REST /var/log reader

Some assumptions could be considered TODO items for future enhancement

• The log files are in /var/log
• The log files are uncompressed plain text files
  • Compressed or archived files (e.g. .gz, bz2, .tar, .tgz) are not supported
• The log files are sorted by timestamp (oldest first) as it is captured in each log event
• Log events are separated by a newline character
• REST response Content-Type is text/plain; charset=utf-8, regardless of the Accept request header
• All errors are returned to REST callers as HTTP status 500, even if these might be correctable by the caller
• LRU result caching of compiled regexes and search results are not implemented

• GET /api/v1/logs - Get list of all log files in /var/log that this service can read
• GET /api/v1/logs/{log} - Get the contents of the log file specified by {log} in /var/log (e.g. /api/v1/logs/messages)
  Query Parameters:
  • n - Number of lines to return (default: 25, all: 0)
  • q - Case sensitive fixed text filter to apply to each line (default: ""), more performant than r
  • r - Regex filter to apply to each line (default: .*)

• Go - Programming language
• HttpRouter - HTTP request router

• The service package contains the logic of the service, agnostic of presentation and transport
• The controller package contains the HTTP request handlers

Optionally, arbitrarily large fake log files can be generated in json or delimited format to augment any that are naturally in /var/log.

• See: GitHub mikebd/go-make-log - Generate fake application log files (e.g. as input to log processors)

• docker build -t go-read-var-log . - Build the Docker image
• docker run go-read-var-log - Run without arguments
  OR
  docker run go-read-var-log /app/go-read-var-log <args> - Run with the given arguments

• go run ./main <args> - Run the main.go file with the given arguments