feat: allow extra root properties in configuration file

This enables other tools to store data in the configuration file. Nonetheless, the user will see a message (at the INFO level) for configuration fields which are not understood by the agent. This is to help diagnose unexpected outcomes while applying the agent.

build/schema/schema.yml

@@ -406,7 +406,6 @@
 
 - $id: config
   type: object
-  additionalProperties: false
   properties:
     # server
     agent: {$ref: agent}

components/setup/node/index.test.mjs

@@ -50,7 +50,7 @@ global.GLOBAL_PROMPTS = () => ({ value: false });
 {
   await writeFileAsync(
     new URL(`${directory}/appmap.yml`),
-    "{valid: yaml}",
+    "invalid configuration type",
     "utf8",
   );
   assertEqual(await mainAsync({ ...process, cwd }), false);

components/validate/ajv/.build.yml

@@ -1,4 +1,5 @@
 branches: [test, node, browser]
 dependencies:
   - util
+  - log
   - expect

components/validate/ajv/index.mjs

@@ -3,13 +3,15 @@ import Treeify from "treeify";
 import AjvErrorTree from "ajv-error-tree";
 import { schema } from "../../../dist/schema.mjs";
 
+const {ownKeys} = Reflect;
 const _Map = Map;
 const { asTree } = Treeify;
 
 export default (dependencies) => {
   const {
-    util: { assert, coalesce },
+    util: { hasOwnProperty, assert, coalesce },
     expect: { expect },
+    log: {logGuardInfo},
   } = dependencies;
   const naming = new _Map([
     ["config", "configuration"],
@@ -39,9 +41,20 @@ export default (dependencies) => {
       }
     };
   };
+  const validateConfig = generateValidate("config");
+  const config_schema = schema.find(({$id}) => $id === "config");
   return {
     validateMessage: generateValidate("message"),
-    validateConfig: generateValidate("config"),
+    validateConfig: (config) => {
+      validateConfig(config);
+      for (const key of ownKeys(config)) {
+        logGuardInfo(
+          !hasOwnProperty(config_schema.properties, key),
+          "Configuration property not recognized by the agent: %j",
+          key,
+        );
+      }
+    },
     validateConfiguration: generateValidate("configuration"),
     validateSourceMap: generateValidate("source-map"),
   };

components/validate/ajv/index.test.mjs

@@ -1,13 +1,20 @@
-import { assertThrow } from "../../__fixture__.mjs";
+import { assertEqual, assertThrow } from "../../__fixture__.mjs";
 import { buildTestDependenciesAsync } from "../../build.mjs";
 import Validation from "./index.mjs";
 
 const { validateConfig } = Validation(
   await buildTestDependenciesAsync(import.meta.url),
 );
+
+assertEqual(
+  validateConfig({ extra: "extra-root-property" }),
+  undefined,
+);
+
 assertThrow(() => {
-  validateConfig({ mode: "invalid-mode" });
+  validateConfig("invalid-configuration-type");
 }, /^AppmapError: invalid configuration\n/u);
+
 assertThrow(() => {
   validateConfig({ engine: "invalid-engine-format" });
 }, /^AppmapError: invalid configuration\n/u);