EmptyNodeCapabilities for chains that don't discriminate nodes

chain/arweave/src/adapter.rs

@@ -1,4 +1,3 @@
-use crate::capabilities::NodeCapabilities;
 use crate::{data_source::DataSource, Chain};
 use graph::blockchain as bc;
 use graph::prelude::*;
@@ -26,8 +25,8 @@ impl bc::TriggerFilter<Chain> for TriggerFilter {
         transaction_filter.extend(ArweaveTransactionFilter::from_data_sources(data_sources));
     }
 
-    fn node_capabilities(&self) -> NodeCapabilities {
-        NodeCapabilities {}
+    fn node_capabilities(&self) -> bc::EmptyNodeCapabilities<Chain> {
+        bc::EmptyNodeCapabilities::default()
     }
 
     fn extend_with_template(

chain/arweave/src/chain.rs

@@ -1,4 +1,4 @@
-use graph::blockchain::{Block, BlockchainKind};
+use graph::blockchain::{Block, BlockchainKind, EmptyNodeCapabilities};
 use graph::cheap_clone::CheapClone;
 use graph::data::subgraph::UnifiedMappingApiVersion;
 use graph::firehose::{FirehoseEndpoint, FirehoseEndpoints};
@@ -20,7 +20,6 @@ use prost::Message;
 use std::sync::Arc;
 
 use crate::adapter::TriggerFilter;
-use crate::capabilities::NodeCapabilities;
 use crate::data_source::{DataSourceTemplate, UnresolvedDataSourceTemplate};
 use crate::runtime::RuntimeAdapter;
 use crate::trigger::{self, ArweaveTrigger};
@@ -82,7 +81,7 @@ impl Blockchain for Chain {
 
     type TriggerFilter = crate::adapter::TriggerFilter;
 
-    type NodeCapabilities = crate::capabilities::NodeCapabilities;
+    type NodeCapabilities = EmptyNodeCapabilities<Self>;
 
     fn triggers_adapter(
         &self,
@@ -116,7 +115,11 @@ impl Blockchain for Chain {
         unified_api_version: UnifiedMappingApiVersion,
     ) -> Result<Box<dyn BlockStream<Self>>, Error> {
         let adapter = self
-            .triggers_adapter(&deployment, &NodeCapabilities {}, unified_api_version)
+            .triggers_adapter(
+                &deployment,
+                &EmptyNodeCapabilities::default(),
+                unified_api_version,
+            )
             .unwrap_or_else(|_| panic!("no adapter for network {}", self.name));
 
         let firehose_endpoint = self.firehose_endpoints.random()?;

chain/arweave/src/lib.rs

@@ -1,5 +1,4 @@
 mod adapter;
-mod capabilities;
 mod chain;
 mod codec;
 mod data_source;

chain/cosmos/src/adapter.rs

@@ -3,7 +3,6 @@ use std::collections::HashSet;
 use prost::Message;
 use prost_types::Any;
 
-use crate::capabilities::NodeCapabilities;
 use crate::{data_source::DataSource, Chain};
 use graph::blockchain as bc;
 use graph::firehose::EventTypeFilter;
@@ -25,8 +24,8 @@ impl bc::TriggerFilter<Chain> for TriggerFilter {
         self.block_filter.extend_from_data_sources(data_sources);
     }
 
-    fn node_capabilities(&self) -> NodeCapabilities {
-        NodeCapabilities {}
+    fn node_capabilities(&self) -> bc::EmptyNodeCapabilities<Chain> {
+        bc::EmptyNodeCapabilities::default()
     }
 
     fn extend_with_template(

chain/cosmos/src/chain.rs

@@ -11,16 +11,15 @@ use graph::{
             FirehoseMapper as FirehoseMapperTrait, TriggersAdapter as TriggersAdapterTrait,
         },
         firehose_block_stream::FirehoseBlockStream,
-        Block as _, BlockHash, BlockPtr, Blockchain, BlockchainKind, IngestorError,
-        RuntimeAdapter as RuntimeAdapterTrait,
+        Block as _, BlockHash, BlockPtr, Blockchain, BlockchainKind, EmptyNodeCapabilities,
+        IngestorError, RuntimeAdapter as RuntimeAdapterTrait,
     },
     components::store::DeploymentLocator,
     firehose::{self, FirehoseEndpoint, FirehoseEndpoints, ForkStep},
     prelude::{async_trait, o, BlockNumber, ChainStore, Error, Logger, LoggerFactory},
 };
 use prost::Message;
 
-use crate::capabilities::NodeCapabilities;
 use crate::data_source::{
     DataSource, DataSourceTemplate, EventOrigin, UnresolvedDataSource, UnresolvedDataSourceTemplate,
 };
@@ -80,7 +79,7 @@ impl Blockchain for Chain {
 
     type TriggerFilter = TriggerFilter;
 
-    type NodeCapabilities = NodeCapabilities;
+    type NodeCapabilities = EmptyNodeCapabilities<Self>;
 
     fn is_refetch_block_required(&self) -> bool {
         false
@@ -113,7 +112,11 @@ impl Blockchain for Chain {
         unified_api_version: UnifiedMappingApiVersion,
     ) -> Result<Box<dyn BlockStream<Self>>, Error> {
         let adapter = self
-            .triggers_adapter(&deployment, &NodeCapabilities {}, unified_api_version)
+            .triggers_adapter(
+                &deployment,
+                &EmptyNodeCapabilities::default(),
+                unified_api_version,
+            )
             .unwrap_or_else(|_| panic!("no adapter for network {}", self.name));
 
         let firehose_endpoint = self.firehose_endpoints.random()?;

chain/cosmos/src/lib.rs

@@ -1,5 +1,4 @@
 mod adapter;
-mod capabilities;
 pub mod chain;
 pub mod codec;
 mod data_source;

chain/ethereum/src/capabilities.rs

@@ -1,11 +1,9 @@
 use anyhow::Error;
 use graph::impl_slog_value;
+use std::cmp::Ordering;
+use std::collections::BTreeSet;
 use std::fmt;
 use std::str::FromStr;
-use std::{
-    cmp::{Ord, Ordering, PartialOrd},
-    collections::BTreeSet,
-};
 
 use crate::DataSource;
 
@@ -15,28 +13,28 @@ pub struct NodeCapabilities {
     pub traces: bool,
 }
 
-// Take all NodeCapabilities fields into account when ordering
-// A NodeCapabilities instance is considered equal or greater than another
-// if all of its fields are equal or greater than the other
-impl Ord for NodeCapabilities {
-    fn cmp(&self, other: &Self) -> Ordering {
-        match (
+/// Two [`NodeCapabilities`] can only be compared if one is the subset of the
+/// other. No [`Ord`] (i.e. total order) implementation is applicable.
+impl PartialOrd for NodeCapabilities {
+    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
+        product_order([
             self.archive.cmp(&other.archive),
             self.traces.cmp(&other.traces),
-        ) {
-            (Ordering::Greater, Ordering::Greater) => Ordering::Greater,
-            (Ordering::Greater, Ordering::Equal) => Ordering::Greater,
-            (Ordering::Equal, Ordering::Greater) => Ordering::Greater,
-            (Ordering::Equal, Ordering::Equal) => Ordering::Equal,
-            (Ordering::Less, _) => Ordering::Less,
-            (_, Ordering::Less) => Ordering::Less,
-        }
+        ])
     }
 }
 
-impl PartialOrd for NodeCapabilities {
-    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
-        Some(self.cmp(other))
+/// Defines a [product order](https://en.wikipedia.org/wiki/Product_order) over
+/// an array of [`Ordering`].
+fn product_order<const N: usize>(cmps: [Ordering; N]) -> Option<Ordering> {
+    if cmps.iter().all(|c| c.is_eq()) {
+        Some(Ordering::Equal)
+    } else if cmps.iter().all(|c| c.is_le()) {
+        Some(Ordering::Less)
+    } else if cmps.iter().all(|c| c.is_ge()) {
+        Some(Ordering::Greater)
+    } else {
+        None
     }
 }
 

chain/ethereum/src/network.rs

@@ -1,6 +1,7 @@
 use anyhow::{anyhow, Context};
 use graph::cheap_clone::CheapClone;
 use graph::prelude::rand::{self, seq::IteratorRandom};
+use std::cmp::Ordering;
 use std::collections::HashMap;
 use std::sync::Arc;
 
@@ -134,9 +135,14 @@ impl EthereumNetworks {
 
     pub fn sort(&mut self) {
         for adapters in self.networks.values_mut() {
-            adapters
-                .adapters
-                .sort_by_key(|adapter| adapter.capabilities)
+            adapters.adapters.sort_by(|a, b| {
+                a.capabilities
+                    .partial_cmp(&b.capabilities)
+                    // We can't define a total ordering over node capabilities,
+                    // so incomparable items are considered equal and end up
+                    // near each other.
+                    .unwrap_or(Ordering::Equal)
+            })
         }
     }
 

chain/near/src/adapter.rs

@@ -1,6 +1,5 @@
 use std::collections::HashSet;
 
-use crate::capabilities::NodeCapabilities;
 use crate::data_source::PartialAccounts;
 use crate::{data_source::DataSource, Chain};
 use graph::blockchain as bc;
@@ -29,8 +28,8 @@ impl bc::TriggerFilter<Chain> for TriggerFilter {
         receipt_filter.extend(NearReceiptFilter::from_data_sources(data_sources));
     }
 
-    fn node_capabilities(&self) -> NodeCapabilities {
-        NodeCapabilities {}
+    fn node_capabilities(&self) -> bc::EmptyNodeCapabilities<Chain> {
+        bc::EmptyNodeCapabilities::default()
     }
 
     fn extend_with_template(

chain/near/src/chain.rs

@@ -11,7 +11,8 @@ use graph::{
             FirehoseMapper as FirehoseMapperTrait, TriggersAdapter as TriggersAdapterTrait,
         },
         firehose_block_stream::FirehoseBlockStream,
-        BlockHash, BlockPtr, Blockchain, IngestorError, RuntimeAdapter as RuntimeAdapterTrait,
+        BlockHash, BlockPtr, Blockchain, EmptyNodeCapabilities, IngestorError,
+        RuntimeAdapter as RuntimeAdapterTrait,
     },
     components::store::DeploymentLocator,
     firehose::{self as firehose, ForkStep},
@@ -21,7 +22,6 @@ use prost::Message;
 use std::sync::Arc;
 
 use crate::adapter::TriggerFilter;
-use crate::capabilities::NodeCapabilities;
 use crate::data_source::{DataSourceTemplate, UnresolvedDataSourceTemplate};
 use crate::runtime::RuntimeAdapter;
 use crate::trigger::{self, NearTrigger};
@@ -46,7 +46,11 @@ impl BlockStreamBuilder<Chain> for NearStreamBuilder {
         unified_api_version: UnifiedMappingApiVersion,
     ) -> Result<Box<dyn BlockStream<Chain>>> {
         let adapter = chain
-            .triggers_adapter(&deployment, &NodeCapabilities {}, unified_api_version)
+            .triggers_adapter(
+                &deployment,
+                &EmptyNodeCapabilities::default(),
+                unified_api_version,
+            )
             .unwrap_or_else(|_| panic!("no adapter for network {}", chain.name));
 
         let firehose_endpoint = chain.firehose_endpoints.random()?;
@@ -140,7 +144,7 @@ impl Blockchain for Chain {
 
     type TriggerFilter = crate::adapter::TriggerFilter;
 
-    type NodeCapabilities = crate::capabilities::NodeCapabilities;
+    type NodeCapabilities = EmptyNodeCapabilities<Chain>;
 
     fn triggers_adapter(
         &self,

chain/near/src/lib.rs

@@ -1,5 +1,4 @@
 mod adapter;
-mod capabilities;
 mod chain;
 pub mod codec;
 mod data_source;