([]string, 0, len(linesQuoted))
i := 0
for _, lineQuoted := range linesQuoted {
i++
if lineQuoted == "" {
continue
}
line, err := strconv.Unquote(lineQuoted)
if err != nil {
return nil, fmt.Errorf("cannot parse line #%d at %s: %w; line: [%s]", i, filePath, err, line)
}
lines = append(lines, line)
}
return lines, nil
}
func saveToHistory(filePath string, lines []string) error {
linesQuoted := make([]string, len(lines))
for i, line := range lines {
lineQuoted := strconv.Quote(line)
linesQuoted[i] = lineQuoted
}
data := strings.Join(linesQuoted, "\n")
return os.WriteFile(filePath, []byte(data), 0600)
}
func isQuitCommand(s string) bool {
switch s {
case `\q`, "q", "quit", "exit":
return true
default:
return false
}
}
func isHelpCommand(s string) bool {
switch s {
case `\h`, "h", "help", "?":
return true
default:
return false
}
}
func printCommandsHelp(w io.Writer) {
fmt.Fprintf(w, "%s", `List of available commands:
\q - quit
\h - show this help
\s - singleline json output mode
\m - multiline json output mode
\logfmt - logfmt output mode
`)
}
func executeQuery(ctx context.Context, output io.Writer, s string, outputMode outputMode) error {
// Parse the query and convert it to canonical view.
s = strings.TrimSuffix(s, ";")
q, err := logstorage.ParseQuery(s)
if err != nil {
return fmt.Errorf("cannot parse query: %w", err)
}
qStr := q.String()
fmt.Fprintf(output, "executing [%s]...", qStr)
// Prepare HTTP request for VictoriaLogs
args := make(url.Values)
args.Set("query", qStr)
data := strings.NewReader(args.Encode())
req, err := http.NewRequestWithContext(ctx, "POST", *datasourceURL, data)
if err != nil {
panic(fmt.Errorf("BUG: cannot prepare request to server: %w", err))
}
req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
for _, h := range headers {
req.Header.Set(h.Name, h.Value)
}
// Execute HTTP request at VictoriaLogs
startTime := time.Now()
resp, err := httpClient.Do(req)
queryDuration := time.Since(startTime)
fmt.Fprintf(output, "; duration: %.3fs\n", queryDuration.Seconds())
if err != nil {
return fmt.Errorf("cannot execute query: %w", err)
}
defer func() {
_ = resp.Body.Close()
}()
if resp.StatusCode != http.StatusOK {
body, err := io.ReadAll(resp.Body)
if err != nil {
body = []byte(fmt.Sprintf("cannot read response body: %s", err))
}
return fmt.Errorf("unexpected status code: %d; response body:\n%s", resp.StatusCode, body)
}
// Prettify the response and stream it to 'less'.
jp := newJSONPrettifier(resp.Body, outputMode)
defer func() {
_ = jp.Close()
}()
if err := readWithLess(jp); err != nil {
return fmt.Errorf("error when reading query response: %w", err)
}
return nil
}
var httpClient = &http.Client{}
var headers []headerEntry
type headerEntry struct {
Name string
Value string
}
func parseHeaders(a []string) ([]headerEntry, error) {
hes := make([]headerEntry, len(a))
for i, s := range a {
a := strings.SplitN(s, ":", 2)
if len(a) != 2 {
return nil, fmt.Errorf("cannot parse header=%q; it must contain at least one ':'; for example, 'Cookie: foo'", s)
}
hes[i] = headerEntry{
Name: strings.TrimSpace(a[0]),
Value: strings.TrimSpace(a[1]),
}
}
return hes, nil
}
func fatalf(format string, args ...any) {
fmt.Fprintf(os.Stderr, format+"\n", args...)
os.Exit(1)
}
func usage() {
const s = `
vlogscli is a command-line tool for querying VictoriaLogs.
See the docs at https://docs.victoriametrics.com/victorialogs/querying/vlogscli/
`
flagutil.Usage(s)
}