Optionalmessage: stringOptionaloptions: ErrorOptions & { status?: number }OptionalcauseReadonlynameOptionalstackOptional ReadonlystatusHTTP status code of the rejected connection attempt, if known. Only set when the EventSource implementation exposes it — the polyfill used in Node.js and when custom headers (eg authorization) are required does, while native EventSource implementations (browser and Node.js) do not.
StaticstackThe Error.stackTraceLimit property specifies the number of stack frames
collected by a stack trace (whether generated by new Error().stack or
Error.captureStackTrace(obj)).
The default value is 10 but may be set to any valid JavaScript number. Changes
will affect any stack trace captured after the value has been changed.
If set to a non-number value, or set to a negative number, stack traces will not capture any frames.
StaticcaptureCreates a .stack property on targetObject, which when accessed returns
a string representing the location in the code at which
Error.captureStackTrace() was called.
const myObject = {};
Error.captureStackTrace(myObject);
myObject.stack; // Similar to `new Error().stack`
The first line of the trace will be prefixed with
${myObject.name}: ${myObject.message}.
The optional constructorOpt argument accepts a function. If given, all frames
above constructorOpt, including constructorOpt, will be omitted from the
generated stack trace.
The constructorOpt argument is useful for hiding implementation
details of error generation from the user. For instance:
function a() {
b();
}
function b() {
c();
}
function c() {
// Create an error without stack trace to avoid calculating the stack trace twice.
const { stackTraceLimit } = Error;
Error.stackTraceLimit = 0;
const error = new Error();
Error.stackTraceLimit = stackTraceLimit;
// Capture the stack trace above function b
Error.captureStackTrace(error, b); // Neither function c, nor b is included in the stack trace
throw error;
}
a();
OptionalconstructorOpt: FunctionStaticisIndicates whether the argument provided is a built-in Error instance or not.
Staticprepare
Thrown when the EventSource connection could not be established, or was rejected by the server. Transient failures (network drops, 5xx, 408, 429) are reconnected internally and emitted as
reconnectevents; a permanent rejection (any other 4xx, eg an expired token) errors the stream with this class so consumers can react — checkstatusfor the rejection code.