Validate merged comment-ops config against a JSON Schema

app/config-schema.js

@@ -0,0 +1,74 @@
+import Ajv2020 from "ajv/dist/2020.js";
+
+const toggleCommandSchema = {
+  additionalProperties: false,
+  properties: {
+    enabled: {
+      type: "boolean",
+    },
+  },
+  required: ["enabled"],
+  type: "object",
+};
+
+const labelCommandSchema = {
+  additionalProperties: false,
+  properties: {
+    allowedLabels: {
+      items: {
+        type: "string",
+      },
+      type: "array",
+    },
+    enabled: {
+      type: "boolean",
+    },
+  },
+  required: ["allowedLabels", "enabled"],
+  type: "object",
+};
+
+export const configSchema = {
+  $schema: "https://json-schema.org/draft/2020-12/schema",
+  additionalProperties: false,
+  properties: {
+    commands: {
+      additionalProperties: false,
+      properties: {
+        close: toggleCommandSchema,
+        label: labelCommandSchema,
+        removeLabel: labelCommandSchema,
+        reopen: toggleCommandSchema,
+        reviewer: toggleCommandSchema,
+        transfer: toggleCommandSchema,
+      },
+      required: [
+        "close",
+        "label",
+        "removeLabel",
+        "reopen",
+        "reviewer",
+        "transfer",
+      ],
+      type: "object",
+    },
+  },
+  required: ["commands"],
+  type: "object",
+};
+
+const validator = new Ajv2020({
+  allErrors: true,
+}).compile(configSchema);
+
+export function validateConfig(config) {
+  if (validator(config)) {
+    return;
+  }
+
+  throw new Error(
+    validator.errors
+      .map((error) => `${error.instancePath || "/"} ${error.message}`)
+      .join("; "),
+  );
+}

app/config-schema.test.js

@@ -0,0 +1,39 @@
+import { validateConfig } from "./config-schema.js";
+import { defaultConfig } from "./default-config.js";
+
+describe("config-schema", () => {
+  test("default config is valid", () => {
+    expect(() => validateConfig(defaultConfig)).not.toThrow();
+  });
+
+  test("enabled label config with allowed labels is valid", () => {
+    const config = structuredClone(defaultConfig);
+    config.commands.label.enabled = true;
+    config.commands.label.allowedLabels = ["bug", "help wanted"];
+
+    expect(() => validateConfig(config)).not.toThrow();
+  });
+
+  test("throws when enabled is not a boolean", () => {
+    const config = structuredClone(defaultConfig);
+    config.commands.close.enabled = "true";
+
+    expect(() => validateConfig(config)).toThrow("/commands/close/enabled");
+  });
+
+  test("throws when allowedLabels is not an array", () => {
+    const config = structuredClone(defaultConfig);
+    config.commands.label.allowedLabels = "bug";
+
+    expect(() => validateConfig(config)).toThrow(
+      "/commands/label/allowedLabels",
+    );
+  });
+
+  test("throws when command config includes unknown properties", () => {
+    const config = structuredClone(defaultConfig);
+    config.commands.transfer.target = "repo";
+
+    expect(() => validateConfig(config)).toThrow("/commands/transfer");
+  });
+});

app/router.js

@@ -1,5 +1,6 @@
 import { addReaction, reportError } from "./github.js";
 import { getAuthToken } from "./auth.js";
+import { validateConfig } from "./config-schema.js";
 import { defaultConfig } from "./default-config.js";
 
 import { Octokit } from "@octokit/core";
@@ -44,14 +45,13 @@ export async function router(auth, id, payload, verbose) {
   }
 
   try {
-    // TODO validate against schema
-    // noinspection JSUnusedGlobalSymbols
     const { config } = await octokit.config.get({
       owner: payload.repository.owner.login,
       repo: payload.repository.name,
       path: ".github/comment-ops.yml",
       defaults: (configs) => deepmerge.all([defaultConfig, ...configs]),
     });
+    validateConfig(config);
 
     for (const command of commands) {
       const result = command.enabled(config);