fix: return 404 instead of 500 for missing collections

- Replace string rejection with TaxiiNotFoundException in repository
- Remove Promise constructor anti-pattern in findOne method
- Add debug logging for collection lookups
- Update JSDoc to document exception behavior

The /collections/{id} endpoint now correctly returns a 404 status
when a collection is not found in the database, rather than a 500
internal server error.

src/common/exceptions/taxii-exception.filter.ts

@@ -1,7 +1,6 @@
 import {
   ArgumentsHost,
   ExceptionFilter,
-  HttpException,
   Logger,
 } from "@nestjs/common";
 import { Response } from "express";
@@ -12,61 +11,60 @@ import {
   RequestContextModel,
 } from "../middleware/request-context";
 
-// @Catch(MyException) => can set to only catch specific exception types!
 export class TaxiiExceptionFilter implements ExceptionFilter {
-  private readonly logger: Logger = new Logger();
+  private readonly logger: Logger = new Logger(TaxiiExceptionFilter.name);
 
   /**
    * Handles uncaught exceptions. Any exceptions which are caught that are not a subclass of TaxiiErrorException are
    * transformed to instances of TaxiiInternalServerErrorException and returned to the user.
-   * @param exception The uncaught exception instance that triggered the TaxiiExceptionFilter
-   * @param host Provides access to the HTTP context so that the Request and Response objects can be worked upon
+   * @param exception The uncaught exception instance that triggered the filter
+   * @param host Provides access to the HTTP context
    */
-  catch(exception: HttpException, host: ArgumentsHost): any {
+  catch(exception: unknown, host: ArgumentsHost): any {
     const ctx = host.switchToHttp();
     const response = ctx.getResponse<Response>();
     const reqCtx: RequestContext = RequestContextModel.get();
+    const requestId = reqCtx?.["x-request-id"] || "unknown";
 
+    // Log the exception type and details
     this.logger.error(
-      `[${reqCtx["x-request-id"]}] The exception type is: ${
-        exception.constructor.name
-      }. The exception is ${JSON.stringify(exception)}`
+      `[${requestId}] Exception occurred: ${exception?.constructor?.name || typeof exception}`
     );
 
-    // Send a generic 500 error for any uncaught exceptions
-    if (!(exception instanceof TaxiiErrorException)) {
-      this.logger.error(
-        `[${reqCtx["x-request-id"]}] Received an unhandled exception. Please investigate the root cause of the exception triggered by request: ${reqCtx["x-request-id"]}`
-      );
-      this.logger.error(
-        `[${reqCtx["x-request-id"]}] The error is ${exception.stack.toString()}`
-      );
-      const internalServerError: TaxiiInternalServerErrorException =
-        new TaxiiInternalServerErrorException({
-          title: "Internal Error",
-          description:
-            "An unexpected error has occurred. Please contact the TAXII server administrator.",
-          // errorId: request['x-request-id'].toString(),
-          errorId: reqCtx["x-request-id"].toString(),
-        });
+    if (typeof exception === 'string') {
+      this.logger.error(`[${requestId}] String exception: ${exception}`);
+    } else if (exception instanceof Error) {
+      this.logger.error(`[${requestId}] Error details: ${exception.message}`);
+      if (exception.stack) {
+        this.logger.error(`[${requestId}] Stack trace: ${exception.stack}`);
+      }
+    } else {
+      try {
+        this.logger.error(
+          `[${requestId}] Exception details: ${JSON.stringify(exception)}`
+        );
+      } catch (e) {
+        this.logger.error(
+          `[${requestId}] Could not stringify exception: ${e.message}`
+        );
+      }
+    }
 
-      // Send the error
-      response
-        .status(TaxiiInternalServerErrorException.httpStatus)
-        .json(internalServerError);
+    // Handle TAXII exceptions
+    if (exception instanceof TaxiiErrorException) {
+      exception.errorId = requestId.toString();
+      return response.status(exception.httpStatus).json(exception);
     }
 
-    // The else clause is triggered only if the exception type if one of the custom Taxii exception classes, in
-    // which case all we want to do is set the errorId field then return the exception.
-    else {
-      // Copy the request's unique ID onto the outgoing response body
-      exception.errorId = reqCtx["x-request-id"].toString();
+    // For all other exceptions (including strings, non-HTTP errors, etc.)
+    const internalServerError = new TaxiiInternalServerErrorException({
+      title: "Internal Error",
+      description: "An unexpected error has occurred. Please contact the TAXII server administrator.",
+      errorId: requestId.toString(),
+    });
 
-      // Send the error
-      response
-        //.set('id', request['id'])
-        .status(exception.httpStatus)
-        .json(exception);
-    }
+    return response
+      .status(TaxiiInternalServerErrorException.httpStatus)
+      .json(internalServerError);
   }
-}
+}

src/taxii/providers/collection/collection.repository.ts

@@ -7,7 +7,7 @@ import {
   TaxiiCollectionDocument,
 } from "src/hydrate/schema";
 import { Model } from "mongoose";
-import { isNull } from "lodash";
+import { TaxiiNotFoundException } from "src/common/exceptions";
 
 @Injectable()
 export class CollectionRepository {
@@ -24,9 +24,11 @@ export class CollectionRepository {
    * 
    * @param id TAXII/STIX ID of the collection
    * @returns Promise resolving to TaxiiCollectionDto
-   * @throws If collection is not found
+   * @throws TaxiiNotFoundException if collection is not found
    */
   async findOne(id: string): Promise<TaxiiCollectionDto> {
+    this.logger.debug(`Searching for collection with ID: ${id}`);
+
     // Uses taxii_collection_lookup index
     const response: TaxiiCollectionEntity = await this.collectionModel
       .findOne({
@@ -35,12 +37,14 @@ export class CollectionRepository {
       })
       .exec();
 
-    return new Promise((resolve, reject) => {
-      if (!isNull(response)) {
-        resolve(new TaxiiCollectionDto({ ...response["_doc"] }));
-      }
-      reject(`Collection ID '${id}' not available in database`);
-    });
+    if (!response) {
+      throw new TaxiiNotFoundException({
+        title: "Collection Not Found",
+        description: `Collection ID '${id}' not available in database`,
+      });
+    }
+
+    return new TaxiiCollectionDto({ ...response["_doc"] });
   }
 
   /**