src/http-api.js
function parseErrorResponse(response, body) {
    const httpStatus = response.statusCode;
    const contentType = getResponseContentType(response);

    let err;
    if (contentType) {
        if (contentType.type === 'application/json') {
            err = new module.exports.MatrixError(JSON.parse(body));
        } else if (contentType.type === 'text/plain') {
            err = new Error(`Server returned ${httpStatus} error: ${body}`);
        }
    }

    if (!err) {
        err = new Error(`Server returned ${httpStatus} error`);
    }
    err.httpStatus = httpStatus;
    return err;
}
function parseErrorResponse(response, body) {
    const httpStatus = response.statusCode;
    const contentType = getResponseContentType(response);

    let err;
    if (contentType) {
        if (contentType.type === 'application/json') {
            err = new module.exports.MatrixError(JSON.parse(body));
        } else if (contentType.type === 'text/plain') {
            err = new Error(`Server returned ${httpStatus} error: ${body}`);
        }
    }

    if (!err) {
        err = new Error(`Server returned ${httpStatus} error`);
    }
    err.httpStatus = httpStatus;
    return err;
}
function parseErrorResponse ( response , body ) { const httpStatus = response . statusCode ; const contentType = getResponseContentType ( response ) ; let err ; if ( contentType ) { if ( contentType . type === 'application/json' ) { err = new module . exports . MatrixError ( JSON . parse ( body ) ) ; } else if ( contentType . type === 'text/plain' ) { err = new Error ( ` ${ httpStatus } ${ body } ` ) ; } } if ( ! err ) { err = new Error ( ` ${ httpStatus } ` ) ; } err . httpStatus = httpStatus ; return err ; }
Attempt to turn an HTTP error response into a Javascript Error.

If it is a JSON response, we will parse it into a MatrixError. Otherwise
we return a generic Error.

@param {XMLHttpRequest|http.IncomingMessage} response response object
@param {String} body raw body of the response
@returns {Error}
Attempt to turn an HTTP error response into a Javascript Error .