neo4j-driver-core
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Internals of neo4j-driver
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JavaScript
;
/**
* Copyright (c) "Neo4j"
* Neo4j Sweden AB [https://neo4j.com]
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }
return new (P || (P = Promise))(function (resolve, reject) {
function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); }
step((generator = generator.apply(thisArg, _arguments || [])).next());
});
};
var __generator = (this && this.__generator) || function (thisArg, body) {
var _ = { label: 0, sent: function() { if (t[0] & 1) throw t[1]; return t[1]; }, trys: [], ops: [] }, f, y, t, g;
return g = { next: verb(0), "throw": verb(1), "return": verb(2) }, typeof Symbol === "function" && (g[Symbol.iterator] = function() { return this; }), g;
function verb(n) { return function (v) { return step([n, v]); }; }
function step(op) {
if (f) throw new TypeError("Generator is already executing.");
while (g && (g = 0, op[0] && (_ = 0)), _) try {
if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
if (y = 0, t) op = [op[0] & 2, t.value];
switch (op[0]) {
case 0: case 1: t = op; break;
case 4: _.label++; return { value: op[1], done: false };
case 5: _.label++; y = op[1]; op = [0]; continue;
case 7: op = _.ops.pop(); _.trys.pop(); continue;
default:
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op = body.call(thisArg, _);
} catch (e) { op = [6, e]; y = 0; } finally { f = t = 0; }
if (op[0] & 5) throw op[1]; return { value: op[0] ? op[1] : void 0, done: true };
}
};
var __importDefault = (this && this.__importDefault) || function (mod) {
return (mod && mod.__esModule) ? mod : { "default": mod };
};
Object.defineProperty(exports, "__esModule", { value: true });
var result_eager_1 = __importDefault(require("./result-eager"));
var error_1 = require("./error");
function createEagerResultFromResult(result) {
return __awaiter(this, void 0, void 0, function () {
var _a, summary, records, keys;
return __generator(this, function (_b) {
switch (_b.label) {
case 0: return [4 /*yield*/, result];
case 1:
_a = _b.sent(), summary = _a.summary, records = _a.records;
return [4 /*yield*/, result.keys()];
case 2:
keys = _b.sent();
return [2 /*return*/, new result_eager_1.default(keys, records, summary)];
}
});
});
}
/**
* Protocol for transforming {@link Result}.
*
* @typedef {function<T>(result:Result):Promise<T>} ResultTransformer
* @interface
*
* @see {@link resultTransformers} for provided implementations.
* @see {@link Driver#executeQuery} for usage.
*/
/**
* Defines the object which holds the common {@link ResultTransformer} used with {@link Driver#executeQuery}.
*/
var ResultTransformers = /** @class */ (function () {
function ResultTransformers() {
}
/**
* Creates a {@link ResultTransformer} which transforms {@link Result} to {@link EagerResult}
* by consuming the whole stream.
*
* This is the default implementation used in {@link Driver#executeQuery}
*
* @example
* // This:
* const { keys, records, summary } = await driver.executeQuery('CREATE (p:Person{ name: $name }) RETURN p', { name: 'Person1'}, {
* resultTransformer: neo4j.resultTransformers.eagerResultTransformer()
* })
* // is equivalent to:
* const { keys, records, summary } = await driver.executeQuery('CREATE (p:Person{ name: $name }) RETURN p', { name: 'Person1'})
*
* @returns {ResultTransformer<EagerResult<Entries>>} The result transformer
*/
ResultTransformers.prototype.eagerResultTransformer = function () {
return createEagerResultFromResult;
};
/**
* Creates a {@link ResultTransformer} which maps the {@link Record} in the result and collects it
* along with the {@link ResultSummary} and {@link Result#keys}.
*
* NOTE: The config object requires map or/and collect to be valid.
*
* @example
* // Mapping the records
* const { keys, records, summary } = await driver.executeQuery('MATCH (p:Person{ age: $age }) RETURN p.name as name', { age: 25 }, {
* resultTransformer: neo4j.resultTransformers.mappedResultTransformer({
* map(record) {
* return record.get('name')
* }
* })
* })
*
* records.forEach(name => console.log(`${name} has 25`))
*
* @example
* // Mapping records and collect result
* const names = await driver.executeQuery('MATCH (p:Person{ age: $age }) RETURN p.name as name', { age: 25 }, {
* resultTransformer: neo4j.resultTransformers.mappedResultTransformer({
* map(record) {
* return record.get('name')
* },
* collect(records, summary, keys) {
* return records
* }
* })
* })
*
* names.forEach(name => console.log(`${name} has 25`))
*
* @example
* // The transformer can be defined one and used everywhere
* const getRecordsAsObjects = neo4j.resultTransformers.mappedResultTransformer({
* map(record) {
* return record.toObject()
* },
* collect(objects) {
* return objects
* }
* })
*
* // The usage in a driver.executeQuery
* const objects = await driver.executeQuery('MATCH (p:Person{ age: $age }) RETURN p.name as name', { age: 25 }, {
* resultTransformer: getRecordsAsObjects
* })
* objects.forEach(object => console.log(`${object.name} has 25`))
*
*
* // The usage in session.executeRead
* const objects = await session.executeRead(tx => getRecordsAsObjects(tx.run('MATCH (p:Person{ age: $age }) RETURN p.name as name')))
* objects.forEach(object => console.log(`${object.name} has 25`))
*
* @param {object} config The result transformer configuration
* @param {function(record:Record):R} [config.map=function(record) { return record }] Method called for mapping each record
* @param {function(records:R[], summary:ResultSummary, keys:string[]):T} [config.collect=function(records, summary, keys) { return { records, summary, keys }}] Method called for mapping
* the result data to the transformer output.
* @returns {ResultTransformer<T>} The result transformer
* @see {@link Driver#executeQuery}
*/
ResultTransformers.prototype.mappedResultTransformer = function (config) {
var _this = this;
if (config == null || (config.collect == null && config.map == null)) {
throw (0, error_1.newError)('Requires a map or/and a collect functions.');
}
return function (result) { return __awaiter(_this, void 0, void 0, function () {
return __generator(this, function (_a) {
switch (_a.label) {
case 0: return [4 /*yield*/, new Promise(function (resolve, reject) {
var state = { records: [], keys: [] };
result.subscribe({
onKeys: function (keys) {
state.keys = keys;
},
onNext: function (record) {
if (config.map != null) {
var mappedRecord = config.map(record);
if (mappedRecord !== undefined) {
state.records.push(mappedRecord);
}
}
else {
state.records.push(record);
}
},
onCompleted: function (summary) {
if (config.collect != null) {
resolve(config.collect(state.records, summary, state.keys));
}
else {
var obj = { records: state.records, summary: summary, keys: state.keys };
resolve(obj);
}
},
onError: function (error) {
reject(error);
}
});
})];
case 1: return [2 /*return*/, _a.sent()];
}
});
}); };
};
return ResultTransformers;
}());
/**
* Holds the common {@link ResultTransformer} used with {@link Driver#executeQuery}.
*/
var resultTransformers = new ResultTransformers();
Object.freeze(resultTransformers);
exports.default = resultTransformers;