feat: add support for log aggregators

src/common.ts

@@ -47,6 +47,20 @@ export interface SSLFilePaths {
   dhparam: string;
 }
 
+/**
+ * Supported log formats for config
+ */
+type SupportedLogFormatsKeys = 'default' | 'combined' | 'json';
+
+/**
+ * Map supported formats to stings used in template view
+ */
+export const SupportedLogFormats: {[key in SupportedLogFormatsKeys]: string} = {
+  default: 'combined',
+  combined: 'combined',
+  json: 'json',
+};
+
 /**
  * A representation of the config file
  */
@@ -59,10 +73,14 @@ export interface ConfigFile {
    * List of hidden routes
    */
   hiddenRoutes: string[];
+  /**
+   * Sets log format (default or json)
+   */
+  logFormat: SupportedLogFormatsKeys;
   /**
    * Enables metrics on /metrics route
    */
-  metrics: boolean;
+  metrics?: boolean;
   /**
    * List of outdated versions
    */
@@ -97,6 +115,14 @@ export interface TemplateView {
    * Listener
    */
   listener: string;
+  /**
+   * Log format to use
+   */
+  logFormat: string;
+  /**
+   * Custom Log formatters
+   */
+  logFormatters: string;
   /**
    * Local server with listener for /metrics route
    */

src/main.ts

@@ -26,6 +26,7 @@ import {
   protocolHardeningParameters,
   SSLFilePaths,
   sslHardeningParameters,
+  SupportedLogFormats,
   TemplateView,
 } from './common';
 
@@ -244,11 +245,14 @@ ${protocolHardeningParameters}
 /**
  * Reads predefined server entry with metrics location
  */
-export async function generateMetricsServer(enableMetrics: boolean): Promise<string> {
+export async function generateMetricsServer(logFormat: string, enableMetrics?: boolean): Promise<string> {
   if (!enableMetrics) {
     return '';
   }
-  return asyncReadFile('./fixtures/metrics.template', 'utf8');
+
+  return renderTemplate(path.join('fixtures', 'metrics.template'), {
+    logFormat: logFormat,
+  });
 }
 
 /**
@@ -302,6 +306,13 @@ export async function getTemplateView(containers: Dockerode.ContainerInfo[]): Pr
     });
   });
 
+  const logFormattingPromise = renderTemplate(path.join('fixtures', 'logFormatters.template'), {});
+
+  const logFormat =
+    configFile.logFormat in SupportedLogFormats
+      ? SupportedLogFormats[configFile.logFormat]
+      : SupportedLogFormats.default;
+
   return {
     dockerVersionMap: await generateUpstreamMap(
       configFile.activeVersions,
@@ -310,7 +321,9 @@ export async function getTemplateView(containers: Dockerode.ContainerInfo[]): Pr
     ),
     hiddenRoutes: (await Promise.all(hiddenRoutesPromises)).join(''),
     listener: generateListener(configFile.sslFilePaths),
-    metrics: await generateMetricsServer(configFile.metrics),
+    logFormat: logFormat,
+    logFormatters: await logFormattingPromise,
+    metrics: await generateMetricsServer(logFormat, configFile.metrics),
     rateLimitAllowList: generateRateLimitAllowList(configFile.rateLimitAllowList),
     staticRoute: await renderTemplate(path.join('fixtures', 'staticRoute.template'), {cors}),
     visibleRoutes: (await Promise.all(visibleRoutesPromises)).join(''),