From f37e55d9f1204dcca5015fac3ded8d0e7493ce89 Mon Sep 17 00:00:00 2001
From: dudaodong <dudaodong@gmail.com>
Date: Sun, 24 Sep 2023 19:19:09 +0800
Subject: [PATCH] feat: add ReadFile

---
 docs/fileutil.md       | 39 +++++++++++++++++++++++++++++++++++++++
 docs/fileutil_zh-CN.md | 39 +++++++++++++++++++++++++++++++++++++++
 fileutil/file.go       | 25 +++++++++++++++++++++++--
 fileutil/file_test.go  | 23 +++++++++++++++++++++++
 4 files changed, 124 insertions(+), 2 deletions(-)

diff --git a/docs/fileutil.md b/docs/fileutil.md
index 3e04b44..7923dc7 100644
--- a/docs/fileutil.md
+++ b/docs/fileutil.md
@@ -47,6 +47,7 @@ import (
 -   [WriteCsvFile](#WriteCsvFile)
 -   [WriteStringToFile](#WriteStringToFile)
 -   [WriteBytesToFile](#WriteBytesToFile)
+-   [ReadFile](#ReadFile)
 
 <div STYLE="page-break-after: always;"></div>
 
@@ -827,3 +828,41 @@ func main() {
     // hello
 }
 ```
+
+### <span id="ReadFile">ReadFile</span>
+
+<p>Read File/URL</p>
+
+<b>Signature:</b>
+
+```go
+func ReadFile(path string) (reader io.ReadCloser, closeFn func(), err error) 
+```
+
+<b>Example:<span style="float:right;display:inline-block;"> </span></b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/fileutil"
+)
+
+func main() {
+   reader, fn, err := ReadFile("https://httpbin.org/robots.txt")
+    if err != nil {
+        return
+    }
+    defer fn()
+
+    dat, err := io.ReadAll(reader)
+    if err != nil {
+        return
+    }
+    fmt.Println(string(dat))
+    // Output:
+    // User-agent: *
+    // Disallow: /deny
+}
+```
\ No newline at end of file
diff --git a/docs/fileutil_zh-CN.md b/docs/fileutil_zh-CN.md
index c3340f7..1264341 100644
--- a/docs/fileutil_zh-CN.md
+++ b/docs/fileutil_zh-CN.md
@@ -47,6 +47,7 @@ import (
 -   [WriteCsvFile](#WriteCsvFile)
 -   [WriteStringToFile](#WriteStringToFile)
 -   [WriteBytesToFile](#WriteBytesToFile)
+-   [ReadFile](#ReadFile)
 
 <div STYLE="page-break-after: always;"></div>
 
@@ -827,3 +828,41 @@ func main() {
     // hello
 }
 ```
+
+### <span id="ReadFile">ReadFile</span>
+
+<p>读取文件或者URL</p>
+
+<b>函数签名:</b>
+
+```go
+func ReadFile(path string) (reader io.ReadCloser, closeFn func(), err error)
+```
+
+<b>示例:<span style="float:right;display:inline-block;"></span></b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/fileutil"
+)
+
+func main() {
+   reader, fn, err := ReadFile("https://httpbin.org/robots.txt")
+    if err != nil {
+        return
+    }
+    defer fn()
+
+    dat, err := io.ReadAll(reader)
+    if err != nil {
+        return
+    }
+    fmt.Println(string(dat))
+    // Output:
+    // User-agent: *
+    // Disallow: /deny
+}
+```
diff --git a/fileutil/file.go b/fileutil/file.go
index cdceb10..c0ee82c 100644
--- a/fileutil/file.go
+++ b/fileutil/file.go
@@ -19,10 +19,11 @@ import (
 	"io/ioutil"
 	"net/http"
 	"os"
-	"path"
 	"path/filepath"
 	"runtime"
 	"strings"
+
+	"github.com/duke-git/lancet/validator"
 )
 
 // IsExist checks if a file or directory exists
@@ -449,7 +450,7 @@ func CurrentPath() string {
 	var absPath string
 	_, filename, _, ok := runtime.Caller(1)
 	if ok {
-		absPath = path.Dir(filename)
+		absPath = filepath.Dir(filename)
 	}
 
 	return absPath
@@ -589,3 +590,23 @@ func WriteBytesToFile(filepath string, content []byte) error {
 	_, err = f.Write(content)
 	return err
 }
+
+// ReadFile get file reader by a url or a local file.
+func ReadFile(path string) (reader io.ReadCloser, closeFn func(), err error) {
+	switch {
+	case validator.IsUrl(path):
+		resp, err := http.Get(path)
+		if err != nil {
+			return nil, func() {}, err
+		}
+		return resp.Body, func() { resp.Body.Close() }, nil
+	case IsExist(path):
+		reader, err := os.Open(path)
+		if err != nil {
+			return nil, func() {}, err
+		}
+		return reader, func() { reader.Close() }, nil
+	default:
+		return nil, func() {}, errors.New("unknown file type")
+	}
+}
diff --git a/fileutil/file_test.go b/fileutil/file_test.go
index f9f05b6..1572a3c 100644
--- a/fileutil/file_test.go
+++ b/fileutil/file_test.go
@@ -1,6 +1,7 @@
 package fileutil
 
 import (
+	"io"
 	"os"
 	"testing"
 
@@ -294,7 +295,11 @@ func TestSha(t *testing.T) {
 	assert := internal.NewAssert(t, "TestSha")
 
 	sha1, err := Sha("./testdata/test.txt", 1)
+	assert.IsNil(err)
+
 	sha256, err := Sha("./testdata/test.txt", 256)
+	assert.IsNil(err)
+
 	sha512, err := Sha("./testdata/test.txt", 512)
 
 	assert.IsNil(err)
@@ -401,3 +406,21 @@ func TestWriteBytesToFile(t *testing.T) {
 
 	os.Remove(filepath)
 }
+
+func TestReadFile(t *testing.T) {
+	reader, close, err := ReadFile("https://httpbin.org/robots.txt")
+	if err != nil {
+		t.Fail()
+	}
+	defer close()
+
+	dat, err := io.ReadAll(reader)
+	if err != nil {
+		t.Fail()
+	}
+
+	want := `User-agent: *
+Disallow: /deny
+`
+	internal.NewAssert(t, "TestReadFile").Equal(want, string(dat))
+}