feat: support aggregator capabilities in aggregator discovery

[jpraynaud]

Content

This PR includes support or aggregator capabilities in the aggregator discovery process.

The capabilities of the discovered aggregators are now available in the CLI output. This command:

./mithril-client --unstable tools discover-aggregator pre-release-preview

Will output:

Mithril Client CLI version: 0.12.38
+-----------------------------------------------------------------------+--------------------------+-----------------------------------------------------------------------------------------------------------------+
| Aggregator Endpoint                                                   | Aggregate Signature Type | Signed Entity Types                                                                                             |
+-----------------------------------------------------------------------+--------------------------+-----------------------------------------------------------------------------------------------------------------+
| https://aggregator.pre-release-preview.api.mithril.network/aggregator | Concatenation            | MithrilStakeDistribution,CardanoStakeDistribution,CardanoImmutableFilesFull,CardanoDatabase,CardanoTransactions |
+-----------------------------------------------------------------------+--------------------------+-----------------------------------------------------------------------------------------------------------------+

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• Branch
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Issue(s)

Relates to #2726

[github-actions]

Test Results

    5 files  ±0    172 suites  ±0   33m 4s ⏱️ +13s
2 452 tests ±0  2 452 ✅ ±0  0 💤 ±0  0 ❌ ±0 
7 654 runs  ±0  7 654 ✅ ±0  0 💤 ±0  0 ❌ ±0 

Results for commit 4661764. ± Comparison against base commit 2f5a13f.

♻️ This comment has been updated with latest results.

[Copilot]

Pull request overview

This PR adds support for displaying aggregator capabilities in the aggregator discovery process. The AggregatorDiscoverer trait has been made generic to support returning either basic endpoints or endpoints with capabilities, and the CLI now displays capability information (aggregate signature type and signed entity types) when discovering aggregators.

Changes:

• Made AggregatorDiscoverer trait generic over return type to support both AggregatorEndpoint and AggregatorEndpointWithCapabilities
• Added AggregatorEndpointWithCapabilities model with capability information and conversion implementations
• Updated CLI aggregator discovery command to display capabilities in a table format

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
internal/mithril-aggregator-discovery/src/interface.rs	Made AggregatorDiscoverer trait generic with type parameter T
internal/mithril-aggregator-discovery/src/model.rs	Added AggregatorEndpointWithCapabilities struct and conversion implementations
internal/mithril-aggregator-discovery/src/capabilities_discoverer.rs	Updated to return AggregatorEndpointWithCapabilities and modified iterator logic
internal/mithril-aggregator-discovery/src/http_config_discoverer.rs	Updated trait implementation to specify AggregatorEndpoint type parameter
internal/mithril-aggregator-discovery/src/rand_discoverer.rs	Updated trait implementation to specify AggregatorEndpoint type parameter
internal/mithril-aggregator-discovery/src/test/double/discoverer.rs	Updated test double to specify AggregatorEndpoint type parameter
internal/mithril-aggregator-discovery/src/lib.rs	Exported AggregatorEndpointWithCapabilities
mithril-client/src/client.rs	Updated type annotations and made discover_aggregator return endpoints with capabilities
mithril-client-cli/src/commands/tools/aggregator_discovery.rs	Enhanced output table to display aggregate signature type and signed entity types

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[Copilot]

Pull request overview

Copilot reviewed 9 out of 9 changed files in this pull request and generated 4 comments.

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[Alenar]

LGTM with one caution (see first comment).

Overall I feel that this api is fragile, when reading this PR I see two main problems:

1. usage of async code inside sync code because it returns an Iterator (the main problem)
2. the addition of a generic to the AggregatorDiscoverer trait, making the api less easy to use

1. may be addressed by using futures::stream::TryStream, but there may be some hiccup when using it downstream as this means not using the standard iterator api anymore.
2. is more difficult to solve and would probably mean an extensive refactoring of the crate (maybe with returning concrete type instead of returning traits).

None of this is need immediate action, this code is okay as is.

[Alenar]

I think this is dangerous, like Copilot said if called outside of tokio this will panic, instead of implementing TryFrom I think it would be better to instead add a retrieve_capabilities_blocking to AggregatorEndpoint which would be specify to not call it outside of a tokio runtime to avoid panic.

This would still be brittle as this don't change the fact that the capabilities discoverer have to run async code in a non-async method, but would be a avoid a second level of abstraction which hide this fact.

Also it could be interesting to explore using Handle::try_current() to avoid the panic if run outside of a tokio runtime but instead raising an error.

[Alenar]

[Nitpick] you should be able to also write this conversion like this:

Suggested change

	let next_aggregator = aggregators.next().map(|endpoint| endpoint.into());
	let next_aggregator = aggregators.next().map(Into::into);