fix: fix log-helper for generic exception handling

Introduce public getExceptionStack and getExceptionMessage functions
with corresponding unit tests and include the new log-helper into
api-server as usage example

Closes: hyperledger#1702
Signed-off-by: Michael Courtin <michael.courtin@accenture.com>

packages/cactus-cmd-api-server/src/main/typescript/api-server.ts

@@ -43,6 +43,7 @@ import {
   Bools,
   Logger,
   LoggerProvider,
+  LogHelper,
   Servers,
 } from "@hyperledger/cactus-common";
 
@@ -241,7 +242,8 @@ export class ApiServer {
 
       return { addressInfoCockpit, addressInfoApi, addressInfoGrpc };
     } catch (ex) {
-      const errorMessage = `Failed to start ApiServer: ${ex.stack}`;
+      const stack = LogHelper.getExceptionStack(ex);
+      const errorMessage = `Failed to start ApiServer: ${stack}`;
       this.log.error(errorMessage);
       this.log.error(`Attempting shutdown...`);
       try {
@@ -296,9 +298,10 @@ export class ApiServer {
         await this.getPluginImportsCount(),
       );
       return this.pluginRegistry;
-    } catch (e) {
+    } catch (ex) {
       this.pluginRegistry = new PluginRegistry({ plugins: [] });
-      const errorMessage = `Failed init PluginRegistry: ${e.stack}`;
+      const stack = LogHelper.getExceptionStack(ex);
+      const errorMessage = `Failed init PluginRegistry: ${stack}`;
       this.log.error(errorMessage);
       throw new Error(errorMessage);
     }

packages/cactus-common/src/main/typescript/logging/log-helper.ts

@@ -1,7 +1,7 @@
 export class LogHelper {
-  static getExceptionStack(exception: unknown): string {
+  public static getExceptionStack(exception: unknown): string {
     // handle unknown exception input
-    const defaultStack = "";
+    const defaultStack = "NO_STACK_INFORMATION_INCLUDED_IN_EXCEPTION";
     const invalidStack = "INVALID_STACK_INFORMATION";
     let stack = defaultStack;
 
@@ -26,9 +26,9 @@ export class LogHelper {
     return stack;
   }
 
-  static getExceptionMessage(exception: unknown): string {
+  public static getExceptionMessage(exception: unknown): string {
     // handle unknown exception input
-    const defaultMessage = "";
+    const defaultMessage = "NO_MESSAGE_INCLUDED_IN_EXCEPTION";
     const invalidMessage = "INVALID_EXCEPTION_MESSAGE";
     let message = defaultMessage;
 

packages/cactus-common/src/main/typescript/public-api.ts

@@ -1,4 +1,5 @@
 export { LoggerProvider } from "./logging/logger-provider";
+export { LogHelper } from "./logging/log-helper";
 export { Logger, ILoggerOptions } from "./logging/logger";
 export { LogLevelDesc } from "loglevel";
 export { Objects } from "./objects";