Easy · System Design

Log analyzer

Given log lines fed one at a time to ingest(line), return report(): a map holding TOTAL, the number of lines ingested, plus the number of lines at each level seen. A line's level is its first whitespace-separated token, upper-cased, with one trailing colon removed; blank lines have no level.

Examples

Example 1

{
  "lines": ["INFO: started", "WARN: slow query", "ERROR: timeout", "INFO: retry ok"]
}

Output: TOTAL=4, INFO=2, WARN=1, ERROR=1

Example 2

{
  "lines": ["warn: disk at 91", "", "INFO retry ok", "Warn: disk at 95", "ERROR: db: timeout"]
}

Output: TOTAL=5, WARN=2, INFO=1, ERROR=1

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