feat(index-node): add blockForPoi query for dispute investigation

Adds a new index-node GraphQL query that searches a block range to find
which block produced a given POI. This supports dispute investigation
where an indexer may have submitted a POI for block N that actually
corresponds to block X < N.

The resolver fetches all poi2$ digest entries in a single DB call, batch
fetches block hashes in 50k chunks, and runs ProofOfIndexingFinisher for
each block until a match is found.

Also adds network_for_deployment to the StatusStore trait and its
implementation chain (SubgraphStore, Store) as a supporting method
for resolving the chain store from a deployment hash.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: MoonBoi9001

Cargo.lock

@@ -10,6 +10,7 @@ use crate::blockchain::{BlockTime, ChainIdentifier, ExtendedBlockPtr};
 use crate::components::metrics::stopwatch::StopwatchMetrics;
 use crate::components::network_provider::ChainName;
 use crate::components::server::index_node::VersionInfo;
+use crate::components::subgraph::ProofOfIndexingVersion;
 use crate::components::subgraph::SubgraphVersionSwitchingMode;
 use crate::components::transaction_receipt;
 use crate::components::versions::ApiVersion;
@@ -741,6 +742,28 @@ pub trait QueryStore: Send + Sync {
     fn deployment_id(&self) -> DeploymentId;
 }
 
+/// A single POI digest entry from the `poi2$` table, representing the
+/// accumulated digest for a causality region over a block range.
+#[derive(Clone, Debug)]
+pub struct PoiDigestEntry {
+    /// The causality region identifier (the entity id in poi2$)
+    pub id: Id,
+    /// The accumulated digest bytes
+    pub digest: Vec<u8>,
+    /// Start of the block range (inclusive)
+    pub start_block: BlockNumber,
+    /// End of the block range (exclusive, i32::MAX if open-ended)
+    pub end_block: BlockNumber,
+}
+
+/// The full POI digest history for a deployment, containing all digest
+/// entries and the POI version needed to compute proofs.
+#[derive(Clone, Debug)]
+pub struct PoiDigestHistory {
+    pub entries: Vec<PoiDigestEntry>,
+    pub poi_version: ProofOfIndexingVersion,
+}
+
 /// A view of the store that can provide information about the indexing status
 /// of any subgraph and any deployment
 #[async_trait]
@@ -790,6 +813,19 @@ pub trait StatusStore: Send + Sync + 'static {
         block_number: BlockNumber,
         fetch_block_ptr: &dyn BlockPtrForNumber,
     ) -> Result<Option<(PartialBlockPtr, [u8; 32])>, StoreError>;
+
+    /// Retrieve the full POI digest history for a deployment within a block
+    /// range. Returns all `poi2$` entries whose block ranges overlap the
+    /// given range, along with the deployment's `ProofOfIndexingVersion`.
+    /// Returns `None` if the deployment doesn't exist or has no POI data.
+    async fn get_poi_digest_history(
+        &self,
+        subgraph_id: &DeploymentHash,
+        block_range: std::ops::Range<BlockNumber>,
+    ) -> Result<Option<PoiDigestHistory>, StoreError>;
+
+    /// Get the network for a deployment
+    async fn network_for_deployment(&self, id: &DeploymentHash) -> Result<String, StoreError>;
 }
 
 #[async_trait]

graph/src/components/store/traits.rs

@@ -11,3 +11,4 @@ graph-graphql = { path = "../../graphql" }
 graph-chain-ethereum = { path = "../../chain/ethereum" }
 graph-chain-near = { path = "../../chain/near" }
 git-testament = "0.2.6"
+rayon = "1"

server/index-node/Cargo.toml

@@ -1,6 +1,7 @@
-use std::collections::BTreeMap;
+use std::collections::{BTreeMap, HashMap};
 
 use async_trait::async_trait;
+use graph::components::subgraph::ProofOfIndexingFinisher;
 use graph::data::query::Trace;
 use graph::data::store::Id;
 use graph::prelude::alloy::primitives::Address;
@@ -454,6 +455,235 @@ where
         Ok(r::Value::List(public_poi_results))
     }
 
+    async fn resolve_block_for_poi(
+        &self,
+        field: &a::Field,
+    ) -> Result<r::Value, QueryExecutionError> {
+        const CHUNK_SIZE: i32 = 1_000_000;
+
+        let deployment_id = field
+            .get_required::<DeploymentHash>("subgraph")
+            .expect("Valid subgraph required");
+        let target_poi_hash = field
+            .get_required::<BlockHash>("targetPoi")
+            .expect("Valid targetPoi required");
+        let start_block = field
+            .get_required::<BlockNumber>("startBlock")
+            .expect("Valid startBlock required");
+        let end_block = field
+            .get_required::<BlockNumber>("endBlock")
+            .expect("Valid endBlock required");
+
+        let indexer = field
+            .get_optional::<Address>("indexer")
+            .expect("Invalid indexer");
+
+        if end_block <= start_block {
+            return Ok(r::Value::Null);
+        }
+
+        let target_bytes: [u8; 32] = match target_poi_hash.as_slice().try_into() {
+            Ok(bytes) => bytes,
+            Err(_) => {
+                error!(
+                    self.logger,
+                    "Invalid targetPoi: expected 32 bytes";
+                    "got_bytes" => target_poi_hash.as_slice().len()
+                );
+                return Ok(r::Value::Null);
+            }
+        };
+
+        // Resolve the network for this deployment
+        let network = match self.store.network_for_deployment(&deployment_id).await {
+            Ok(n) => n,
+            Err(e) => {
+                error!(
+                    self.logger,
+                    "Failed to resolve network for deployment";
+                    "subgraph" => &deployment_id,
+                    "error" => format!("{:?}", e)
+                );
+                return Ok(r::Value::Null);
+            }
+        };
+
+        // Fetch the full digest history for the block range
+        let history = match self
+            .store
+            .get_poi_digest_history(&deployment_id, start_block..end_block)
+            .await
+        {
+            Ok(Some(h)) => h,
+            Ok(None) => return Ok(r::Value::Null),
+            Err(e) => {
+                error!(
+                    self.logger,
+                    "Failed to fetch POI digest history";
+                    "subgraph" => &deployment_id,
+                    "error" => format!("{:?}", e)
+                );
+                return Ok(r::Value::Null);
+            }
+        };
+
+        let poi_version = history.poi_version;
+
+        // Build a lookup structure: for each causality region id, a sorted
+        // vec of (start_block, end_block, digest) for binary search.
+        let mut region_entries: HashMap<Id, Vec<(BlockNumber, BlockNumber, Vec<u8>)>> =
+            HashMap::new();
+        for entry in history.entries {
+            region_entries.entry(entry.id).or_default().push((
+                entry.start_block,
+                entry.end_block,
+                entry.digest,
+            ));
+        }
+        for entries in region_entries.values_mut() {
+            entries.sort_by_key(|(start, _, _)| *start);
+        }
+
+        // Share across rayon threads
+        let region_entries = Arc::new(region_entries);
+
+        let chain_store = match self.store.block_store().chain_store(&network).await {
+            Some(cs) => cs,
+            None => {
+                error!(
+                    self.logger,
+                    "Chain store not found for network";
+                    "network" => &network
+                );
+                return Ok(r::Value::Null);
+            }
+        };
+
+        // Search backwards from end_block (the match is likely near the top).
+        // Pipeline: fetch the next chunk while computing POIs for the current one.
+        let mut chunk_end = end_block;
+        let chunk_start = std::cmp::max(chunk_end - CHUNK_SIZE, start_block);
+
+        // Fetch first chunk
+        let block_numbers: Vec<BlockNumber> = (chunk_start..chunk_end).collect();
+        let mut current_ptrs = match chain_store
+            .cheap_clone()
+            .block_ptrs_by_numbers(block_numbers)
+            .await
+        {
+            Ok(ptrs) => ptrs,
+            Err(e) => {
+                error!(
+                    self.logger,
+                    "Failed to fetch block hashes";
+                    "range" => format!("{}..{}", chunk_start, chunk_end),
+                    "error" => format!("{:?}", e)
+                );
+                return Ok(r::Value::Null);
+            }
+        };
+        chunk_end = chunk_start;
+
+        loop {
+            // Start prefetching the next chunk while we process the current one
+            let next_chunk_end = chunk_end;
+            let next_chunk_start = std::cmp::max(next_chunk_end - CHUNK_SIZE, start_block);
+            let prefetch = if next_chunk_start < next_chunk_end {
+                let cs = chain_store.cheap_clone();
+                let numbers: Vec<BlockNumber> = (next_chunk_start..next_chunk_end).collect();
+                Some(tokio::spawn(async move {
+                    cs.block_ptrs_by_numbers(numbers).await
+                }))
+            } else {
+                None
+            };
+
+            // Collect blocks with unambiguous hashes for parallel search
+            let blocks_to_check: Vec<(BlockNumber, BlockHash)> = current_ptrs
+                .iter()
+                .filter_map(|(num, ptrs)| {
+                    if ptrs.len() == 1 {
+                        Some((*num, ptrs[0].hash.clone()))
+                    } else {
+                        None
+                    }
+                })
+                .collect();
+
+            // Parallel POI computation across all cores via rayon
+            let re = region_entries.clone();
+            let did = deployment_id.clone();
+            let result = graph::spawn_blocking_allow_panic(move || {
+                use rayon::prelude::*;
+                blocks_to_check
+                    .par_iter()
+                    .find_map_any(|(block_num, block_hash)| {
+                        let block_ptr = BlockPtr::new(block_hash.clone(), *block_num);
+                        let mut finisher =
+                            ProofOfIndexingFinisher::new(&block_ptr, &did, &indexer, poi_version);
+
+                        for (region_id, entries) in re.as_ref() {
+                            let idx = entries.partition_point(|(start, _, _)| *start <= *block_num);
+                            if idx == 0 {
+                                continue;
+                            }
+                            let (start, end, ref digest) = entries[idx - 1];
+                            if *block_num >= start && *block_num < end {
+                                finisher.add_causality_region(region_id, digest);
+                            }
+                        }
+
+                        let computed = finisher.finish();
+                        if computed == target_bytes {
+                            Some((*block_num, block_hash.clone(), computed))
+                        } else {
+                            None
+                        }
+                    })
+            })
+            .await
+            .map_err(|e| QueryExecutionError::Panic(e.to_string()))?;
+
+            if let Some((block_num, block_hash, computed_poi)) = result {
+                // Found it - abort any in-flight prefetch
+                if let Some(handle) = prefetch {
+                    handle.abort();
+                }
+                return Ok(object! {
+                    __typename: "PoiSearchResult",
+                    deployment: deployment_id.to_string(),
+                    block: object! {
+                        hash: block_hash.hash_hex(),
+                        number: block_num,
+                    },
+                    proofOfIndexing: format!("0x{}", hex::encode(computed_poi)),
+                });
+            }
+
+            // Move to the next chunk
+            match prefetch {
+                Some(handle) => {
+                    current_ptrs = handle
+                        .await
+                        .map_err(|e| QueryExecutionError::Panic(e.to_string()))?
+                        .map_err(|e| {
+                            error!(
+                                self.logger,
+                                "Failed to fetch block hashes";
+                                "range" => format!("{}..{}", next_chunk_start, next_chunk_end),
+                                "error" => format!("{:?}", e)
+                            );
+                            QueryExecutionError::StoreError(e.into())
+                        })?;
+                    chunk_end = next_chunk_start;
+                }
+                None => break,
+            }
+        }
+
+        Ok(r::Value::Null)
+    }
+
     async fn resolve_indexing_status_for_version(
         &self,
         field: &a::Field,
@@ -858,6 +1088,7 @@ where
             // The top-level `subgraphVersions` field
             (None, "apiVersions") => self.resolve_api_versions(field),
             (None, "version") => self.version(),
+            (None, "blockForPoi") => self.resolve_block_for_poi(field).await,
 
             // Resolve fields of `Object` values (e.g. the `latestBlock` field of `EthereumBlock`)
             (value, _) => Ok(value.unwrap_or(r::Value::Null)),

server/index-node/src/resolver.rs

@@ -46,6 +46,18 @@ type Query {
     blockHash: Bytes!
   ): [CachedEthereumCall!]
   apiVersions(subgraphId: String!): [ApiVersion!]!
+  """
+  Find the block number that produced a given proof of indexing.
+  Used for dispute investigation to verify which block an indexer
+  actually synced to when they submitted a POI.
+  """
+  blockForPoi(
+    subgraph: String!
+    targetPoi: Bytes!
+    startBlock: Int!
+    endBlock: Int!
+    indexer: Bytes
+  ): PoiSearchResult
 }
 
 type Version {
@@ -203,6 +215,12 @@ type ProofOfIndexingResult {
   proofOfIndexing: Bytes
 }
 
+type PoiSearchResult {
+  block: Block!
+  deployment: String!
+  proofOfIndexing: Bytes!
+}
+
 type ApiVersion {
   """
   Version number in SemVer format