feat: Implement client-side image compression and server-side rendering for image type sign items on PDF documents.

models/__init__.py

@@ -1,3 +1,3 @@
 # -*- coding: utf-8 -*-
-
 from . import sign_item_type
+from . import sign_document

models/sign_document.py

@@ -0,0 +1,159 @@
+# -*- coding: utf-8 -*-
+import base64
+import io
+from odoo import models, api
+from odoo.exceptions import ValidationError
+from odoo.tools.pdf import PdfFileReader, PdfFileWriter, PdfReadError
+from reportlab.pdfgen import canvas
+from reportlab.lib.utils import ImageReader
+from PIL import UnidentifiedImageError
+
+class SignDocument(models.Model):
+    _inherit = 'sign.document'
+
+    def render_document_with_items(self, signed_values=None, values_dict=None, final_log_hash=None):
+        # 1. Get the base output from super (standard + other modules)
+        base_output = super(SignDocument, self).render_document_with_items(signed_values, values_dict, final_log_hash)
+        
+        # If super returns None (e.g. encrypted PDF), we respect it.
+        if not base_output:
+            return base_output
+
+        # 2. Check if we have any 'image' items to render
+        items_by_page = self._get_sign_items_by_page()
+        has_image_items = any(
+            item.type_id.item_type == 'image'
+            for page_items in items_by_page.values()
+            for item in page_items
+        )
+
+        if not has_image_items:
+            return base_output
+
+        # 3. Load the base output into PdfFileReader
+        # base_output is a BytesIO
+        try:
+            base_pdf = PdfFileReader(base_output, strict=False)
+        except (ValueError, PdfReadError):
+            # Should not happen if super succeeded, but safety first
+            return base_output
+
+        if not signed_values:
+            signed_values, values_dict = self._get_preview_values()
+
+        # 4. Prepare a new canvas overlay for OUR items
+        packet = io.BytesIO()
+        # We need page size from the base_pdf (which might have been rotated/modified?)
+        # Actually super returns a PDF where pages are merged.
+        # We should use the same page size logic as original method.
+        # But wait, we iterate pages.
+        
+        # Let's see how original method creates canvas:
+        # can = canvas.Canvas(packet, pagesize=self._get_page_size(old_pdf))
+        # We need to replicate this per-page iteration to draw on the correct page.
+        
+        # Problem: canvas is one continuous stream of pages.
+        # We need to make a canvas that matches the page count and sizes of base_pdf.
+        
+        # However, we can just create a single canvas, add pages, and then merge.
+        # But we need the correct page size for each page.
+        
+        # Let's iterate base_pdf pages to get sizes.
+        
+        # Odoo's original code uses self._get_page_size(old_pdf) which returns MAX width/height.
+        # Then for each page it gets mediaBox.
+        
+        # We will do the same loop structure.
+        
+        can = canvas.Canvas(packet, pagesize=self._get_page_size(base_pdf))
+        
+        for p in range(0, base_pdf.getNumPages()):
+            page = base_pdf.getPage(p)
+            width = float(abs(page.mediaBox.getWidth()))
+            height = float(abs(page.mediaBox.getHeight()))
+            
+            # Rotation handling (same as original)
+            rotation = page.get('/Rotate', 0)
+            if rotation and isinstance(rotation, int):
+                can.rotate(rotation)
+                if rotation == 90:
+                    width, height = height, width
+                    can.translate(0, -height)
+                elif rotation == 180:
+                    can.translate(-width, -height)
+                elif rotation == 270:
+                    width, height = height, width
+                    can.translate(-width, 0)
+            
+            # Function to fix transparency (copied/imported from original or re-defined?)
+            # Since it's not exported, we re-define it or import if possible.
+            # _fix_image_transparency is not exported. We will redefine it helper.
+            
+            items = items_by_page.get(p + 1, [])
+            for item in items:
+                if item.type_id.item_type != 'image':
+                    continue
+                
+                value_dict = signed_values.get(item.id)
+                if not value_dict:
+                    continue
+                    
+                value = value_dict.get('value')
+                # For image type, value is the base64 image
+                if not value:
+                    continue
+
+                try:
+                    image_data = base64.b64decode(value[value.find(',') + 1:])
+                    image_reader = ImageReader(io.BytesIO(image_data))
+                except (UnidentifiedImageError, ValueError):
+                    # Skip invalid images
+                    continue
+                
+                # Setup transparency override if needed (simplified version)
+                # We can try to access the protected method if we really want, but let's implement the logic.
+                if hasattr(image_reader, '_image'):
+                     _fix_image_transparency(image_reader._image)
+
+                can.drawImage(
+                    image_reader,
+                    width * item.posX,
+                    height * (1 - item.posY - item.height),
+                    width * item.width,
+                    height * item.height,
+                    'auto',
+                    True
+                )
+            
+            can.showPage()
+            
+        can.save()
+        
+        # 5. Merge our new overlay with the base_pdf
+        item_pdf = PdfFileReader(packet)
+        new_pdf = PdfFileWriter()
+
+        for p in range(0, base_pdf.getNumPages()):
+            page = base_pdf.getPage(p)
+            # Merge the overlay
+            if p < item_pdf.getNumPages():
+                page.mergePage(item_pdf.getPage(p))
+            new_pdf.addPage(page)
+
+        output = io.BytesIO()
+        try:
+            new_pdf.write(output)
+        except PdfReadError:
+            raise ValidationError(self.env._("There was an issue generating the document."))
+
+        return output
+
+def _fix_image_transparency(image):
+    # Copied from sign/models/sign_document.py
+    if image.mode != 'RGBA':
+        return
+    pixels = image.load()
+    for x in range(image.size[0]):
+        for y in range(image.size[1]):
+            if pixels[x, y] == (0, 0, 0, 0):
+                pixels[x, y] = (255, 255, 255, 0)

static/src/js/sign_image_upload.js

@@ -47,29 +47,75 @@ patch(SignablePDFIframe.prototype, {
             input.addEventListener('change', (e) => {
                 const file = e.target.files[0];
                 if (!file) return;
+
                 const reader = new FileReader();
-                reader.onload = () => {
+                reader.onload = (readerEvent) => {
-                    const result = reader.result;
+                    const img = new Image();
-                    signItem.el.dataset.value = result;
+                    img.onload = () => {
-                    // Manually update the DOM to show the image
+                        // Create a canvas for compression
-                    const img = signItem.el.querySelector('img');
+                        const canvas = document.createElement('canvas');
-                    if (img) {
+                        let width = img.width;
-                        img.src = result;
+                        let height = img.height;
+
+                        // Calculate new dimensions (e.g., max width/height 1920 to keep it reasonable)
+                        const MAX_SIZE = 1920;
+                        if (width > height) {
+                            if (width > MAX_SIZE) {
+                                height *= MAX_SIZE / width;
+                                width = MAX_SIZE;
+                            }
                         } else {
+                            if (height > MAX_SIZE) {
+                                width *= MAX_SIZE / height;
+                                height = MAX_SIZE;
+                            }
+                        }
+
+                        canvas.width = width;
+                        canvas.height = height;
+
+                        const ctx = canvas.getContext('2d');
+                        ctx.drawImage(img, 0, 0, width, height);
+
+                        // Compress to JPEG with 0.7 quality
+                        const compressedDataUrl = canvas.toDataURL('image/jpeg', 0.7);
+
+                        // Set the value on the element
+                        // Use a specific attribute or just data-value which is used by getSignatureValue
+                        // We also need to add a hidden input or update state if Odoo framework expects it
+
+                        // Update the internal state which Odoo Sign might be using
+                        signItem.data.value = compressedDataUrl;
+                        signItem.el.dataset.value = compressedDataUrl;
+
+                        // Display the image
                         // Remove placeholder if it exists
                         const placeholder = signItem.el.querySelector('.o_placeholder');
                         if (placeholder) placeholder.remove();
 
+                        // Remove existing image
+                        const existingImg = signItem.el.querySelector('img');
+                        if (existingImg) existingImg.remove();
+
                         const newImg = document.createElement('img');
-                        newImg.src = result;
+                        newImg.src = compressedDataUrl;
                         newImg.style.maxWidth = '100%';
                         newImg.style.maxHeight = '100%';
                         newImg.style.objectFit = 'contain';
 
-                        signItem.el.appendChild(newImg);
+                        // Append to a specific container if needed, or just to el
-                    }
+                        // sign_item_body is usually where content goes
+                        const body = signItem.el.querySelector('.sign_item_body') || signItem.el;
+                        body.appendChild(newImg);
 
-                    this.handleInput(); // Trigger validation check
+                        this.signItemValues[signItem.id] = compressedDataUrl;
+
+                        // Trigger validation/saving mechanism
+                        // We might need to call a method to notify Odoo that value changed
+                        // In standard sign, usually it listens to input or checks dirty state.
+                        // Setting data-value is what getSignatureValueFromElement checks (based on our other patch)
+                    };
+                    img.src = readerEvent.target.result;
                 };
                 reader.readAsDataURL(file);
             });
@@ -78,7 +124,7 @@ patch(SignablePDFIframe.prototype, {
 
     getSignatureValueFromElement(item) {
         if (item.data.type === 'image') {
-            return item.el.dataset.value || false;
+            return item.el.dataset.value || item.data.value || false;
         }
         return super.getSignatureValueFromElement(item);
     }