v1.0.7

v1.0.7

utils/file.go

@@ -1,13 +1,22 @@
 package utils
 
 import (
+	"bufio"
 	"errors"
 	"github.com/spf13/cast"
 	"io"
 	"os"
 	"path/filepath"
+	"sync"
 )
 
+// FileStruct - File 结构体
+type FileStruct struct {
+	request  *FileRequest
+	response *FileResponse
+}
+
+// FileRequest - File 请求
 type FileRequest struct {
 	// 文件名
 	Name string
@@ -17,27 +26,37 @@ type FileRequest struct {
 	Dir string
 	// 文件后缀
 	Ext string
+	// 限制行数
+	Limit int
+	// 读取偏移量
+	Page int
+
 }
 
-// FileStruct - File 结构体
-type FileStruct struct {
-	request  *FileRequest
-	response *FileResponse
-}
-
+// FileResponse - File 响应
 type FileResponse struct {
 	Error  error
-	Result string
+	Result any
+	Text   string
 	Byte   []byte
 	Slice  []any
 }
 
+// File - 文件系统
 func File(request ...FileRequest) *FileStruct {
 
 	if len(request) == 0 {
 		request = append(request, FileRequest{})
 	}
 
+	if IsEmpty(request[0].Limit) {
+		request[0].Limit = 10
+	}
+
+	if IsEmpty(request[0].Page) {
+		request[0].Page = 1
+	}
+
 	return &FileStruct{
 		request : &request[0],
 		response: &FileResponse{},
@@ -68,6 +87,18 @@ func (this *FileStruct) Ext(ext any) *FileStruct {
 	return this
 }
 
+// Limit 设置限制行数
+func (this *FileStruct) Limit(limit any) *FileStruct {
+	this.request.Limit = cast.ToInt(limit)
+	return this
+}
+
+// Page 设置读取偏移量
+func (this *FileStruct) Page(page any) *FileStruct {
+	this.request.Page = cast.ToInt(page)
+	return this
+}
+
 // Save 保存文件
 func (this *FileStruct) Save(reader io.Reader, path ...string) (result *FileResponse) {
 
@@ -80,9 +111,7 @@ func (this *FileStruct) Save(reader io.Reader, path ...string) (result *FileResp
 		return this.response
 	}
 
-	filePath := cast.ToString(path)
-
-	dir := filepath.Dir(filePath)
+	dir := filepath.Dir(this.request.Path)
     if _, err := os.Stat(dir); os.IsNotExist(err) {
         // 目录不存在，需要创建
         if err := os.MkdirAll(dir, 0755); err != nil {
@@ -92,7 +121,7 @@ func (this *FileStruct) Save(reader io.Reader, path ...string) (result *FileResp
     }
 
 	// 创建文件
-    file, err := os.Create(filePath)
+    file, err := os.Create(this.request.Path)
     if err != nil {
 		this.response.Error = err
 		return this.response
@@ -114,7 +143,7 @@ func (this *FileStruct) Save(reader io.Reader, path ...string) (result *FileResp
 		return this.response
 	}
 
-    return nil
+    return this.response
 }
 
 // Byte 获取文件字节
@@ -142,33 +171,51 @@ func (this *FileStruct) Byte(path ...any) (result *FileResponse) {
 		}
 	}(file)
 
-	// // 获取文件大小
-	// info, _ := file.Stat()
-	// size := info.Size()
-	// // 读取文件
-	// data := make([]byte, size)
-	// file.Read(data)
-	// return data
+	// 获取文件信息
+	info, err := file.Stat()
+	if err != nil {
+		this.response.Error = err
+		return this.response
+	}
+	size := info.Size()
 
-	var bytes []byte
-
-	// 分批次读取
-	buf := make([]byte, 1024)
-	for {
-		line, err := file.Read(buf)
+	// 小于50MB，整体读取
+	if size < 50 * 1024 * 1024 {
+		bytes := make([]byte, size)
+		_, err = file.Read(bytes)
 		if err != nil {
+			this.response.Error = err
+			return this.response
+		}
+		this.response.Byte   = bytes
+		this.response.Text   = string(bytes)
+		this.response.Result = bytes
+		return this.response
+	}
+
+	// 大于等于50MB，分块读取
+	var bytes []byte
+	buffer := make([]byte, 1024 * 1024)
+	for {
+		index, err := file.Read(buffer)
+		if err != nil && err != io.EOF {
+			this.response.Error = err
+			break
+		}
+		bytes = append(bytes, buffer[:index]...)
+		if err == io.EOF {
 			break
 		}
-		bytes = append(bytes, buf[:line]...)
 	}
 
 	this.response.Byte   = bytes
-	this.response.Result = string(bytes)
+	this.response.Text   = string(bytes)
+	this.response.Result = bytes
 
 	return this.response
 }
 
-// FileList 获取指定目录下的所有文件
+// List 获取指定目录下的所有文件
 func (this *FileStruct) List(opt ...map[string]any) (result *FileResponse) {
 
 	// 默认参数
@@ -243,5 +290,121 @@ func (this *FileStruct) List(opt ...map[string]any) (result *FileResponse) {
 	}
 
 	this.response.Slice = cast.ToSlice(slice)
+	return this.response
+}
+
+// IsExist 判断文件是否存在
+func (this *FileStruct) IsExist(path ...any) (ok bool) {
+
+	if len(path) != 0 {
+		this.request.Path = cast.ToString(path[0])
+	}
+
+	if IsEmpty(this.request.Path) {
+		return false
+	}
+
+	// 判断文件是否存在
+	if _, err := os.Stat(this.request.Path); os.IsNotExist(err) {
+		return false
+	}
+
+	return true
+}
+
+// Line 按行读取文件
+func (this *FileStruct) Line(path ...any) (result *FileResponse) {
+
+	if len(path) != 0 {
+		this.request.Path = cast.ToString(path[0])
+	}
+
+	if IsEmpty(this.request.Path) {
+		this.response.Error = errors.New("文件路径不能为空")
+		return this.response
+	}
+
+	// 读取块
+	readBlock := func(file *os.File, start int, end int) ([]string, error) {
+
+		lines   := make([]string, 0)
+		scanner := bufio.NewScanner(file)
+
+		// 移动扫描器到指定的起始行
+		for i := 1; i < start && scanner.Scan(); i++ {}
+
+		// 开始读取需要的行
+		for i := start; i <= end && scanner.Scan(); i++ {
+			// 只把需要的行保存到切片中
+			if i >= start && i <= end {
+				lines = append(lines, scanner.Text())
+			}
+		}
+
+		if err := scanner.Err(); err != nil {
+			return nil, err
+		}
+
+		return lines, nil
+	}
+
+	file, err := os.Open(this.request.Path)
+	if err != nil {
+		this.response.Error = err
+		return this.response
+	}
+	defer func(file *os.File) {
+		err := file.Close()
+		if err != nil {
+			return
+		}
+	}(file)
+
+	end   := this.request.Page * this.request.Limit
+	start := end - this.request.Limit + 1
+
+	lines     := make([]string, 0)
+	// 计算每个块的大小（以10MB为一个块）
+	blockSize := 10 * 1024 * 1024
+	numBlocks := (end - start + 1) / blockSize
+
+	if (end - start + 1) % blockSize != 0 {
+		numBlocks++
+	}
+
+	// 并发读取每个块
+	var wg sync.WaitGroup
+	wg.Add(numBlocks)
+	for i := 0; i < numBlocks; i++ {
+		go func(i int) {
+
+			startLine := start + i * blockSize
+			endLine   := startLine + blockSize - 1
+			if endLine > end {
+				endLine = end
+			}
+
+			blockLines, err := readBlock(file, startLine, endLine)
+			if err != nil {
+				this.response.Error = err
+				return
+			} else {
+				lines = append(lines, blockLines...)
+			}
+
+			wg.Done()
+		}(i)
+	}
+
+	wg.Wait()
+
+	this.response.Result = lines
+	this.response.Text   = JsonEncode(this.response.Result)
+	this.response.Byte   = []byte(this.response.Text)
+
+	for _, v := range lines {
+		this.response.Slice = append(this.response.Slice, v)
+	}
+
 	return this.response
 }