fix: setting triggers.crons:[] in Wrangler config should delete deployed cron schedules

Author: petebacondarwin

.changeset/shaky-planets-feel.md

@@ -0,0 +1,5 @@
+---
+"wrangler": patch
+---
+
+fix: setting triggers.crons:[] in Wrangler config should delete deployed cron schedules

packages/wrangler/src/__tests__/config/configuration.test.ts

@@ -114,7 +114,7 @@ describe("normalizeAndValidateConfig()", () => {
 			ai: undefined,
 			version_metadata: undefined,
 			triggers: {
-				crons: [],
+				crons: undefined,
 			},
 			unsafe: {
 				bindings: undefined,

packages/wrangler/src/config/config.ts

@@ -326,7 +326,7 @@ export const defaultWranglerConfig: Config = {
 	jsx_fragment: "React.Fragment",
 	migrations: [],
 	triggers: {
-		crons: [],
+		crons: undefined,
 	},
 	rules: [],
 	build: { command: undefined, watch_dir: "./src", cwd: undefined },

packages/wrangler/src/config/environment.ts

@@ -280,10 +280,10 @@ interface EnvironmentInheritable {
 	 *
 	 * More details here https://developers.cloudflare.com/workers/platform/cron-triggers
 	 *
-	 * @default {crons:[]}
+	 * @default {crons: undefined}
 	 * @inheritable
 	 */
-	triggers: { crons: string[] };
+	triggers: { crons: string[] | undefined };
 
 	/**
 	 * Specify limits for runtime behavior.

packages/wrangler/src/config/validation.ts

@@ -17,7 +17,6 @@ import {
 	inheritableInLegacyEnvironments,
 	isBoolean,
 	isMutuallyExclusiveWith,
-	isObjectWith,
 	isOptionalProperty,
 	isRequiredProperty,
 	isString,
@@ -1122,8 +1121,8 @@ function normalizeAndValidateEnvironment(
 			topLevelEnv,
 			rawEnv,
 			"triggers",
-			isObjectWith("crons"),
-			{ crons: [] }
+			validateTriggers,
+			{ crons: undefined }
 		),
 		assets: normalizeAndValidateAssets(diagnostics, topLevelEnv, rawEnv),
 		limits: normalizeAndValidateLimits(diagnostics, topLevelEnv, rawEnv),
@@ -1509,6 +1508,37 @@ const validateAndNormalizeRules = (
 	);
 };
 
+const validateTriggers: ValidatorFn = (diagnostics, field, value: unknown) => {
+	if (value === undefined || value === null) {
+		return true;
+	}
+
+	if (typeof value !== "object") {
+		diagnostics.errors.push(
+			`Expected "${field}" to be of type object but got ${JSON.stringify(
+				value
+			)}.`
+		);
+		return false;
+	}
+
+	let isValid = true;
+
+	if ("crons" in value && !Array.isArray(value.crons)) {
+		diagnostics.errors.push(
+			`Expected "${field}.crons" to be of type array, but got ${JSON.stringify(value)}.`
+		);
+		isValid = false;
+	}
+
+	isValid =
+		validateAdditionalProperties(diagnostics, field, Object.keys(value), [
+			"crons",
+		]) && isValid;
+
+	return isValid;
+};
+
 const validateRules =
 	(envName: string): ValidatorFn =>
 	(diagnostics, field, envValue, config) => {

packages/wrangler/src/dev/miniflare.ts

@@ -1027,7 +1027,7 @@ export async function buildMiniflareOptions(
 	internalObjects: CfDurableObject[];
 	entrypointNames: string[];
 }> {
-	if (config.crons.length > 0 && !config.testScheduled) {
+	if (config.crons?.length && !config.testScheduled) {
 		if (!didWarnMiniflareCronSupport) {
 			didWarnMiniflareCronSupport = true;
 			logger.warn(

packages/wrangler/src/triggers/deploy.ts

@@ -38,7 +38,7 @@ export default async function triggersDeploy(
 ): Promise<string[] | void> {
 	const { config, accountId, name: scriptName } = props;
 
-	const triggers = props.triggers || config.triggers?.crons;
+	const schedules = props.triggers || config.triggers?.crons;
 	const routes =
 		props.routes ?? config.routes ?? (config.route ? [config.route] : []) ?? [];
 	const routesOnly: Array<Route> = [];
@@ -258,17 +258,18 @@ export default async function triggersDeploy(
 	}
 
 	// Configure any schedules for the script.
-	// TODO: rename this to `schedules`?
-	if (triggers && triggers.length) {
+	// If schedules is not defined then we just leave whatever is previously deployed alone.
+	// If it is an empty array we will remove all schedules.
+	if (schedules) {
 		deployments.push(
 			fetchResult(`${workerUrl}/schedules`, {
 				// Note: PUT will override previous schedules on this script.
 				method: "PUT",
-				body: JSON.stringify(triggers.map((cron) => ({ cron }))),
+				body: JSON.stringify(schedules.map((cron) => ({ cron }))),
 				headers: {
 					"Content-Type": "application/json",
 				},
-			}).then(() => triggers.map((trigger) => `schedule: ${trigger}`))
+			}).then(() => schedules.map((trigger) => `schedule: ${trigger}`))
 		);
 	}