feat: add prom metric for total custom root roles in use (#4438)

https://linear.app/unleash/issue/2-1311/add-a-new-prometheus-metric-with-custom-root-roles-in-use

As a follow-up to #4435, this PR
adds a metric for total custom root roles in use by at least one entity:
users, service accounts, groups.

`custom_root_roles_in_use_total`

Output from `http://localhost:4242/internal-backstage/prometheus`:

```
# HELP process_cpu_user_seconds_total Total user CPU time spent in seconds.
# TYPE process_cpu_user_seconds_total counter
process_cpu_user_seconds_total 0.060755

# HELP process_cpu_system_seconds_total Total system CPU time spent in seconds.
# TYPE process_cpu_system_seconds_total counter
process_cpu_system_seconds_total 0.01666

# HELP process_cpu_seconds_total Total user and system CPU time spent in seconds.
# TYPE process_cpu_seconds_total counter
process_cpu_seconds_total 0.077415

# HELP process_start_time_seconds Start time of the process since unix epoch in seconds.
# TYPE process_start_time_seconds gauge
process_start_time_seconds 1691420275

# HELP process_resident_memory_bytes Resident memory size in bytes.
# TYPE process_resident_memory_bytes gauge
process_resident_memory_bytes 199196672

# HELP nodejs_eventloop_lag_seconds Lag of event loop in seconds.
# TYPE nodejs_eventloop_lag_seconds gauge
nodejs_eventloop_lag_seconds 0

# HELP nodejs_eventloop_lag_min_seconds The minimum recorded event loop delay.
# TYPE nodejs_eventloop_lag_min_seconds gauge
nodejs_eventloop_lag_min_seconds 0.009076736

# HELP nodejs_eventloop_lag_max_seconds The maximum recorded event loop delay.
# TYPE nodejs_eventloop_lag_max_seconds gauge
nodejs_eventloop_lag_max_seconds 0.037683199

# HELP nodejs_eventloop_lag_mean_seconds The mean of the recorded event loop delays.
# TYPE nodejs_eventloop_lag_mean_seconds gauge
nodejs_eventloop_lag_mean_seconds 0.011063251638989169

# HELP nodejs_eventloop_lag_stddev_seconds The standard deviation of the recorded event loop delays.
# TYPE nodejs_eventloop_lag_stddev_seconds gauge
nodejs_eventloop_lag_stddev_seconds 0.0013618102764025837

# HELP nodejs_eventloop_lag_p50_seconds The 50th percentile of the recorded event loop delays.
# TYPE nodejs_eventloop_lag_p50_seconds gauge
nodejs_eventloop_lag_p50_seconds 0.011051007

# HELP nodejs_eventloop_lag_p90_seconds The 90th percentile of the recorded event loop delays.
# TYPE nodejs_eventloop_lag_p90_seconds gauge
nodejs_eventloop_lag_p90_seconds 0.011321343

# HELP nodejs_eventloop_lag_p99_seconds The 99th percentile of the recorded event loop delays.
# TYPE nodejs_eventloop_lag_p99_seconds gauge
nodejs_eventloop_lag_p99_seconds 0.013688831

# HELP nodejs_active_resources Number of active resources that are currently keeping the event loop alive, grouped by async resource type.
# TYPE nodejs_active_resources gauge
nodejs_active_resources{type="FSReqCallback"} 1
nodejs_active_resources{type="TTYWrap"} 3
nodejs_active_resources{type="TCPSocketWrap"} 5
nodejs_active_resources{type="TCPServerWrap"} 1
nodejs_active_resources{type="Timeout"} 1
nodejs_active_resources{type="Immediate"} 1

# HELP nodejs_active_resources_total Total number of active resources.
# TYPE nodejs_active_resources_total gauge
nodejs_active_resources_total 12

# HELP nodejs_active_handles Number of active libuv handles grouped by handle type. Every handle type is C++ class name.
# TYPE nodejs_active_handles gauge
nodejs_active_handles{type="WriteStream"} 2
nodejs_active_handles{type="ReadStream"} 1
nodejs_active_handles{type="Socket"} 5
nodejs_active_handles{type="Server"} 1

# HELP nodejs_active_handles_total Total number of active handles.
# TYPE nodejs_active_handles_total gauge
nodejs_active_handles_total 9

# HELP nodejs_active_requests Number of active libuv requests grouped by request type. Every request type is C++ class name.
# TYPE nodejs_active_requests gauge
nodejs_active_requests{type="FSReqCallback"} 1

# HELP nodejs_active_requests_total Total number of active requests.
# TYPE nodejs_active_requests_total gauge
nodejs_active_requests_total 1

# HELP nodejs_heap_size_total_bytes Process heap size from Node.js in bytes.
# TYPE nodejs_heap_size_total_bytes gauge
nodejs_heap_size_total_bytes 118587392

# HELP nodejs_heap_size_used_bytes Process heap size used from Node.js in bytes.
# TYPE nodejs_heap_size_used_bytes gauge
nodejs_heap_size_used_bytes 89642552

# HELP nodejs_external_memory_bytes Node.js external memory size in bytes.
# TYPE nodejs_external_memory_bytes gauge
nodejs_external_memory_bytes 1601594

# HELP nodejs_heap_space_size_total_bytes Process heap space size total from Node.js in bytes.
# TYPE nodejs_heap_space_size_total_bytes gauge
nodejs_heap_space_size_total_bytes{space="read_only"} 0
nodejs_heap_space_size_total_bytes{space="old"} 70139904
nodejs_heap_space_size_total_bytes{space="code"} 3588096
nodejs_heap_space_size_total_bytes{space="map"} 2899968
nodejs_heap_space_size_total_bytes{space="large_object"} 7258112
nodejs_heap_space_size_total_bytes{space="code_large_object"} 1146880
nodejs_heap_space_size_total_bytes{space="new_large_object"} 0
nodejs_heap_space_size_total_bytes{space="new"} 33554432

# HELP nodejs_heap_space_size_used_bytes Process heap space size used from Node.js in bytes.
# TYPE nodejs_heap_space_size_used_bytes gauge
nodejs_heap_space_size_used_bytes{space="read_only"} 0
nodejs_heap_space_size_used_bytes{space="old"} 66992120
nodejs_heap_space_size_used_bytes{space="code"} 2892640
nodejs_heap_space_size_used_bytes{space="map"} 2519280
nodejs_heap_space_size_used_bytes{space="large_object"} 7026824
nodejs_heap_space_size_used_bytes{space="code_large_object"} 983200
nodejs_heap_space_size_used_bytes{space="new_large_object"} 0
nodejs_heap_space_size_used_bytes{space="new"} 9236136

# HELP nodejs_heap_space_size_available_bytes Process heap space size available from Node.js in bytes.
# TYPE nodejs_heap_space_size_available_bytes gauge
nodejs_heap_space_size_available_bytes{space="read_only"} 0
nodejs_heap_space_size_available_bytes{space="old"} 1898360
nodejs_heap_space_size_available_bytes{space="code"} 7328
nodejs_heap_space_size_available_bytes{space="map"} 327888
nodejs_heap_space_size_available_bytes{space="large_object"} 0
nodejs_heap_space_size_available_bytes{space="code_large_object"} 0
nodejs_heap_space_size_available_bytes{space="new_large_object"} 16495616
nodejs_heap_space_size_available_bytes{space="new"} 7259480

# HELP nodejs_version_info Node.js version info.
# TYPE nodejs_version_info gauge
nodejs_version_info{version="v18.16.0",major="18",minor="16",patch="0"} 1

# HELP nodejs_gc_duration_seconds Garbage collection duration by kind, one of major, minor, incremental or weakcb.
# TYPE nodejs_gc_duration_seconds histogram

# HELP http_request_duration_milliseconds App response time
# TYPE http_request_duration_milliseconds summary

# HELP db_query_duration_seconds DB query duration time
# TYPE db_query_duration_seconds summary
db_query_duration_seconds{quantile="0.1",store="api-tokens",action="getAllActive"} 0.03091475
db_query_duration_seconds{quantile="0.5",store="api-tokens",action="getAllActive"} 0.03091475
db_query_duration_seconds{quantile="0.9",store="api-tokens",action="getAllActive"} 0.03091475
db_query_duration_seconds{quantile="0.95",store="api-tokens",action="getAllActive"} 0.03091475
db_query_duration_seconds{quantile="0.99",store="api-tokens",action="getAllActive"} 0.03091475
db_query_duration_seconds_sum{store="api-tokens",action="getAllActive"} 0.03091475
db_query_duration_seconds_count{store="api-tokens",action="getAllActive"} 1

# HELP feature_toggle_update_total Number of times a toggle has been updated. Environment label would be "n/a" when it is not available, e.g. when a feature toggle is created.
# TYPE feature_toggle_update_total counter

# HELP feature_toggle_usage_total Number of times a feature toggle has been used
# TYPE feature_toggle_usage_total counter

# HELP feature_toggles_total Number of feature toggles
# TYPE feature_toggles_total gauge
feature_toggles_total{version="5.3.0"} 31

# HELP users_total Number of users
# TYPE users_total gauge
users_total 1011

# HELP projects_total Number of projects
# TYPE projects_total gauge
projects_total 4

# HELP environments_total Number of environments
# TYPE environments_total gauge
environments_total 10

# HELP groups_total Number of groups
# TYPE groups_total gauge
groups_total 5

# HELP roles_total Number of roles
# TYPE roles_total gauge
roles_total 11

# HELP custom_root_roles_total Number of custom root roles
# TYPE custom_root_roles_total gauge
custom_root_roles_total 3

# HELP custom_root_roles_in_use_total Number of custom root roles in use
# TYPE custom_root_roles_in_use_total gauge
custom_root_roles_in_use_total 2

# HELP segments_total Number of segments
# TYPE segments_total gauge
segments_total 5

# HELP context_total Number of context
# TYPE context_total gauge
context_total 7

# HELP strategies_total Number of strategies
# TYPE strategies_total gauge
strategies_total 5

# HELP client_apps_total Number of registered client apps aggregated by range by last seen
# TYPE client_apps_total gauge
client_apps_total{range="allTime"} 0
client_apps_total{range="30d"} 0
client_apps_total{range="7d"} 0

# HELP saml_enabled Whether SAML is enabled
# TYPE saml_enabled gauge
saml_enabled 1

# HELP oidc_enabled Whether OIDC is enabled
# TYPE oidc_enabled gauge
oidc_enabled 0

# HELP client_sdk_versions Which sdk versions are being used
# TYPE client_sdk_versions counter

# HELP optimal_304_diffing Count the Optimal 304 diffing with status
# TYPE optimal_304_diffing counter

# HELP db_pool_min Minimum DB pool size
# TYPE db_pool_min gauge
db_pool_min 0

# HELP db_pool_max Maximum DB pool size
# TYPE db_pool_max gauge
db_pool_max 4

# HELP db_pool_free Current free connections in DB pool
# TYPE db_pool_free gauge
db_pool_free 0

# HELP db_pool_used Current connections in use in DB pool
# TYPE db_pool_used gauge
db_pool_used 4

# HELP db_pool_pending_creates how many asynchronous create calls are running in DB pool
# TYPE db_pool_pending_creates gauge
db_pool_pending_creates 0

# HELP db_pool_pending_acquires how many acquires are waiting for a resource to be released in DB pool
# TYPE db_pool_pending_acquires gauge
db_pool_pending_acquires 24
```

frontend/src/component/admin/instance-privacy/InstancePrivacy.tsx

@@ -44,6 +44,8 @@ const featureCollectionDetails = {
         Roles: 'The number of custom roles defined in your instance',
         'Custom Root Roles':
             'The number of custom root roles defined in your instance',
+        'Custom Root Roles In Use':
+            'The number of custom root roles that are in use by entities (users, groups, service accounts)',
         Environments: 'The number of environments in your instance',
         Segments: 'The number of segments defined in your instance',
         Strategies: 'The number of strategies defined in your instance',

src/lib/db/role-store.ts

@@ -64,6 +64,19 @@ export default class RoleStore implements IRoleStore {
             .then((res) => Number(res[0].count));
     }
 
+    async filteredCountInUse(filter: Partial<RoleSchema>): Promise<number> {
+        return this.db
+            .from(T.ROLES)
+            .countDistinct('roles.id')
+            .leftJoin('role_user as ru', 'roles.id', 'ru.role_id')
+            .leftJoin('groups as g', 'roles.id', 'g.root_role_id')
+            .where(filter)
+            .andWhere((qb) =>
+                qb.whereNotNull('ru.role_id').orWhereNotNull('g.root_role_id'),
+            )
+            .then((res) => Number(res[0].count));
+    }
+
     async create(role: ICustomRoleInsert): Promise<ICustomRole> {
         const row = await this.db(T.ROLES)
             .insert({

src/lib/metrics.ts

@@ -109,6 +109,11 @@ export default class MetricsMonitor {
             help: 'Number of custom root roles',
         });
 
+        const customRootRolesInUseTotal = new client.Gauge({
+            name: 'custom_root_roles_in_use_total',
+            help: 'Number of custom root roles in use',
+        });
+
         const segmentsTotal = new client.Gauge({
             name: 'segments_total',
             help: 'Number of segments',
@@ -177,6 +182,9 @@ export default class MetricsMonitor {
                 customRootRolesTotal.reset();
                 customRootRolesTotal.set(stats.customRootRoles);
 
+                customRootRolesInUseTotal.reset();
+                customRootRolesInUseTotal.set(stats.customRootRolesInUse);
+
                 segmentsTotal.reset();
                 segmentsTotal.set(stats.segments);
 

src/lib/routes/admin-api/instance-admin.ts

@@ -99,7 +99,8 @@ class InstanceAdminController extends Controller {
             instanceId: 'ed3861ae-78f9-4e8c-8e57-b57efc15f82b',
             projects: 1,
             roles: 5,
-            customRootRoles: 1,
+            customRootRoles: 2,
+            customRootRolesInUse: 1,
             segments: 2,
             strategies: 8,
             sum: 'some-sha256-hash',

src/lib/services/instance-stats-service.ts

@@ -33,6 +33,7 @@ export interface InstanceStats {
     contextFields: number;
     roles: number;
     customRootRoles: number;
+    customRootRolesInUse: number;
     featureExports: number;
     featureImports: number;
     groups: number;
@@ -180,6 +181,7 @@ export class InstanceStatsService {
             groups,
             roles,
             customRootRoles,
+            customRootRolesInUse,
             environments,
             segments,
             strategies,
@@ -196,6 +198,7 @@ export class InstanceStatsService {
             this.groupStore.count(),
             this.roleStore.count(),
             this.roleStore.filteredCount({ type: CUSTOM_ROOT_ROLE_TYPE }),
+            this.roleStore.filteredCountInUse({ type: CUSTOM_ROOT_ROLE_TYPE }),
             this.environmentStore.count(),
             this.segmentStore.count(),
             this.strategyStore.count(),
@@ -217,6 +220,7 @@ export class InstanceStatsService {
             contextFields,
             roles,
             customRootRoles,
+            customRootRolesInUse,
             groups,
             environments,
             segments,

src/lib/services/version-service.ts

@@ -229,6 +229,7 @@ export default class VersionService {
             groups,
             roles,
             customRootRoles,
+            customRootRolesInUse,
             environments,
             segments,
             strategies,
@@ -248,6 +249,7 @@ export default class VersionService {
             this.roleStore.filteredCount({
                 type: CUSTOM_ROOT_ROLE_TYPE,
             }),
+            this.roleStore.filteredCountInUse({ type: CUSTOM_ROOT_ROLE_TYPE }),
             this.environmentStore.count(),
             this.segmentStore.count(),
             this.strategyStore.count(),
@@ -269,6 +271,7 @@ export default class VersionService {
             groups,
             roles,
             customRootRoles,
+            customRootRolesInUse,
             environments,
             segments,
             strategies,

src/lib/types/stores/role-store.ts

@@ -31,4 +31,5 @@ export interface IRoleStore extends Store<ICustomRole, number> {
     nameInUse(name: string, existingId?: number): Promise<boolean>;
     count(): Promise<number>;
     filteredCount(filter: Partial<RoleSchema>): Promise<number>;
+    filteredCountInUse(filter: Partial<RoleSchema>): Promise<number>;
 }

src/test/fixtures/fake-role-store.ts

@@ -17,6 +17,10 @@ export default class FakeRoleStore implements IRoleStore {
         return Promise.resolve(0);
     }
 
+    filteredCountInUse(search: Partial<RoleSchema>): Promise<number> {
+        return Promise.resolve(0);
+    }
+
     roles: ICustomRole[] = [];
 
     getGroupRolesForProject(projectId: string): Promise<IRole[]> {