[APM] Improve router types

x-pack/plugins/apm/common/runtime_types/merge/index.test.ts

@@ -0,0 +1,71 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+import * as t from 'io-ts';
+import { isLeft } from 'fp-ts/lib/Either';
+import { merge } from './';
+import { jsonRt } from '../json_rt';
+
+describe('merge', () => {
+  it('fails on one or more errors', () => {
+    const type = merge([t.type({ foo: t.string }), t.type({ bar: t.number })]);
+
+    const result = type.decode({ foo: '' });
+
+    expect(isLeft(result)).toBe(true);
+  });
+
+  it('merges left to right', () => {
+    const typeBoolean = merge([
+      t.type({ foo: t.string }),
+      t.type({ foo: jsonRt.pipe(t.boolean) }),
+    ]);
+
+    const resultBoolean = typeBoolean.decode({
+      foo: 'true',
+    });
+
+    // @ts-expect-error
+    expect(resultBoolean.right).toEqual({
+      foo: true,
+    });
+
+    const typeString = merge([
+      t.type({ foo: jsonRt.pipe(t.boolean) }),
+      t.type({ foo: t.string }),
+    ]);
+
+    const resultString = typeString.decode({
+      foo: 'true',
+    });
+
+    // @ts-expect-error
+    expect(resultString.right).toEqual({
+      foo: 'true',
+    });
+  });
+
+  it('deeply merges values', () => {
+    const type = merge([
+      t.type({ foo: t.type({ baz: t.string }) }),
+      t.type({ foo: t.type({ bar: t.string }) }),
+    ]);
+
+    const result = type.decode({
+      foo: {
+        bar: '',
+        baz: '',
+      },
+    });
+
+    // @ts-expect-error
+    expect(result.right).toEqual({
+      foo: {
+        bar: '',
+        baz: '',
+      },
+    });
+  });
+});

x-pack/plugins/apm/common/runtime_types/merge/index.ts

@@ -0,0 +1,68 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+import * as t from 'io-ts';
+import { merge as lodashMerge } from 'lodash';
+import { isLeft } from 'fp-ts/lib/Either';
+import { ValuesType } from 'utility-types';
+
+export type MergeType<
+  T extends t.Any[],
+  U extends ValuesType<T> = ValuesType<T>
+> = t.Type<U['_A'], U['_O'], U['_I']> & {
+  _tag: 'MergeType';
+  types: T;
+};
+
+// this is similar to t.intersection, but does a deep merge
+// instead of a shallow merge
+
+export function merge<A extends t.Mixed, B extends t.Mixed>(
+  types: [A, B]
+): MergeType<[A, B]>;
+
+export function merge(types: t.Any[]) {
+  const mergeType = new t.Type(
+    'merge',
+    (u): u is unknown => {
+      return types.every((type) => type.is(u));
+    },
+    (input, context) => {
+      const errors: t.Errors = [];
+
+      const successes: unknown[] = [];
+
+      const results = types.map((type, index) =>
+        type.validate(
+          input,
+          context.concat({
+            key: String(index),
+            type,
+            actual: input,
+          })
+        )
+      );
+
+      results.forEach((result) => {
+        if (isLeft(result)) {
+          errors.push(...result.left);
+        } else {
+          successes.push(result.right);
+        }
+      });
+
+      const mergedValues = lodashMerge({}, ...successes);
+
+      return errors.length > 0 ? t.failures(errors) : t.success(mergedValues);
+    },
+    (a) => types.reduce((val, type) => type.encode(val), a)
+  );
+
+  return {
+    ...mergeType,
+    _tag: 'MergeType',
+    types,
+  };
+}

x-pack/plugins/apm/common/runtime_types/strict_keys_rt/index.test.ts

@@ -0,0 +1,106 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+import * as t from 'io-ts';
+import { isRight, isLeft } from 'fp-ts/lib/Either';
+import { strictKeysRt } from './';
+import { jsonRt } from '../json_rt';
+
+describe('strictKeysRt', () => {
+  it('correctly and deeply validates object keys', () => {
+    const checks: Array<{ type: t.Type<any>; passes: any[]; fails: any[] }> = [
+      {
+        type: t.intersection([
+          t.type({ foo: t.string }),
+          t.partial({ bar: t.string }),
+        ]),
+        passes: [{ foo: '' }, { foo: '', bar: '' }],
+        fails: [
+          { foo: '', unknownKey: '' },
+          { foo: '', bar: '', unknownKey: '' },
+        ],
+      },
+      {
+        type: t.type({
+          path: t.union([
+            t.type({ serviceName: t.string }),
+            t.type({ transactionType: t.string }),
+          ]),
+        }),
+        passes: [
+          { path: { serviceName: '' } },
+          { path: { transactionType: '' } },
+        ],
+        fails: [
+          { path: { serviceName: '', unknownKey: '' } },
+          { path: { transactionType: '', unknownKey: '' } },
+          { path: { serviceName: '', transactionType: '' } },
+          { path: { serviceName: '' }, unknownKey: '' },
+        ],
+      },
+      {
+        type: t.intersection([
+          t.type({ query: t.type({ bar: t.string }) }),
+          t.partial({ query: t.partial({ _debug: t.boolean }) }),
+        ]),
+        passes: [{ query: { bar: '', _debug: true } }],
+        fails: [{ query: { _debug: true } }],
+      },
+    ];
+
+    checks.forEach((check) => {
+      const { type, passes, fails } = check;
+
+      const strictType = strictKeysRt(type);
+
+      passes.forEach((value) => {
+        const result = strictType.decode(value);
+
+        if (!isRight(result)) {
+          throw new Error(
+            `Expected ${JSON.stringify(
+              value
+            )} to be allowed, but validation failed with ${
+              result.left[0].message
+            }`
+          );
+        }
+      });
+
+      fails.forEach((value) => {
+        const result = strictType.decode(value);
+
+        if (!isLeft(result)) {
+          throw new Error(
+            `Expected ${JSON.stringify(
+              value
+            )} to be disallowed, but validation succeeded`
+          );
+        }
+      });
+    });
+  });
+
+  it('does not support piped types', () => {
+    const typeA = t.type({
+      query: t.type({ filterNames: jsonRt.pipe(t.array(t.string)) }),
+    } as Record<string, any>);
+
+    const typeB = t.partial({
+      query: t.partial({ _debug: jsonRt.pipe(t.boolean) }),
+    });
+
+    const value = {
+      query: {
+        _debug: 'true',
+        filterNames: JSON.stringify(['host', 'agentName']),
+      },
+    };
+
+    const pipedType = strictKeysRt(typeA.pipe(typeB));
+
+    expect(isLeft(pipedType.decode(value))).toBe(true);
+  });
+});