neo4j-driver-bolt-connection
Version:
Implements the connection with the Neo4j Database using the Bolt Protocol
160 lines (159 loc) • 6.63 kB
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 __assign = (this && this.__assign) || function () {
__assign = Object.assign || function(t) {
for (var s, i = 1, n = arguments.length; i < n; i++) {
s = arguments[i];
for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p))
t[p] = s[p];
}
return t;
};
return __assign.apply(this, arguments);
};
var __importDefault = (this && this.__importDefault) || function (mod) {
return (mod && mod.__esModule) ? mod : { "default": mod };
};
Object.defineProperty(exports, "__esModule", { value: true });
var bolt_protocol_v5x8_transformer_1 = __importDefault(require("./bolt-protocol-v5x8.transformer"));
var transformer_1 = require("./transformer");
var packstream_1 = require("../packstream");
var neo4j_driver_core_1 = require("neo4j-driver-core");
var VECTOR = 0x56;
var FLOAT_32 = 0xc6;
var FLOAT_64 = 0xc1;
var INT_8 = 0xc8;
var INT_16 = 0xc9;
var INT_32 = 0xca;
var INT_64 = 0xcb;
var UNSUPPORTED = 0x3F;
var typeToTypeMarker = {
INT8: INT_8,
INT16: INT_16,
INT32: INT_32,
INT64: INT_64,
FLOAT32: FLOAT_32,
FLOAT64: FLOAT_64
};
function createVectorTransformer() {
return new transformer_1.TypeTransformer({
signature: VECTOR,
isTypeInstance: function (object) { return (0, neo4j_driver_core_1.isVector)(object); },
toStructure: function (vector) {
var typeMarker = typeToTypeMarker[vector.getType()];
if (typeMarker === undefined) {
throw (0, neo4j_driver_core_1.newError)("Vector object has unknown type: ".concat(vector.getType()));
}
var buffer = fixBufferEndianness(typeMarker, vector.asTypedArray().buffer);
var struct = new packstream_1.structure.Structure(VECTOR, [Int8Array.from([typeMarker]), new Int8Array(buffer)]);
return struct;
},
fromStructure: function (structure) {
var typeMarker = Uint8Array.from(structure.fields[0])[0];
var byteArray = structure.fields[1];
var buffer = fixBufferEndianness(typeMarker, byteArray.buffer);
switch (typeMarker) {
case INT_8:
return new neo4j_driver_core_1.Vector(new Int8Array(buffer));
case INT_16:
return new neo4j_driver_core_1.Vector(new Int16Array(buffer));
case INT_32:
return new neo4j_driver_core_1.Vector(new Int32Array(buffer));
case INT_64:
return new neo4j_driver_core_1.Vector(new BigInt64Array(buffer));
case FLOAT_32:
return new neo4j_driver_core_1.Vector(new Float32Array(buffer));
case FLOAT_64:
return new neo4j_driver_core_1.Vector(new Float64Array(buffer));
default:
throw (0, neo4j_driver_core_1.newError)("Received Vector structure with unsupported type marker: ".concat(typeMarker));
}
}
});
}
function fixBufferEndianness(typeMarker, buffer) {
var isLittleEndian = checkLittleEndian();
if (isLittleEndian) {
var setview = new DataView(new ArrayBuffer(buffer.byteLength));
// we want exact byte accuracy, so we cannot simply get the value from the typed array
var getview = new DataView(buffer);
var set = void 0;
var get = void 0;
var elementSize = void 0;
switch (typeMarker) {
case INT_8:
elementSize = 1;
set = setview.setInt8.bind(setview);
get = getview.getInt8.bind(getview);
break;
case INT_16:
elementSize = 2;
set = setview.setInt16.bind(setview);
get = getview.getInt16.bind(getview);
break;
case INT_32:
elementSize = 4;
set = setview.setInt32.bind(setview);
get = getview.getInt32.bind(getview);
break;
case INT_64:
elementSize = 8;
set = setview.setBigInt64.bind(setview);
get = getview.getBigInt64.bind(getview);
break;
case FLOAT_32:
elementSize = 4;
set = setview.setInt32.bind(setview);
get = getview.getInt32.bind(getview);
break;
case FLOAT_64:
elementSize = 8;
set = setview.setBigInt64.bind(setview);
get = getview.getBigInt64.bind(getview);
break;
default:
throw (0, neo4j_driver_core_1.newError)("Vector is of unsupported type ".concat(typeMarker));
}
for (var i = 0; i < buffer.byteLength; i += elementSize) {
set(i, get(i, isLittleEndian));
}
return setview.buffer;
}
else {
return buffer;
}
}
function checkLittleEndian() {
var dataview = new DataView(new ArrayBuffer(2));
dataview.setInt16(0, 1000, true);
var typeArray = new Int16Array(dataview.buffer);
return typeArray[0] === 1000;
}
function createUnsupportedTypeTransformer() {
return new transformer_1.TypeTransformer({
signature: UNSUPPORTED,
isTypeInstance: function (object) { return (0, neo4j_driver_core_1.isUnsupportedType)(object); },
toStructure: function (_) {
throw (0, neo4j_driver_core_1.newError)('UnsupportedType object can not be transmitted');
},
fromStructure: function (structure) {
return new neo4j_driver_core_1.UnsupportedType(structure.fields[0], structure.fields[1], structure.fields[2], structure.fields[3].message);
}
});
}
exports.default = __assign(__assign({}, bolt_protocol_v5x8_transformer_1.default), { createVectorTransformer: createVectorTransformer, createUnsupportedTypeTransformer: createUnsupportedTypeTransformer });