add payload fields to Response section

Author: robrichard

spec/Section 3 -- Type System.md

@@ -1753,7 +1753,12 @@ A GraphQL schema describes directives which are used to annotate various parts
 of a GraphQL document as an indicator that they should be evaluated differently
 by a validator, executor, or client tool such as a code generator.
 
-GraphQL implementations should provide the `@skip`, `@include`, `@defer` and `@stream` directives.
+GraphQL implementations should provide the `@skip` and `@include` directives. 
+
+GraphQL implementations are not required to implement the `@defer` and `@stream` 
+directives. If they are implemented, they must be implemented according to the
+specification. GraphQL implementations that do not support these directives must
+not make them available via introspection.
 
 GraphQL implementations that support the type system definition language must
 provide the `@deprecated` directive if representing deprecated portions of

spec/Section 6 -- Execution.md

@@ -141,6 +141,10 @@ ExecuteQuery(query, schema, variableValues, initialValue):
   * For each {payload} in {subsequentPayloads}:
     * If {payload} is a Deferred Fragment Record:
       * Yield the value from calling {ResolveDeferredFragmentRecord(payload, variableValues, subsequentPayloads)}.
+      * If {payload} is not the final payload in {subsequentPayloads}
+        * Add an entry to {payload} named `hasNext` with the value {true}.
+      * If {payload} is the final payload in {subsequentPayloads}
+        * Add an entry to {payload} named `hasNext` with the value {false}.
     * If {payload} is a Stream Record:
       * Yield ResolveStreamRecord(payload, variableValues, subsequentPayloads).
 
@@ -712,7 +716,7 @@ Note: It is common for {resolver} to be asynchronous due to relying on reading
 an underlying database or networked service to produce a value. This
 necessitates the rest of a GraphQL executor to handle an asynchronous
 execution flow. In addition, a commom implementation of {generator} is to leverage 
-asynchronos iterators or asynchronos generators provided by many programing languages.
+asynchronous iterators or asynchronous generators provided by many programing languages.
 
 ### Value Completion
 

spec/Section 7 -- Response.md

@@ -8,11 +8,11 @@ request.
 A response may contain both a partial response as well as encountered errors in
 the case that a field error occurred on a field which was replaced with {null}.
 
+A response to a GraphQL operation must be a map or an event stream of maps. The
+value of this map is described in the "Response Format" section.
 
 ## Response Format
 
-A response to a GraphQL operation must be a map.
-
 If the operation encountered any errors, the response map must contain an
 entry with key `errors`. The value of this entry is described in the "Errors"
 section. If the operation completed without encountering any errors, this entry
@@ -23,11 +23,24 @@ with key `data`. The value of this entry is described in the "Data" section. If
 the operation failed before execution, due to a syntax error, missing
 information, or validation error, this entry must not be present.
 
+If the response of the GraphQL operation is an event stream, each response map
+must contain an entry with key `hasNext`. The value of this entry is `true` for
+all but the last response in the stream. The value of this entry is `false` for 
+the last response of the stream. This entry is not required for GraphQL 
+operations that return a single response map.
+
 The response map may also contain an entry with key `extensions`. This entry,
 if set, must have a map as its value. This entry is reserved for implementors
 to extend the protocol however they see fit, and hence there are no additional
 restrictions on its contents.
 
+When the response of the GraphQL operation is an event stream, the first value
+will be the initial response. All subsequent values must contain `label` and 
+`path` entries. These two entries are used by clients to identify the the 
+`@defer` or `@stream` directive from the GraphQL operation that triggered this
+value to be returned by the event stream. The combination of these two entries
+must be unique across all values returned by the event stream.
+
 To ensure future changes to the protocol do not break existing servers and
 clients, the top level response map must not contain any entries other than the
 three described above.
@@ -43,6 +56,11 @@ requested operation. If the operation was a query, this output will be an
 object of the schema's query root type; if the operation was a mutation, this
 output will be an object of the schema's mutation root type.
 
+If the result of the operation is an event stream, the `data` entry in 
+subsequent values will be an object of the type of a particular field in the
+GraphQL result. The adjacent `path` field will contain the path segments of 
+the field this data is associated with.
+
 If an error was encountered before execution begins, the `data` entry should
 not be present in the result.
 
@@ -82,14 +100,8 @@ associated syntax element.
 If an error can be associated to a particular field in the GraphQL result, it
 must contain an entry with the key `path` that details the path of the
 response field which experienced the error. This allows clients to identify
-whether a `null` result is intentional or caused by a runtime error.
-
-This field should be a list of path segments starting at the root of the
-response and ending with the field associated with the error. Path segments
-that represent fields should be strings, and path segments that
-represent list indices should be 0-indexed integers. If the error happens
-in an aliased field, the path to the error should use the aliased name, since
-it represents a path in the response, not in the query.
+whether a `null` result is intentional or caused by a runtime error. The value 
+of this field is described in the "Path" section.
 
 For example, if fetching one of the friends' names fails in the following
 query:
@@ -220,6 +232,29 @@ still discouraged.
 ```
 
 
+## Path
+
+A `path` field allows for the association to a particular field in a GraphQL 
+result. This field should be a list of path segments starting at the root of the
+response and ending with the field to be associated with. Path segments
+that represent fields should be strings, and path segments that
+represent list indices should be 0-indexed integers. If the path is associated to
+an aliased field, the path should use the aliased name, since it represents a path in the response, not in the query.
+
+When the `path` field is present on a GraphQL response, it indicates that the 
+`data` field is not the root query or mutation result, but is rather associated to
+a particular field in the root result.
+
+When the `path` field is present on an "Error result", it indicates the response field which experienced the error.
+
+## Label
+
+If the response of the GraphQL operation is an event stream, subsequent values
+will contain a string field `label`. This `label` is the same label passed to 
+the `@defer` or `@stream` directive that triggered this value. This allows 
+clients to identify which `@defer` or `@stream` directive is associated with
+this value.
+
 ## Serialization Format
 
 GraphQL does not require a specific serialization format. However, clients