blob: 0ad5197a5bd09bea613aff7f5145992ee99f3d3a [file] [log] [blame]
import objectValues from "../polyfills/objectValues.mjs";
import keyMap from "../jsutils/keyMap.mjs";
import inspect from "../jsutils/inspect.mjs";
import invariant from "../jsutils/invariant.mjs";
import { Kind } from "../language/kinds.mjs";
import { isLeafType, isInputObjectType, isListType, isNonNullType } from "../type/definition.mjs";
/**
* Produces a JavaScript value given a GraphQL Value AST.
*
* A GraphQL type must be provided, which will be used to interpret different
* GraphQL Value literals.
*
* Returns `undefined` when the value could not be validly coerced according to
* the provided type.
*
* | GraphQL Value | JSON Value |
* | -------------------- | ------------- |
* | Input Object | Object |
* | List | Array |
* | Boolean | Boolean |
* | String | String |
* | Int / Float | Number |
* | Enum Value | Mixed |
* | NullValue | null |
*
*/
export function valueFromAST(valueNode, type, variables) {
if (!valueNode) {
// When there is no node, then there is also no value.
// Importantly, this is different from returning the value null.
return;
}
if (valueNode.kind === Kind.VARIABLE) {
var variableName = valueNode.name.value;
if (variables == null || variables[variableName] === undefined) {
// No valid return value.
return;
}
var variableValue = variables[variableName];
if (variableValue === null && isNonNullType(type)) {
return; // Invalid: intentionally return no value.
} // Note: This does no further checking that this variable is correct.
// This assumes that this query has been validated and the variable
// usage here is of the correct type.
return variableValue;
}
if (isNonNullType(type)) {
if (valueNode.kind === Kind.NULL) {
return; // Invalid: intentionally return no value.
}
return valueFromAST(valueNode, type.ofType, variables);
}
if (valueNode.kind === Kind.NULL) {
// This is explicitly returning the value null.
return null;
}
if (isListType(type)) {
var itemType = type.ofType;
if (valueNode.kind === Kind.LIST) {
var coercedValues = [];
for (var _i2 = 0, _valueNode$values2 = valueNode.values; _i2 < _valueNode$values2.length; _i2++) {
var itemNode = _valueNode$values2[_i2];
if (isMissingVariable(itemNode, variables)) {
// If an array contains a missing variable, it is either coerced to
// null or if the item type is non-null, it considered invalid.
if (isNonNullType(itemType)) {
return; // Invalid: intentionally return no value.
}
coercedValues.push(null);
} else {
var itemValue = valueFromAST(itemNode, itemType, variables);
if (itemValue === undefined) {
return; // Invalid: intentionally return no value.
}
coercedValues.push(itemValue);
}
}
return coercedValues;
}
var coercedValue = valueFromAST(valueNode, itemType, variables);
if (coercedValue === undefined) {
return; // Invalid: intentionally return no value.
}
return [coercedValue];
}
if (isInputObjectType(type)) {
if (valueNode.kind !== Kind.OBJECT) {
return; // Invalid: intentionally return no value.
}
var coercedObj = Object.create(null);
var fieldNodes = keyMap(valueNode.fields, function (field) {
return field.name.value;
});
for (var _i4 = 0, _objectValues2 = objectValues(type.getFields()); _i4 < _objectValues2.length; _i4++) {
var field = _objectValues2[_i4];
var fieldNode = fieldNodes[field.name];
if (!fieldNode || isMissingVariable(fieldNode.value, variables)) {
if (field.defaultValue !== undefined) {
coercedObj[field.name] = field.defaultValue;
} else if (isNonNullType(field.type)) {
return; // Invalid: intentionally return no value.
}
continue;
}
var fieldValue = valueFromAST(fieldNode.value, field.type, variables);
if (fieldValue === undefined) {
return; // Invalid: intentionally return no value.
}
coercedObj[field.name] = fieldValue;
}
return coercedObj;
}
/* istanbul ignore else */
if (isLeafType(type)) {
// Scalars and Enums fulfill parsing a literal value via parseLiteral().
// Invalid values represent a failure to parse correctly, in which case
// no value is returned.
var result;
try {
result = type.parseLiteral(valueNode, variables);
} catch (_error) {
return; // Invalid: intentionally return no value.
}
if (result === undefined) {
return; // Invalid: intentionally return no value.
}
return result;
} // Not reachable. All possible input types have been considered.
/* istanbul ignore next */
invariant(false, 'Unexpected input type: ' + inspect(type));
} // Returns true if the provided valueNode is a variable which is not defined
// in the set of variables.
function isMissingVariable(valueNode, variables) {
return valueNode.kind === Kind.VARIABLE && (variables == null || variables[valueNode.name.value] === undefined);
}