Supports tags filter for nodes

[kompotkot]

Changes

Nobebalancer support of filter by tag.

How to test these changes?

Tested locally

Related issues

[kompotkot]

@bugout-dev check

• Merge and deploy in prod config with tags

[zomglings]

I tested locally using the modifications on this branch: #747

My config (~/.nodebalancer/config.json):

[
  {
    "blockchain": "ethereum",
    "endpoint": "<Infura URL>",
    "tags": ["infura"]
  },
  {
    "blockchain": "polygon",
    "endpoint": "<Infura URL>",
    "tags": ["infura"]
  },
  {
    "blockchain": "polygon",
    "endpoint": "<Alchemy URL>",
    "tags": ["alchemy"]
  }
]

When I ran this request, I sometimes got the Infura URL in the x-node-url response header and sometimes the Alchemy URL:

curl -v --request POST "http://127.0.0.1:8544/nb/polygon/jsonrpc?access_id=$NB_CONTROLLER_ACCESS_ID&data_source=blockchain&tags=alchemy" \
    --header 'Content-Type: application/json' \
    --data-raw '{
        "jsonrpc":"2.0",
        "method":"eth_blockNumber",
        "id":1
    }'

Am I using the wrong query parameter?

[zomglings]

@kompotkot : I think it needs documentation for how to use tags, and I think you can probably also write unit tests for the node selection function.

The unit tests are currently failing. This should be fixed, as well. If necessary, remove tests, but there should be a working test framework.

[zomglings]

@kompotkot : My bad. I was using tags for query parameter when I should have used tag.

This request is working well:

curl -v --request POST "http://127.0.0.1:8544/nb/polygon/jsonrpc?access_id=$NB_CONTROLLER_ACCESS_ID&data_source=blockchain&tag=alchemy" \
    --header 'Content-Type: application/json' \
    --data-raw '{
        "jsonrpc":"2.0",
        "method":"eth_blockNumber",
        "id":1
    }'

[Andrei-Dolgolev]

Looks correct