From 2c68cda0e76b3d206a96bdedfd294639e6e18e88 Mon Sep 17 00:00:00 2001
From: Brandon Istenes <bistenes@gmail.com>
Date: Fri, 14 Jul 2023 13:19:07 -0400
Subject: [PATCH 1/2] O3-2258: Extension system support for feature flags

---
 .../framework/esm-extensions/package.json     |  2 +
 .../esm-extensions/src/extensions.ts          | 21 +++++--
 .../framework/esm-extensions/src/store.ts     |  2 +
 packages/framework/esm-framework/docs/API.md  | 25 ++++----
 .../docs/interfaces/AssignedExtension.md      | 25 +++++---
 .../docs/interfaces/ConnectedExtension.md     |  8 +--
 .../docs/interfaces/ExtensionRegistration.md  | 11 ++++
 .../docs/interfaces/ExtensionSlotState.md     |  4 +-
 .../docs/interfaces/ExtensionStore.md         |  2 +-
 .../docs/interfaces/OpenmrsAppRoutes.md       |  8 +--
 .../docs/interfaces/ResourceLoader.md         |  2 +-
 packages/framework/esm-globals/src/types.ts   |  6 +-
 .../__mocks__/openmrs-esm-state.mock.ts       | 17 ++++++
 .../esm-react-utils/src/extensions.test.tsx   | 59 ++++++++++++++++++-
 .../src/useConnectedExtensions.ts             | 19 +++++-
 packages/shell/esm-app-shell/src/apps.ts      |  1 +
 yarn.lock                                     |  2 +
 17 files changed, 173 insertions(+), 41 deletions(-)

diff --git a/packages/framework/esm-extensions/package.json b/packages/framework/esm-extensions/package.json
index aeddcf0cd..051078404 100644
--- a/packages/framework/esm-extensions/package.json
+++ b/packages/framework/esm-extensions/package.json
@@ -39,12 +39,14 @@
   "peerDependencies": {
     "@openmrs/esm-api": "5.x",
     "@openmrs/esm-config": "5.x",
+    "@openmrs/esm-feature-flags": "5.x",
     "@openmrs/esm-state": "5.x",
     "single-spa": "5.x"
   },
   "devDependencies": {
     "@openmrs/esm-api": "^5.0.2",
     "@openmrs/esm-config": "^5.0.2",
+    "@openmrs/esm-feature-flags": "^5.0.2",
     "@openmrs/esm-state": "^5.0.2",
     "single-spa": "^5.9.2"
   },
diff --git a/packages/framework/esm-extensions/src/extensions.ts b/packages/framework/esm-extensions/src/extensions.ts
index a6ce435c8..a1717fbf8 100644
--- a/packages/framework/esm-extensions/src/extensions.ts
+++ b/packages/framework/esm-extensions/src/extensions.ts
@@ -19,6 +19,7 @@ import {
   getExtensionSlotConfigFromStore,
   getExtensionSlotsConfigStore,
 } from "@openmrs/esm-config";
+import { featureFlagsStore } from "@openmrs/esm-feature-flags";
 import isEqual from "lodash-es/isEqual";
 import isUndefined from "lodash-es/isUndefined";
 import {
@@ -282,16 +283,27 @@ function getOrder(
  *
  * @param assignedExtensions The list of extensions to filter.
  * @param online Whether the app is currently online. If `null`, uses `navigator.onLine`.
+ * @param enabledFeatureFlags The names of all enabled feature flags. If `null`, looks
+ *    up the feature flags using the feature flags API.
  * @returns A list of extensions that should be rendered
  */
 export function getConnectedExtensions(
   assignedExtensions: Array<AssignedExtension>,
-  online: boolean | null = null
+  online: boolean | null = null,
+  enabledFeatureFlags: Array<string> | null = null
 ): Array<ConnectedExtension> {
   const isOnline = online ?? navigator.onLine;
-  return assignedExtensions.filter((e) =>
-    checkStatusFor(isOnline, e.online, e.offline)
-  );
+  const featureFlags =
+    enabledFeatureFlags ??
+    Object.entries(featureFlagsStore.getState().flags)
+      .filter(([, { enabled }]) => enabled)
+      .map(([name]) => name);
+  return assignedExtensions
+    .filter((e) => checkStatusFor(isOnline, e.online, e.offline))
+    .filter(
+      (e) =>
+        e.featureFlag === undefined || featureFlags?.includes(e.featureFlag)
+    );
 }
 
 function getAssignedExtensionsFromSlotData(
@@ -343,6 +355,7 @@ function getAssignedExtensionsFromSlotData(
         name,
         moduleName: extension.moduleName,
         config: extensionConfig,
+        featureFlag: extension.featureFlag,
         meta: extension.meta,
       });
     }
diff --git a/packages/framework/esm-extensions/src/store.ts b/packages/framework/esm-extensions/src/store.ts
index a673b7ce8..4e3d7af99 100644
--- a/packages/framework/esm-extensions/src/store.ts
+++ b/packages/framework/esm-extensions/src/store.ts
@@ -22,6 +22,7 @@ export interface ExtensionRegistration {
   online?: boolean;
   offline?: boolean;
   privileges?: string | Array<string>;
+  featureFlag?: string;
 }
 
 export interface ExtensionInfo extends ExtensionRegistration {
@@ -81,6 +82,7 @@ export interface AssignedExtension {
   config: ConfigObject | null;
   online?: boolean | object;
   offline?: boolean | object;
+  featureFlag?: string;
 }
 
 export interface ConnectedExtension {
diff --git a/packages/framework/esm-framework/docs/API.md b/packages/framework/esm-framework/docs/API.md
index 6c16d0543..8d6a173e8 100644
--- a/packages/framework/esm-framework/docs/API.md
+++ b/packages/framework/esm-framework/docs/API.md
@@ -405,7 +405,7 @@ ___
 
 ### ExtensionDefinition
 
-Ƭ **ExtensionDefinition**: { `meta?`: { `[k: string]`: `unknown`;  } ; `name`: `string` ; `offline?`: `boolean` ; `online?`: `boolean` ; `order?`: `number` ; `privileges?`: `string` \| `string`[] ; `slot?`: `string` ; `slots?`: `string`[]  } & { `component`: `string`  } \| { `component?`: `never`  }
+Ƭ **ExtensionDefinition**: { `featureFlag?`: `string` ; `meta?`: { `[k: string]`: `unknown`;  } ; `name`: `string` ; `offline?`: `boolean` ; `online?`: `boolean` ; `order?`: `number` ; `privileges?`: `string` \| `string`[] ; `slot?`: `string` ; `slots?`: `string`[]  } & { `component`: `string`  } \| { `component?`: `never`  }
 
 A definition of an extension as extracted from an app's routes.json
 
@@ -444,7 +444,7 @@ Basically, this is the same as the app routes, with each routes definition keyed
 
 #### Defined in
 
-[packages/framework/esm-globals/src/types.ts:251](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-globals/src/types.ts#L251)
+[packages/framework/esm-globals/src/types.ts:255](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-globals/src/types.ts#L255)
 
 ___
 
@@ -2257,7 +2257,7 @@ writing a module for a specific implementation.
 
 #### Defined in
 
-[packages/framework/esm-extensions/src/extensions.ts:174](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/extensions.ts#L174)
+[packages/framework/esm-extensions/src/extensions.ts:175](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/extensions.ts#L175)
 
 ___
 
@@ -2280,7 +2280,7 @@ Avoid using this. Extension attachments should be considered declarative.
 
 #### Defined in
 
-[packages/framework/esm-extensions/src/extensions.ts:205](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/extensions.ts#L205)
+[packages/framework/esm-extensions/src/extensions.ts:206](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/extensions.ts#L206)
 
 ___
 
@@ -2302,7 +2302,7 @@ Avoid using this. Extension attachments should be considered declarative.
 
 #### Defined in
 
-[packages/framework/esm-extensions/src/extensions.ts:229](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/extensions.ts#L229)
+[packages/framework/esm-extensions/src/extensions.ts:230](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/extensions.ts#L230)
 
 ___
 
@@ -2326,13 +2326,13 @@ An array of extensions assigned to the named slot
 
 #### Defined in
 
-[packages/framework/esm-extensions/src/extensions.ts:360](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/extensions.ts#L360)
+[packages/framework/esm-extensions/src/extensions.ts:373](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/extensions.ts#L373)
 
 ___
 
 ### getConnectedExtensions
 
-▸ **getConnectedExtensions**(`assignedExtensions`, `online?`): [`ConnectedExtension`](interfaces/ConnectedExtension.md)[]
+▸ **getConnectedExtensions**(`assignedExtensions`, `online?`, `enabledFeatureFlags?`): [`ConnectedExtension`](interfaces/ConnectedExtension.md)[]
 
 Filters a list of extensions according to whether they support the
 current connectivity status.
@@ -2343,6 +2343,7 @@ current connectivity status.
 | :------ | :------ | :------ | :------ |
 | `assignedExtensions` | [`AssignedExtension`](interfaces/AssignedExtension.md)[] | `undefined` | The list of extensions to filter. |
 | `online` | ``null`` \| `boolean` | `null` | Whether the app is currently online. If `null`, uses `navigator.onLine`. |
+| `enabledFeatureFlags` | ``null`` \| `string`[] | `null` | The names of all enabled feature flags. If `null`, looks    up the feature flags using the feature flags API. |
 
 #### Returns
 
@@ -2352,7 +2353,7 @@ A list of extensions that should be rendered
 
 #### Defined in
 
-[packages/framework/esm-extensions/src/extensions.ts:287](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/extensions.ts#L287)
+[packages/framework/esm-extensions/src/extensions.ts:290](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/extensions.ts#L290)
 
 ___
 
@@ -2384,7 +2385,7 @@ getExtensionNameFromId("baz")
 
 #### Defined in
 
-[packages/framework/esm-extensions/src/extensions.ts:118](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/extensions.ts#L118)
+[packages/framework/esm-extensions/src/extensions.ts:119](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/extensions.ts#L119)
 
 ___
 
@@ -2401,7 +2402,7 @@ state of the extension system.
 
 #### Defined in
 
-[packages/framework/esm-extensions/src/store.ts:130](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L130)
+[packages/framework/esm-extensions/src/store.ts:132](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L132)
 
 ___
 
@@ -2487,7 +2488,7 @@ ___
 ▸ **useConnectedExtensions**(`slotName`): [`ConnectedExtension`](interfaces/ConnectedExtension.md)[]
 
 Gets the assigned extension for a given extension slot name.
-Considers if offline or online.
+Considers if offline or online, and what feature flags are enabled.
 
 #### Parameters
 
@@ -2501,7 +2502,7 @@ Considers if offline or online.
 
 #### Defined in
 
-[packages/framework/esm-react-utils/src/useConnectedExtensions.ts:15](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-react-utils/src/useConnectedExtensions.ts#L15)
+[packages/framework/esm-react-utils/src/useConnectedExtensions.ts:17](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-react-utils/src/useConnectedExtensions.ts#L17)
 
 ___
 
diff --git a/packages/framework/esm-framework/docs/interfaces/AssignedExtension.md b/packages/framework/esm-framework/docs/interfaces/AssignedExtension.md
index 90c58bf62..b1622679c 100644
--- a/packages/framework/esm-framework/docs/interfaces/AssignedExtension.md
+++ b/packages/framework/esm-framework/docs/interfaces/AssignedExtension.md
@@ -7,6 +7,7 @@
 ### Extension Properties
 
 - [config](AssignedExtension.md#config)
+- [featureFlag](AssignedExtension.md#featureflag)
 - [id](AssignedExtension.md#id)
 - [meta](AssignedExtension.md#meta)
 - [moduleName](AssignedExtension.md#modulename)
@@ -24,7 +25,17 @@ The extension's config. Note that this will be `null` until the slot is mounted.
 
 #### Defined in
 
-[packages/framework/esm-extensions/src/store.ts:81](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L81)
+[packages/framework/esm-extensions/src/store.ts:82](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L82)
+
+___
+
+### featureFlag
+
+• `Optional` **featureFlag**: `string`
+
+#### Defined in
+
+[packages/framework/esm-extensions/src/store.ts:85](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L85)
 
 ___
 
@@ -34,7 +45,7 @@ ___
 
 #### Defined in
 
-[packages/framework/esm-extensions/src/store.ts:76](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L76)
+[packages/framework/esm-extensions/src/store.ts:77](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L77)
 
 ___
 
@@ -44,7 +55,7 @@ ___
 
 #### Defined in
 
-[packages/framework/esm-extensions/src/store.ts:79](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L79)
+[packages/framework/esm-extensions/src/store.ts:80](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L80)
 
 ___
 
@@ -54,7 +65,7 @@ ___
 
 #### Defined in
 
-[packages/framework/esm-extensions/src/store.ts:78](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L78)
+[packages/framework/esm-extensions/src/store.ts:79](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L79)
 
 ___
 
@@ -64,7 +75,7 @@ ___
 
 #### Defined in
 
-[packages/framework/esm-extensions/src/store.ts:77](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L77)
+[packages/framework/esm-extensions/src/store.ts:78](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L78)
 
 ___
 
@@ -74,7 +85,7 @@ ___
 
 #### Defined in
 
-[packages/framework/esm-extensions/src/store.ts:83](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L83)
+[packages/framework/esm-extensions/src/store.ts:84](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L84)
 
 ___
 
@@ -84,4 +95,4 @@ ___
 
 #### Defined in
 
-[packages/framework/esm-extensions/src/store.ts:82](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L82)
+[packages/framework/esm-extensions/src/store.ts:83](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L83)
diff --git a/packages/framework/esm-framework/docs/interfaces/ConnectedExtension.md b/packages/framework/esm-framework/docs/interfaces/ConnectedExtension.md
index 502d042c1..21d92ac2f 100644
--- a/packages/framework/esm-framework/docs/interfaces/ConnectedExtension.md
+++ b/packages/framework/esm-framework/docs/interfaces/ConnectedExtension.md
@@ -21,7 +21,7 @@ The extension's config. Note that this will be `null` until the slot is mounted.
 
 #### Defined in
 
-[packages/framework/esm-extensions/src/store.ts:91](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L91)
+[packages/framework/esm-extensions/src/store.ts:93](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L93)
 
 ___
 
@@ -31,7 +31,7 @@ ___
 
 #### Defined in
 
-[packages/framework/esm-extensions/src/store.ts:87](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L87)
+[packages/framework/esm-extensions/src/store.ts:89](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L89)
 
 ___
 
@@ -41,7 +41,7 @@ ___
 
 #### Defined in
 
-[packages/framework/esm-extensions/src/store.ts:89](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L89)
+[packages/framework/esm-extensions/src/store.ts:91](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L91)
 
 ___
 
@@ -51,4 +51,4 @@ ___
 
 #### Defined in
 
-[packages/framework/esm-extensions/src/store.ts:88](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L88)
+[packages/framework/esm-extensions/src/store.ts:90](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L90)
diff --git a/packages/framework/esm-framework/docs/interfaces/ExtensionRegistration.md b/packages/framework/esm-framework/docs/interfaces/ExtensionRegistration.md
index b2fa0b30a..d1b90c3bd 100644
--- a/packages/framework/esm-framework/docs/interfaces/ExtensionRegistration.md
+++ b/packages/framework/esm-framework/docs/interfaces/ExtensionRegistration.md
@@ -6,6 +6,7 @@
 
 ### Extension Properties
 
+- [featureFlag](ExtensionRegistration.md#featureflag)
 - [meta](ExtensionRegistration.md#meta)
 - [moduleName](ExtensionRegistration.md#modulename)
 - [name](ExtensionRegistration.md#name)
@@ -20,6 +21,16 @@
 
 ## Extension Properties
 
+### featureFlag
+
+• `Optional` **featureFlag**: `string`
+
+#### Defined in
+
+[packages/framework/esm-extensions/src/store.ts:25](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L25)
+
+___
+
 ### meta
 
 • **meta**: [`ExtensionMeta`](ExtensionMeta.md)
diff --git a/packages/framework/esm-framework/docs/interfaces/ExtensionSlotState.md b/packages/framework/esm-framework/docs/interfaces/ExtensionSlotState.md
index 4eee1caea..7aa12d6a7 100644
--- a/packages/framework/esm-framework/docs/interfaces/ExtensionSlotState.md
+++ b/packages/framework/esm-framework/docs/interfaces/ExtensionSlotState.md
@@ -17,7 +17,7 @@
 
 #### Defined in
 
-[packages/framework/esm-extensions/src/store.ts:72](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L72)
+[packages/framework/esm-extensions/src/store.ts:73](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L73)
 
 ___
 
@@ -27,4 +27,4 @@ ___
 
 #### Defined in
 
-[packages/framework/esm-extensions/src/store.ts:71](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L71)
+[packages/framework/esm-extensions/src/store.ts:72](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L72)
diff --git a/packages/framework/esm-framework/docs/interfaces/ExtensionStore.md b/packages/framework/esm-framework/docs/interfaces/ExtensionStore.md
index 38b564b97..ac468a615 100644
--- a/packages/framework/esm-framework/docs/interfaces/ExtensionStore.md
+++ b/packages/framework/esm-framework/docs/interfaces/ExtensionStore.md
@@ -16,4 +16,4 @@
 
 #### Defined in
 
-[packages/framework/esm-extensions/src/store.ts:67](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L67)
+[packages/framework/esm-extensions/src/store.ts:68](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-extensions/src/store.ts#L68)
diff --git a/packages/framework/esm-framework/docs/interfaces/OpenmrsAppRoutes.md b/packages/framework/esm-framework/docs/interfaces/OpenmrsAppRoutes.md
index d100314a3..7e5d26f98 100644
--- a/packages/framework/esm-framework/docs/interfaces/OpenmrsAppRoutes.md
+++ b/packages/framework/esm-framework/docs/interfaces/OpenmrsAppRoutes.md
@@ -23,7 +23,7 @@ A list of backend modules necessary for this frontend module and the correspondi
 
 #### Defined in
 
-[packages/framework/esm-globals/src/types.ts:236](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-globals/src/types.ts#L236)
+[packages/framework/esm-globals/src/types.ts:240](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-globals/src/types.ts#L240)
 
 ___
 
@@ -35,7 +35,7 @@ An array of all extensions supported by this frontend module. Extensions can be
 
 #### Defined in
 
-[packages/framework/esm-globals/src/types.ts:244](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-globals/src/types.ts#L244)
+[packages/framework/esm-globals/src/types.ts:248](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-globals/src/types.ts#L248)
 
 ___
 
@@ -47,7 +47,7 @@ An array of all pages supported by this frontend module. Pages are automatically
 
 #### Defined in
 
-[packages/framework/esm-globals/src/types.ts:240](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-globals/src/types.ts#L240)
+[packages/framework/esm-globals/src/types.ts:244](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-globals/src/types.ts#L244)
 
 ___
 
@@ -59,4 +59,4 @@ The version of this frontend module.
 
 #### Defined in
 
-[packages/framework/esm-globals/src/types.ts:232](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-globals/src/types.ts#L232)
+[packages/framework/esm-globals/src/types.ts:236](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-globals/src/types.ts#L236)
diff --git a/packages/framework/esm-framework/docs/interfaces/ResourceLoader.md b/packages/framework/esm-framework/docs/interfaces/ResourceLoader.md
index 1b1fbb1f3..bfecb107e 100644
--- a/packages/framework/esm-framework/docs/interfaces/ResourceLoader.md
+++ b/packages/framework/esm-framework/docs/interfaces/ResourceLoader.md
@@ -20,4 +20,4 @@
 
 #### Defined in
 
-[packages/framework/esm-globals/src/types.ts:254](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-globals/src/types.ts#L254)
+[packages/framework/esm-globals/src/types.ts:258](https://github.com/openmrs/openmrs-esm-core/blob/main/packages/framework/esm-globals/src/types.ts#L258)
diff --git a/packages/framework/esm-globals/src/types.ts b/packages/framework/esm-globals/src/types.ts
index dfaa18c3b..fba68a5a6 100644
--- a/packages/framework/esm-globals/src/types.ts
+++ b/packages/framework/esm-globals/src/types.ts
@@ -190,9 +190,13 @@ export type ExtensionDefinition = {
    */
   order?: number;
   /**
-  
+   * The user must have ANY of these privileges to see this extension.
    */
   privileges?: string | Array<string>;
+  /**
+   * If supplied, the extension will only be rendered when this feature flag is enabled.
+   */
+  featureFlag?: string;
   /**
    * Meta describes any properties that are passed down to the extension when it is loaded
    */
diff --git a/packages/framework/esm-react-utils/__mocks__/openmrs-esm-state.mock.ts b/packages/framework/esm-react-utils/__mocks__/openmrs-esm-state.mock.ts
index a059abdc9..bb34b7d98 100644
--- a/packages/framework/esm-react-utils/__mocks__/openmrs-esm-state.mock.ts
+++ b/packages/framework/esm-react-utils/__mocks__/openmrs-esm-state.mock.ts
@@ -62,6 +62,23 @@ export function getGlobalStore<T>(
   return instrumentedStore(name, available.value);
 }
 
+export function subscribeTo<T, U>(
+  store: StoreApi<T>,
+  select: (state: T) => U,
+  handle: (subState: U) => void
+) {
+  let previous = select(store.getState());
+
+  return store.subscribe((state) => {
+    const current = select(state);
+
+    if (current !== previous) {
+      previous = current;
+      handle(current);
+    }
+  });
+}
+
 function instrumentedStore<T>(name: string, store: StoreApi<T>) {
   return {
     getState: jest.spyOn(store, "getState"),
diff --git a/packages/framework/esm-react-utils/src/extensions.test.tsx b/packages/framework/esm-react-utils/src/extensions.test.tsx
index 42c62ed10..9e61a8918 100644
--- a/packages/framework/esm-react-utils/src/extensions.test.tsx
+++ b/packages/framework/esm-react-utils/src/extensions.test.tsx
@@ -1,5 +1,5 @@
 import React, { useCallback, useReducer } from "react";
-import { render, screen, waitFor, within } from "@testing-library/react";
+import { act, render, screen, waitFor, within } from "@testing-library/react";
 import {
   attach,
   ConnectedExtension,
@@ -16,6 +16,10 @@ import {
   ExtensionData,
 } from ".";
 import userEvent from "@testing-library/user-event";
+import {
+  registerFeatureFlag,
+  setFeatureFlag,
+} from "@openmrs/esm-feature-flags";
 
 // For some reason in the text context `isEqual` always returns true
 // when using the import substitution in jest.config.js. Here's a custom
@@ -293,13 +297,63 @@ describe("ExtensionSlot, Extension, and useExtensionSlotMeta", () => {
       "Hindi"
     );
   });
+
+  test("Extensions behind feature flags only render when their feature flag is enabled", async () => {
+    registerSimpleExtension("Arabic", "esm-languages-app");
+    registerSimpleExtension(
+      "Turkish",
+      "esm-languages-app",
+      undefined,
+      undefined,
+      "turkic"
+    );
+    registerSimpleExtension(
+      "Turkmeni",
+      "esm-languages-app",
+      undefined,
+      undefined,
+      "turkic"
+    );
+    registerSimpleExtension(
+      "Kurmanji",
+      "esm-languages-app",
+      undefined,
+      undefined,
+      "kurdish"
+    );
+    attach("Box", "Arabic");
+    attach("Box", "Turkish");
+    attach("Box", "Turkmeni");
+    attach("Box", "Kurmanji");
+    registerFeatureFlag("turkic", "", "");
+    registerFeatureFlag("kurdish", "", "");
+    setFeatureFlag("turkic", true);
+    const App = openmrsComponentDecorator({
+      moduleName: "esm-languages-app",
+      featureName: "Languages",
+      disableTranslations: true,
+    })(() => <ExtensionSlot name="Box" />);
+    render(<App />);
+
+    await waitFor(() =>
+      expect(screen.getByText(/Turkmeni/)).toBeInTheDocument()
+    );
+    expect(screen.getByText("Arabic")).toBeInTheDocument();
+    expect(screen.getByText("Turkish")).toBeInTheDocument();
+    expect(screen.queryByText("Kurmanji")).not.toBeInTheDocument();
+    act(() => setFeatureFlag("kurdish", true));
+    await waitFor(() =>
+      expect(screen.getByText("Kurmanji")).toBeInTheDocument()
+    );
+  });
 });
 
 function registerSimpleExtension(
   name: string,
   moduleName: string,
   Component?: React.ComponentType<any>,
-  meta: object = {}
+  meta: object = {},
+  featureFlag?: string
 ) {
   const SimpleComponent = () => <div>{name}</div>;
   registerExtension({
@@ -311,5 +365,6 @@ function registerSimpleExtension(
       disableTranslations: true,
     }),
     meta,
+    featureFlag,
   });
 }
diff --git a/packages/framework/esm-react-utils/src/useConnectedExtensions.ts b/packages/framework/esm-react-utils/src/useConnectedExtensions.ts
index abd260fbe..992c10b52 100644
--- a/packages/framework/esm-react-utils/src/useConnectedExtensions.ts
+++ b/packages/framework/esm-react-utils/src/useConnectedExtensions.ts
@@ -6,10 +6,12 @@ import {
 } from "@openmrs/esm-extensions";
 import { useConnectivity } from "./useConnectivity";
 import { useAssignedExtensions } from "./useAssignedExtensions";
+import { useStore } from "./useStore";
+import { featureFlagsStore } from "@openmrs/esm-feature-flags";
 
 /**
  * Gets the assigned extension for a given extension slot name.
- * Considers if offline or online.
+ * Considers if offline or online, and what feature flags are enabled.
  * @param slotName The name of the slot to get the assigned extensions for.
  */
 export function useConnectedExtensions(
@@ -17,10 +19,21 @@ export function useConnectedExtensions(
 ): Array<ConnectedExtension> {
   const online = useConnectivity();
   const assignedExtensions = useAssignedExtensions(slotName);
+  const featureFlagStore = useStore(featureFlagsStore);
+
+  const enabledFeatureFlags = useMemo(() => {
+    return Object.entries(featureFlagStore.flags)
+      .filter(([, { enabled }]) => enabled)
+      .map(([name]) => name);
+  }, [featureFlagStore.flags]);
 
   const connectedExtensions = useMemo(() => {
-    return getConnectedExtensions(assignedExtensions, online);
-  }, [assignedExtensions, online]);
+    return getConnectedExtensions(
+      assignedExtensions,
+      online,
+      enabledFeatureFlags
+    );
+  }, [assignedExtensions, online, enabledFeatureFlags]);
 
   return connectedExtensions;
 }
diff --git a/packages/shell/esm-app-shell/src/apps.ts b/packages/shell/esm-app-shell/src/apps.ts
index d6c85c00f..253fec3fb 100644
--- a/packages/shell/esm-app-shell/src/apps.ts
+++ b/packages/shell/esm-app-shell/src/apps.ts
@@ -318,6 +318,7 @@ supported, so the extension will not be loaded.`
     privileges: extension.privileges,
     online: extension.online,
     offline: extension.offline,
+    featureFlag: extension.featureFlag,
   });
 
   for (const slot of slots) {
diff --git a/yarn.lock b/yarn.lock
index 5afa2b8a3..1fb4e8510 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3664,12 +3664,14 @@ __metadata:
   dependencies:
     "@openmrs/esm-api": ^5.0.2
     "@openmrs/esm-config": ^5.0.2
+    "@openmrs/esm-feature-flags": ^5.0.2
     "@openmrs/esm-state": ^5.0.2
     lodash-es: ^4.17.21
     single-spa: ^5.9.2
   peerDependencies:
     "@openmrs/esm-api": 5.x
     "@openmrs/esm-config": 5.x
+    "@openmrs/esm-feature-flags": 5.x
     "@openmrs/esm-state": 5.x
     single-spa: 5.x
   languageName: unknown

From 38329b38f1c35baab79dc1c89d90dc02ca659af9 Mon Sep 17 00:00:00 2001
From: Brandon Istenes <bistenes@gmail.com>
Date: Mon, 17 Jul 2023 13:05:46 -0400
Subject: [PATCH 2/2] Hail Mary

---
 .../src/integration-tests/extension-config.test.tsx             | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/framework/esm-framework/src/integration-tests/extension-config.test.tsx b/packages/framework/esm-framework/src/integration-tests/extension-config.test.tsx
index 37c232619..a2a14157a 100644
--- a/packages/framework/esm-framework/src/integration-tests/extension-config.test.tsx
+++ b/packages/framework/esm-framework/src/integration-tests/extension-config.test.tsx
@@ -253,8 +253,8 @@ describe("Interaction between configuration and extension systems", () => {
     });
 
     await waitFor(() => {
-      expect(screen.queryByText("green")).not.toBeInTheDocument();
       expect(screen.getByTestId("slot")).toHaveTextContent(/black/);
+      expect(screen.queryByText("green")).not.toBeInTheDocument();
     });
   });