[FEATURE] add memory cache to @salesforce/pwa-kit-runtime/utils/ssr-c…

…onfig getConfig function SalesforceCommerceCloud#1620

packages/pwa-kit-runtime/src/utils/ssr-config.server.js

@@ -10,6 +10,8 @@ const SUPPORTED_FILE_TYPES = ['js', 'yml', 'yaml', 'json']
 
 const IS_REMOTE = Object.prototype.hasOwnProperty.call(process.env, 'AWS_LAMBDA_FUNCTION_NAME')
 
+const CONFIG_CACHE = new Map();
+
 /**
  * Returns the express app configuration file in object form. The file will be resolved in the
  * the following order:
@@ -37,6 +39,11 @@ const IS_REMOTE = Object.prototype.hasOwnProperty.call(process.env, 'AWS_LAMBDA_
 /* istanbul ignore next */
 export const getConfig = (opts = {}) => {
     const {buildDirectory} = opts
+
+    if (CONFIG_CACHE.has(buildDirectory)) {
+        return CONFIG_CACHE.get(buildDirectory);
+    }
+
     const configDirBase = IS_REMOTE ? 'build' : ''
     let targetName = process?.env?.DEPLOY_TARGET || ''
 
@@ -85,5 +92,7 @@ export const getConfig = (opts = {}) => {
         )
     }
 
+    CONFIG_CACHE.set(buildDirectory, config);
+
     return config
 }