Why does it work in the container but fail in Odoo?

When you run code in Odoo:

• Odoo may monkey-patch certain libraries (e.g., requests, image handling, base64 encoding).

• Odoo often runs under a different user, environment variables, or restricted execution context than the interactive Python shell.

• The io.BytesIO object or file pointer may be altered (e.g., closed, truncated, or empty) before Image.open() reads it.

Possible causes

Truncated or altered content

• Odoo’s import mechanism may manipulate the content before passing it to Pillow.

• If iter_content or content is re-read multiple times, the BytesIO buffer can be empty.

Pillow plugin mismatch

• The same Pillow version (11.2.1) is reported, but Odoo could be running with disabled or missing WebP plugin if Pillow was compiled differently.

• Some Odoo workers could be using a system-level Pillow without WebP support.

Different error handling for WebP

• Odoo’s image processing pipeline sometimes pre-converts images (e.g., using base64, tools.image_process). This can strip unsupported formats.

Threaded environment or lazy loading

• In multi-threaded environments, race conditions on BytesIO can cause UnidentifiedImageError.

Debugging steps

A. Check the content length inside Odoo

Before Image.open, verify if the buffer has data:

print(len(content))

If 0, the buffer is empty when Odoo executes it.

B. Save the file temporarily to check integrity

with open("/tmp/test.webp", "wb") as f:
    f.write(content)

Then manually run Image.open("/tmp/test.webp"). If it opens, Odoo is altering BytesIO.

C. Explicitly load and verify the image

image = Image.open(io.BytesIO(content))
image.load()  # Force full loading
image.verify()

This can help pinpoint lazy loading issues.

D. Check Pillow features at runtime inside Odoo

from PIL import features
print("WebP support:", features.check('webp'))

If this returns False inside Odoo, it’s a plugin issue.

4. Fixes

Option 1: Ensure content is not re-read

When using iter_content, ensure the stream isn’t consumed twice:

res = requests.get(url, stream=True)
content = res.content  # instead of iter_content
image = Image.open(io.BytesIO(content))

Option 2: Upgrade or recompile Pillow with WebP support

Ensure Pillow in the container supports WebP:

apt-get install libwebp-dev
pip install --force-reinstall pillow

Option 3: Use Odoo’s own image tools (avoiding direct Image.open)

Odoo provides tools.image_process which handles WebP gracefully (it may auto-convert to PNG):

from odoo.tools import image_process
image_data = image_process(content)

Option 4: Patch Odoo import code

If Odoo’s import pipeline uses BytesIO incorrectly, add a copy:

buffer = io.BytesIO(content)
buffer.seek(0)
image = Image.open(buffer)

5. Why is it only failing for WebP?

• WebP images are more sensitive to truncation; a small byte mismatch can make Pillow fail.

• Odoo sometimes converts WebP → PNG using an intermediate library, and if this fails silently, you’ll get an empty buffer.

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Have already tried those. and still same issue.

in debugger attached to container (using debugpy) got error :

In same container but directly in shell (No error) :

It's like if something in odoo is causing the error.