couchbase
Version:
The official Couchbase Node.js Client Library.
282 lines (281 loc) • 9.44 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.RawJsonTranscoder = exports.RawStringTranscoder = exports.RawBinaryTranscoder = exports.DefaultTranscoder = void 0;
const NF_JSON = 0x00;
const NF_RAW = 0x02;
const NF_UTF8 = 0x04;
const NF_MASK = 0xff;
const NF_UNKNOWN = 0x100;
const CF_NONE = 0x00 << 24;
const CF_PRIVATE = 0x01 << 24;
const CF_JSON = 0x02 << 24;
const CF_RAW = 0x03 << 24;
const CF_UTF8 = 0x04 << 24;
const CF_MASK = 0xff << 24;
/**
* The default transcoder implements cross-sdk transcoding capabilities by
* taking advantage of the common flags specification to ensure compatibility.
* This transcoder is capable of encoding/decoding any value which is encodable
* to JSON, and additionally has special-case handling for Buffer objects.
*
* @category Key-Value
*/
class DefaultTranscoder {
/**
* Encodes the specified value, returning a buffer and flags that are
* stored to the server and later used for decoding.
*
* @param value The value to encode.
*/
encode(value) {
// If its a buffer, write that directly as raw.
if (Buffer.isBuffer(value)) {
return [value, CF_RAW | NF_RAW];
}
// If its a string, encode it as a UTF8 string.
if (typeof value === 'string') {
return [Buffer.from(value), CF_UTF8 | NF_UTF8];
}
// Encode it to JSON and save that otherwise.
return [Buffer.from(JSON.stringify(value)), CF_JSON | NF_JSON];
}
/**
* Decodes a buffer and flags tuple back to the original type of the
* document.
*
* @param bytes The bytes that were previously encoded.
* @param flags The flags associated with the data.
*/
decode(bytes, flags) {
let format = flags & NF_MASK;
const cfformat = flags & CF_MASK;
if (cfformat !== CF_NONE) {
if (cfformat === CF_JSON) {
format = NF_JSON;
}
else if (cfformat === CF_RAW) {
format = NF_RAW;
}
else if (cfformat === CF_UTF8) {
format = NF_UTF8;
}
else if (cfformat !== CF_PRIVATE) {
// Unknown CF Format! The following will force
// fallback to reporting RAW data.
format = NF_UNKNOWN;
}
}
if (format === NF_UTF8) {
return bytes.toString('utf8');
}
else if (format === NF_RAW) {
return bytes;
}
else if (format === NF_JSON) {
try {
return JSON.parse(bytes.toString('utf8'));
}
catch (e) {
// If we encounter a parse error, assume that we need
// to return bytes instead of an object.
return bytes;
}
}
// Default to returning a Buffer if all else fails.
return bytes;
}
}
exports.DefaultTranscoder = DefaultTranscoder;
/**
* The raw binary transcoder provides an explicit mechanism for storing and retrieving raw
* byte data.
*
* @category Key-Value
*/
class RawBinaryTranscoder {
/**
* Encodes the specified value, returning a buffer and flags that are
* stored to the server and later used for decoding.
*
* @param value The value to encode.
*/
encode(value) {
// If its a buffer, write that directly as raw.
if (Buffer.isBuffer(value)) {
return [value, CF_RAW | NF_RAW];
}
throw new Error('Only binary data supported by RawBinaryTranscoder.');
}
/**
* Decodes a buffer and flags tuple back to the original type of the
* document.
*
* @param bytes The bytes that were previously encoded.
* @param flags The flags associated with the data.
*/
decode(bytes, flags) {
let format = flags & NF_MASK;
const cfformat = flags & CF_MASK;
if (cfformat !== CF_NONE) {
if (cfformat === CF_JSON) {
format = NF_JSON;
}
else if (cfformat === CF_RAW) {
format = NF_RAW;
}
else if (cfformat === CF_UTF8) {
format = NF_UTF8;
}
else if (cfformat !== CF_PRIVATE) {
// Unknown CF Format! The following will force
// fallback to reporting RAW data.
format = NF_UNKNOWN;
}
}
if (format === NF_RAW) {
return bytes;
}
else if (format === NF_UTF8) {
throw new Error('String format not supported by RawBinaryTranscoder.');
}
else if (format === NF_JSON) {
throw new Error('JSON format not supported by RawBinaryTranscoder.');
}
else if (format === NF_UNKNOWN) {
throw new Error('Unknown format not supported by RawBinaryTranscoder.');
}
else {
throw new Error(`Unrecognized format provided: ${format}.`);
}
}
}
exports.RawBinaryTranscoder = RawBinaryTranscoder;
/**
* The raw string transcoder provides an explicit mechanism for storing and retrieving raw
* string data.
*
* @category Key-Value
*/
class RawStringTranscoder {
/**
* Encodes the specified value, returning a buffer and flags that are
* stored to the server and later used for decoding.
*
* @param value The value to encode.
*/
encode(value) {
// If its a string, encode it as a UTF8 string.
if (typeof value === 'string') {
return [Buffer.from(value), CF_UTF8 | NF_UTF8];
}
throw new Error('Only string data supported by RawStringTranscoder.');
}
/**
* Decodes a buffer and flags tuple back to the original type of the
* document.
*
* @param bytes The bytes that were previously encoded.
* @param flags The flags associated with the data.
*/
decode(bytes, flags) {
let format = flags & NF_MASK;
const cfformat = flags & CF_MASK;
if (cfformat !== CF_NONE) {
if (cfformat === CF_JSON) {
format = NF_JSON;
}
else if (cfformat === CF_RAW) {
format = NF_RAW;
}
else if (cfformat === CF_UTF8) {
format = NF_UTF8;
}
else if (cfformat !== CF_PRIVATE) {
// Unknown CF Format! The following will force
// fallback to reporting RAW data.
format = NF_UNKNOWN;
}
}
if (format === NF_UTF8) {
return bytes.toString('utf8');
}
else if (format === NF_RAW) {
throw new Error('Binary format not supported by RawStringTranscoder.');
}
else if (format === NF_JSON) {
throw new Error('JSON format not supported by RawStringTranscoder.');
}
else if (format === NF_UNKNOWN) {
throw new Error('Unknown format not supported by RawStringTranscoder.');
}
else {
throw new Error(`Unrecognized format provided: ${format}.`);
}
}
}
exports.RawStringTranscoder = RawStringTranscoder;
/**
* The raw JSON transcoder provides an explicit mechanism for storing and retrieving JSON data.
*
* @category Key-Value
*/
class RawJsonTranscoder {
/**
* Encodes the specified value, returning a buffer and flags that are
* stored to the server and later used for decoding.
*
* @param value The value to encode.
*/
encode(value) {
if (typeof value === 'string') {
return [Buffer.from(value), CF_JSON | NF_JSON];
}
if (Buffer.isBuffer(value)) {
return [value, CF_JSON | NF_JSON];
}
throw new Error('Only binary and string data supported by RawJsonTranscoder.');
}
/**
* Decodes a buffer and flags tuple back to the original type of the
* document.
*
* @param bytes The bytes that were previously encoded.
* @param flags The flags associated with the data.
*/
decode(bytes, flags) {
let format = flags & NF_MASK;
const cfformat = flags & CF_MASK;
if (cfformat !== CF_NONE) {
if (cfformat === CF_JSON) {
format = NF_JSON;
}
else if (cfformat === CF_RAW) {
format = NF_RAW;
}
else if (cfformat === CF_UTF8) {
format = NF_UTF8;
}
else if (cfformat !== CF_PRIVATE) {
// Unknown CF Format! The following will force
// fallback to reporting RAW data.
format = NF_UNKNOWN;
}
}
if (format === NF_UTF8) {
throw new Error('string format not supported by RawJsonTranscoder.');
}
else if (format === NF_RAW) {
throw new Error('Binary format not supported by RawJsonTranscoder.');
}
else if (format === NF_JSON) {
return bytes;
}
else if (format === NF_UNKNOWN) {
throw new Error('Unknown format not supported by RawJsonTranscoder.');
}
else {
throw new Error(`Unrecognized format provided: ${format}.`);
}
}
}
exports.RawJsonTranscoder = RawJsonTranscoder;