slfmt/src/slfmt.nim

118 lines
3.5 KiB
Nim

import std/[json, options, sequtils, streams, strutils, terminal, times]
import timeutils
import docopt
from std/logging import Level
const VERSION = "0.1.2"
const USAGE = """Usage:
slfmt [options]
Options:
-h, --help Print this usage and help information
-l, --log-level <lvl> Only show log events at or above this level
-n, --namespace <ns> Only show log events from this namespace
"""
const fieldDisplayOrder = @[
"scope", "level", "ts", "code", "sid", "sub", "msg", "err", "stack", "method", "args"]
func parseLogLevel(s: string): Level =
case s.toUpper
of "DEBUG": result = Level.lvlDebug
of "INFO": result = Level.lvlInfo
of "NOTICE": result = Level.lvlNotice
of "WARN": result = Level.lvlWarn
of "ERROR": result = Level.lvlError
of "FATAL": result = Level.lvlFatal
else: result = Level.lvlAll
func decorate(
s: string,
fg = fgDefault,
style: set[Style] = {}): string =
result = ""
if style != {}:
result &= toSeq(items(style)).mapIt(ansiStyleCode(it)).join("")
if fg != fgDefault: result &= ansiForegroundColorCode(fg)
result &= s & ansiResetCode
proc formatField(name: string, value: JsonNode): string =
result = decorate(name, fgCyan) & ":" & " ".repeat(max(1, 10 - name.len))
var strVal: string = ""
case name:
of "ts":
let dt = parseIso8601(value.getStr)
strVal = decorate(dt.local.formatIso8601 & " (local) ", fgBlue, {styleBright}) &
dt.utc.formatIso8601 & " (UTC)"
of "sid", "sub": strVal = decorate(value.getStr, fgGreen)
of "err": strVal = decorate(value.getStr, fgRed)
of "msg": strVal = decorate(value.getStr, fgYellow)
of "stack": strVal = decorate(value.getStr, fgBlack, {styleBright})
else:
if value.kind == JString: strVal = decorate(value.getStr)
else: strVal = pretty(value)
let valLines = splitLines(strVal)
if name.len > 10 or strVal.len + 16 > terminalWidth() or valLines.len > 1:
result &= "\n" & valLines.mapIt(" " & it).join("\n") & "\n"
else: result &= strVal & "\n"
proc prettyPrintFormat(logJson: JsonNode): string =
result = '-'.repeat(terminalWidth()) & "\n"
# Print the known fields in order first
for f in fieldDisplayOrder:
if logJson.hasKey(f):
result &= formatField(f, logJson[f])
logJson.delete(f)
# Print the rest of the fields
for (key, val) in pairs(logJson): result &= formatField(key, val)
result &= "\n"
proc parseLogLine(logLine: string): JsonNode =
result = parseJson(logLine)
when isMainModule:
try:
let args = docopt(USAGE, version = VERSION)
let logLevel =
if args["--log-level"]: some(parseLogLevel($args["--log-level"]))
else: none[Level]()
let namespace =
if args["--namespace"]: some($args["--namespace"])
else: none[string]()
var line: string = ""
let sin = newFileStream(stdin)
while(sin.readLine(line)):
try:
let logJson = parseLogLine(line)
if logLevel.isSome and logJson.hasKey("level"):
let lvl = parseLogLevel(logJson["level"].getStr)
if lvl < logLevel.get: continue
if namespace.isSome and logJson.hasKey("scope"):
if not logJson["scope"].getStr.startsWith(namespace.get): continue
stdout.writeLine(prettyPrintFormat(logJson))
except ValueError, JsonParsingError:
stdout.writeLine(line)
except:
stderr.writeLine("slfmt - FATAL: " & getCurrentExceptionMsg())
stderr.writeLine(getCurrentException().getStackTrace())
quit(QuitFailure)