# Unable to return object property when datatype is Blob

**URL:** <https://forum.weaviate.io/t/unable-to-return-object-property-when-datatype-is-blob/1522>\
**Category:** Support\
**Tags:** python\
**Created:** [February 19, 2024, 4:25pm UTC](https://forum.weaviate.io/t/unable-to-return-object-property-when-datatype-is-blob/1522 "2024-02-19T16:25:41Z")\
**Posts on this page:** 7\
**Page:** 1

<div class="post-metadata">

**Author:** ![birdboy](https://avatars.discourse-cdn.com/v4/letter/b/919ad9/32.png) [@birdboy](https://forum.weaviate.io/u/birdboy)\
**Post date:** [February 19, 2024, 4:25pm UTC](https://forum.weaviate.io/t/unable-to-return-object-property-when-datatype-is-blob/1522/1 "2024-02-19T16:25:41Z")

</div>

### Description

I am using the `img2vec-neural` vectorizer to embed images in my collection. As stated in the docs, I have defined a property with the Blob datatype to hold the base64 representation of the image and referenced that property in the `image_fields` argument.

```auto
return self.client.collections.create(
    name=IMAGES_COLLECTION_NAME,
    vectorizer_config=wvc.Configure.Vectorizer.img2vec_neural(image_fields=["image"]),
    vector_index_config=wvc.Configure.VectorIndex.hnsw(distance_metric=wvc.VectorDistance.COSINE),
    properties=[
        wvc.Property(name="name", data_type=wvc.DataType.TEXT, skip_vectorization=True),
        wvc.Property(name="image", data_type=wvc.DataType.BLOB),
    ],
)

```

I then use the `insert` method to create and add objects to my collection.

```auto
image_properties = {
    "text": image.text,
    "image": image.image_b64,
}
image_uuid = generate_uuid5(image_properties)
self._images.data.insert(properties=image_properties, uuid=image_uuid)

```

Finally, when performing a similarity search, I get accurate results in the sense that similar image objects are indeed found however, I cannot return the image property.

```auto
reference_images = self._images.query.near_image(
    near_image=image.image_b64,
    limit=3,
    return_metadata=wvc.MetadataQuery(distance=True),
).objects

```

Without `return_properties` defined, it should return all properties but it instead only returns `name`. Even when I do define it

```auto
return_properties=["name", "image"]

```

it just comes back as `None`.

So I’m wondering if there is a limitation given how blob types are stored that prevents them from being served in queries as I also tried duplicating the `image` property, just calling it `image2` for simplicity, stored it as a blob but chose to skip vectorization and it too could not be returned in a query. So it seems to be a limitation on the blob type as opposed to an issue with blob types which are vectorized.

Essentially I assumed this would behave as `text2vec-transformers` does and when I query the collection it returns the property, say `text`, that was vectorized. The docs don’t seem to provide a direct example demonstrating this as possible but the definition of the [blob](https://weaviate.io/developers/weaviate/config-refs/datatypes#datatype-blob) type states `When serving, the data is base64 encoded (so it is safe to serve as json)` which seems to imply that I should be able to access the data somehow.

Any help or insight would be appreciated. Thanks!

### Server Setup Information

- Weaviate Server Version: 1.23.2
- Deployment Method: Docker
- Multi Node? Number of Running Nodes: N/A
- Client Language and Version: Python v4

### Any additional Information

This Weaviate [article](https://weaviate.io/blog/how-to-build-an-image-search-application-with-weaviate) seems to sidestep this issue by including a filepath to the image, which has been my current solution up until this point, but for my use case I ultimately would just want the images stored and accessible through Weaviate.

---

<div class="post-metadata">

**Author:** ![DudaNogueira](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.weaviate.io/dudanogueira/32/7846_2.png) [@DudaNogueira](https://forum.weaviate.io/u/DudaNogueira)\
**Post date:** [February 19, 2024, 5:54pm UTC](https://forum.weaviate.io/t/unable-to-return-object-property-when-datatype-is-blob/1522/2 "2024-02-19T17:54:40Z")

</div>

Hi @birdboy ! Welcome to our community 🤗

You shouldn’t be using Server 1.23.2 with python client 4.4.4

here we have a compatibility matrix:

> **[Python | Weaviate - Vector Database](https://weaviate.io/developers/weaviate/client-libraries/python#client-releases)**
>
> Overview

With that said, can you confirm this issue will happen with latest 1.23.9 version of the Weaviate server?

Let me know if this is the case, then I can try replicating this.

But probably, a newer version of the server will fix this.

Thanks!

---

<div class="post-metadata">

**Author:** ![sebawita](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.weaviate.io/sebawita/32/5_2.png) [@sebawita](https://forum.weaviate.io/u/sebawita)\
**Post date:** [February 19, 2024, 7:50pm UTC](https://forum.weaviate.io/t/unable-to-return-object-property-when-datatype-is-blob/1522/3 "2024-02-19T19:50:00Z")

</div>

Hi @birdboy,

> [@birdboy](#):
>
> Without `return_properties` defined, it should return all properties but it instead only returns `name`. Even when I do define it

The Python client v4, doesn’t return blob properties by default, as these are potentially large values.  
However, if you run a query with `return_properties`, I would expect values for the selected properties to be present.

Is this how you run your query?

```python
reference_images = self._images.query.near_image(
    near_image=image.image_b64,
    limit=3,
    return_properties=["name", "image"],
    return_metadata=wvc.MetadataQuery(distance=True),
).objects

```

Also, did you try upgrading Weaviate to 1.23.9 or later?

---

<div class="post-metadata">

**Author:** ![birdboy](https://avatars.discourse-cdn.com/v4/letter/b/919ad9/32.png) [@birdboy](https://forum.weaviate.io/u/birdboy)\
**Post date:** [February 19, 2024, 8:20pm UTC](https://forum.weaviate.io/t/unable-to-return-object-property-when-datatype-is-blob/1522/4 "2024-02-19T20:20:11Z")

</div>

Thanks for the replies! I upgraded to 1.23.9 however, it unfortunately did not change the current behavior.

@sebawita, that is good to know regarding blobs not being returned by default but yes, that is how I am running my query (with `return_properties` explicitly included).

Also, when checking the types of the properties when they are returned, I see `name` as `<class 'str'>` which is expected, but `image` comes back as `<class 'v1.properties_pb2.Value'>`. Is this expected and I’m just not parsing the results properly, or is this more so an indication that the property is not recognized?

Thanks again!

---

<div class="post-metadata">

**Author:** ![DudaNogueira](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.weaviate.io/dudanogueira/32/7846_2.png) [@DudaNogueira](https://forum.weaviate.io/u/DudaNogueira)\
**Post date:** [February 19, 2024, 10:40pm UTC](https://forum.weaviate.io/t/unable-to-return-object-property-when-datatype-is-blob/1522/5 "2024-02-19T22:40:51Z")

</div>

Hi @birdboy !

I was able to get the blob returned. He is the code I used based on yours:

```auto
import weaviate
from weaviate import classes as wvc
client = weaviate.connect_to_local()

client.collections.delete("Teste")
c = client.collections.create(
    "Teste",
    vectorizer_config=wvc.config.Configure.Vectorizer.img2vec_neural(image_fields=["image"]),
    vector_index_config=wvc.config.Configure.VectorIndex.hnsw(distance_metric=wvc.config.VectorDistances.COSINE),
    properties=[
        wvc.config.Property(name="name", data_type=wvc.config.DataType.TEXT, skip_vectorization=True),
        wvc.config.Property(name="image", data_type=wvc.config.DataType.BLOB),
    ],
)

c.config.get().properties

b64 = "iVBORw0KGgoAAAANSUh......"

b64_2 = "iVBOR......"

from weaviate.util import generate_uuid5
image_properties = {
    "name": "Some text",
    "image": b64,
}
image_uuid = generate_uuid5(image_properties)
c.data.insert(properties=image_properties, uuid=image_uuid)

c.query.fetch_objects(return_properties=["name", "image"], include_vector=True).objects[0].properties

# {'image': 'iVBORw0KGgoAAAANSU.......',
# 'name': 'Some text'}

reference_images = c.query.near_image(
    near_image=b64_2,
    limit=3,
    return_properties=["name", "image"],
    return_metadata=wvc.query.MetadataQuery(distance=True),
    include_vector=True,
).objects

print(reference_images[0].properties)

```

Note: some imports have changed. I adapted that accordingly in the code.

Let me know if that helps 🙂

---

<div class="post-metadata">

**Author:** ![birdboy](https://avatars.discourse-cdn.com/v4/letter/b/919ad9/32.png) [@birdboy](https://forum.weaviate.io/u/birdboy)\
**Post date:** [February 20, 2024, 3:19am UTC](https://forum.weaviate.io/t/unable-to-return-object-property-when-datatype-is-blob/1522/6 "2024-02-20T03:19:28Z")

</div>

Hi @DudaNogueira ,

So I tried running the code you provided and still am unable to get the image data to return.

Here’s what I see

```auto
{'image': , 'name': 'Some text'}

```

Here is my docker-compose file in case there is some issue with it, though it is just the file generated by the [configurator](https://weaviate.io/developers/weaviate/installation/docker-compose#configurator) tool

```auto
---
version: '3.4'
services:
  weaviate:
    command:
    - --host
    - 0.0.0.0
    - --port
    - '8080'
    - --scheme
    - http
    image: semitechnologies/weaviate:1.23.9
    ports:
    - 8080:8080
    - 50051:50051
    volumes:
    - weaviate_data:/var/lib/weaviate
    restart: on-failure:0
    environment:
      IMAGE_INFERENCE_API: 'http://i2v-neural:8080'
      QUERY_DEFAULTS_LIMIT: 25
      AUTHENTICATION_ANONYMOUS_ACCESS_ENABLED: 'true'
      PERSISTENCE_DATA_PATH: '/var/lib/weaviate'
      DEFAULT_VECTORIZER_MODULE: 'img2vec-neural'
      ENABLE_MODULES: 'img2vec-neural'
      CLUSTER_HOSTNAME: 'node1'
  i2v-neural:
    image: semitechnologies/img2vec-pytorch:resnet50
    environment:
      ENABLE_CUDA: '0'
volumes:
  weaviate_data:
...

```

Oh and probably made clear given the docker-compose file but I am running CPU-only as I’m on a M2 Macbook (I’m doubtful this would have an impact on this particular issue however)

---

<div class="post-metadata">

**Author:** ![birdboy](https://avatars.discourse-cdn.com/v4/letter/b/919ad9/32.png) [@birdboy](https://forum.weaviate.io/u/birdboy)\
**Post date:** [February 20, 2024, 6:36am UTC](https://forum.weaviate.io/t/unable-to-return-object-property-when-datatype-is-blob/1522/7 "2024-02-20T06:36:41Z")

</div>

**UPDATE** :

Thanks again for the help troubleshooting this. Oddly, I was able to get it to work by not specifying the `image` property in the schema. I still define it here

```auto
vectorizer_config=wvc.config.Configure.Vectorizer.img2vec_neural(image_fields=["image"])

```

but **not** in the `properties` list

```auto
wvc.config.Property(name="image", data_type=wvc.config.DataType.BLOB)

```

After some investigating it seems to be working because auto-schema is inferring that the image property is of type `Text`. I have tried manually setting the datatype to `Text` and it works as well. Interestingly, it does not seem to change my image querying results but regardless, the docs explicitly advise against this

```auto
dataType - the data type of the property. For use in imageFields, must be set to blob.

```

So while this is an interesting development, it is not my desired work-around.