Upload Library

The upload library handles file uploads with validation and image processing.

Basic Upload

import "goigniter/system/libraries"

func (p *Product) Upload() {
    c := p.Ctx

    upload, err := libraries.NewUpload(c.Request(), "file", "./public/uploads", "images")
    if err != nil {
        c.JSON(400, core.Map{"error": err.Error()})
        return
    }

    c.JSON(200, core.Map{
        "filename": upload.Filename,
        "path":     upload.Path,
        "size":     upload.Size,
    })
}

Parameters:

• c.Request() — the HTTP request
• "file" — form field name
• "./public/uploads" — destination directory
• "images" — allowed file type group

Allowed File Types

File type groups determine which files are accepted:

// Upload images only
libraries.NewUpload(c.Request(), "avatar", "./uploads", "images")
// images: jpg, jpeg, png, gif, webp

// Upload documents
libraries.NewUpload(c.Request(), "file", "./uploads", "docs")
// docs: pdf, doc, docx, xls, xlsx, txt

// Upload archives
libraries.NewUpload(c.Request(), "archive", "./uploads", "archives")
// archives: zip, rar, tar, gz

Caution

Files uploaded to public/ are served from your app’s own domain. Files that browsers execute (HTML, SVG, JavaScript) are therefore always rejected, even if you allow them explicitly: they could run scripts as the logged-in user (stored XSS). An upload without an explicit list of allowed extensions is rejected too. Use random file names so uploads cannot be guessed.

Validation

The uploader validates:

• File type (based on group)
• File size (default: 2MB)

upload, err := libraries.NewUpload(c.Request(), "file", "./uploads", "docs")
if err != nil {
    // Invalid file type or size exceeded
    c.JSON(400, core.Map{"error": err.Error()})
    return
}

Image Processing

Resize images after upload:

// Resize to specific dimensions (maintains aspect ratio)
err := upload.Resize(800, 600)

// Resize to thumbnail
path, err := upload.Thumbnail(150, 150)

// Crop from center
path, err := upload.Crop(300, 300)

The image is saved as a new file in the same directory with a suffix:

• Resize → photo_800x600.jpg
• Thumbnail → photo_thumb.jpg
• Crop → photo_cropped.jpg

Complete Example

func (p *Product) UploadImage() {
    c := p.Ctx

    upload, err := libraries.NewUpload(c.Request(), "file", "./public/uploads", "images")
    if err != nil {
        c.JSON(400, core.Map{"error": err.Error()})
        return
    }

    // Create thumbnail
    thumbPath, _ := upload.Thumbnail(150, 150)

    c.JSON(200, core.Map{
        "filename":    upload.Filename,
        "path":        upload.Path,
        "thumbnail":   thumbPath,
        "size":        upload.Size,
    })
}

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