[FEATURE] Pulling fields content for neural search from user provided URL

[martin-gaievski]

Is your feature request related to a problem?

Today the content for the text and images for mutimodal semantic search is provided directly with the request in form of base64 encoded string. This requires additional per-processing of data and not be optimal is some scenarios when for instance data is already available in some other system. Another problem is storage space, in OpenSearch this binary content will be stored as part of the index.

What solution would you like?

Allow URLs for fields, something around these lines:

  "query": {
        "neural": {
              "vector_embeddings": {
                  "query": {
                        "image":  {
                            "value": "http://myserver/image1.jpg"
                            "type": "url"
                        },

What alternatives have you considered?

Alternative is available now, user needs to download content from the URL and do base64 encoding

Do you have any additional context?

There can be concerns around security as system will be pulling from remote URLs. Most probably the syntax of existing requests will change to support url type