Displays the current authentication mechanism in the admin panel (#981)

* Adds authentication mechanism to admin panel

Adds field to the "Security settings" admin display, showing the
currently configured authentication mechanism.

* Adds 14px margin to admin panel names

app/server/lib/BootProbes.ts

@@ -58,6 +58,7 @@ export class BootProbes {
     this._probes.push(_bootProbe);
     this._probes.push(_hostHeaderProbe);
     this._probes.push(_sandboxingProbe);
+    this._probes.push(_authenticationProbe);
     this._probeById = new Map(this._probes.map(p => [p.id, p]));
   }
 }
@@ -202,3 +203,17 @@ const _sandboxingProbe: Probe = {
     };
   },
 };
+
+const _authenticationProbe: Probe = {
+  id: 'authentication',
+  name: 'Authentication system',
+  apply: async(server, req) => {
+    const loginSystemId = server.getInfo('loginMiddlewareComment');
+    return {
+      success: loginSystemId != undefined,
+      details: {
+        loginSystemId,
+      }
+    };
+  },
+};

app/server/lib/FlexServer.ts

@@ -1426,6 +1426,11 @@ export class FlexServer implements GristServer {
     return this._sandboxInfo;
   }
 
+  public getInfo(key: string): any {
+    const infoPair = this.info.find(([keyToCheck]) => key === keyToCheck);
+    return infoPair?.[1];
+  }
+
   public disableExternalStorage() {
     if (this.deps.has('doc')) {
       throw new Error('disableExternalStorage called too late');

app/server/lib/GristServer.ts

@@ -67,6 +67,7 @@ export interface GristServer {
   getBundledWidgets(): ICustomWidget[];
   hasBoot(): boolean;
   getSandboxInfo(): SandboxInfo|undefined;
+  getInfo(key: string): any;
 }
 
 export interface GristLoginSystem {
@@ -159,6 +160,7 @@ export function createDummyGristServer(): GristServer {
     getBundledWidgets() { return []; },
     hasBoot() { return false; },
     getSandboxInfo() { return undefined; },
+    getInfo(key: string) { return undefined; }
   };
 }