services/horizon/internal/integration: Add load test which generates ledgers loaded with soroban Tx Meta

[tamirms]

PR Checklist

PR Structure

• This PR has reasonably narrow scope (if not, break it down into smaller PRs).
• This PR avoids mixing refactoring changes with feature changes (split into two PRs
  otherwise).
• This PR's title starts with name of package that is most changed in the PR, ex.
  services/friendbot, or all or doc if the changes are broad or impact many
  packages.

Thoroughness

• This PR adds tests for the most critical parts of the new functionality or fixes.
• I've updated any docs (developer docs, .md
  files, etc... affected by this change). Take a look in the docs folder for a given service,
  like this one.

Release planning

• I've reviewed the changes in this PR and if I consider them worthwhile for being mentioned on release notes then I have updated the relevant CHANGELOG.md within the component folder structure. For example, if I changed horizon, then I updated (services/horizon/CHANGELOG.md. I add a new line item describing the change and reference to this PR. If I don't update a CHANGELOG, I acknowledge this PR's change may not be mentioned in future release notes.
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  semver, or if it's mainly a patch change. The PR is targeted at the next
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What

Close stellar/stellar-rpc#330

This PR implements an integration load test to generate ledgers with soroban transactions. The test can be configured using the following parameters:

• transactions-per-ledger number of transactions per ledger
• transfers-per-tx number of asset transfers for each transaction
• ledgers number of ledgers to generate

The test will output ledgers number of ledgers each containing transactions-per-ledger transactions. Each transaction will have transfers-per-tx asset transfers. Half the asset transfers will result in movement among accounts and the other half of the transfers will result in movement between accounts and contracts.

The test is implemented as follows:

1. We use clients/stellarcore: Support more parameters from the upgrades endpoint #5546 to setup a private stellar network with unlimited soroban TPS.
2. We use a bulk transfer soroban contract which will allow us to have a single invocation which transfers assets to multiple destination accounts / contracts
3. We submit many soroban transactions to core
4. We merge ledgers together until we until we have sufficient data to populate the ledger data which satisfies the configuration parameters.

The transactions are carefully designed to make the merging operation safe. In particular, we ensure that the source / fee account of each transaction is not used or modified more than once within the batch of ledgers which will be merged.

Why

Currently, the number of soroban transactions per ledger is limited but in the future we plan to raise that limit. But before doing so, we would like to use this tool to generate ledgers with a high volume of soroban activity so we can test the limits of horizon and rpc ingestion.

#5482

Known limitations

[N/A]

[2opremio]

Really cool. I wonder, though, if this could be factored out in some way so that it can be reused in Stellar-RPC tests. Or is the idea to simply compile the test and pass parameters to it? that isn't very flexible though.

[tamirms]

I wonder, though, if this could be factored out in some way so that it can be reused in Stellar-RPC tests.

yeah, ideally this could be executed outside the context of a Go test. But, there is a lot of code in the integration testing framework we have which makes it easy to spin up and tear down the stand alone stellar network. It would require much more effort to decouple that framework code from testing.T.

Or is the idea to simply compile the test and pass parameters to it? that isn't very flexible though.

My intention was to use this test to generate a bunch of ledgers. Once we have the file with the generated ledgers we can replay them to rpc / horizon. The generated ledgers file is the only artifact we need to load test ingestion in horizon / rpc