feat: use dbfs to store log

modules/bots/log.go

@@ -0,0 +1,130 @@
+// Copyright 2022 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package bots
+
+import (
+	"bufio"
+	"context"
+	"fmt"
+	"io"
+	"net/url"
+	"os"
+	"strconv"
+	"strings"
+	"time"
+
+	"code.gitea.io/gitea/models/dbfs"
+	runnerv1 "gitea.com/gitea/proto-go/runner/v1"
+
+	"google.golang.org/protobuf/types/known/timestamppb"
+)
+
+const defaultBufSize = 64 * 1024
+
+const (
+	StorageSchemaDBFS = "dbfs"
+	StorageSchemaS2   = "s2"
+	// ...
+)
+
+func WriteLogs(ctx context.Context, rawURL string, offset int64, rows []*runnerv1.LogRow) ([]int, error) {
+	name, err := parseDBFSName(rawURL)
+	if err != nil {
+		return nil, err
+	}
+	f, err := dbfs.OpenFile(ctx, name, os.O_RDWR|os.O_CREATE|os.O_TRUNC|os.O_APPEND)
+	if err != nil {
+		return nil, fmt.Errorf("dbfs OpenFile %q: %w", name, err)
+	}
+	defer f.Close()
+	if _, err := f.Seek(offset, io.SeekStart); err != nil {
+		return nil, fmt.Errorf("dbfs Seek %q: %w", name, err)
+	}
+
+	writer := bufio.NewWriterSize(f, defaultBufSize)
+
+	ns := make([]int, 0, len(rows))
+	for _, row := range rows {
+		n, err := writer.WriteString(FormatLog(row.Time.AsTime(), row.Content) + "\n")
+		if err != nil {
+			return nil, err
+		}
+		ns = append(ns, n)
+	}
+
+	if err := writer.Flush(); err != nil {
+		return nil, err
+	}
+	return ns, nil
+}
+
+func ReadLogs(ctx context.Context, rawURL string, offset int64, limit int64) ([]*runnerv1.LogRow, error) {
+	name, err := parseDBFSName(rawURL)
+	if err != nil {
+		return nil, err
+	}
+
+	f, err := dbfs.Open(ctx, name)
+	if err != nil {
+		return nil, fmt.Errorf("dbfs Open %q: %w", name, err)
+	}
+	defer f.Close()
+	if _, err := f.Seek(offset, io.SeekStart); err != nil {
+		return nil, fmt.Errorf("dbfs Seek %q: %w", name, err)
+	}
+
+	var rows []*runnerv1.LogRow
+	scanner := bufio.NewScanner(f)
+	for scanner.Scan() && (int64(len(rows)) < limit || limit < 0) {
+		t, c, err := ParseLog(scanner.Text())
+		if err != nil {
+			return nil, fmt.Errorf("parse log %q: %w", scanner.Text(), err)
+		}
+		rows = append(rows, &runnerv1.LogRow{
+			Time:    timestamppb.New(t),
+			Content: c,
+		})
+	}
+
+	if err := scanner.Err(); err != nil {
+		return nil, fmt.Errorf("scan: %w", err)
+	}
+
+	return rows, nil
+}
+
+func parseDBFSName(rawURL string) (string, error) {
+	u, err := url.Parse(rawURL)
+	if err != nil {
+		return "", fmt.Errorf("invalid url: %w", err)
+	}
+	if u.Scheme != StorageSchemaDBFS {
+		return "", fmt.Errorf("%s supported only yet", StorageSchemaDBFS)
+	}
+
+	if u.Path == "" {
+		return "", fmt.Errorf("empty path")
+	}
+
+	return u.Path, nil
+}
+
+func FormatLog(timestamp time.Time, content string) string {
+	return fmt.Sprintf("%s %s", timestamp.UTC().Format(time.RFC3339Nano), strconv.Quote(content))
+}
+
+func ParseLog(in string) (timestamp time.Time, content string, err error) {
+	index := strings.IndexRune(in, ' ')
+	if index < 0 {
+		err = fmt.Errorf("invalid log: %q", in)
+		return
+	}
+	timestamp, err = time.Parse(time.RFC3339Nano, in[:index])
+	if err != nil {
+		return
+	}
+	content, err = strconv.Unquote(in[index+1:])
+	return
+}