Merge pull request #1867 from oracle-devrel/witold-swierzy-patch-6

Update README.md

Author: JesusGitHubOracle

data-platform/autonomous-database/autonomous-json/MongoDBReplay/README.md

@@ -25,14 +25,21 @@ See [LICENSE](https://github.com/oracle-devrel/technology-engineering/blob/main/
 ## Usage
 1. Generic requirements
    - MR_CONFIG_DIR variable has to be set to a directory, where configuration and log files are/will be stored
+   - JDK 21 (it can be Oracle or OpenJDK)
+   - Oracle JDK can be downloaded from the following link: https://www.oracle.com/java/technologies/downloads/#java21
+   - OpenJDK is usually available in a Linux packates repository, but also can be downloaded and installed independly from the following link: https://openjdk.org/
 
 1.MDBExtractor
   requirements:
   - Source MongoDB instance up and running
   - Profiling at the MongoDB instance 
      - to extract data from traditional Mongod log file, there is need to enable logging so called slow operations at the Mongod instance level. It can be done by executing the following command:
 
-     db.setProfilingLevel(0, -1)
+     	db.setProfilingLevel(0, -1)
+      - to extract data from db.system.profile collection or its dump there is need to enable traditional profiling, by executing the following command:
+      
+        db.setProfilingLevel(2)
+        
   - The following configuration file $MR_CONFIG_DIR/MDBExtractConfig.json needs to be existing with the following parameters
 
     OUTPUT_DIR             : optional; points to directory where output files will be created;
@@ -41,6 +48,12 @@ See [LICENSE](https://github.com/oracle-devrel/technology-engineering/blob/main/
     INPUT_FILE             : optional; points to an input log file generated by a MongoDB Instance with profiling enabled
                              if this parameter is not set, then MDBExtractor will read data from standard input
 
+    INPUT_FILE_FORMAT	   : optional; provides information about from which file the data will be read. It accepts two values
+    				MONGO_LOG : in that case Extractor will be reading data from traditional Mongod log file. Profiling needs to be set to (0,-1)
+    				MONGO_PROFILE : in that case Extractor will be reading data from dump of db.system.profile collection. Profiling needs to be set to (2)
+
+    INPUT_CONNECT_STRING   : optional; if set then it points to a MongoDB instance, from which input data will be read directly. Profiling needs to be set to (2). When this parameter is set, then INPUT_FILE and INPUT_FILE_FORMAT cannot be set.
+
     COMMANDS_LOGGING       : optional; default value "true", if set to "true" then every command found by the extractor will be 
                              additional logged with console.log(...). Useful, when output will be processed by mongosh tool, which
                              has limited capabilities related to error reporting. When set to "false" only commands will be reported.