This repository has been archived by the owner on Apr 15, 2020. It is now read-only.
forked from ardatan/graphql-tools
-
Notifications
You must be signed in to change notification settings - Fork 5
/
delegateToSchema.ts
192 lines (170 loc) · 5.2 KB
/
delegateToSchema.ts
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
import {
ArgumentNode,
DocumentNode,
FieldNode,
FragmentDefinitionNode,
Kind,
OperationDefinitionNode,
SelectionSetNode,
SelectionNode,
subscribe,
execute,
validate,
VariableDefinitionNode,
GraphQLSchema,
ExecutionResult,
NameNode,
isEnumType,
} from 'graphql';
import { Operation, Request, IDelegateToSchemaOptions } from '../Interfaces';
import {
applyRequestTransforms,
applyResultTransforms,
} from '../transforms/transforms';
import AddArgumentsAsVariables from '../transforms/AddArgumentsAsVariables';
import FilterToSchema from '../transforms/FilterToSchema';
import AddTypenameToAbstract from '../transforms/AddTypenameToAbstract';
import CheckResultAndHandleErrors from '../transforms/CheckResultAndHandleErrors';
import mapAsyncIterator from './mapAsyncIterator';
import ExpandAbstractTypes from '../transforms/ExpandAbstractTypes';
import ReplaceFieldWithFragment from '../transforms/ReplaceFieldWithFragment';
import ConvertEnumResponse from '../transforms/ConvertEnumResponse';
export default function delegateToSchema(
options: IDelegateToSchemaOptions | GraphQLSchema,
...args: any[]
): Promise<any> {
if (options instanceof GraphQLSchema) {
throw new Error(
'Passing positional arguments to delegateToSchema is a deprecated. ' +
'Please pass named parameters instead.',
);
}
return delegateToSchemaImplementation(options);
}
async function delegateToSchemaImplementation(
options: IDelegateToSchemaOptions,
): Promise<any> {
const { info, args = {} } = options;
const operation = options.operation || info.operation.operation;
const rawDocument: DocumentNode = createDocument(
options.fieldName,
operation,
info.fieldNodes,
Object.keys(info.fragments).map(
fragmentName => info.fragments[fragmentName],
),
info.operation.variableDefinitions,
info.operation.name,
);
const rawRequest: Request = {
document: rawDocument,
variables: info.variableValues as Record<string, any>,
};
let transforms = [
...(options.transforms || []),
new ExpandAbstractTypes(info.schema, options.schema),
];
if (info.mergeInfo && info.mergeInfo.fragments) {
transforms.push(
new ReplaceFieldWithFragment(options.schema, info.mergeInfo.fragments),
);
}
transforms = transforms.concat([
new AddArgumentsAsVariables(options.schema, args),
new FilterToSchema(options.schema),
new AddTypenameToAbstract(options.schema),
new CheckResultAndHandleErrors(info, options.fieldName),
]);
if (isEnumType(options.info.returnType)) {
transforms = transforms.concat(
new ConvertEnumResponse(options.info.returnType),
);
}
const processedRequest = applyRequestTransforms(rawRequest, transforms);
if (!options.skipValidation) {
const errors = validate(options.schema, processedRequest.document);
if (errors.length > 0) {
throw errors;
}
}
if (operation === 'query' || operation === 'mutation') {
return applyResultTransforms(
await execute(
options.schema,
processedRequest.document,
info.rootValue,
options.context,
processedRequest.variables,
),
transforms,
);
}
if (operation === 'subscription') {
const executionResult = (await subscribe(
options.schema,
processedRequest.document,
info.rootValue,
options.context,
processedRequest.variables,
)) as AsyncIterator<ExecutionResult>;
// "subscribe" to the subscription result and map the result through the transforms
return mapAsyncIterator<ExecutionResult, any>(executionResult, result => {
const transformedResult = applyResultTransforms(result, transforms);
// wrap with fieldName to return for an additional round of resolutioon
// with payload as rootValue
return {
[info.fieldName]: transformedResult,
};
});
}
}
function createDocument(
targetField: string,
targetOperation: Operation,
originalSelections: ReadonlyArray<SelectionNode>,
fragments: Array<FragmentDefinitionNode>,
variables: ReadonlyArray<VariableDefinitionNode>,
operationName: NameNode,
): DocumentNode {
let selections: Array<SelectionNode> = [];
let args: Array<ArgumentNode> = [];
originalSelections.forEach((field: FieldNode) => {
const fieldSelections = field.selectionSet
? field.selectionSet.selections
: [];
selections = selections.concat(fieldSelections);
args = args.concat(field.arguments || []);
});
let selectionSet = null;
if (selections.length > 0) {
selectionSet = {
kind: Kind.SELECTION_SET,
selections: selections,
};
}
const rootField: FieldNode = {
kind: Kind.FIELD,
alias: null,
arguments: args,
selectionSet,
name: {
kind: Kind.NAME,
value: targetField,
},
};
const rootSelectionSet: SelectionSetNode = {
kind: Kind.SELECTION_SET,
selections: [rootField],
};
const operationDefinition: OperationDefinitionNode = {
kind: Kind.OPERATION_DEFINITION,
operation: targetOperation,
variableDefinitions: variables,
selectionSet: rootSelectionSet,
name: operationName,
};
return {
kind: Kind.DOCUMENT,
definitions: [operationDefinition, ...fragments],
};
}