STRLCPY/graphql-engine

Allow nulls when expecting object or array in response (#440)

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## Description

Fix a bug which was causing an internal error when `null` was returned
by NDC for a field of array or object type.

### Product
_(Select all products this will be available in)_
- [x] community-edition
- [x] cloud
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### Type
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- [ ] highlight
- [ ] enhancement
- [x] bugfix
- [ ] behaviour-change
- [ ] performance-enhancement
- [ ] security-fix
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### Changelog entry
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Fix a bug which was causing an internal error when `null` was returned
by NDC for a field of array or object type.

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<!-- changelog : end : DO NOT REMOVE -->

V3_GIT_ORIGIN_REV_ID: 5c935ccd6720b5e5966dfa87c2e21dbb7a2b36f2

David Overton committed with hasura-bot 1 month ago

9a6cb644

1 parent 0e822cc9

Revision indexing in progress... (symbol navigation in revisions will be accurate after indexed)

Total 6 files Show one by one

■ ■ ■ ■ ■ ■

v3/crates/custom-connector/data/institutions.json

1	1		{ "id": 1, "name": "Queen Mary University of London", "location": { "city": "London", "country": "UK", "campuses": ["Mile End", "Whitechapel", "Charterhouse Square", "West Smithfield"] }, "staff": [ { "first_name": "Peter", "last_name": "Landin", "specialities": ["Computer Science", "Education"], "favourite_artist_id": 1 } ], "departments": ["Humanities and Social Sciences", "Science and Engineering", "Medicine and Dentistry"] }
2	2		{ "id": 2, "name": "Chalmers University of Technology", "location": { "city": "Gothenburg", "country": "Sweden", "campuses": ["Johanneberg", "Lindholmen"] }, "staff": [ { "first_name": "John", "last_name": "Hughes", "specialities": ["Computer Science", "Functional Programming", "Software Testing"], "favourite_artist_id": 2 }, { "first_name": "Koen", "last_name": "Claessen", "specialities": ["Computer Science", "Functional Programming", "Automated Reasoning"], "favourite_artist_id": 3 } ], "departments": ["Architecture and Civil Engineering", "Computer Science and Engineering", "Electrical Engineering", "Physics", "Industrial and Materials Science"] }
	3	+	{ "id": 3, "name": "University of Nowhere", "location": null, "staff": null, "departments": ["nothing", null]}

■ ■ ■ ■ ■ ■

v3/crates/engine/src/execute/process_response.rs

		skipped 245 lines
246	246		value: json::Value,
247	247		selection_set: &normalized_ast::SelectionSet<'_, GDS>,
248	248		) -> Result<json::Value, error::Error> {
249		-	if selection_set.fields.is_empty() {
	249	+	if selection_set.fields.is_empty() \|\| value.is_null() {
	250	+	// If selection set is empty we return the whole value without further processing.
	251	+	// If the value is null we have nothing to process so we return null.
250	252		Ok(value)
251	253		} else {
252	254		let rows: Vec<IndexMap<String, ndc_models::RowFieldValue>> = json::from_value(value)?;
		skipped 9 lines
262	264		value: json::Value,
263	265		selection_set: &normalized_ast::SelectionSet<'_, GDS>,
264	266		) -> Result<json::Value, error::Error> {
265		-	if selection_set.fields.is_empty() {
	267	+	if selection_set.fields.is_empty() \|\| value.is_null() {
	268	+	// If selection set is empty we return the whole value without further processing.
	269	+	// If the value is null we have nothing to process so we return null.
266	270		Ok(value)
267	271		} else {
268	272		let row: IndexMap<String, ndc_models::RowFieldValue> = json::from_value(value)?;
		skipped 172 lines

■ ■ ■ ■ ■ ■

v3/crates/engine/src/execute/remote_joins/collect.rs

		skipped 197 lines
198	198		serde_json::Value::Object(_) => {
199	199		serde_json::from_value(this.0).ok().map(\|v\| vec![v])
200	200		}
	201	+	serde_json::Value::Null => Some(vec![]),
201	202		_ => None,
202	203		}
203	204		}
		skipped 98 lines

■ ■ ■ ■ ■ ■

v3/crates/engine/tests/execute/models/select_many/nested_select/expected.json

		skipped 79 lines
80	80		"Physics",
81	81		"Industrial and Materials Science"
82	82		]
	83	+	},
	84	+	{
	85	+	"id": 3,
	86	+	"location": null,
	87	+	"location_country": null,
	88	+	"staff": null,
	89	+	"staff_first_name": null,
	90	+	"departments": [
	91	+	"nothing",
	92	+	null
	93	+	]
83	94		}
84	95		]
85	96		}
		skipped 1 lines

■ ■ ■ ■ ■ ■

v3/crates/engine/tests/execute/models/select_many/nested_select/no_explicit_type_mapping/expected.json

		skipped 79 lines
80	80		"Physics",
81	81		"Industrial and Materials Science"
82	82		]
	83	+	},
	84	+	{
	85	+	"id": 3,
	86	+	"location": null,
	87	+	"location_country": null,
	88	+	"staff": null,
	89	+	"staff_first_name": null,
	90	+	"departments": [
	91	+	"nothing",
	92	+	null
	93	+	]
83	94		}
84	95		]
85	96		}
		skipped 1 lines

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v3/crates/engine/tests/execute/remote_relationships/from_nested/expected.json

		skipped 32 lines
33	33		}
34	34		}
35	35		]
	36	+	},
	37	+	{
	38	+	"staff": null
36	39		}
37	40		]
38	41		}
		skipped 32 lines
71	74		}
72	75		}
73	76		]
	77	+	},
	78	+	{
	79	+	"staff": null
74	80		}
75	81		]
76	82		}
		skipped 32 lines
109	115		}
110	116		}
111	117		]
	118	+	},
	119	+	{
	120	+	"staff": null
112	121		}
113	122		]
114	123		}
		skipped 32 lines
147	156		}
148	157		}
149	158		]
	159	+	},
	160	+	{
	161	+	"staff": null
150	162		}
151	163		]
152	164		}
		skipped 2 lines