statement-store: New RPC result types

[AndreiEres]

Description

Internal submittion result type changed to keep more information, which should be useful for RPC clients.

Application-level errors moved from JSON-RPC transport errors into the result type for statement_submit RPC method to help clients distinguish between submission outcomes instead of parsing error strings.

Runtime API wasn't changed.

Integration

Breaking Change - statement_submit now returns StatementSubmitResult enum instead of ().

Review Notes

Submission outcomes now return as Ok(result) with status field. Only infrastructure failures (database errors, decode errors) remain as JSON-RPC errors.

NetworkPriority removed as we never used it, reputation changes adjusted.

[carlosala]

Wayyyy better than before, thank you for the effort! 😉

[carlosala]

LGTM! 🚀

[carlosala]

Probably the next step is to rethink the whole API, reducing the surface and providing clear endpoints 👍🏻

[AndreiEres]

I looked at all cases where we use SubmitResult (internal, not RPC types). I think we could be more user-friendly by showing what exactly happened and helping users decide how to fix the problem. Then we can adjust RPC types according to that.

Current SubmitResult

• New(NetworkPriority)
  • Successfully validated and stored
    • ISSUE: it has NetworkPriority but we never set anything except High
• Known
  • Statement already exists
• KnownExpired
  • Statement exists but expired, can't happen during submission over RPC
• SubmitResult::Ignored
  • Encoded size > MAX_STATEMENT_SIZE
  • Data size > validation.max_size
  • Priority ≤ existing channel message priority
  • Priority too low, can't evict enough messages (account limits)
  • Store full (exceeds max_total_size or max_total_statements)
• SubmitResult::Bad
  • No statement proof
  • Bad statement proof
• InternalError(Error)
  • Validation internal error
  • Database commit failed

Proposed SubmitResult

enum SubmitResult {
	New,                       // Submitted
	Known,                     // Already exists
	KnownExpired,              // Already exists but expired, never appears in RPC
	Invalid(InvalidReason),    // Statement is invalid
	Rejected(RejectionReason), // Statement rejected, try again with different parameters
	InternalError(Error),      // Internal error
}

enum InvalidReason {
	NoProof,
	BadProof,
	EncodingTooLarge { submitted_size: usize, max_size: usize },
}

enum RejectionReason {
	DataTooLarge { submitted_size: usize, available_size: usize },
	ChannelPriorityTooLow { submitted_priority: u32, min_priority: u32 },
	AccountFull { submitted_priority: u32, min_priority: u32 },
	StoreFull { submitted_priority: u32, min_priority: u32 },
}

[AndreiEres]

/cmd prdoc --audience node_dev --bump major

[paritytech-workflow-stopper]

All GitHub workflows were cancelled due to failure one of the required jobs.
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