DIGISTAT log files are typically generated on a daily basis and follow a standard naming convention, such as:

{SystemArea}_{yyyyMMdd}.log

Another naming format, not native but commonly used by technical support teams and often found in Jira tickets, is:

{HostName}_{SystemArea}_{yyyyMMdd}.log

Inside each file, log entries follow a well-defined structure, typically formatted as:

{HH:mm:ss}{ – }<log entry record 1>{cr}{lf}    
{HH:mm:ss}{ – }<log entry record 2>{cr}{lf}    
{HH:mm:ss}{ – }<log entry record …>{cr}{lf}    
{HH:mm:ss}{ – }<log entry record _n_>{cr}{lf}

or multi-line:

{HH:mm:ss}{ – }<log entry record 1 line 1>{cr}{lf}   
<log entry record 1 line 2>{cr}{lf}     
<log entry record 1 line …>{cr}{lf}     
<log entry record 1 line n>{cr}{lf}     
{HH:mm:ss}{ – }<log entry record 2>{cr}{lf}    
{HH:mm:ss}{ – }<log entry record …>{cr}{lf}    
{HH:mm:ss}{ – }<log entry record _n_>{cr}{lf}

To reconstruct a complete and coherent log record, it is necessary to combine information from both the file name and the content within the file.

Key elements to consider include:

• System Area (DAS3, DBv2, MessageCenter, etc.)

• File date (yyyyMMdd)

• Timestamp (HH:mm:ss)

• Log message content (both single-line and/or multi-line)

After a thorough analysis of the log files, it was possible to precisely identify the timestamp and the delimiter that separates it from the log message.

Within the log message itself, there are often one or two distinctive elements that further characterize the entry based on the system area. These elements are optional, may appear consecutively (up to two), and help to specialize the content of the log. For example:

{HH:mm:ss}{ – }<[category] log entry record …>{cr}{lf}

or

{HH:mm:ss}{ – }<[category] [sub-category] log entry record …>{cr}{lf}

These elements are useful for filtering and are referred to as tag1 and tag2.

How the Utility Works

Now that the structure of DIGISTAT log files has been clarified, we can describe how the DASLogToJSON utility functions.

This command-line tool takes a .log file that follows the expected structure and generates two output files with the same base name as the original log file:

- {SystemArea}_{yyyyMMdd}.log.json
- {SystemArea}_{yyyyMMdd}_header.log.json

The first file contains only the extracted and structured log data, these are the actual log entries.

The second file includes additional information useful for identifying the context of the log file, such as the customer name, optional descriptive notes, and other metadata relevant for traceability and analysis.

{SystemArea}_{yyyyMMdd}.log.json

[
  {
    "uniqueFileIDRef": "68552e54b3624a5c68a63c74",
    "logLevel": "TRACE",
    "hostName": "SRVDIGISTAT",
    "area": "DAS3",
    "sequence": 7,
    "dateTime": "2025-06-19T12:08:24",
    "tag1": "[UMSMessageCenterClient]",
    "tag2": "",
    "content": "[UMSMessageCenterClient] Connection to Message Center successfully, try authorization"
  },
  {
    ...
  }
]

Field	Description
uniqueFileIDRef	Unique file identifier, used to link with the corresponding header file
logLevel	Log level according to NLOG: TRACE | DEBUG | INFO | WARN | ERROR | FATAL This field will be null for DIGISTAT versions prior to 10.x, which do not implement the NLOG library
hostName	Source host name
area	Identifies the system area the log file belongs to
sequence	Sequential number, generated during import, corresponding to the line number of the log entry. Useful for sorting entries with identical HH:mm:ss timestamps
dateTime	Date and time of the log entry (derived from the file name and the timestamp in the line)
tag1	First optional tag
tag2	Second optional tag
content	Log entry full text

{SystemArea}_{yyyyMMdd}_header.log.json

{
    "uniqueFileID": "68552e54b3624a5c68a63c74",
    "customerName": "MY CUSTOMER",
    "hostName": "SRVDIGISTAT",
    "swVersion": "\u003E= 10.0.0.0",
    "nLogType": true,
    "area": "DAS3",
    "logEntriesCount": 147,
    "startTime": "2025-06-20T11:48:04.1265938+02:00",
    "elapsedTimeSeconds": 0.0106744,
    "inputFile": ".\\DAS3_20250619.log",
    "outputFile": ".\\DAS3_20250619.log.json",
    "headerFile": ".\\DAS3_20250619_header.log.json",
    "creatorHostName": "ITFLO-H725.mydomain.com",
    "creatorUserName": "MYDOMAIN\\gpancani",
    "creatorOperatingSystem": "Windows Microsoft Windows NT 10.0.19045.0",
    "creatorNotes": "My notes related my logs files and reason to collect these info"
}

Field	Description
uniqueFileIDRef	Refer to the Unique file identifier
customerName	Customer and/or System name
hostName	Source host name
swVersion	DIGISTAT software version
nLogType	true if the log was generated by NLOG
area	System Area
logEntriesCount	Number of processed log entries (not the number of lines in the file)
startTime	Timestamp marking the start of the conversion
elapsedTimeSeconds	Duration of the conversion in seconds
inputFile	Path and name of the input file
outputFile	Path and name of the output file
headerFile	Path and name of the output header file
creatorHostName	The host machine where the conversion was performed
creatorUserName	Operating system used
creatorOperatingSystem	Version of the operating system on which the conversion was executed
creatorNotes	User-defined notes, it is recommended to include the reason for the analysis and, if possible, a time-related clue

Command-Line Parameters

DASLogToJSON accepts several command-line parameters that must be provided to successfully convert the log files:

Parameter	Functionality
--logfolder	(Required) Specifies the path to the .log files that need to be converted.
--hostname	(Optional) Overrides the host name if it is not included as a prefix in the file name.
--swversion	(Optional but recommended) Indicates the software version in the format x.y.z.w such as: 9.2.3.1 or 10.0.0.1 etc. f omitted, the version will be automatically inferred as eithe: “>= 10.0.0.0” or “< 10.0.0.0”
--customername	(Optional) Specifies the name of the customer or system.
--notes	(Optional) Allows the user to add descriptive notes.
--mongodbextjson	(Optional) If set, converts the dateTime field into a MongoDB-compatible date format.

Command-Line Example

.\DASLogToJSON.exe --logfolder="X:\LogToAnalyse\Customers\UK London\Royal London Hospital" --customername="UK | London | Royal London Hospital" --hostname="srvtest01.rl.nhs.uk" --notes="acquisition stops around midnight" --mongodbextjson=no

Example of application launch

C:\GitHubRepo\DASLogToJSON\bin\Debug\net6.0>.\DASLogToJSON.exe --logfolder="F:\LogToAnalyse\Customers\UK London\Royal London Hospital" --customername="UK | London | Royal London Hospital" --hostname="srvtest01.rl.nhs.uk" --notes="acquisition stops around midnight" --mongodbextjson=no

DAS Log to JSON Converter
---------------------------------------------------
Header File F:\LogToAnalyse\Customers\UK London\Royal London Hospital\DAS3_20250626_header.log.json
Input file: F:\LogToAnalyse\Customers\UK London\Royal London Hospital\DAS3_20250626.log
Output file: F:\LogToAnalyse\Customers\UK London\Royal London Hospital\DAS3_20250626.log.json
Log entry NLog: True
Host Name: srvtest01.rl.nhs.uk
Area: DAS3
Number of log entries: 808
Unique file ID: 6874f65931f98d45cc154aae
Elapsed time: 0.0233343 seconds
---------------------------------------------------
Header File F:\LogToAnalyse\Customers\UK London\Royal London Hospital\DBv2_20250626_header.log.json
Input file: F:\LogToAnalyse\Customers\UK London\Royal London Hospital\DBv2_20250626.log
Output file: F:\LogToAnalyse\Customers\UK London\Royal London Hospital\DBv2_20250626.log.json
Log entry NLog: True
Host Name: srvtest01.rl.nhs.uk
Area: DBv2
Number of log entries: 13
Unique file ID: 6874f65931f98d45cc154ab0
Elapsed time: 0.0019599 seconds