sets up argument parsing with docopt

codexcrawler.nim

@@ -2,6 +2,8 @@ import pkg/chronicles
 import pkg/chronos
 
 import ./codexcrawler/main
+import ./codexcrawler/config
+
 when defined(posix):
   import system/ansi_c
 
@@ -15,9 +17,12 @@ type
     status: ApplicationStatus
 
 proc run(app: Application) =
+  let config = parseConfig()
+  info "Loaded configuration", config
+
   app.status = ApplicationStatus.Running
 
-  waitFor runApplication()
+  waitFor startApplication()
 
   while app.status == ApplicationStatus.Running:
     try:

codexcrawler.nimble

@@ -21,6 +21,7 @@ requires "stint#3236fa68394f1e3a06e2bc34218aacdd2d675923"
 requires "https://github.com/codex-storage/nim-datastore >= 0.1.0 & < 0.2.0"
 requires "questionable >= 0.10.15 & < 0.11.0"
 requires "https://github.com/codex-storage/nim-codex-dht#4bd3a39e0030f8ee269ef217344b6b59ec2be6dc" # 7 Jan 2024 - Support for Nim 2.0.14
+requires "docopt >= 0.7.1 & < 1.0.0"
 
 task test, "Run tests":
   exec "nimble install -d -y"

codexcrawler/config.nim

@@ -0,0 +1,49 @@
+import std/net
+import ./version
+
+let doc = """
+Codex Network Crawler. Generates network metrics.
+
+Usage:
+  codexcrawler [--logLevel=<l>] [--metricsAddress=<ip>] [--metricsPort=<p>] [--dataDir=<dir>] [--discoveryPort=<p>]
+
+Options:
+  --logLevel=<l>          Sets log level [default: TRACE]
+  --metricsAddress=<ip>   Listen address of the metrics server [default: 127.0.0.1]
+  --metricsPort=<p>       Listen HTTP port of the metrics server [default: 8008]
+  --dataDir=<dir>         Directory for storing data [default: crawler_data]
+  --discoveryPort=<p>     Port used for DHT [default: 8090]
+"""
+
+import strutils
+import docopt
+
+type
+  CrawlerConfig* = ref object
+    logLevel*: string
+    metricsAddress*: IpAddress
+    metricsPort*: Port
+    dataDir*: string
+    discPort*: Port
+
+proc `$`*(config: CrawlerConfig): string =
+  "CrawlerConfig:" &
+    " logLevel=" & config.logLevel &
+    " metricsAddress=" & $config.metricsAddress &
+    " metricsPort=" & $config.metricsPort &
+    " dataDir=" & config.dataDir &
+    " discPort=" & $config.discPort
+
+proc parseConfig*(): CrawlerConfig =
+  let args = docopt(doc, version = crawlerFullVersion)
+
+  proc get(name: string): string =
+    $args[name]
+
+  return CrawlerConfig(
+    logLevel: get("--logLevel"),
+    metricsAddress: parseIpAddress(get("--metricsAddress")),
+    metricsPort: Port(parseInt(get("--metricsPort"))),
+    dataDir: get("--dataDir"),
+    discPort: Port(parseInt(get("--discoveryPort"))),
+  )

codexcrawler/logging.nim

@@ -0,0 +1,18 @@
+import pkg/chronicles
+import pkg/chronicles/helpers
+import pkg/chronicles/topics_registry
+
+proc updateLogLevel*(logLevel: string) {.upraises: [ValueError].} =
+  let directives = logLevel.split(";")
+  try:
+    setLogLevel(parseEnum[LogLevel](directives[0].toUpperAscii))
+  except ValueError:
+    raise (ref ValueError)(
+      msg:
+        "Please specify one of: trace, debug, " & "info, notice, warn, error or fatal"
+    )
+
+  if directives.len > 1:
+    for topicName, settings in parseTopicDirectives(directives[1 ..^ 1]):
+      if not setTopicState(topicName, settings.state, settings.logLevel):
+        warn "Unrecognized logging topic", topic = topicName

codexcrawler/main.nim

@@ -4,7 +4,7 @@ import pkg/chronos
 logScope:
   topics = "main"
 
-proc runApplication*() {.async.} =
+proc startApplication*() {.async.} =
   proc aaa() {.async.} =
     while true:
       notice "a"

codexcrawler/metrics.nim

@@ -0,0 +1,14 @@
+import pkg/chronicles
+import pkg/metrics
+import pkg/metrics/chronos_httpserver
+
+proc setupMetrics*(metricsAddress: IpAddress, metricsPort: Port) =
+  let metricsAddress = metricsAddress
+  notice "Starting metrics HTTP server",
+    url = "http://" & $metricsAddress & ":" & $metricsPort & "/metrics"
+  try:
+    startMetricsHttpServer($metricsAddress, metricsPort)
+  except CatchableError as exc:
+    raiseAssert exc.msg
+  except Exception as exc:
+    raiseAssert exc.msg # TODO fix metrics

codexcrawler/utils.nim

@@ -0,0 +1,46 @@
+import std/parseutils
+import pkg/chronos
+
+when not declared(parseDuration): # Odd code formatting to minimize diff v. mainLine
+  const Whitespace = {' ', '\t', '\v', '\r', '\l', '\f'}
+
+  func toLowerAscii(c: char): char =
+    if c in {'A' .. 'Z'}:
+      char(uint8(c) xor 0b0010_0000'u8)
+    else:
+      c
+
+  func parseDuration*(s: string, size: var Duration): int =
+    ## Parse a size qualified by simple time into `Duration`.
+    ##
+    runnableExamples:
+      var res: Duration # caller must still know if 'b' refers to bytes|bits
+      doAssert parseDuration("10H", res) == 3
+      doAssert res == initDuration(hours = 10)
+      doAssert parseDuration("64m", res) == 6
+      doAssert res == initDuration(minutes = 64)
+      doAssert parseDuration("7m/block", res) == 2 # '/' stops parse
+      doAssert res == initDuration(minutes = 7) # 1 shl 30, forced binary metric
+      doAssert parseDuration("3d", res) == 2 # '/' stops parse
+      doAssert res == initDuration(days = 3) # 1 shl 30, forced binary metric
+
+    const prefix = "s" & "mhdw" # byte|bit & lowCase metric-ish prefixes
+    const timeScale = [1.0, 60.0, 3600.0, 86_400.0, 604_800.0]
+
+    var number: float
+    var scale = 1.0
+    result = parseFloat(s, number)
+    if number < 0: # While parseFloat accepts negatives ..
+      result = 0 #.. we do not since sizes cannot be < 0
+    else:
+      let start = result # Save spot to maybe unwind white to EOS
+      while result < s.len and s[result] in Whitespace:
+        inc result
+      if result < s.len: # Illegal starting char => unity
+        if (let si = prefix.find(s[result].toLowerAscii); si >= 0):
+          inc result # Now parse the scale
+          scale = timeScale[si]
+      else: # Unwind result advancement when there..
+        result = start #..is no unit to the end of `s`.
+      var sizeF = number * scale + 0.5 # Saturate to int64.high when too big
+      size = seconds(int(sizeF))

codexcrawler/version.nim

@@ -0,0 +1,24 @@
+import std/strutils
+
+proc getCrawlerVersion(): string =
+  let tag = strip(staticExec("git tag"))
+  if tag.isEmptyOrWhitespace:
+    return "untagged build"
+  return tag
+
+proc getCrawlerRevision(): string =
+  # using a slice in a static context breaks nimsuggest for some reason
+  var res = strip(staticExec("git rev-parse --short HEAD"))
+  return res
+
+proc getNimBanner(): string =
+  staticExec("nim --version | grep Version")
+
+const
+  crawlerVersion* = getCrawlerVersion()
+  crawlerRevision* = getCrawlerRevision()
+  nimBanner* = getNimBanner()
+
+  crawlerFullVersion* =
+    "CodexNetworkCrawler version:  " & crawlerVersion & "\p" & "CodexNetworkCrawler revision: " & crawlerRevision & "\p" &
+    nimBanner