Filer - Utils for dealing with file uploads and validation in Golang
$ go get github.com/adelowo/filer
-
Validators : Validate files according to a set of rules
SizeValidator
Validate a file by it's size
max, _ := filer.LengthInBytes("2MB") min, _ := filer.LengthInBytes("200KB") val = NewSizeValidator(max, min) file, _ = os.Open("./path/to/file") isValid, err := val.Validate(file)
MimeTypeValidator
Validate a file by it's mimetype.
val = NewMimeTypeValidator([]string{"image/jpeg", "image/png"}) file, _ = os.Open("./path/to/file") isValid, err := val.Validate(file)
ExtensionValidator
Validate a file by it's extension.. Caveat, this is probably not what you need.
val = NewExtensionValidator([]string{"go", "php", "md", "rb", "ts"}) file, _ = os.Open("./path/to/file") isValid, err := val.Validate(file)
You can also make use of a chained validator to ease the pain of having to deal with multiple validators manually
validator := NewChainedValidator(
NewExtensionValidator([]string{"go", "ts", "jpg"}),
NewSizeValidator((1024*1024), (1024*6))) //1MB and 6 KB
file, _ := os.Open("./path/to/file.jpg")
isValid, err := validator.Validate(file)-
File Name Generators:
MD5Generator:
Get the ms5 hash sum of the file name
gen := generator.NewMD5Generator() s := gen.Generate(file) //Assuming file is `os.Open("file")`
SlugGenerator:
Generates a slugified version of the file name.
gen := generator.NewSlugGenerator() s := gen.Generate(file)
RandomGenerator:
This generates a random name for the file.. Discards the file name itself
ran := generator.NewRandomGenerator(12) //random name with a length of 12 generatedName := ran.Generate(file)
-
File Storage:
For storage, filer utilizes Afero. This is to allow making use of a single API while having multiple backends to choose from
fs = afero.NewMemMapFs() //Using an inmemory store here..
//Could be a local store,s3 store or anything.. As long as it implements `afero.Fs`
storeAdapter = storage.NewFilerStorage(fs, nil) //can also pass in a PathFunc instead of nilA sample usage of this library would be :
package main
import (
"io"
"io/ioutil"
"net/http"
"github.com/adelowo/filer/storage"
"github.com/adelowo/filer/validator"
"github.com/spf13/afero"
)
func main() {
http.HandleFunc("/upload", func(w http.ResponseWriter, r *http.Request) {
if r.Method == "GET" {
io.WriteString(w, "You came here")
return
}
if r.Method == "POST" {
file, header, err := r.FormFile("formNameInHTMLform")
if err != nil {
io.WriteString(w, err.Error())
return
}
buf, err := ioutil.ReadAll(file)
if err != nil {
io.WriteString(w, err.Error())
return
}
//Move to a temporary location
//This is allow us be able to get details like it's size and others
f, err := ioutil.TempFile("", header.Filename)
if err != nil {
panic("An error occurred while trying to create a temporary file")
}
val = validator.NewMimeTypeValidator([]string{"image/jpeg", "image/png"})
val2 = validator.NewSizeValidator((1024 * 1024 * 2), (200 * 1024)) //2MB(maxSize) and 200KB(minSize)
if _, err := val.Validate(f); err != nil {
panic("Validation failed")
}
if _, err := val2.Validate(f); err != nil {
panic("Validation failed")
}
//Upload to some place
fs = afero.NewMemMapFs() //Using an inmemory store here..
storeAdapter = storage.NewFilerStorage(fs, nil)
if err := storeAdapter.Write("some/path", f); err != nil {
panic("An error occurred while writing the file")
}
io.WriteString(w, "The upload was successful")
return
}
})
}License
MIT