class ResponseMetaData { constructor(request) { let {responseHeaders} = request; this.headers = {}; this.contentType = this.contentDisposition = null; for (let h of responseHeaders) { if (/^\s*Content-(Type|Disposition)\s*$/i.test(h.name)) { let propertyName = RegExp.$1; propertyName = `content${propertyName.charAt(0).toUpperCase()}${propertyName.substring(1).toLowerCase()}`; this[propertyName] = h.value; this.headers[propertyName] = h; } } this.forcedUTF8 = false; } get charset() { let charset = ""; if (this.contentType) { let m = this.contentType.match(/;\s*charset\s*=\s*(\S+)/); if (m) { charset = m[1]; } } Object.defineProperty(this, "charset", { value: charset, writable: false, configurable: true }); return charset; } get isUTF8() { return /^utf-8$/i.test(this.charset); } forceUTF8() { if (!(this.forcedUTF8 || this.isUTF8)) { let h = this.headers.contentType; if (h) { h.value = h.value.replace(/;\s*charset\s*=.*|$/, "; charset=utf8"); this.forcedUTF8 = true; } // if the header doesn't exist the browser should default to UTF-8 anyway } return this.forcedUTF8; } createDecoder() { if (this.charset) { try { return new TextDecoder(this.charset); } catch (e) { console.error(e); } } return new TextDecoder("utf-8"); } };