Resolving GDAL Version Mismatch in GeoDjango 5.1

Based on your error message, it appears that Django 5.1 is looking for GDAL versions 3.0 through 3.8, but you have GDAL 3.9 installed. This version mismatch is causing the error.

Solution: Set GDAL_LIBRARY_PATH in Your Settings

The most straightforward solution is to explicitly tell Django where to find your GDAL library by setting the GDAL_LIBRARY_PATH in your Django settings file (settings.py):

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# Add this to your settings.py file
GDAL_LIBRARY_PATH = r'C:\OSGeo4W\bin\gdal309.dll'

Make sure to adjust the path if your OSGeo4W installation is in a different location. The typical default location is C:\OSGeo4W\bin\, but you should verify this on your system.

Additional Environment Configuration

Also ensure that your Windows environment variables are properly set up as mentioned in the documentation:

set OSGEO4W_ROOT=C:\OSGeo4W
set GDAL_DATA=%OSGEO4W_ROOT%\apps\gdal\share\gdal
set PROJ_LIB=%OSGEO4W_ROOT%\share\proj
set PATH=%PATH%;%OSGEO4W_ROOT%\bin

You can add these permanently to your system by running the following commands in an administrator command prompt:

reg ADD "HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Environment" /v Path /t REG_EXPAND_SZ /f /d "%PATH%"
reg ADD "HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Environment" /v GDAL_DATA /t REG_EXPAND_SZ /f /d "%GDAL_DATA%"
reg ADD "HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Environment" /v PROJ_LIB /t REG_EXPAND_SZ /f /d "%PROJ_LIB%"

Remember to restart your computer after making these changes for them to take effect.

Alternative: Set Library Path in Python Code

If you prefer not to modify your settings file, you can also set the library path in your code before Django attempts to load GDAL:

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import os
os.environ['GDAL_LIBRARY_PATH'] = r'C:\OSGeo4W\bin\gdal309.dll'

This approach can be useful for testing or if you need different configurations in different environments.

Note that while Django 5.1 documentation lists supported GDAL versions up to 3.8, newer versions like 3.9 may work fine once you explicitly set the library path.

Accessing Product Features Through Price Model

Yes, you can access the many-to-many features for a product through the Price model using reverse lookups, but there are a few issues in your current implementation that need to be fixed.

Issues in Your Code

1. In your template, you're trying to access price.Product.features, but your field is actually named product (lowercase) in the Price model.

2. In your Product model, you've defined the field as feature (singular) but set the related_name to features (plural), which can be confusing.

3. There's a typo in your Price model: on_delete=models.CASCADEm should be on_delete=models.CASCADE.

Correct Way to Access Features

Here's how you should access the features in your template:

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<div class="info">
    {% for feature in price.product.feature.all %}
        <p>{{ feature }}</p>
    {% endfor %}
</div>

The key points:

• Use lowercase product to match your model field name
• Use feature (singular) as defined in your Product model
• Call .all() to get all related features
• Iterate through them to display each feature

Alternative Approach

If you prefer to use the related_name you defined, you could also access it like this:

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<div class="info">
    {% for feature in price.product.feature.all %}
        <p>{{ feature }}</p>
    {% endfor %}
</div>

Model Improvements

For better clarity, I recommend making these changes to your models:

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class Product(models.Model):
    # ...
    features = models.ManyToManyField(Features, related_name='products')
    # ...

Then in your template:

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<div class="info">
    {% for feature in price.product.features.all %}
        <p>{{ feature }}</p>
    {% endfor %}
</div>

This makes the naming more consistent (plural for collections) and the related_name more intuitive (a feature belongs to multiple products).

You don't need to modify your view to fetch these features separately - Django's ORM will handle the relationship traversal for you.