fix: disable observability on deploy if not explicitly defined in config

Changes the deploy behavior deploys using the new versions API to disable observability if it isn't explicitly defined in the user's wrangler.toml.

.changeset/old-mugs-begin.md

@@ -0,0 +1,7 @@
+---
+"wrangler": patch
+---
+
+fix: disable observability on deploy if not explicitly defined in config
+
+When deploying a Worker that has observability enabled in the deployed version but not specified in the `wrangler.toml` Wrangler will now set observability to disabled for the new version to match the `wrangler.toml` as the source of truth.

packages/wrangler/src/__tests__/deploy.test.ts

@@ -10880,6 +10880,29 @@ export default{
 				Current Version ID: Galaxy-Class"
 			`);
 		});
+
+		it("should disable observability if not explicitly defined", async () => {
+			writeWranglerToml({});
+			await fs.promises.writeFile("index.js", `export default {};`);
+			mockSubDomainRequest();
+			mockUploadWorkerRequest({
+				expectedSettingsPatch: {
+					observability: {
+						enabled: false,
+					},
+				},
+			});
+
+			await runWrangler("publish index.js");
+			expect(std.out).toMatchInlineSnapshot(`
+				"Total Upload: xx KiB / gzip: xx KiB
+				Worker Startup Time: 100 ms
+				Uploaded test-name (TIMINGS)
+				Deployed test-name triggers (TIMINGS)
+				  https://test-name.test-sub-domain.workers.dev
+				Current Version ID: Galaxy-Class"
+			`);
+		});
 	});
 });
 

packages/wrangler/src/__tests__/helpers/mock-upload-worker.ts

@@ -3,6 +3,7 @@ import { createFetchResult, msw } from "./msw";
 import { serialize, toString } from "./serialize-form-data-entry";
 import type { WorkerMetadata } from "../../deployment-bundle/create-worker-upload-form";
 import type { CfWorkerInit } from "../../deployment-bundle/worker";
+import type { NonVersionedScriptSettings } from "../../versions/api";
 import type { AssetConfig } from "@cloudflare/workers-shared";
 import type { HttpResponseResolver } from "msw";
 
@@ -35,6 +36,7 @@ export function mockUploadWorkerRequest(
 		};
 		useOldUploadApi?: boolean;
 		expectedObservability?: CfWorkerInit["observability"];
+		expectedSettingsPatch?: Partial<NonVersionedScriptSettings>;
 	} = {}
 ) {
 	const expectedScriptName = (options.expectedScriptName ??= "test-name");
@@ -178,6 +180,7 @@ export function mockUploadWorkerRequest(
 		expectedDispatchNamespace,
 		useOldUploadApi,
 		expectedObservability,
+		expectedSettingsPatch,
 	} = options;
 	if (env && !legacyEnv) {
 		msw.use(
@@ -212,7 +215,15 @@ export function mockUploadWorkerRequest(
 			),
 			http.patch(
 				"*/accounts/:accountId/workers/scripts/:scriptName/script-settings",
-				() => HttpResponse.json(createFetchResult({}))
+				async ({ request }) => {
+					const body = await request.json();
+
+					if ("expectedSettingsPatch" in options) {
+						expect(body).toEqual(expectedSettingsPatch);
+					}
+
+					return HttpResponse.json(createFetchResult({}));
+				}
 			)
 		);
 	}

packages/wrangler/src/deploy/deploy.ts

@@ -829,11 +829,14 @@ See https://developers.cloudflare.com/workers/platform/compatibility-dates for m
 					versionMap.set(versionResult.id, 100);
 					await createDeployment(accountId, scriptName, versionMap, undefined);
 
-					// Update tail consumers and logpush settings
+					// Update tail consumers, logpush, and observability settings
 					await patchNonVersionedScriptSettings(accountId, scriptName, {
 						tail_consumers: worker.tail_consumers,
 						logpush: worker.logpush,
-						observability: worker.observability,
+						// If the user hasn't specified observability assume that they want it disabled if they have it on.
+						// This is a no-op in the event that they don't have observability enabled, but will remove observability
+						// if it has been removed from their wrangler.toml
+						observability: worker.observability ?? { enabled: false },
 					});
 
 					const { available_on_subdomain } = await fetchResult<{

packages/wrangler/src/versions/api.ts

@@ -125,7 +125,7 @@ export async function createDeployment(
 	);
 }
 
-type NonVersionedScriptSettings = {
+export type NonVersionedScriptSettings = {
 	logpush: boolean;
 	tail_consumers: TailConsumer[];
 	observability: Observability;