starknet_os_runner: simulate tx and get rpc initial reads

[AvivYossef-starkware]

Note

Low Risk
Mostly additive changes: a new RPC helper + JSON deserialization plus tests and a recorded fixture. Risk is low, mainly around compatibility with v0.10 nodes and correctness of the initial_reads parsing.

Overview
Adds an RPC path to prefetch initial state reads by calling starknet_simulateTransactions with the RETURN_INITIAL_READS flag and converting the response into blockifier StateMaps.

Introduces a small serde_utils module to deserialize pathfinder v0.10 initial_reads JSON, plus unit/integration coverage and a new rpc_records fixture to allow offline replay of the simulate response.

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[reviewable-StarkWare]

This change is 

[AvivYossef-starkware]

• starknet_os_runner: wire prefatched state reader #12872
• starknet_os_runner: add SimulatedStateReader with StateReader and FetchCompiledClasses impls #12870
• starknet_os_runner: simulate tx and get rpc initial reads #12869 👈 (View in Graphite)
• starknet_os_runner: add RpcVirtualBlockExecutorConfig with prefetch_state #12851 : 1 other dependent PR (#12910 )
• main-v0.14.2

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[meship-starkware]

@meship-starkware reviewed 5 files and all commit messages, and made 2 comments.
Reviewable status: 5 of 6 files reviewed, 2 unresolved discussions (waiting on AvivYossef-starkware, einat-starkware, and noaov1).

---

crates/starknet_os_runner/src/running/serde_utils_test.rs line 31 at r1 (raw file):

    #[case] expected_nonces: usize,
    #[case] expected_class_hashes: usize,
    #[case] expected_declared_contracts: usize,

Does it represent the length of the list? than maybe, because right now it looks like a flag. I also think it could be interesting if one of the fields contains more than one element in the first test case

Suggestion:

    #[case] expected_storage_len: usize,
    #[case] expected_nonces: usize,
    #[case] expected_class_hashes: usize,
    #[case] expected_declared_contracts: usize,

---

crates/starknet_os_runner/src/running/serde_utils_test.rs line 33 at r1 (raw file):

    #[case] expected_declared_contracts: usize,
) {
    let state_maps = deserialize_rpc_initial_reads(input).unwrap();

I think we should have the expected map and not just its length. I am not sure the length is enough

Code quote:

 let state_maps = deserialize_rpc_initial_reads(input).unwrap();

[meship-starkware]

@meship-starkware reviewed 1 file and made 1 comment.
Reviewable status: all files reviewed, 3 unresolved discussions (waiting on AvivYossef-starkware, einat-starkware, and noaov1).

---

crates/starknet_os_runner/src/running/virtual_block_executor_test.rs line 172 at r1 (raw file):

/// ```
#[tokio::test(flavor = "multi_thread")]
async fn test_simulate_and_get_initial_reads() {

Is the test not ignored on purpose?

Code quote:

#[tokio::test(flavor = "multi_thread")]
async fn test_simulate_and_get_initial_reads() {

[AvivYossef-starkware]

@AvivYossef-starkware made 3 comments.
Reviewable status: 5 of 6 files reviewed, 3 unresolved discussions (waiting on einat-starkware, meship-starkware, and noaov1).

---

crates/starknet_os_runner/src/running/serde_utils_test.rs line 31 at r1 (raw file):

Previously, meship-starkware (Meshi Peled) wrote…

Does it represent the length of the list? than maybe, because right now it looks like a flag. I also think it could be interesting if one of the fields contains more than one element in the first test case

thanks

---

crates/starknet_os_runner/src/running/serde_utils_test.rs line 33 at r1 (raw file):

Previously, meship-starkware (Meshi Peled) wrote…

I think we should have the expected map and not just its length. I am not sure the length is enough

Done.

---

crates/starknet_os_runner/src/running/virtual_block_executor_test.rs line 172 at r1 (raw file):

Previously, meship-starkware (Meshi Peled) wrote…

Is the test not ignored on purpose?

Yes , we use the records in the resources dir

[meship-starkware]

@meship-starkware reviewed 1 file and all commit messages, made 1 comment, and resolved 3 discussions.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on AvivYossef-starkware, einat-starkware, and noaov1).

---

crates/starknet_os_runner/src/running/virtual_block_executor_test.rs line 169 at r1 (raw file):

///
/// # Offline (after recording):
/// cargo test -p starknet_os_runner test_simulate_and_get_initial_reads -- --ignored

Please fix or -- --include_ignore otherwise the test wont run

Suggestion:

/// RECORD_RPC_RECORDS=1 NODE_URL=http://<privacy-env-node>/rpc/v0_10 \
///     cargo test -p starknet_os_runner test_simulate_and_get_initial_reads
///
/// # Offline (after recording):
/// cargo test -p starknet_os_runner test_simulate_and_get_initial_reads 

[meship-starkware]

@meship-starkware reviewed 1 file and all commit messages.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on AvivYossef-starkware, einat-starkware, and noaov1).

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[graphite-app]

Merge activity

• Mar 1, 4:26 PM UTC: Graphite rebased this pull request, because this pull request is set to merge when ready.

[AvivYossef-starkware]

@AvivYossef-starkware reviewed 3 files and all commit messages, and resolved 1 discussion.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on einat-starkware and noaov1).