1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
|
// Package fs provides file system operations and processors for DTail server-side
// log file handling. This package implements various file processing strategies
// including tailing, reading, grepping, and MapReduce operations with efficient
// streaming and resource management.
//
// Key components:
// - FileReader interface for abstracted file operations
// - Processors for different operation types (tail, cat, grep, mapr)
// - Chunked reading for efficient large file processing
// - Permission checking with Linux ACL support (optional)
// - Statistics tracking for file operations
//
// The package supports both one-time operations (cat, grep, mapr) and continuous
// monitoring (tail) with proper resource cleanup and error handling. All processors
// implement streaming output to minimize memory usage for large files.
package fs
import (
"context"
"github.com/mimecast/dtail/internal/io/line"
"github.com/mimecast/dtail/internal/lcontext"
"github.com/mimecast/dtail/internal/regex"
)
// FileReader defines the interface for all file processing operations on the
// DTail server. This interface abstracts different file processing strategies
// (tail, cat, grep, mapr) providing a uniform way to handle various log file
// operations with context management and streaming output.
type FileReader interface {
// Start begins the file processing operation, streaming processed lines
// to the output channel. The operation respects context cancellation
// and applies regex filtering as specified.
//
// Parameters:
// ctx: Context for cancellation and timeout control
// ltx: Line context for before/after context lines and match limits
// lines: Output channel for processed log lines
// re: Compiled regex for line filtering (may be no-op for some operations)
//
// Returns:
// error: Any error encountered during file processing
Start(ctx context.Context, ltx lcontext.LContext, lines chan<- *line.Line,
re regex.Regex) error
// FilePath returns the absolute path of the file being processed.
// This is used for logging, statistics, and client identification.
FilePath() string
// Retry indicates whether this file operation should be retried
// if it fails. Typically true for tail operations (long-running)
// and false for one-time operations (cat, grep, mapr).
Retry() bool
}
|
