chore(streamlog): optimise polling mechanism

src/utils/fetchLogByChunks.ts

@@ -14,18 +14,36 @@ export const fetchLogByChunks = async (
   accessToken: string,
   logUrl: string,
   logCount: number
+): Promise<string> => {
+  return await fetchLog(requestClient, accessToken, logUrl, 0, logCount)
+}
+
+/**
+ * Fetches a section of the log file delineated by start and end lines
+ * @param {object} requestClient - client object of Request Client.
+ * @param {string} accessToken - an access token for an authorized user.
+ * @param {string} logUrl - url of the log file.
+ * @param {number} start - the line at which to start fetching the log.
+ * @param {number} end - the line at which to stop fetching the log.
+ * @returns an string containing log lines.
+ */
+export const fetchLog = async (
+  requestClient: RequestClient,
+  accessToken: string,
+  logUrl: string,
+  start: number,
+  end: number
 ): Promise<string> => {
   const logger = process.logger || console
 
   let log: string = ''
 
-  const loglimit = logCount < 10000 ? logCount : 10000
-  let start = 0
+  const loglimit = end < 10000 ? end : 10000
   do {
     logger.info(
       `Fetching logs from line no: ${start + 1} to ${
         start + loglimit
-      } of ${logCount}.`
+      } of ${end}.`
     )
     const logChunkJson = await requestClient!
       .get<any>(`${logUrl}?start=${start}&limit=${loglimit}`, accessToken)
@@ -40,6 +58,6 @@ export const fetchLogByChunks = async (
     log += logChunk
 
     start += loglimit
-  } while (start < logCount)
+  } while (start < end)
   return log
 }