[fix] normalized error code handling:

  - codes are string representation of the number
  - description is lowercased string
  - constants simply reference the string code

nats-base-client/error.ts

@@ -31,7 +31,7 @@ export enum ErrorCode {
   InvalidOption = "INVALID_OPTION",
   InvalidPayload = "INVALID_PAYLOAD",
   MaxPayloadExceeded = "MAX_PAYLOAD_EXCEEDED",
-  NoResponders = "NO_RESPONDERS",
+  NoResponders = "503",
   NotFunction = "NOT_FUNC",
   RequestError = "REQUEST_ERROR",
   ServerOptionNotAvailable = "SERVER_OPT_NA",
@@ -43,11 +43,11 @@ export enum ErrorCode {
   WssRequired = "WSS_REQUIRED",
 
   // jetstream
-  JetStreamNotEnabled = "JETSTREAM_NOT_ENABLED",
   JetStreamInvalidAck = "JESTREAM_INVALID_ACK",
-  JetStream404NoMessages = "404_NO_MESSAGES",
-  JetStream408RequestTimeout = "408_REQUEST_TIMEOUT",
-  JetStream409MaxAckPendingExceeded = "409_MAX_ACK_PENDING_EXCEEDED",
+  JetStream404NoMessages = "404",
+  JetStream408RequestTimeout = "408",
+  JetStream409MaxAckPendingExceeded = "409",
+  JetStreamNotEnabled = "503",
 
   // emitted by the server
   AuthorizationViolation = "AUTHORIZATION_VIOLATION",

nats-base-client/jsbaseclient_api.ts

@@ -24,9 +24,9 @@ import {
   StreamNames,
 } from "./types.ts";
 import { Codec, JSONCodec } from "./codec.ts";
-import { ErrorCode, NatsError } from "./error.ts";
 import { extend } from "./util.ts";
 import { NatsConnectionImpl } from "./nats.ts";
+import { checkJsErrorCode } from "./jsutil.ts";
 
 const defaultPrefix = "$JS.API";
 const defaultTimeout = 5000;
@@ -98,15 +98,11 @@ export class BaseApiClient {
   parseJsResponse(m: Msg): unknown {
     const v = this.jc.decode(m.data);
     const r = v as ApiResponse;
-
     if (r.error) {
-      if (r.error.code === 503) {
-        throw NatsError.errorForCode(
-          ErrorCode.JetStreamNotEnabled,
-          new Error(r.error.description),
-        );
+      const err = checkJsErrorCode(r.error.code, r.error.description);
+      if (err !== null) {
+        throw err;
       }
-      throw new NatsError(r.error.description, `${r.error.code}`);
     }
     return v;
   }

nats-base-client/jsclient.ts

@@ -39,7 +39,13 @@ import {
   RequestOptions,
 } from "./types.ts";
 import { BaseApiClient } from "./jsbaseclient_api.ts";
-import { nanos, validateDurableName, validateStreamName } from "./jsutil.ts";
+import {
+  checkJsError,
+  isFlowControlMsg,
+  nanos,
+  validateDurableName,
+  validateStreamName,
+} from "./jsutil.ts";
 import { ConsumerAPIImpl } from "./jsconsumer_api.ts";
 import { toJsMsg } from "./jsmsg.ts";
 import {
@@ -53,8 +59,8 @@ import { QueuedIterator, QueuedIteratorImpl } from "./queued_iterator.ts";
 import { Timeout, timeout } from "./util.ts";
 import { createInbox } from "./protocol.ts";
 import { headers } from "./headers.ts";
-import { consumerOpts, isConsumerOptsBuilder } from "./consumeropts.ts";
 import type { ConsumerOptsBuilder } from "./consumeropts.ts";
+import { consumerOpts, isConsumerOptsBuilder } from "./consumeropts.ts";
 
 export interface JetStreamSubscriptionInfoable {
   info: JetStreamSubscriptionInfo | null;
@@ -521,33 +527,3 @@ function autoAckJsMsg(data: JsMsg | null) {
     data.ack();
   }
 }
-
-function isFlowControlMsg(msg: Msg): boolean {
-  const h = msg.headers;
-  if (!h) {
-    return false;
-  }
-  return h.code >= 100 && h.code < 200;
-}
-
-function checkJsError(msg: Msg): NatsError | null {
-  const h = msg.headers;
-  if (!h) {
-    return null;
-  }
-  if (h.code < 300) {
-    return null;
-  }
-  switch (h.code) {
-    case 404:
-      return NatsError.errorForCode(ErrorCode.JetStream404NoMessages);
-    case 408:
-      return NatsError.errorForCode(ErrorCode.JetStream408RequestTimeout);
-    case 409:
-      return NatsError.errorForCode(
-        ErrorCode.JetStream409MaxAckPendingExceeded,
-      );
-    default:
-      return NatsError.errorForCode(ErrorCode.Unknown, new Error(h.status));
-  }
-}

nats-base-client/jsutil.ts

@@ -16,9 +16,11 @@ import {
   AckPolicy,
   ConsumerConfig,
   DeliverPolicy,
+  Msg,
   Nanos,
   ReplayPolicy,
 } from "./types.ts";
+import { ErrorCode, NatsError } from "./error.ts";
 
 export function validateDurableName(name?: string) {
   return validateName("durable", name);
@@ -62,3 +64,41 @@ export function nanos(millis: number): Nanos {
 export function millis(ns: Nanos) {
   return ns / 1000000;
 }
+
+export function isFlowControlMsg(msg: Msg): boolean {
+  const h = msg.headers;
+  if (!h) {
+    return false;
+  }
+  return h.code >= 100 && h.code < 200;
+}
+
+export function checkJsError(msg: Msg): NatsError | null {
+  const h = msg.headers;
+  if (!h) {
+    return null;
+  }
+  return checkJsErrorCode(h.code, h.status);
+}
+
+export function checkJsErrorCode(
+  code: number,
+  description = "",
+): NatsError | null {
+  if (code < 300) {
+    return null;
+  }
+  description = description.toLowerCase();
+  switch (code) {
+    case 503:
+      return NatsError.errorForCode(
+        ErrorCode.JetStreamNotEnabled,
+        new Error(description),
+      );
+    default:
+      if (description === "") {
+        description = ErrorCode.Unknown;
+      }
+      return new NatsError(description, `${code}`);
+  }
+}

nats-base-client/msg.ts

@@ -19,19 +19,19 @@ import type { MsgArg } from "./parser.ts";
 import { TD } from "./encoders.ts";
 import { ErrorCode, NatsError } from "./error.ts";
 
-const noResponders = "503";
-
 export function isRequestError(msg: Msg): (NatsError | null) {
   if (msg && msg.headers) {
     const headers = msg.headers as MsgHdrsImpl;
     if (headers.hasError) {
-      if (headers.status === noResponders) {
+      if (headers.status === "503") {
         return NatsError.errorForCode(ErrorCode.NoResponders);
       } else {
-        return new NatsError(
-          headers.status,
-          ErrorCode.RequestError,
-        );
+        let desc = headers.get("description");
+        if (desc === "") {
+          desc = ErrorCode.RequestError;
+        }
+        desc = desc.toLowerCase();
+        return new NatsError(desc, headers.status);
       }
     }
   }

tests/jetstream_test.ts

@@ -221,7 +221,7 @@ Deno.test("jetstream - publish require last message id", async () => {
       await js.publish(subj, Empty, { msgID: "b", expect: { lastMsgID: "b" } });
     },
     Error,
-    "wrong last msg ID: a",
+    "wrong last msg id: a",
   );
 
   pa = await js.publish(subj, Empty, {
@@ -335,12 +335,12 @@ Deno.test("jetstream - pull no messages", async () => {
     ack_policy: AckPolicy.Explicit,
   });
   const js = nc.jetstream();
-  assertThrowsAsync(
+  await assertThrowsAsync(
     async () => {
       await js.pull(stream, "me");
     },
     Error,
-    "404 No Messages",
+    "no messages",
   );
 
   await cleanup(ns, nc);
@@ -384,7 +384,7 @@ Deno.test("jetstream - pull batch no messages", async () => {
       await js.pull(stream, "me");
     },
     Error,
-    "404 No Messages",
+    "no messages",
   );
   await cleanup(ns, nc);
 });
@@ -1284,7 +1284,7 @@ Deno.test("jetstream - cross account pull", async () => {
       await js.pull(stream, "me");
     },
     Error,
-    "No Messages",
+    "no messages",
   );
 
   await cleanup(ns, admin, nc);

tests/jsm_test.ts

@@ -466,7 +466,7 @@ Deno.test("jsm - get message", async () => {
       await jsm.streams.getMessage(stream, 3);
     },
     Error,
-    "stream store EOF",
+    "stream store eof",
   );
 
   await cleanup(ns, nc);