GTMS-3.md

GTMS-3

Server Templates Logging

Problem that solved by this standard

Server GTM does not have a standard format for output logs. And there is no common way to log Requests and Responses. This creates issues for log parsing and monitoring.

Standard description

• Each log line must be a valid JSON object. (This allows parse logs by ELK, CloudWatch, Loki, etc.)
• Each log object must contain at least: Type, Name and TraceId fields.
• Field Type must contain one of these values Request, Response, Message. Witch helps easily filter logs.
• TraceId must contain a unique identifier of the current incoming request. This field is used for stitching all logs done by all tags/clients during one request. Highly recommend using the trace-id header for this, as a lot of clouds/platforms use it for tracing.
• Field Name must contain tag name.

Example Code

const traceId = loggingEnabled ? getRequestHeader('trace-id') : undefined;
const isLoggingEnabled = determinateIsLoggingEnabled();
const postUrl = 'https://example.com';
const postBody = {'data': 'some data'};

log({
 'Name': 'Example',
 'Type': 'Request',
 'TraceId': traceId,
 'EventName': 'purchase',
 'RequestMethod': 'POST',
 'RequestUrl': postUrl,
 'RequestBody': postBody,
});

sendHttpRequest(postUrl, (statusCode, headers, body) => {
log({
   'Name': 'Example',
   'Type': 'Response',
   'TraceId': traceId,
   'EventName': makeString(data.conversionActionId),
   'ResponseStatusCode': statusCode,
   'ResponseHeaders': headers,
   'ResponseBody': body,
});
}, {method: 'POST'}, JSON.stringify(postBody));


function log(logObject) {
 if (isLoggingEnabled) {
   logToConsole(JSON.stringify(logObject));
 }
}

function determinateIsLoggingEnabled() {
   const containerVersion = getContainerVersion();
   const isDebug = !!(
       containerVersion &&
       (containerVersion.debugMode || containerVersion.previewMode)
   );

   if (!data.logType) {
       return isDebug;
   }

   if (data.logType === 'no') {
       return false;
   }

   if (data.logType === 'debug') {
       return isDebug;
   }

   return data.logType === 'always';
}

Example UI

{
  "displayName": "Logs Settings",
  "name": "logsGroup",
  "groupStyle": "ZIPPY_CLOSED",
  "type": "GROUP",
  "subParams": [
    {
      "type": "RADIO",
      "name": "logType",
      "radioItems": [
        {
          "value": "no",
          "displayValue": "Do not log"
        },
        {
          "value": "debug",
          "displayValue": "Log to console during debug and preview"
        },
        {
          "value": "always",
          "displayValue": "Always log to console"
        }
      ],
      "simpleValueType": true,
      "defaultValue": "debug"
    }
  ]
}

Thanks

@adatzer @paulboocock @jurajfrank