feat: add value check

[gusinacio]

This PR aims to create the value check for indexer-service. This means that our system checks if the gateway is sending the value that we are requesting, otherwise it rejects the query.

Initially, I was planning to do a cache system to allow queries that contain the older cost model but it exploded really fast in complexity.

Given conversations with indexers, they seemed to not care to lose a few queries during 30 seconds until the gateway fetches again the cost model.

In case this becomes a problem to indexers, we can implement it again.

[github-actions]

Pull Request Test Coverage Report for Build 11505248479

Details

• 273 of 448 (60.94%) changed or added relevant lines in 15 files are covered.
• 2 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-1.3%) to 71.373%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
common/src/tap/checks/allocation_eligible.rs	0	1	0.0%
common/src/tap/checks/sender_balance_check.rs	0	1	0.0%
service/src/service.rs	0	1	0.0%
tap-agent/src/tap/context/checks/value.rs	0	1	0.0%
common/src/cost_model.rs	146	148	98.65%
common/src/tap.rs	0	2	0.0%
service/src/routes/cost.rs	0	2	0.0%
common/src/indexer_service/http/request_handler.rs	0	14	0.0%
common/src/tap/checks/value_check.rs	95	246	38.62%

Files with Coverage Reduction	New Missed Lines	%
common/src/indexer_service/http/request_handler.rs	2	0.0%

Totals
Change from base Build 11488787549:	-1.3%
Covered Lines:	5101
Relevant Lines:	7147

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💛 - Coveralls

[aasseman]

Having the cache in the indexer-service raises a small risk though.
We treat indexer-service as a stateless service. So in the case an indexer-service was recently started, it wouldn't be aware of previous recent agora models, and that could lead to wrongly rejecting queries.
However the only other solution to this would be to have the indexer DB do the caching of models, which could be annoying to implement.

[suchapalaver]

This looks good to me @gusinacio , a lot of work in the making!

I think the tests could be made more defensive and clearer about intention, but I understand some of the limitations we're facing with testing and I trust this has been tested extensively observationally.

[anirudh2]

Great work, @gusinacio! Lot's of great stuff in here. None of my requests are necessarily blocking, so I'm going to approve the PR. Your call whether to address them or not.

[anirudh2]

The naming can be somewhat arbitrary. For example, here, you have a getter get_expected_value, but in cost_model.rs, you have getters named cost_models and cost_model.

[anirudh2]

Good with either, but just pick one.

[gusinacio]

We have cost_models and cost_model there because they map to GraphQL queries that indexer-service has.

I usually use get_ but it's a Java mind hahaha, maybe a future refactor I should remove all getters into more meaningful names.

[anirudh2]

I love that you thumbs-up'ed your own comment hahaha. Glad you agree with yourself 😂

[anirudh2]

Thanks, @gusinacio!