@stomp/stompjs/esm6/frame-impl.js

STOMP client for Javascript and Typescript

import { BYTE } from './byte.js';
/**
 * Frame class represents a STOMP frame.
 *
 * @internal
 */
export class FrameImpl {
    /**
     * Frame constructor. `command`, `headers` and `body` are available as properties.
     *
     * @internal
     */
    constructor(params) {
        const { command, headers, body, binaryBody, escapeHeaderValues, skipContentLengthHeader, } = params;
        this.command = command;
        this.headers = Object.assign({}, headers || {});
        if (binaryBody) {
            this._binaryBody = binaryBody;
            this.isBinaryBody = true;
        }
        else {
            this._body = body || '';
            this.isBinaryBody = false;
        }
        this.escapeHeaderValues = escapeHeaderValues || false;
        this.skipContentLengthHeader = skipContentLengthHeader || false;
    }
    /**
     * body of the frame
     */
    get body() {
        if (!this._body && this.isBinaryBody) {
            this._body = new TextDecoder().decode(this._binaryBody);
        }
        return this._body || '';
    }
    /**
     * body as Uint8Array
     */
    get binaryBody() {
        if (!this._binaryBody && !this.isBinaryBody) {
            this._binaryBody = new TextEncoder().encode(this._body);
        }
        // At this stage it will definitely have a valid value
        return this._binaryBody;
    }
    /**
     * deserialize a STOMP Frame from raw data.
     *
     * @internal
     */
    static fromRawFrame(rawFrame, escapeHeaderValues) {
        const headers = {};
        const trim = (str) => str.replace(/^\s+|\s+$/g, '');
        // In case of repeated headers, as per standards, first value need to be used
        for (const header of rawFrame.headers.reverse()) {
            const idx = header.indexOf(':');
            const key = trim(header[0]);
            let value = trim(header[1]);
            if (escapeHeaderValues &&
                rawFrame.command !== 'CONNECT' &&
                rawFrame.command !== 'CONNECTED') {
                value = FrameImpl.hdrValueUnEscape(value);
            }
            headers[key] = value;
        }
        return new FrameImpl({
            command: rawFrame.command,
            headers,
            binaryBody: rawFrame.binaryBody,
            escapeHeaderValues,
        });
    }
    /**
     * @internal
     */
    toString() {
        return this.serializeCmdAndHeaders();
    }
    /**
     * serialize this Frame in a format suitable to be passed to WebSocket.
     * If the body is string the output will be string.
     * If the body is binary (i.e. of type Unit8Array) it will be serialized to ArrayBuffer.
     *
     * @internal
     */
    serialize() {
        const cmdAndHeaders = this.serializeCmdAndHeaders();
        if (this.isBinaryBody) {
            return FrameImpl.toUnit8Array(cmdAndHeaders, this._binaryBody).buffer;
        }
        else {
            return cmdAndHeaders + this._body + BYTE.NULL;
        }
    }
    serializeCmdAndHeaders() {
        const lines = [this.command];
        if (this.skipContentLengthHeader) {
            delete this.headers['content-length'];
        }
        for (const name of Object.keys(this.headers || {})) {
            const value = this.headers[name];
            if (this.escapeHeaderValues &&
                this.command !== 'CONNECT' &&
                this.command !== 'CONNECTED') {
                lines.push(`${name}:${FrameImpl.hdrValueEscape(`${value}`)}`);
            }
            else {
                lines.push(`${name}:${value}`);
            }
        }
        if (this.isBinaryBody ||
            (!this.isBodyEmpty() && !this.skipContentLengthHeader)) {
            lines.push(`content-length:${this.bodyLength()}`);
        }
        return lines.join(BYTE.LF) + BYTE.LF + BYTE.LF;
    }
    isBodyEmpty() {
        return this.bodyLength() === 0;
    }
    bodyLength() {
        const binaryBody = this.binaryBody;
        return binaryBody ? binaryBody.length : 0;
    }
    /**
     * Compute the size of a UTF-8 string by counting its number of bytes
     * (and not the number of characters composing the string)
     */
    static sizeOfUTF8(s) {
        return s ? new TextEncoder().encode(s).length : 0;
    }
    static toUnit8Array(cmdAndHeaders, binaryBody) {
        const uint8CmdAndHeaders = new TextEncoder().encode(cmdAndHeaders);
        const nullTerminator = new Uint8Array([0]);
        const uint8Frame = new Uint8Array(uint8CmdAndHeaders.length + binaryBody.length + nullTerminator.length);
        uint8Frame.set(uint8CmdAndHeaders);
        uint8Frame.set(binaryBody, uint8CmdAndHeaders.length);
        uint8Frame.set(nullTerminator, uint8CmdAndHeaders.length + binaryBody.length);
        return uint8Frame;
    }
    /**
     * Serialize a STOMP frame as per STOMP standards, suitable to be sent to the STOMP broker.
     *
     * @internal
     */
    static marshall(params) {
        const frame = new FrameImpl(params);
        return frame.serialize();
    }
    /**
     *  Escape header values
     */
    static hdrValueEscape(str) {
        return str
            .replace(/\\/g, '\\\\')
            .replace(/\r/g, '\\r')
            .replace(/\n/g, '\\n')
            .replace(/:/g, '\\c');
    }
    /**
     * UnEscape header values
     */
    static hdrValueUnEscape(str) {
        return str
            .replace(/\\r/g, '\r')
            .replace(/\\n/g, '\n')
            .replace(/\\c/g, ':')
            .replace(/\\\\/g, '\\');
    }
}
//# sourceMappingURL=frame-impl.js.map