cmd/loop: fix route hint array parsing - #1213
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Treat --route_hints as a single JSON array instead of a repeatable string slice. This preserves commas in the JSON without disabling slice separators for unrelated UTXO and deposit flags. Decode the outer array into raw JSON elements, then use protojson for each RouteHint protobuf. This follows protobuf JSON field naming and quoted uint64 semantics, and rejects unknown fields instead of silently accepting misspelled hints. Reject empty RouteHint messages at the RPC boundary. An empty route would be encoded as an empty BOLT 11 r field, which zpay32 rejects when decoding the invoice. Add recorded CLI sessions covering valid single, multiple, and multi-hop hints, malformed input, RPC-boundary validation, and comma-separated UTXO and deposit selections.
The protobuf implementation intentionally varies the separator after its error prefix between an ASCII space and a non-breaking space across builds. This made recorded route hint sessions depend on the test binary and fail CI despite identical parsing behavior. Normalize the non-breaking space before returning the CLI error so the user-facing message and recorded sessions remain stable across builds.
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LGTM, pending one finding.
| if rpcHint.ChanId == 0 { | ||
| return zpay32.HopHint{}, fmt.Errorf("channel ID is zero") | ||
| } | ||
| if rpcHint.CltvExpiryDelta == 0 { |
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Zero CLTV deltas are protocol-permitted. The new check in swapclient_server.go rejects every hint with cltv_expiry_delta == 0. BOLT 7 defines this as an unrestricted u16 and only requires it to equal the blocks subtracted; BOLT 11 carries that value into route hints without adding a nonzero constraint. This can reject a standards-permitted private-channel policy and breaks previously accepted gRPC requests. Keep the > MaxUint16 guard, but remove the zero check unless Loop intentionally documents a stricter API requirement. BOLT 7, BOLT 11.
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Another approach for #1209. We can have only a single
--route_hintswith complete JSON, so the type should becli.StringFlag. And then we don't needDisableSliceFlagSeparatorand touching other flags (--utxoand--deposit_outpoint).Treat
--route_hintsas a single JSON array instead of a repeatable string slice. This preserves commas in the JSON without disabling slice separators for unrelated UTXO and deposit flags.Decode the outer array into raw JSON elements, then use protojson for each
RouteHintprotobuf. This follows protobuf JSON field naming and quoted uint64 semantics, and rejects unknown fields instead of silently accepting misspelled hints.Reject empty RouteHint messages at the RPC boundary. An empty route would be encoded as an empty BOLT 11
rfield, which zpay32 rejects when decoding the invoice.Add recorded CLI sessions covering valid single, multiple, and multi-hop hints, malformed input, RPC-boundary validation, and comma-separated UTXO and deposit selections.
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docs/release-notes/release-notes-next.md, or apply theno-changeloglabel (required by CI)