UNPKG

@dfinity/candid

Version:

JavaScript and TypeScript library to work with candid interfaces

1,458 lines 76.6 kB
"use strict"; Object.defineProperty(exports, "__esModule", { value: true }); exports.Principal = exports.Nat64 = exports.Nat32 = exports.Nat16 = exports.Nat8 = exports.Int64 = exports.Int32 = exports.Int16 = exports.Int8 = exports.Float64 = exports.Float32 = exports.Nat = exports.Int = exports.Text = exports.Null = exports.Bool = exports.Unknown = exports.Reserved = exports.Empty = exports.ServiceClass = exports.FuncClass = exports.PrincipalClass = exports.RecClass = exports.VariantClass = exports.TupleClass = exports.RecordClass = exports.OptClass = exports.VecClass = exports.FixedNatClass = exports.FixedIntClass = exports.FloatClass = exports.NatClass = exports.IntClass = exports.TextClass = exports.ReservedClass = exports.NullClass = exports.BoolClass = exports.UnknownClass = exports.EmptyClass = exports.ConstructType = exports.PrimitiveType = exports.Type = exports.Visitor = void 0; exports.encode = encode; exports.decode = decode; exports.Tuple = Tuple; exports.Vec = Vec; exports.Opt = Opt; exports.Record = Record; exports.Variant = Variant; exports.Rec = Rec; exports.Func = Func; exports.Service = Service; exports.resetSubtypeCache = resetSubtypeCache; exports.subtype = subtype; /* eslint-disable @typescript-eslint/no-unused-vars */ /* eslint-disable @typescript-eslint/no-explicit-any */ const principal_1 = require("@dfinity/principal"); const buffer_ts_1 = require("./utils/buffer.js"); const hash_ts_1 = require("./utils/hash.js"); const leb128_ts_1 = require("./utils/leb128.js"); const bigint_math_ts_1 = require("./utils/bigint-math.js"); /** * This module provides a combinator library to create serializers/deserializers * between JavaScript values and IDL used by canisters on the Internet Computer, * as documented at https://github.com/dfinity/candid/blob/119703ba342d2fef6ab4972d2541b9fe36ae8e36/spec/Candid.md */ var IDLTypeIds; (function (IDLTypeIds) { IDLTypeIds[IDLTypeIds["Null"] = -1] = "Null"; IDLTypeIds[IDLTypeIds["Bool"] = -2] = "Bool"; IDLTypeIds[IDLTypeIds["Nat"] = -3] = "Nat"; IDLTypeIds[IDLTypeIds["Int"] = -4] = "Int"; IDLTypeIds[IDLTypeIds["Float32"] = -13] = "Float32"; IDLTypeIds[IDLTypeIds["Float64"] = -14] = "Float64"; IDLTypeIds[IDLTypeIds["Text"] = -15] = "Text"; IDLTypeIds[IDLTypeIds["Reserved"] = -16] = "Reserved"; IDLTypeIds[IDLTypeIds["Empty"] = -17] = "Empty"; IDLTypeIds[IDLTypeIds["Opt"] = -18] = "Opt"; IDLTypeIds[IDLTypeIds["Vector"] = -19] = "Vector"; IDLTypeIds[IDLTypeIds["Record"] = -20] = "Record"; IDLTypeIds[IDLTypeIds["Variant"] = -21] = "Variant"; IDLTypeIds[IDLTypeIds["Func"] = -22] = "Func"; IDLTypeIds[IDLTypeIds["Service"] = -23] = "Service"; IDLTypeIds[IDLTypeIds["Principal"] = -24] = "Principal"; })(IDLTypeIds || (IDLTypeIds = {})); const magicNumber = 'DIDL'; const toReadableString_max = 400; // will not display arguments after 400chars. Makes sure 2mb blobs don't get inside the error function zipWith(xs, ys, f) { return xs.map((x, i) => f(x, ys[i])); } /** * An IDL Type Table, which precedes the data in the stream. */ class TypeTable { constructor() { // List of types. Needs to be an array as the index needs to be stable. this._typs = []; this._idx = new Map(); this._idxRefCount = new Map(); } has(obj) { return this._idx.has(obj.name); } add(type, buf) { const idx = this._typs.length; this._idx.set(type.name, idx); this._idxRefCount.set(idx, 1); this._typs.push(buf); } merge(obj, knot) { const idx = this._idx.get(obj.name); const knotIdx = this._idx.get(knot); if (idx === undefined) { throw new Error('Missing type index for ' + obj); } if (knotIdx === undefined) { throw new Error('Missing type index for ' + knot); } // Point the recursive placeholder (obj) to the concrete type bytes this._typs[idx] = this._typs[knotIdx]; // Merge mappings so BOTH names point to the same index // This avoids losing lookups for the concrete type name (e.g. "opt nat8") // which may still be referenced elsewhere in the type table build. const idxRefCount = this._getIdxRefCount(idx); const knotRefCount = this._getIdxRefCount(knotIdx); this._idxRefCount.set(idx, idxRefCount + knotRefCount); // Re-point the knot name to the resolved index and mark the old index as unused this._idx.set(knot, idx); this._idxRefCount.set(knotIdx, 0); // Remove unused trailing entries if possible this._compactFromEnd(); } _getIdxRefCount(idx) { return this._idxRefCount.get(idx) || 0; } _compactFromEnd() { // Remove unused entries from the end of the array while (this._typs.length > 0) { const lastIndex = this._typs.length - 1; if (this._getIdxRefCount(lastIndex) > 0) { break; } this._typs.pop(); this._idxRefCount.delete(lastIndex); } } encode() { const len = (0, leb128_ts_1.lebEncode)(this._typs.length); const buf = (0, buffer_ts_1.concat)(...this._typs); return (0, buffer_ts_1.concat)(len, buf); } indexOf(typeName) { if (!this._idx.has(typeName)) { throw new Error('Missing type index for ' + typeName); } return (0, leb128_ts_1.slebEncode)(this._idx.get(typeName) || 0); } } class Visitor { visitType(_t, _data) { throw new Error('Not implemented'); } visitPrimitive(t, data) { return this.visitType(t, data); } visitEmpty(t, data) { return this.visitPrimitive(t, data); } visitBool(t, data) { return this.visitPrimitive(t, data); } visitNull(t, data) { return this.visitPrimitive(t, data); } visitReserved(t, data) { return this.visitPrimitive(t, data); } visitText(t, data) { return this.visitPrimitive(t, data); } visitNumber(t, data) { return this.visitPrimitive(t, data); } visitInt(t, data) { return this.visitNumber(t, data); } visitNat(t, data) { return this.visitNumber(t, data); } visitFloat(t, data) { return this.visitPrimitive(t, data); } visitFixedInt(t, data) { return this.visitNumber(t, data); } visitFixedNat(t, data) { return this.visitNumber(t, data); } visitPrincipal(t, data) { return this.visitPrimitive(t, data); } visitConstruct(t, data) { return this.visitType(t, data); } visitVec(t, _ty, data) { return this.visitConstruct(t, data); } visitOpt(t, _ty, data) { return this.visitConstruct(t, data); } visitRecord(t, _fields, data) { return this.visitConstruct(t, data); } visitTuple(t, components, data) { const fields = components.map((ty, i) => [`_${i}_`, ty]); return this.visitRecord(t, fields, data); } visitVariant(t, _fields, data) { return this.visitConstruct(t, data); } visitRec(_t, ty, data) { return this.visitConstruct(ty, data); } visitFunc(t, data) { return this.visitConstruct(t, data); } visitService(t, data) { return this.visitConstruct(t, data); } } exports.Visitor = Visitor; // We try to use hard-to-accidentally-pick names to avoid potential collisions with other types. var IdlTypeName; (function (IdlTypeName) { IdlTypeName["EmptyClass"] = "__IDL_EmptyClass__"; IdlTypeName["UnknownClass"] = "__IDL_UnknownClass__"; IdlTypeName["BoolClass"] = "__IDL_BoolClass__"; IdlTypeName["NullClass"] = "__IDL_NullClass__"; IdlTypeName["ReservedClass"] = "__IDL_ReservedClass__"; IdlTypeName["TextClass"] = "__IDL_TextClass__"; IdlTypeName["IntClass"] = "__IDL_IntClass__"; IdlTypeName["NatClass"] = "__IDL_NatClass__"; IdlTypeName["FloatClass"] = "__IDL_FloatClass__"; IdlTypeName["FixedIntClass"] = "__IDL_FixedIntClass__"; IdlTypeName["FixedNatClass"] = "__IDL_FixedNatClass__"; IdlTypeName["VecClass"] = "__IDL_VecClass__"; IdlTypeName["OptClass"] = "__IDL_OptClass__"; IdlTypeName["RecordClass"] = "__IDL_RecordClass__"; IdlTypeName["TupleClass"] = "__IDL_TupleClass__"; IdlTypeName["VariantClass"] = "__IDL_VariantClass__"; IdlTypeName["RecClass"] = "__IDL_RecClass__"; IdlTypeName["PrincipalClass"] = "__IDL_PrincipalClass__"; IdlTypeName["FuncClass"] = "__IDL_FuncClass__"; IdlTypeName["ServiceClass"] = "__IDL_ServiceClass__"; })(IdlTypeName || (IdlTypeName = {})); /** * Represents an IDL type. */ class Type { /* Display type name */ display() { return this.name; } valueToString(x) { return toReadableString(x); } /* Implement `T` in the IDL spec, only needed for non-primitive types */ buildTypeTable(typeTable) { if (!typeTable.has(this)) { this._buildTypeTableImpl(typeTable); } } } exports.Type = Type; class PrimitiveType extends Type { checkType(t) { if (this.name !== t.name) { throw new Error(`type mismatch: type on the wire ${t.name}, expect type ${this.name}`); } return t; } _buildTypeTableImpl(_typeTable) { // No type table encoding for Primitive types. return; } } exports.PrimitiveType = PrimitiveType; class ConstructType extends Type { checkType(t) { if (t instanceof RecClass) { const ty = t.getType(); if (typeof ty === 'undefined') { throw new Error('type mismatch with uninitialized type'); } return ty; } throw new Error(`type mismatch: type on the wire ${t.name}, expect type ${this.name}`); } encodeType(typeTable) { return typeTable.indexOf(this.name); } } exports.ConstructType = ConstructType; /** * Represents an IDL Empty, a type which has no inhabitants. * Since no values exist for this type, it cannot be serialised or deserialised. * Result types like `Result<Text, Empty>` should always succeed. */ class EmptyClass extends PrimitiveType { get typeName() { return IdlTypeName.EmptyClass; } static [Symbol.hasInstance](instance) { return instance.typeName === IdlTypeName.EmptyClass; } accept(v, d) { return v.visitEmpty(this, d); } covariant(x) { throw new Error(`Invalid ${this.display()} argument: ${toReadableString(x)}`); } encodeValue() { throw new Error('Empty cannot appear as a function argument'); } valueToString() { throw new Error('Empty cannot appear as a value'); } encodeType() { return (0, leb128_ts_1.slebEncode)(IDLTypeIds.Empty); } decodeValue() { throw new Error('Empty cannot appear as an output'); } get name() { return 'empty'; } } exports.EmptyClass = EmptyClass; /** * Represents an IDL Unknown, a placeholder type for deserialization only. * When decoding a value as Unknown, all fields will be retained but the names are only available in * hashed form. * A deserialized unknown will offer it's actual type by calling the `type()` function. * Unknown cannot be serialized and attempting to do so will throw an error. */ class UnknownClass extends Type { get typeName() { return IdlTypeName.UnknownClass; } static [Symbol.hasInstance](instance) { return instance.typeName === IdlTypeName.UnknownClass; } checkType(_t) { throw new Error('Method not implemented for unknown.'); } accept(v, d) { throw v.visitType(this, d); } covariant(x) { throw new Error(`Invalid ${this.display()} argument: ${toReadableString(x)}`); } encodeValue() { throw new Error('Unknown cannot appear as a function argument'); } valueToString() { throw new Error('Unknown cannot appear as a value'); } encodeType() { throw new Error('Unknown cannot be serialized'); } decodeValue(b, t) { let decodedValue = t.decodeValue(b, t); if (Object(decodedValue) !== decodedValue) { // decodedValue is primitive. Box it, otherwise we cannot add the type() function. // The type() function is important for primitives because otherwise we cannot tell apart the // different number types. decodedValue = Object(decodedValue); } let typeFunc; if (t instanceof RecClass) { typeFunc = () => t.getType(); } else { typeFunc = () => t; } // Do not use 'decodedValue.type = typeFunc' because this would lead to an enumerable property // 'type' which means it would be serialized if the value would be candid encoded again. // This in turn leads to problems if the decoded value is a variant because these values are // only allowed to have a single property. Object.defineProperty(decodedValue, 'type', { value: typeFunc, writable: true, enumerable: false, configurable: true, }); return decodedValue; } _buildTypeTableImpl() { throw new Error('Unknown cannot be serialized'); } get name() { return 'Unknown'; } } exports.UnknownClass = UnknownClass; /** * Represents an IDL Bool */ class BoolClass extends PrimitiveType { get typeName() { return IdlTypeName.BoolClass; } static [Symbol.hasInstance](instance) { return instance.typeName === IdlTypeName.BoolClass; } accept(v, d) { return v.visitBool(this, d); } covariant(x) { if (typeof x === 'boolean') return true; throw new Error(`Invalid ${this.display()} argument: ${toReadableString(x)}`); } encodeValue(x) { return new Uint8Array([x ? 1 : 0]); } encodeType() { return (0, leb128_ts_1.slebEncode)(IDLTypeIds.Bool); } decodeValue(b, t) { this.checkType(t); switch ((0, leb128_ts_1.safeReadUint8)(b)) { case 0: return false; case 1: return true; default: throw new Error('Boolean value out of range'); } } get name() { return 'bool'; } } exports.BoolClass = BoolClass; /** * Represents an IDL Null */ class NullClass extends PrimitiveType { get typeName() { return IdlTypeName.NullClass; } static [Symbol.hasInstance](instance) { return instance.typeName === IdlTypeName.NullClass; } accept(v, d) { return v.visitNull(this, d); } covariant(x) { if (x === null) return true; throw new Error(`Invalid ${this.display()} argument: ${toReadableString(x)}`); } encodeValue() { return new Uint8Array(0); } encodeType() { return (0, leb128_ts_1.slebEncode)(IDLTypeIds.Null); } decodeValue(_b, t) { this.checkType(t); return null; } get name() { return 'null'; } } exports.NullClass = NullClass; /** * Represents an IDL Reserved */ class ReservedClass extends PrimitiveType { get typeName() { return IdlTypeName.ReservedClass; } static [Symbol.hasInstance](instance) { return instance.typeName === IdlTypeName.ReservedClass; } accept(v, d) { return v.visitReserved(this, d); } covariant(_x) { return true; } encodeValue() { return new Uint8Array(0); } encodeType() { return (0, leb128_ts_1.slebEncode)(IDLTypeIds.Reserved); } decodeValue(b, t) { if (t.name !== this.name) { t.decodeValue(b, t); } return null; } get name() { return 'reserved'; } } exports.ReservedClass = ReservedClass; /** * Represents an IDL Text */ class TextClass extends PrimitiveType { get typeName() { return IdlTypeName.TextClass; } static [Symbol.hasInstance](instance) { return instance.typeName === IdlTypeName.TextClass; } accept(v, d) { return v.visitText(this, d); } covariant(x) { if (typeof x === 'string') return true; throw new Error(`Invalid ${this.display()} argument: ${toReadableString(x)}`); } encodeValue(x) { const buf = new TextEncoder().encode(x); const len = (0, leb128_ts_1.lebEncode)(buf.byteLength); return (0, buffer_ts_1.concat)(len, buf); } encodeType() { return (0, leb128_ts_1.slebEncode)(IDLTypeIds.Text); } decodeValue(b, t) { this.checkType(t); const len = (0, leb128_ts_1.lebDecode)(b); const buf = (0, leb128_ts_1.safeRead)(b, Number(len)); const decoder = new TextDecoder('utf8', { fatal: true }); return decoder.decode(buf); } get name() { return 'text'; } valueToString(x) { return '"' + x + '"'; } } exports.TextClass = TextClass; /** * Represents an IDL Int */ class IntClass extends PrimitiveType { get typeName() { return IdlTypeName.IntClass; } static [Symbol.hasInstance](instance) { return instance.typeName === IdlTypeName.IntClass; } accept(v, d) { return v.visitInt(this, d); } covariant(x) { // We allow encoding of JavaScript plain numbers. // But we will always decode to bigint. if (typeof x === 'bigint' || Number.isInteger(x)) return true; throw new Error(`Invalid ${this.display()} argument: ${toReadableString(x)}`); } encodeValue(x) { return (0, leb128_ts_1.slebEncode)(x); } encodeType() { return (0, leb128_ts_1.slebEncode)(IDLTypeIds.Int); } decodeValue(b, t) { this.checkType(t); return (0, leb128_ts_1.slebDecode)(b); } get name() { return 'int'; } valueToString(x) { return x.toString(); } } exports.IntClass = IntClass; /** * Represents an IDL Nat */ class NatClass extends PrimitiveType { get typeName() { return IdlTypeName.NatClass; } static [Symbol.hasInstance](instance) { return instance.typeName === IdlTypeName.NatClass; } accept(v, d) { return v.visitNat(this, d); } covariant(x) { // We allow encoding of JavaScript plain numbers. // But we will always decode to bigint. if ((typeof x === 'bigint' && x >= BigInt(0)) || (Number.isInteger(x) && x >= 0)) return true; throw new Error(`Invalid ${this.display()} argument: ${toReadableString(x)}`); } encodeValue(x) { return (0, leb128_ts_1.lebEncode)(x); } encodeType() { return (0, leb128_ts_1.slebEncode)(IDLTypeIds.Nat); } decodeValue(b, t) { this.checkType(t); return (0, leb128_ts_1.lebDecode)(b); } get name() { return 'nat'; } valueToString(x) { return x.toString(); } } exports.NatClass = NatClass; /** * Represents an IDL Float */ class FloatClass extends PrimitiveType { get typeName() { return IdlTypeName.FloatClass; } static [Symbol.hasInstance](instance) { return instance.typeName === IdlTypeName.FloatClass; } constructor(_bits) { super(); this._bits = _bits; if (_bits !== 32 && _bits !== 64) { throw new Error('not a valid float type'); } } accept(v, d) { return v.visitFloat(this, d); } covariant(x) { if (typeof x === 'number' || x instanceof Number) return true; throw new Error(`Invalid ${this.display()} argument: ${toReadableString(x)}`); } encodeValue(x) { const buf = new ArrayBuffer(this._bits / 8); const view = new DataView(buf); if (this._bits === 32) { view.setFloat32(0, x, true); } else { view.setFloat64(0, x, true); } return new Uint8Array(buf); } encodeType() { const opcode = this._bits === 32 ? IDLTypeIds.Float32 : IDLTypeIds.Float64; return (0, leb128_ts_1.slebEncode)(opcode); } decodeValue(b, t) { this.checkType(t); const bytes = (0, leb128_ts_1.safeRead)(b, this._bits / 8); const view = (0, buffer_ts_1.uint8ToDataView)(bytes); if (this._bits === 32) { return view.getFloat32(0, true); } else { return view.getFloat64(0, true); } } get name() { return 'float' + this._bits; } valueToString(x) { return x.toString(); } } exports.FloatClass = FloatClass; /** * Represents an IDL fixed-width Int(n) */ class FixedIntClass extends PrimitiveType { get typeName() { return IdlTypeName.FixedIntClass; } static [Symbol.hasInstance](instance) { return instance.typeName === IdlTypeName.FixedIntClass; } constructor(_bits) { super(); this._bits = _bits; } accept(v, d) { return v.visitFixedInt(this, d); } covariant(x) { const min = (0, bigint_math_ts_1.iexp2)(this._bits - 1) * BigInt(-1); const max = (0, bigint_math_ts_1.iexp2)(this._bits - 1) - BigInt(1); let ok = false; if (typeof x === 'bigint') { ok = x >= min && x <= max; } else if (Number.isInteger(x)) { const v = BigInt(x); ok = v >= min && v <= max; } else { ok = false; } if (ok) return true; throw new Error(`Invalid ${this.display()} argument: ${toReadableString(x)}`); } encodeValue(x) { return (0, leb128_ts_1.writeIntLE)(x, this._bits / 8); } encodeType() { const offset = Math.log2(this._bits) - 3; return (0, leb128_ts_1.slebEncode)(-9 - offset); } decodeValue(b, t) { this.checkType(t); const num = (0, leb128_ts_1.readIntLE)(b, this._bits / 8); if (this._bits <= 32) { return Number(num); } else { return num; } } get name() { return `int${this._bits}`; } valueToString(x) { return x.toString(); } } exports.FixedIntClass = FixedIntClass; /** * Represents an IDL fixed-width Nat(n) */ class FixedNatClass extends PrimitiveType { get typeName() { return IdlTypeName.FixedNatClass; } static [Symbol.hasInstance](instance) { return instance.typeName === IdlTypeName.FixedNatClass; } constructor(_bits) { super(); this._bits = _bits; } accept(v, d) { return v.visitFixedNat(this, d); } covariant(x) { const max = (0, bigint_math_ts_1.iexp2)(this._bits); let ok = false; if (typeof x === 'bigint' && x >= BigInt(0)) { ok = x < max; } else if (Number.isInteger(x) && x >= 0) { const v = BigInt(x); ok = v < max; } else { ok = false; } if (ok) return true; throw new Error(`Invalid ${this.display()} argument: ${toReadableString(x)}`); } encodeValue(x) { return (0, leb128_ts_1.writeUIntLE)(x, this._bits / 8); } encodeType() { const offset = Math.log2(this._bits) - 3; return (0, leb128_ts_1.slebEncode)(-5 - offset); } decodeValue(b, t) { this.checkType(t); const num = (0, leb128_ts_1.readUIntLE)(b, this._bits / 8); if (this._bits <= 32) { return Number(num); } else { return num; } } get name() { return `nat${this._bits}`; } valueToString(x) { return x.toString(); } } exports.FixedNatClass = FixedNatClass; /** * Represents an IDL Array * * Arrays of fixed-sized nat/int type (e.g. nat8), are encoded from and decoded to TypedArrays (e.g. Uint8Array). * Arrays of float or other non-primitive types are encoded/decoded as untyped array in Javascript. * @param {Type} t */ class VecClass extends ConstructType { get typeName() { return IdlTypeName.VecClass; } static [Symbol.hasInstance](instance) { return instance.typeName === IdlTypeName.VecClass; } constructor(_type) { super(); this._type = _type; // If true, this vector is really a blob and we can just use memcpy. // // NOTE: // With support of encoding/dencoding of TypedArrays, this optimization is // only used when plain array of bytes are passed as encoding input in order // to be backward compatible. this._blobOptimization = false; if (_type instanceof FixedNatClass && _type._bits === 8) { this._blobOptimization = true; } } accept(v, d) { return v.visitVec(this, this._type, d); } covariant(x) { // Special case for ArrayBuffer const bits = this._type instanceof FixedNatClass ? this._type._bits : this._type instanceof FixedIntClass ? this._type._bits : 0; if ((ArrayBuffer.isView(x) && bits == x.BYTES_PER_ELEMENT * 8) || (Array.isArray(x) && x.every((v, idx) => { try { return this._type.covariant(v); } catch (e) { throw new Error(`Invalid ${this.display()} argument: \n\nindex ${idx} -> ${e.message}`); } }))) return true; throw new Error(`Invalid ${this.display()} argument: ${toReadableString(x)}`); } encodeValue(x) { const len = (0, leb128_ts_1.lebEncode)(x.length); if (this._blobOptimization) { return (0, buffer_ts_1.concat)(len, new Uint8Array(x)); } if (ArrayBuffer.isView(x)) { // Handle TypedArrays with endianness concerns if (x instanceof Int16Array || x instanceof Uint16Array) { const buffer = new DataView(new ArrayBuffer(x.length * 2)); for (let i = 0; i < x.length; i++) { if (x instanceof Int16Array) { buffer.setInt16(i * 2, x[i], true); // true = little-endian } else { buffer.setUint16(i * 2, x[i], true); } } return (0, buffer_ts_1.concat)(len, new Uint8Array(buffer.buffer)); } else if (x instanceof Int32Array || x instanceof Uint32Array) { const buffer = new DataView(new ArrayBuffer(x.length * 4)); for (let i = 0; i < x.length; i++) { if (x instanceof Int32Array) { buffer.setInt32(i * 4, x[i], true); } else { buffer.setUint32(i * 4, x[i], true); } } return (0, buffer_ts_1.concat)(len, new Uint8Array(buffer.buffer)); } else if (x instanceof BigInt64Array || x instanceof BigUint64Array) { const buffer = new DataView(new ArrayBuffer(x.length * 8)); for (let i = 0; i < x.length; i++) { if (x instanceof BigInt64Array) { buffer.setBigInt64(i * 8, x[i], true); } else { buffer.setBigUint64(i * 8, x[i], true); } } return (0, buffer_ts_1.concat)(len, new Uint8Array(buffer.buffer)); } else { // For Uint8Array, Int8Array, etc. that don't have endianness concerns return (0, buffer_ts_1.concat)(len, new Uint8Array(x.buffer, x.byteOffset, x.byteLength)); } } const buf = new buffer_ts_1.PipeArrayBuffer(new Uint8Array(len.byteLength + x.length), 0); buf.write(len); for (const d of x) { const encoded = this._type.encodeValue(d); buf.write(new Uint8Array(encoded)); } return buf.buffer; } _buildTypeTableImpl(typeTable) { this._type.buildTypeTable(typeTable); const opCode = (0, leb128_ts_1.slebEncode)(IDLTypeIds.Vector); const buffer = this._type.encodeType(typeTable); typeTable.add(this, (0, buffer_ts_1.concat)(opCode, buffer)); } decodeValue(b, t) { const vec = this.checkType(t); if (!(vec instanceof VecClass)) { throw new Error('Not a vector type'); } const len = Number((0, leb128_ts_1.lebDecode)(b)); if (this._type instanceof FixedNatClass) { if (this._type._bits == 8) { return new Uint8Array(b.read(len)); } if (this._type._bits == 16) { const bytes = b.read(len * 2); // Check if we need to swap bytes for endianness const u16 = new Uint16Array(bytes.buffer, bytes.byteOffset, len); return u16; } if (this._type._bits == 32) { const bytes = b.read(len * 4); const u32 = new Uint32Array(bytes.buffer, bytes.byteOffset, len); return u32; } if (this._type._bits == 64) { return new BigUint64Array(b.read(len * 8).buffer); } } if (this._type instanceof FixedIntClass) { if (this._type._bits == 8) { return new Int8Array(b.read(len)); } if (this._type._bits == 16) { const bytes = b.read(len * 2); // Create a DataView to properly handle endianness const view = new DataView(bytes.buffer, bytes.byteOffset, bytes.byteLength); // Create result array with correct endianness const result = new Int16Array(len); for (let i = 0; i < len; i++) { // Read each value as little-endian (Candid wire format is little-endian) result[i] = view.getInt16(i * 2, true); } return result; } if (this._type._bits == 32) { const bytes = b.read(len * 4); const view = new DataView(bytes.buffer, bytes.byteOffset, bytes.byteLength); const result = new Int32Array(len); for (let i = 0; i < len; i++) { result[i] = view.getInt32(i * 4, true); } return result; } if (this._type._bits == 64) { const bytes = b.read(len * 8); const view = new DataView(bytes.buffer, bytes.byteOffset, bytes.byteLength); const result = new BigInt64Array(len); for (let i = 0; i < len; i++) { result[i] = view.getBigInt64(i * 8, true); } return result; } } const rets = []; for (let i = 0; i < len; i++) { rets.push(this._type.decodeValue(b, vec._type)); } return rets; } get name() { return `vec ${this._type.name}`; } display() { return `vec ${this._type.display()}`; } valueToString(x) { const elements = x.map(e => this._type.valueToString(e)); return 'vec {' + elements.join('; ') + '}'; } } exports.VecClass = VecClass; /** * Represents an IDL Option * @param {Type} t */ class OptClass extends ConstructType { get typeName() { return IdlTypeName.OptClass; } static [Symbol.hasInstance](instance) { return instance.typeName === IdlTypeName.OptClass; } constructor(_type) { super(); this._type = _type; } accept(v, d) { return v.visitOpt(this, this._type, d); } covariant(x) { try { if (Array.isArray(x) && (x.length === 0 || (x.length === 1 && this._type.covariant(x[0])))) return true; } catch (e) { throw new Error(`Invalid ${this.display()} argument: ${toReadableString(x)} \n\n-> ${e.message}`); } throw new Error(`Invalid ${this.display()} argument: ${toReadableString(x)}`); } encodeValue(x) { if (x.length === 0) { return new Uint8Array([0]); } else { return (0, buffer_ts_1.concat)(new Uint8Array([1]), this._type.encodeValue(x[0])); } } _buildTypeTableImpl(typeTable) { this._type.buildTypeTable(typeTable); const opCode = (0, leb128_ts_1.slebEncode)(IDLTypeIds.Opt); const buffer = this._type.encodeType(typeTable); typeTable.add(this, (0, buffer_ts_1.concat)(opCode, buffer)); } decodeValue(b, t) { if (t instanceof NullClass) { return []; } if (t instanceof ReservedClass) { return []; } let wireType = t; // unfold wireType, if needed if (t instanceof RecClass) { const ty = t.getType(); if (typeof ty === 'undefined') { throw new Error('type mismatch with uninitialized type'); } else wireType = ty; } if (wireType instanceof OptClass) { switch ((0, leb128_ts_1.safeReadUint8)(b)) { case 0: return []; case 1: { // Save the current state of the Pipe `b` to allow rollback in case of an error const checkpoint = b.save(); try { // Attempt to decode a value using the `_type` of the current instance const v = this._type.decodeValue(b, wireType._type); return [v]; } catch (e) { // If an error occurs during decoding, restore the Pipe `b` to its previous state b.restore(checkpoint); // Skip the value at the current wire type to advance the Pipe `b` position wireType._type.decodeValue(b, wireType._type); // Return an empty array to indicate a `none` value return []; } } default: throw new Error('Not an option value'); } } else if ( // this check corresponds to `not (null <: <t>)` in the spec this._type instanceof NullClass || this._type instanceof OptClass || this._type instanceof ReservedClass) { // null <: <t> : // skip value at wire type (to advance b) and return "null", i.e. [] wireType.decodeValue(b, wireType); return []; } else { // not (null <: t) : // try constituent type const checkpoint = b.save(); try { const v = this._type.decodeValue(b, t); return [v]; } catch (e) { // decoding failed, but this is opt, so return "null", i.e. [] b.restore(checkpoint); // skip value at wire type (to advance b) wireType.decodeValue(b, t); // return "null" return []; } } } get name() { return `opt ${this._type.name}`; } display() { return `opt ${this._type.display()}`; } valueToString(x) { if (x.length === 0) { return 'null'; } else { return `opt ${this._type.valueToString(x[0])}`; } } } exports.OptClass = OptClass; /** * Represents an IDL Record * @param {object} [fields] - mapping of function name to Type */ class RecordClass extends ConstructType { get typeName() { return IdlTypeName.RecordClass; } static [Symbol.hasInstance](instance) { // TupleClass extends RecordClass, so we need to check both here return (instance.typeName === IdlTypeName.RecordClass || instance.typeName === IdlTypeName.TupleClass); } constructor(fields = {}) { super(); this._fields = Object.entries(fields).sort((a, b) => (0, hash_ts_1.idlLabelToId)(a[0]) - (0, hash_ts_1.idlLabelToId)(b[0])); } accept(v, d) { return v.visitRecord(this, this._fields, d); } tryAsTuple() { const res = []; for (let i = 0; i < this._fields.length; i++) { const [key, type] = this._fields[i]; if (key !== `_${i}_`) { return null; } res.push(type); } return res; } covariant(x) { if (typeof x === 'object' && this._fields.every(([k, t]) => { // eslint-disable-next-line if (!x.hasOwnProperty(k)) { throw new Error(`Record is missing key "${k}".`); } try { return t.covariant(x[k]); } catch (e) { throw new Error(`Invalid ${this.display()} argument: \n\nfield ${k} -> ${e.message}`); } })) return true; throw new Error(`Invalid ${this.display()} argument: ${toReadableString(x)}`); } encodeValue(x) { const values = this._fields.map(([key]) => x[key]); const bufs = zipWith(this._fields, values, ([, c], d) => c.encodeValue(d)); return (0, buffer_ts_1.concat)(...bufs); } _buildTypeTableImpl(T) { this._fields.forEach(([_, value]) => value.buildTypeTable(T)); const opCode = (0, leb128_ts_1.slebEncode)(IDLTypeIds.Record); const len = (0, leb128_ts_1.lebEncode)(this._fields.length); const fields = this._fields.map(([key, value]) => (0, buffer_ts_1.concat)((0, leb128_ts_1.lebEncode)((0, hash_ts_1.idlLabelToId)(key)), value.encodeType(T))); T.add(this, (0, buffer_ts_1.concat)(opCode, len, (0, buffer_ts_1.concat)(...fields))); } decodeValue(b, t) { const record = this.checkType(t); if (!(record instanceof RecordClass)) { throw new Error('Not a record type'); } const x = {}; let expectedRecordIdx = 0; let actualRecordIdx = 0; while (actualRecordIdx < record._fields.length) { const [hash, type] = record._fields[actualRecordIdx]; if (expectedRecordIdx >= this._fields.length) { // skip unexpected left over fields present on the wire type.decodeValue(b, type); actualRecordIdx++; continue; } const [expectKey, expectType] = this._fields[expectedRecordIdx]; const expectedId = (0, hash_ts_1.idlLabelToId)(this._fields[expectedRecordIdx][0]); const actualId = (0, hash_ts_1.idlLabelToId)(hash); if (expectedId === actualId) { // the current field on the wire matches the expected field x[expectKey] = expectType.decodeValue(b, type); expectedRecordIdx++; actualRecordIdx++; } else if (actualId > expectedId) { // The expected field does not exist on the wire if (expectType instanceof OptClass || expectType instanceof ReservedClass) { x[expectKey] = []; expectedRecordIdx++; } else { throw new Error('Cannot find required field ' + expectKey); } } else { // The field on the wire does not exist in the output type, so we can skip it type.decodeValue(b, type); actualRecordIdx++; } } // initialize left over expected optional fields for (const [expectKey, expectType] of this._fields.slice(expectedRecordIdx)) { if (expectType instanceof OptClass || expectType instanceof ReservedClass) { // TODO this assumes null value in opt is represented as [] x[expectKey] = []; } else { throw new Error('Cannot find required field ' + expectKey); } } return x; } get fieldsAsObject() { const fields = {}; for (const [name, ty] of this._fields) { fields[(0, hash_ts_1.idlLabelToId)(name)] = ty; } return fields; } get name() { const fields = this._fields.map(([key, value]) => key + ':' + value.name); return `record {${fields.join('; ')}}`; } display() { const fields = this._fields.map(([key, value]) => key + ':' + value.display()); return `record {${fields.join('; ')}}`; } valueToString(x) { const values = this._fields.map(([key]) => x[key]); const fields = zipWith(this._fields, values, ([k, c], d) => k + '=' + c.valueToString(d)); return `record {${fields.join('; ')}}`; } } exports.RecordClass = RecordClass; /** * Represents Tuple, a syntactic sugar for Record. * @param {Type} components */ class TupleClass extends RecordClass { get typeName() { return IdlTypeName.TupleClass; } static [Symbol.hasInstance](instance) { return instance.typeName === IdlTypeName.TupleClass; } constructor(_components) { const x = {}; _components.forEach((e, i) => (x['_' + i + '_'] = e)); super(x); this._components = _components; } accept(v, d) { return v.visitTuple(this, this._components, d); } covariant(x) { // `>=` because tuples can be covariant when encoded. if (Array.isArray(x) && x.length >= this._fields.length && this._components.every((t, i) => { try { return t.covariant(x[i]); } catch (e) { throw new Error(`Invalid ${this.display()} argument: \n\nindex ${i} -> ${e.message}`); } })) return true; throw new Error(`Invalid ${this.display()} argument: ${toReadableString(x)}`); } encodeValue(x) { const bufs = zipWith(this._components, x, (c, d) => c.encodeValue(d)); return (0, buffer_ts_1.concat)(...bufs); } decodeValue(b, t) { const tuple = this.checkType(t); if (!(tuple instanceof TupleClass)) { throw new Error('not a tuple type'); } if (tuple._components.length < this._components.length) { throw new Error('tuple mismatch'); } const res = []; for (const [i, wireType] of tuple._components.entries()) { if (i >= this._components.length) { // skip value wireType.decodeValue(b, wireType); } else { res.push(this._components[i].decodeValue(b, wireType)); } } return res; } display() { const fields = this._components.map(value => value.display()); return `record {${fields.join('; ')}}`; } valueToString(values) { const fields = zipWith(this._components, values, (c, d) => c.valueToString(d)); return `record {${fields.join('; ')}}`; } } exports.TupleClass = TupleClass; /** * Represents an IDL Variant * @param {object} [fields] - mapping of function name to Type */ class VariantClass extends ConstructType { get typeName() { return IdlTypeName.VariantClass; } static [Symbol.hasInstance](instance) { return instance.typeName === IdlTypeName.VariantClass; } constructor(fields = {}) { super(); this._fields = Object.entries(fields).sort((a, b) => (0, hash_ts_1.idlLabelToId)(a[0]) - (0, hash_ts_1.idlLabelToId)(b[0])); } accept(v, d) { return v.visitVariant(this, this._fields, d); } covariant(x) { if (typeof x === 'object' && Object.entries(x).length === 1 && this._fields.every(([k, v]) => { try { // eslint-disable-next-line return !x.hasOwnProperty(k) || v.covariant(x[k]); } catch (e) { throw new Error(`Invalid ${this.display()} argument: \n\nvariant ${k} -> ${e.message}`); } })) return true; throw new Error(`Invalid ${this.display()} argument: ${toReadableString(x)}`); } encodeValue(x) { for (let i = 0; i < this._fields.length; i++) { const [name, type] = this._fields[i]; // eslint-disable-next-line if (x.hasOwnProperty(name)) { const idx = (0, leb128_ts_1.lebEncode)(i); const buf = type.encodeValue(x[name]); return (0, buffer_ts_1.concat)(idx, buf); } } throw Error('Variant has no data: ' + x); } _buildTypeTableImpl(typeTable) { this._fields.forEach(([, type]) => { type.buildTypeTable(typeTable); }); const opCode = (0, leb128_ts_1.slebEncode)(IDLTypeIds.Variant); const len = (0, leb128_ts_1.lebEncode)(this._fields.length); const fields = this._fields.map(([key, value]) => (0, buffer_ts_1.concat)((0, leb128_ts_1.lebEncode)((0, hash_ts_1.idlLabelToId)(key)), value.encodeType(typeTable))); typeTable.add(this, (0, buffer_ts_1.concat)(opCode, len, ...fields)); } decodeValue(b, t) { const variant = this.checkType(t); if (!(variant instanceof VariantClass)) { throw new Error('Not a variant type'); } const idx = Number((0, leb128_ts_1.lebDecode)(b)); if (idx >= variant._fields.length) { throw Error('Invalid variant index: ' + idx); } const [wireHash, wireType] = variant._fields[idx]; for (const [key, expectType] of this._fields) { if ((0, hash_ts_1.idlLabelToId)(wireHash) === (0, hash_ts_1.idlLabelToId)(key)) { const value = expectType.decodeValue(b, wireType); return { [key]: value }; } } throw new Error('Cannot find field hash ' + wireHash); } get name() { const fields = this._fields.map(([key, type]) => key + ':' + type.name); return `variant {${fields.join('; ')}}`; } display() { const fields = this._fields.map(([key, type]) => key + (type.name === 'null' ? '' : `:${type.display()}`)); return `variant {${fields.join('; ')}}`; } valueToString(x) { for (const [name, type] of this._fields) { // eslint-disable-next-line if (x.hasOwnProperty(name)) { const value = type.valueToString(x[name]); if (value === 'null') { return `variant {${name}}`; } else { return `variant {${name}=${value}}`; } } } throw new Error('Variant has no data: ' + x); } get alternativesAsObject() { const alternatives = {}; for (const [name, ty] of this._fields) { alternatives[(0, hash_ts_1.idlLabelToId)(name)] = ty; } return alternatives; } } exports.VariantClass = VariantClass; /** * Represents a reference to an IDL type, used for defining recursive data * types. */ class RecClass extends ConstructType { constructor() { super(...arguments); this._id = RecClass._counter++; } get typeName() { return IdlTypeName.RecClass; } static { this._counter = 0; } static [Symbol.hasInstance](instance) { return instance.typeName === IdlTypeName.RecClass; } accept(v, d) { if (!this._type) { throw Error('Recursive type uninitialized.'); } return v.visitRec(this, this._type, d); } fill(t) { this._type = t; } getType() { return this._type; } covariant(x) { if (this._type ? this._type.covariant(x) : false) return true; throw new Error(`Invalid ${this.display()} argument: ${toReadableString(x)}`); } encodeValue(x) { if (!this._type) { throw Error('Recursive type uninitialized.'); } return this._type.encodeValue(x); } _buildTypeTableImpl(typeTable) { if (!this._type) { throw Error('Recursive type uninitialized.'); } typeTable.add(this, new Uint8Array([])); this._type.buildTypeTable(typeTable); typeTable.merge(this, this._type.name); } decodeValue(b, t) { if (!this._type) { throw Error('Recursive type uninitialized.'); } return this._type.decodeValue(b, t); } get name() { return `rec_${this._id}`; } display() { if (!this._type) { throw Error('Recursive type uninitialized.'); } return `μ${this.name}.${this._type.name}`; } valueToString(x) { if (!this._type) { throw Error('Recursive type uninitial