graphql: Spawn ws connections as non-blocking

Author: leoyvens

graph/src/data/query/error.rs

@@ -57,6 +57,8 @@ pub enum QueryExecutionError {
     UndefinedFragment(String),
     // Using slow and prefetch query resolution yield different results
     IncorrectPrefetchResult { slow: q::Value, prefetch: q::Value },
+    Panic(String),
+    EventStreamError,
 }
 
 impl Error for QueryExecutionError {
@@ -200,7 +202,9 @@ impl fmt::Display for QueryExecutionError {
             IncorrectPrefetchResult{ .. } => write!(f, "Running query with prefetch \
                            and slow query resolution yielded different results. \
                            This is a bug. Please open an issue at \
-                           https://github.com/graphprotocol/graph-node")
+                           https://github.com/graphprotocol/graph-node"),
+            Panic(msg) => write!(f, "panic processing query: {}", msg),
+            EventStreamError => write!(f, "error in the subscription event stream")
         }
     }
 }

graph/src/data/subscription/result.rs

@@ -1,9 +1,8 @@
-use futures::prelude::*;
-
 use crate::prelude::QueryResult;
+use std::marker::Unpin;
 
 /// A stream of query results for a subscription.
-pub type QueryResultStream = Box<dyn Stream<Item = QueryResult, Error = ()> + Send>;
+pub type QueryResultStream = Box<dyn futures03::stream::Stream<Item = QueryResult> + Send + Unpin>;
 
 /// The result of running a subscription, if successful.
 pub type SubscriptionResult = QueryResultStream;

graph/src/lib.rs

@@ -21,7 +21,9 @@ pub mod mock {
 
 /// Wrapper for spawning tasks that abort on panic, which is our default.
 mod task_spawn;
-pub use task_spawn::{block_on_allow_panic, spawn, spawn_blocking, spawn_blocking_allow_panic};
+pub use task_spawn::{
+    block_on_allow_panic, spawn, spawn_allow_panic, spawn_blocking, spawn_blocking_allow_panic,
+};
 
 /// A prelude that makes all system component traits and data types available.
 ///

graph/src/task_spawn.rs

@@ -19,6 +19,12 @@ pub fn spawn<T: Send + 'static>(f: impl Future03<Output = T> + Send + 'static) -
     tokio::spawn(abort_on_panic(f))
 }
 
+pub fn spawn_allow_panic<T: Send + 'static>(
+    f: impl Future03<Output = T> + Send + 'static,
+) -> JoinHandle<T> {
+    tokio::spawn(f)
+}
+
 /// Aborts on panic.
 pub fn spawn_blocking<T: Send + 'static>(
     f: impl Future03<Output = T> + Send + 'static,

graphql/src/execution/execution.rs

@@ -29,7 +29,7 @@ pub enum ExecutionMode {
 
 /// Contextual information passed around during query execution.
 #[derive(Clone)]
-pub struct ExecutionContext<'a, R>
+pub struct ExecutionContext<R>
 where
     R: Resolver,
 {
@@ -40,13 +40,13 @@ where
     pub schema: Arc<Schema>,
 
     /// The query to execute.
-    pub document: &'a q::Document,
+    pub document: q::Document,
 
     /// The resolver to use.
     pub resolver: Arc<R>,
 
     /// The current field stack (e.g. allUsers > friends > name).
-    pub fields: Vec<&'a q::Field>,
+    pub fields: Vec<q::Field>,
 
     /// Variable values.
     pub variable_values: Arc<HashMap<q::Name, q::Value>>,
@@ -89,18 +89,18 @@ fn get_field<'a>(object_type: impl Into<ObjectOrInterface<'a>>, name: &Name) ->
     }
 }
 
-impl<'a, R> ExecutionContext<'a, R>
+impl<R> ExecutionContext<R>
 where
     R: Resolver,
 {
     /// Creates a derived context for a new field (added to the top of the field stack).
-    pub fn for_field(
+    pub fn for_field<'a>(
         &self,
-        field: &'a q::Field,
+        field: &q::Field,
         object_type: impl Into<ObjectOrInterface<'a>>,
     ) -> Result<Self, QueryExecutionError> {
         let mut ctx = self.clone();
-        ctx.fields.push(field);
+        ctx.fields.push(field.clone());
         if let Some(bc) = field.block_constraint(object_type)? {
             ctx.block = self.resolver.locate_block(&bc)?;
         }
@@ -116,7 +116,7 @@ where
             logger: self.logger.clone(),
             resolver: Arc::new(introspection_resolver),
             schema: Arc::new(introspection_schema),
-            document: &self.document,
+            document: self.document.clone(),
             fields: vec![],
             variable_values: self.variable_values.clone(),
             deadline: self.deadline,
@@ -327,13 +327,10 @@ where
 }
 
 /// Executes the root selection set of a query.
-pub fn execute_root_selection_set<'a, R>(
-    ctx: &ExecutionContext<'a, R>,
-    selection_set: &'a q::SelectionSet,
-) -> Result<q::Value, Vec<QueryExecutionError>>
-where
-    R: Resolver,
-{
+pub fn execute_root_selection_set(
+    ctx: &ExecutionContext<impl Resolver>,
+    selection_set: &q::SelectionSet,
+) -> Result<q::Value, Vec<QueryExecutionError>> {
     // Obtain the root Query type and fail if there isn't one
     let query_type = match sast::get_root_query_type(&ctx.schema.document) {
         Some(t) => t,
@@ -405,15 +402,12 @@ where
 /// Executes a selection set, requiring the result to be of the given object type.
 ///
 /// Allows passing in a parent value during recursive processing of objects and their fields.
-pub fn execute_selection_set<'a, R>(
-    ctx: &ExecutionContext<'a, R>,
-    selection_set: &'a q::SelectionSet,
+pub fn execute_selection_set(
+    ctx: &ExecutionContext<impl Resolver>,
+    selection_set: &q::SelectionSet,
     object_type: &s::ObjectType,
     object_value: &Option<q::Value>,
-) -> Result<q::Value, Vec<QueryExecutionError>>
-where
-    R: Resolver,
-{
+) -> Result<q::Value, Vec<QueryExecutionError>> {
     Ok(q::Value::Object(execute_selection_set_to_map(
         ctx,
         selection_set,
@@ -422,15 +416,12 @@ where
     )?))
 }
 
-fn execute_selection_set_to_map<'a, R>(
-    ctx: &ExecutionContext<'a, R>,
-    selection_set: &'a q::SelectionSet,
+fn execute_selection_set_to_map(
+    ctx: &ExecutionContext<impl Resolver>,
+    selection_set: &q::SelectionSet,
     object_type: &s::ObjectType,
     object_value: &Option<q::Value>,
-) -> Result<BTreeMap<String, q::Value>, Vec<QueryExecutionError>>
-where
-    R: Resolver,
-{
+) -> Result<BTreeMap<String, q::Value>, Vec<QueryExecutionError>> {
     let mut errors: Vec<QueryExecutionError> = Vec::new();
     let mut result_map: BTreeMap<String, q::Value> = BTreeMap::new();
 
@@ -486,15 +477,12 @@ where
 }
 
 /// Collects fields of a selection set.
-pub fn collect_fields<'a, R>(
-    ctx: &ExecutionContext<'a, R>,
+pub fn collect_fields<'a>(
+    ctx: &'a ExecutionContext<impl Resolver>,
     object_type: &s::ObjectType,
     selection_set: &'a q::SelectionSet,
     visited_fragments: Option<HashSet<&'a q::Name>>,
-) -> IndexMap<&'a String, Vec<&'a q::Field>>
-where
-    R: Resolver,
-{
+) -> IndexMap<&'a String, Vec<&'a q::Field>> {
     let mut visited_fragments = visited_fragments.unwrap_or_default();
     let mut grouped_fields: IndexMap<_, Vec<_>> = IndexMap::new();
 
@@ -592,7 +580,7 @@ where
 
 /// Determines whether a fragment is applicable to the given object type.
 fn does_fragment_type_apply(
-    ctx: ExecutionContext<'_, impl Resolver>,
+    ctx: ExecutionContext<impl Resolver>,
     object_type: &s::ObjectType,
     fragment_type: &q::TypeCondition,
 ) -> bool {
@@ -622,17 +610,14 @@ fn does_fragment_type_apply(
 }
 
 /// Executes a field.
-fn execute_field<'a, R>(
-    ctx: &ExecutionContext<'a, R>,
+fn execute_field(
+    ctx: &ExecutionContext<impl Resolver>,
     object_type: &s::ObjectType,
     object_value: &Option<q::Value>,
-    field: &'a q::Field,
+    field: &q::Field,
     field_definition: &s::Field,
-    fields: Vec<&'a q::Field>,
-) -> Result<q::Value, Vec<QueryExecutionError>>
-where
-    R: Resolver,
-{
+    fields: Vec<&q::Field>,
+) -> Result<q::Value, Vec<QueryExecutionError>> {
     coerce_argument_values(ctx, object_type, field)
         .and_then(|argument_values| {
             resolve_field_value(
@@ -649,18 +634,15 @@ where
 }
 
 /// Resolves the value of a field.
-fn resolve_field_value<'a, R>(
-    ctx: &ExecutionContext<'a, R>,
+fn resolve_field_value(
+    ctx: &ExecutionContext<impl Resolver>,
     object_type: &s::ObjectType,
     object_value: &Option<q::Value>,
     field: &q::Field,
     field_definition: &s::Field,
     field_type: &s::Type,
     argument_values: &HashMap<&q::Name, q::Value>,
-) -> Result<q::Value, Vec<QueryExecutionError>>
-where
-    R: Resolver,
-{
+) -> Result<q::Value, Vec<QueryExecutionError>> {
     match field_type {
         s::Type::NonNullType(inner_type) => resolve_field_value(
             ctx,
@@ -695,18 +677,15 @@ where
 }
 
 /// Resolves the value of a field that corresponds to a named type.
-fn resolve_field_value_for_named_type<'a, R>(
-    ctx: &ExecutionContext<'a, R>,
+fn resolve_field_value_for_named_type(
+    ctx: &ExecutionContext<impl Resolver>,
     object_type: &s::ObjectType,
     object_value: &Option<q::Value>,
     field: &q::Field,
     field_definition: &s::Field,
     type_name: &s::Name,
     argument_values: &HashMap<&q::Name, q::Value>,
-) -> Result<q::Value, Vec<QueryExecutionError>>
-where
-    R: Resolver,
-{
+) -> Result<q::Value, Vec<QueryExecutionError>> {
     // Try to resolve the type name into the actual type
     let named_type = sast::get_named_type(&ctx.schema.document, type_name)
         .ok_or_else(|| QueryExecutionError::NamedTypeError(type_name.to_string()))?;
@@ -762,18 +741,15 @@ where
 }
 
 /// Resolves the value of a field that corresponds to a list type.
-fn resolve_field_value_for_list_type<'a, R>(
-    ctx: &ExecutionContext<'a, R>,
+fn resolve_field_value_for_list_type(
+    ctx: &ExecutionContext<impl Resolver>,
     object_type: &s::ObjectType,
     object_value: &Option<q::Value>,
     field: &q::Field,
     field_definition: &s::Field,
     inner_type: &s::Type,
     argument_values: &HashMap<&q::Name, q::Value>,
-) -> Result<q::Value, Vec<QueryExecutionError>>
-where
-    R: Resolver,
-{
+) -> Result<q::Value, Vec<QueryExecutionError>> {
     match inner_type {
         s::Type::NonNullType(inner_type) => resolve_field_value_for_list_type(
             ctx,
@@ -858,16 +834,13 @@ where
 }
 
 /// Ensures that a value matches the expected return type.
-fn complete_value<'a, R>(
-    ctx: &ExecutionContext<'a, R>,
-    field: &'a q::Field,
-    field_type: &'a s::Type,
-    fields: Vec<&'a q::Field>,
+fn complete_value(
+    ctx: &ExecutionContext<impl Resolver>,
+    field: &q::Field,
+    field_type: &s::Type,
+    fields: Vec<&q::Field>,
     resolved_value: q::Value,
-) -> Result<q::Value, Vec<QueryExecutionError>>
-where
-    R: Resolver,
-{
+) -> Result<q::Value, Vec<QueryExecutionError>> {
     match field_type {
         // Fail if the field type is non-null but the value is null
         s::Type::NonNullType(inner_type) => {
@@ -987,14 +960,11 @@ where
 }
 
 /// Resolves an abstract type (interface, union) into an object type based on the given value.
-fn resolve_abstract_type<'a, R>(
-    ctx: &'a ExecutionContext<'a, R>,
-    abstract_type: &'a s::TypeDefinition,
+fn resolve_abstract_type<'a>(
+    ctx: &'a ExecutionContext<impl Resolver>,
+    abstract_type: &s::TypeDefinition,
     object_value: &q::Value,
-) -> Result<&'a s::ObjectType, Vec<QueryExecutionError>>
-where
-    R: Resolver,
-{
+) -> Result<&'a s::ObjectType, Vec<QueryExecutionError>> {
     // Let the resolver handle the type resolution, return an error if the resolution
     // yields nothing
     ctx.resolver
@@ -1035,14 +1005,11 @@ pub fn merge_selection_sets(fields: Vec<&q::Field>) -> q::SelectionSet {
 }
 
 /// Coerces argument values into GraphQL values.
-pub fn coerce_argument_values<'a, R>(
-    ctx: &ExecutionContext<'_, R>,
+pub fn coerce_argument_values<'a>(
+    ctx: &ExecutionContext<impl Resolver>,
     object_type: &'a s::ObjectType,
     field: &q::Field,
-) -> Result<HashMap<&'a q::Name, q::Value>, Vec<QueryExecutionError>>
-where
-    R: Resolver,
-{
+) -> Result<HashMap<&'a q::Name, q::Value>, Vec<QueryExecutionError>> {
     let mut coerced_values = HashMap::new();
     let mut errors = vec![];
 

graphql/src/execution/resolver.rs

@@ -64,9 +64,9 @@ impl<'a> ObjectOrInterface<'a> {
 /// A GraphQL resolver that can resolve entities, enum values, scalar types and interfaces/unions.
 pub trait Resolver: Clone + Send + Sync {
     /// Prepare for executing a query by prefetching as much data as possible
-    fn prefetch<'a>(
+    fn prefetch(
         &self,
-        ctx: &ExecutionContext<'a, Self>,
+        ctx: &ExecutionContext<Self>,
         selection_set: &q::SelectionSet,
     ) -> Result<Option<q::Value>, Vec<QueryExecutionError>>;
 

graphql/src/introspection/resolver.rs

@@ -456,9 +456,9 @@ impl<'a> IntrospectionResolver<'a> {
 
 /// A GraphQL resolver that can resolve entities, enum values, scalar types and interfaces/unions.
 impl<'a> Resolver for IntrospectionResolver<'a> {
-    fn prefetch<'r>(
+    fn prefetch(
         &self,
-        _: &ExecutionContext<'r, Self>,
+        _: &ExecutionContext<Self>,
         _: &q::SelectionSet,
     ) -> Result<Option<q::Value>, Vec<QueryExecutionError>> {
         Ok(None)

graphql/src/query/mod.rs

@@ -76,7 +76,7 @@ where
         logger: query_logger.clone(),
         resolver: Arc::new(options.resolver),
         schema: query.schema.clone(),
-        document: &query.document,
+        document: query.document.clone(),
         fields: vec![],
         variable_values: Arc::new(coerced_variable_values),
         deadline: options.deadline,