WIP on threadpool impl of query_namespaces

[jhamon]

Problem

I need a non-async interface providing a similar functionality as the query_namespaces currently implemented in GRPCIndexAsyncio.

Solution

Background info:

• The multiprocessing ThreadPool is currently setup during the instantiation of Index. The constructor takes a param for number of pool_threads with a default value of 1.
• When calling query with optional kwarg, async_req=True, the underlying (generated from openapi spec) code will execute the request using pool.apply_async. The result of these calls is an ApplyResult[QueryResult]. To get the results, from these we call .get() on the ApplyResult.

New query_namespaces on Index:

• Copy some basic edge case stuff from the asyncio implementation. E.g. must have namespaces arg.
• For each namespace, call query with async_req=True
• Gather the resulting ApplyResults into a results array
• Pass these results into QueryResultsAggregator, recently implemented and tested in [Feat] asyncio for grpc data interactions #398
• It's expected this will be slower than the Asyncio implementation because we can't begin building the combined results heap until all requests have completed
• Added some retry logic for requests made with thread pools

Todo:

• Performance testing

Usage

from pinecone import Pinecone
import random

pc = Pinecone(
    api_key=os.environ['PINECONE_API_KEY'],
)

index = pc.Index(
    host="https://indexhost/",
    pool_threads=10
)

query_vec = [random.random()] * dimension

combined_results = index.query_namespaces(
    vector=query_vec,
    namespaces=["ns1", "ns2", "ns3", "ns4"],
    include_values=True,
    include_metadata=True,
    filter={"publication_date": {"$eq":"Last3Months"}},
    top_k=100
)

Dev build for manual testing

• pip install pinecone==6.0.0.dev3

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update
• Infrastructure change (CI configs, etc)
• Non-code change (docs, etc)
• None of the above: (explain here)

Test Plan

Describe specific steps for validating this change.

[harsha2010]

I'm not a python expert, but isn;t there some library that provides a decorator to retry functions? seems like this should be a solved problem

[jhamon]

There's nothing in the standard library afaik, and I'm very hesitant to add third-party dependencies because of the overall dependency hell situation in python.

[harsha2010]

what is this magic number 10?

[jhamon]

It's just a default value. Could be anything, but the API requires a value to be passed.

[jhamon]

Pursuing this in a different branch #409