Missing `get_by_ids` Implementation in `ElasticsearchStore`

[istvancsabakis]

Description:

The ElasticsearchStore class within the langchain_elasticsearch package currently lacks an implementation for the get_by_ids method. Attempting to use this method results in a NotImplementedError.

Error Details:

When calling get_by_ids with a list of IDs, such as ["1"], the following error is raised:

NotImplementedError: ElasticsearchStore does not yet support get_by_ids.

Steps to Reproduce:

1. Create an instance of ElasticsearchStore with the necessary parameters:

   from langchain_elasticsearch import ElasticsearchStore 
   from langchain_openai import OpenAIEmbeddings
   
   store = ElasticsearchStore("test", embedding=OpenAIEmbeddings(), es_url="http://localhost:9200")

2. Attempt to retrieve documents by using their IDs:

   store.get_by_ids(["1"])

3. Observe the NotImplementedError that indicates the method is not currently supported.

Expected Behavior:

The get_by_ids method should allow retrieval of documents from the ElasticsearchStore using their unique IDs without raising an error.

Actual Behavior:

A NotImplementedError is raised, indicating that the method is not supported.

Request for Enhancement:

Please implement the get_by_ids method in the ElasticsearchStore class to allow for the retrieval of documents by their IDs.

Thank you for your assistance!

[jstoneman-ME]

Has there been any progress?