Implemented: logic to identify authorisations for the given user (#176)

package.json

@@ -15,6 +15,7 @@
     "@capacitor/android": "^2.5.0",
     "@capacitor/core": "^2.4.7",
     "@capacitor/ios": "^2.4.7",
+    "@casl/ability": "^6.0.0",
     "@hotwax/app-version-info": "^1.0.0",
     "@hotwax/apps-theme": "^1.1.0",
     "@hotwax/oms-api": "^1.6.0",
@@ -23,6 +24,7 @@
     "@ionic/vue-router": "^6.2.9",
     "axios": "^0.21.1",
     "axios-cache-adapter": "^2.7.3",
+    "boon-js": "^2.0.3",
     "core-js": "^3.6.5",
     "http-status-codes": "^2.1.4",
     "luxon": "^3.2.0",

src/authorization/Actions.ts

@@ -0,0 +1,2 @@
+export default {
+} 

src/authorization/Rules.ts

@@ -0,0 +1,7 @@
+export default {
+    "APP_UPLOAD_VIEW": "",
+    "APP_COUNT_VIEW": "",
+    "APP_SEARCH_VIEW": "",
+    "APP_ORDER_UPDATE": "COMMON_ADMIN",
+    "APP_RF_CONFIG_UPDATE": "COMMON_ADMIN"
+} as any 

src/authorization/index.ts

@@ -0,0 +1,124 @@
+import { AbilityBuilder, PureAbility } from '@casl/ability';
+import { getEvaluator, parse } from 'boon-js';
+import { Tokens } from 'boon-js/lib/types'
+
+// TODO Improve this
+// We will move this code to an external plugin and use below Actions and Rules accordlingly
+let Actions = {} as any;
+let Rules = {} as any;
+
+// We are using CASL library to define permissions.
+// Instead of using Action-Subject based authorisation we are going with Claim based Authorization.
+// We would be defining the permissions for each action and case, map with server permissiosn based upon certain rules.
+// https://casl.js.org/v5/en/cookbook/claim-authorization
+// Following the comment of Sergii Stotskyi, author of CASL
+// https://github.com/stalniy/casl/issues/525
+// We are defining a PureAbility and creating an instance with AbilityBuilder.
+type ClaimBasedAbility = PureAbility<string>;
+const { build } = new AbilityBuilder<ClaimBasedAbility>(PureAbility);
+const ability = build();
+
+/**
+ * The method returns list of permissions required for the rules. We are having set of rules, 
+ * through which app permissions are defined based upon the server permissions.
+ * When getting server permissions, as all the permissions are not be required. 
+ * Specific permissions used defining the rules are extracted and sent to server. 
+ * @returns permissions
+ */
+const getServerPermissionsFromRules = () => {
+    // Iterate for each rule
+    const permissions = Object.keys(Rules).reduce((permissions: any, rule: any) => {
+        const permissionRule = Rules[rule];
+        // some rules may be empty, no permission is required from server
+        if (permissionRule) {
+            // Each rule may have multiple permissions along with operators
+            // Boon js parse rules into tokens, each token may be operator or server permission
+            // permissionId will have token name as identifier. 
+            const permissionTokens = parse(permissionRule);
+            permissions = permissionTokens.reduce((permissions: any, permissionToken: any) => {
+                // Token object with name as identifier has permissionId 
+                if (Tokens.IDENTIFIER === permissionToken.name) {
+                    permissions.add(permissionToken.value);
+                }
+                return permissions;
+            }, permissions)
+        }
+        return permissions;
+    }, new Set())
+    return [...permissions];
+}
+
+/**
+ * The method is used to prepare app permissions from the server permissions.
+ * Rules could be defined such that each app permission could be defined based upon certain one or more server permissions.
+ * @param serverPermissions 
+ * @returns appPermissions
+ */
+const prepareAppPermissions = (serverPermissions: any) => {
+    const serverPermissionsInput = serverPermissions.reduce((serverPermissionsInput: any, permission: any) => {
+        serverPermissionsInput[permission] = true;
+        return serverPermissionsInput;
+    }, {})
+    // Boonjs evaluator needs server permissions as object with permissionId and boolean value
+    // Each rule is passed to evaluator along with the server permissions
+    // if the server permissions and rule matches, app permission is added to list
+    const permissions = Object.keys(Rules).reduce((permissions: any, rule: any) => {
+        const permissionRule = Rules[rule];
+        // If for any app permission, we have empty rule we user is assigned the permission
+        // If rule is not defined, the app permisions is still evaluated or provided to all the users.
+        if (!permissionRule || (permissionRule && getEvaluator(permissionRule)(serverPermissionsInput))) {
+            permissions.push(rule);
+        }
+        return permissions;
+    }, [])
+    const { can, rules } = new AbilityBuilder<ClaimBasedAbility>(PureAbility);
+    permissions.map((permission: any) => {
+        can(permission);
+    })
+    return rules;
+}
+
+/**
+ * 
+ * Sets the current app permissions. This should be used after perparing the app permissions from the server permissions
+ * @param permissions 
+ * @returns 
+ */
+const setPermissions = (permissions: any) => {
+    // If the user has passed undefined or null, it should not break the code
+    if (!permissions) permissions = [];
+    ability.update(permissions)
+    return true;
+};
+
+/**
+ * Resets the permissions list. Used for cases like logout 
+ */
+const resetPermissions = () => setPermissions([]);
+
+/**
+ * 
+ * @param permission 
+ * @returns 
+ */
+const hasPermission = (permission: string) => ability.can(permission);
+
+export { Actions, getServerPermissionsFromRules, hasPermission, prepareAppPermissions, resetPermissions, setPermissions};
+
+// TODO Move this code to an external plugin, to be used across the apps
+export default {
+    install(app: any, options: any) {
+
+        // Rules and Actions could be app and OMS package specific
+        Rules = options.rules;
+        Actions = options.actions;
+
+        // TODO Check why global properties is not working and apply across.
+        app.config.globalProperties.$permission = this;
+    },
+    getServerPermissionsFromRules, 
+    hasPermission, 
+    prepareAppPermissions, 
+    resetPermissions, 
+    setPermissions
+}

src/locales/en.json

@@ -42,6 +42,7 @@
   "Settings": "Settings",
   "Shopify Config": "Shopify Config",
   "Something went wrong": "Something went wrong",
+  "Something went wrong while login. Please contact administrator": "Something went wrong while login. Please contact administrator.",
   "Specify which facility you want to operate from. Order, inventory and other configuration data will be specific to the facility you select.": "Specify which facility you want to operate from. Order, inventory and other configuration data will be specific to the facility you select.",
   "Stock": "Stock",
   "Select reason": "Select reason",
@@ -61,5 +62,6 @@
   "Variance": "Variance",
   "Variance reason": "Variance reason",
   "Variance updated successfully": "Variance updated successfully",
-  "View": "View"
+  "View": "View",
+  "You do not have permission to access this page": "You do not have permission to access this page",
 }

src/main.ts

@@ -28,14 +28,21 @@ import '@hotwax/apps-theme';
 
 import i18n from './i18n'
 import store from './store'
+import permissionPlugin from '@/authorization';
+import permissionRules from '@/authorization/Rules';
+import permissionActions from '@/authorization/Actions';
 
 const app = createApp(App)
   .use(IonicVue, {
     mode: 'md'
   })
   .use(router)
   .use(i18n)
-  .use(store);
+  .use(store)
+  .use(permissionPlugin, {
+    rules: permissionRules,
+    actions: permissionActions
+  });
 
 // Filters are removed in Vue 3 and global filter introduced https://v3.vuejs.org/guide/migration/filters.html#global-filters
 app.config.globalProperties.$filters = {