From ff2da177e2addaf3e58175c7cb8bf7d01d9d786b Mon Sep 17 00:00:00 2001
From: Joe Portner <5295965+jportner@users.noreply.github.com>
Date: Tue, 7 Jan 2020 16:19:39 -0500
Subject: [PATCH] Update Boolean to coerce strings to boolean values

---
 .../kbn-config-schema/src/internals/index.ts   | 18 +++++++++++++++++-
 .../__snapshots__/boolean_type.test.ts.snap    |  4 ++++
 .../src/types/boolean_type.test.ts             | 11 +++++++++++
 3 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/packages/kbn-config-schema/src/internals/index.ts b/packages/kbn-config-schema/src/internals/index.ts
index 4d5091eaa09b13..044c3050f9fa87 100644
--- a/packages/kbn-config-schema/src/internals/index.ts
+++ b/packages/kbn-config-schema/src/internals/index.ts
@@ -82,7 +82,23 @@ export const internals = Joi.extend([
     base: Joi.boolean(),
     coerce(value: any, state: State, options: ValidationOptions) {
       // If value isn't defined, let Joi handle default value if it's defined.
-      if (value !== undefined && typeof value !== 'boolean') {
+      if (value === undefined) {
+        return value;
+      }
+
+      // Allow strings 'true' and 'false' to be coerced to booleans (case-insensitive).
+
+      // From Joi docs on `Joi.boolean`:
+      // > Generates a schema object that matches a boolean data type. Can also
+      // >  be called via bool(). If the validation convert option is on
+      // > (enabled by default), a string (either "true" or "false") will be
+      // converted to a boolean if specified.
+      if (typeof value === 'string') {
+        const normalized = value.toLowerCase();
+        value = normalized === 'true' ? true : normalized === 'false' ? false : value;
+      }
+
+      if (typeof value !== 'boolean') {
         return this.createError('boolean.base', { value }, state, options);
       }
 
diff --git a/packages/kbn-config-schema/src/types/__snapshots__/boolean_type.test.ts.snap b/packages/kbn-config-schema/src/types/__snapshots__/boolean_type.test.ts.snap
index c3f33dc29bf50e..0e5f6de2deea8f 100644
--- a/packages/kbn-config-schema/src/types/__snapshots__/boolean_type.test.ts.snap
+++ b/packages/kbn-config-schema/src/types/__snapshots__/boolean_type.test.ts.snap
@@ -9,3 +9,7 @@ exports[`returns error when not boolean 1`] = `"expected value of type [boolean]
 exports[`returns error when not boolean 2`] = `"expected value of type [boolean] but got [Array]"`;
 
 exports[`returns error when not boolean 3`] = `"expected value of type [boolean] but got [string]"`;
+
+exports[`returns error when not boolean 4`] = `"expected value of type [boolean] but got [number]"`;
+
+exports[`returns error when not boolean 5`] = `"expected value of type [boolean] but got [string]"`;
diff --git a/packages/kbn-config-schema/src/types/boolean_type.test.ts b/packages/kbn-config-schema/src/types/boolean_type.test.ts
index d6e274f05e3ffa..24a0fe2f62b1dc 100644
--- a/packages/kbn-config-schema/src/types/boolean_type.test.ts
+++ b/packages/kbn-config-schema/src/types/boolean_type.test.ts
@@ -23,6 +23,13 @@ test('returns value by default', () => {
   expect(schema.boolean().validate(true)).toBe(true);
 });
 
+test('handles boolean strings', () => {
+  expect(schema.boolean().validate('true')).toBe(true);
+  expect(schema.boolean().validate('TRUE')).toBe(true);
+  expect(schema.boolean().validate('false')).toBe(false);
+  expect(schema.boolean().validate('FALSE')).toBe(false);
+});
+
 test('is required by default', () => {
   expect(() => schema.boolean().validate(undefined)).toThrowErrorMatchingSnapshot();
 });
@@ -49,4 +56,8 @@ test('returns error when not boolean', () => {
   expect(() => schema.boolean().validate([1, 2, 3])).toThrowErrorMatchingSnapshot();
 
   expect(() => schema.boolean().validate('abc')).toThrowErrorMatchingSnapshot();
+
+  expect(() => schema.boolean().validate(0)).toThrowErrorMatchingSnapshot();
+
+  expect(() => schema.boolean().validate('no')).toThrowErrorMatchingSnapshot();
 });