PivotHandlerServerConfigurator

config/dev.json

@@ -56,6 +56,17 @@
         "@type": "StaticAssetEntry",
         "filePath": "www/index.html"
       }
+    },
+    {
+      "comment": "Redirect to add/remove trailing slash where it helps",
+      "@type": "Override",
+      "overrideInstance": { "@id": "urn:solid-server:default:HandlerServerConfigurator" },
+      "overrideParameters": {
+        "@type": "PivotHandlerServerConfigurator",
+        "comment": "Handles all request events from the server.",
+        "handler": { "@id": "urn:solid-server:default:HttpHandler" },
+        "showStackTrace": { "@id": "urn:solid-server:default:variable:showStackTrace" }
+      }
     }
   ]
 }

config/prod.json

@@ -134,6 +134,14 @@
         "@type": "StaticAssetEntry",
         "filePath": "www/index.html"
       }
+    },
+    {
+      "comment": "Redirect to add/remove trailing slash where it helps",
+      "@type": "Override",
+      "overrideInstance": { "@id": "urn:solid-server:default:HandlerServerConfigurator" },
+      "overrideParameters": {
+        "@type": "PivotHandlerServerConfigurator"
+      }
     }
   ]
 }

config/test.json

@@ -58,6 +58,14 @@
         "@type": "StaticAssetEntry",
         "filePath": "www/index.html"
       }
+    },
+    {
+      "comment": "Redirect to add/remove trailing slash where it helps",
+      "@type": "Override",
+      "overrideInstance": { "@id": "urn:solid-server:default:HandlerServerConfigurator" },
+      "overrideParameters": {
+        "@type": "PivotHandlerServerConfigurator"
+      }
     }
   ]
 }

src/index.ts

@@ -2,3 +2,4 @@ export * from "./storage/RedirectingStore";
 export * from "./storage/RdfPatchingStore";
 export * from "./storage/patch/ThrowingN3Patcher";
 export * from './FedcmHttpHandler'
+export * from './server/PivotHandlerServerConfigurator';

src/server/PivotHandlerServerConfigurator.ts

@@ -0,0 +1,67 @@
+import type { IncomingMessage, Server, ServerResponse } from 'node:http';
+import { getLoggerFor, isError, guardStream, HttpHandler, ServerConfigurator } from '@solid/community-server';
+
+/**
+ * A {@link ServerConfigurator} that attaches an {@link HttpHandler} to the `request` event of a {@link Server}.
+ * All incoming requests will be sent to the provided handler.
+ * Failsafes are added to make sure a valid response is sent in case something goes wrong.
+ *
+ * The `showStackTrace` parameter can be used to add stack traces to error outputs.
+ */
+export class PivotHandlerServerConfigurator extends ServerConfigurator {
+  protected readonly logger = getLoggerFor(this);
+  protected readonly errorLogger = (error: Error): void => {
+    this.logger.error(`Request error: ${error.message}`);
+  };
+
+  /** The main HttpHandler */
+  private readonly handler: HttpHandler;
+  private readonly showStackTrace: boolean;
+
+  public constructor(handler: HttpHandler, showStackTrace = false) {
+    super();
+    this.handler = handler;
+    this.showStackTrace = showStackTrace;
+  }
+
+  public async handle(server: Server): Promise<void> {
+    server.on(
+      'request',
+      // eslint-disable-next-line ts/no-misused-promises
+      async(request: IncomingMessage, response: ServerResponse): Promise<void> => {
+        try {
+          this.logger.info(`Pivot received ${request.method} request for ${request.url}`);
+          const guardedRequest = guardStream(request);
+          guardedRequest.on('error', this.errorLogger);
+          await this.handler.handleSafe({ request: guardedRequest, response });
+        } catch (error: unknown) {
+          const errMsg = this.createErrorMessage(error);
+          this.logger.error(errMsg);
+          if (response.headersSent) {
+            response.end();
+          } else {
+            response.setHeader('Content-Type', 'text/plain; charset=utf-8');
+            response.writeHead(500).end(errMsg);
+          }
+        } finally {
+          if (!response.headersSent) {
+            response.writeHead(404).end();
+          }
+        }
+      },
+    );
+  }
+
+  /**
+   * Creates a readable error message based on the error and the `showStackTrace` parameter.
+   */
+  private createErrorMessage(error: unknown): string {
+    if (!isError(error)) {
+      return `Unknown error: ${error as string}.\n`;
+    }
+    if (this.showStackTrace && isError(error) && error.stack) {
+      return `${error.stack}\n`;
+    }
+    return `${error.name}: ${error.message}\n`;
+  }
+}