Using an or expression with a knn expression raises a ResponseError with a Syntax error

[RogerThomas]

I am trying to use the tags feature along with KNN vector search, so for example, a query searching for all albums where

(Genre:rock AND Decade: 60s) OR (Genre:rock AND Decade: 70s)

Along with a KNN vector search.

Querying on just the expression above is fine, however when I combine this with a KNN search, I get the following error:

redis.exceptions.ResponseError: Syntax error at offset 84 near >[

Code to reproduce

import numpy as np
from redis_om import Field, JsonModel, VectorFieldOptions, Migrator, KNNExpression


class Album(JsonModel):
    title: str = Field(primary_key=True)
    tags: str = Field(index=True)
    title_embeddings: list[float] = Field(
        index=True,
        vector_options=VectorFieldOptions.flat(
            type=VectorFieldOptions.TYPE.FLOAT32,
            dimension=2,
            distance_metric=VectorFieldOptions.DISTANCE_METRIC.COSINE,
        ),
    )


def embedding_function(text: str) -> [float]:
    """Mock embedding fnction, just counts vowels/consonants and normalises"""
    vowels = "aeiouAEIOU"
    num_vowels = sum((char in vowels) for char in text)
    num_consonants = len(text) - num_vowels
    x = num_vowels / len(text)
    y = num_consonants / len(text)
    norm = (x * x + y * y) ** 0.5
    xdim = x / norm
    ydim = y / norm
    vector = [round(xdim, 9), round(ydim, 9)]
    return vector


def main():
    Migrator().run()
    album_tuples = [
        ("The Dark Side Of The Moon", ["Genre:prog-rock", "Decade:70s"]),
        ("Rumours", ["Genre:rock", "Decade:70s"]),
        ("Abbey Road", ["Genre:rock", "Decade:60s"]),
    ]
    for title, tags in album_tuples:
        album = Album(
            title=title,
            tags="|".join(tags),
            title_embeddings=embedding_function(title),
        )
        album.save()

    expression = (Album.tags == "Genre:rock|Decade:70s") | (Album.tags == "Genre:rock|Decade:60s")
    knn_expression = KNNExpression(
        k=3,
        vector_field=Album.__fields__["title_embeddings"],
        reference_vector=np.array(embedding_function("Hotel California"), dtype="f4").tobytes()
    )
    # ---------------------------------------------------------------------------------------------
    # Query 1, Query on Tags only
    # ---------------------------------------------------------------------------------------------
    print("\nRunning Query 1, Tags only")
    albums = Album.find(expression).all()
    for album in albums:
        print(album)

    # ---------------------------------------------------------------------------------------------
    # Query 2, Query on KNN only
    # ---------------------------------------------------------------------------------------------
    print("\nRunning Query 2, KNN only")
    albums = Album.find(knn=knn_expression).all()
    for album in albums:
        print(album)

    # ---------------------------------------------------------------------------------------------
    # Query 2, Query on Tags and KNN
    # ---------------------------------------------------------------------------------------------
    print("\nRunning Query 2, KNN only")
    albums = Album.find(expression, knn=knn_expression).all()
    for album in albums:
        print(album)


if __name__ == "__main__":
    main()

This will fail on this line

    albums = Album.find(expression, knn=knn_expression).all()