add RSSMIX_DEBUG env var

this can help figuring out which feed is broken when fetching for example

src/rss.nim

@@ -1,5 +1,6 @@
-import std/[algorithm, json, xmltree, times, options, sequtils]
+import std/[algorithm, json, xmltree, times, options, sequtils, strformat]
 import pkg/[mummy, rssatom, puppy, pretty]
+import ./[shared]
 
 const
   atomTimeFormat* {.strdefine.} = "yyyy-MM-dd'T'HH:mm:ss'Z'"
@@ -32,7 +33,9 @@ proc getTime(r: RssItem): DateTime =
 proc cmpRssItem(x, y: RssItem): int =
   cmp(x.getTime(), y.getTime())
 
-proc mixRssFeeds*(feeds: seq[RssFeed], name, id, link, authorName, description:string): RSS =
+proc mixRssFeeds*(
+    feeds: seq[RssFeed], name, id, link, authorName, description: string
+): RSS =
   result = RSS()
   result.id = name.some()
   result.title = id.some()
@@ -41,18 +44,22 @@ proc mixRssFeeds*(feeds: seq[RssFeed], name, id, link, authorName, description:s
   result.description = description.some()
   var entries: seq[RSS]
   for feed in feeds:
+    relDebug:
+      echo &"[feed {name}] fetching {feed.url}"
+    let fetched = fetch(feed.url)
     case feed.kind
     of Atom:
-      entries.add parseAtom(fetch(feed.url))
+      entries.add parseAtom(fetched)
     of RSSv2:
-      entries.add parseRss(fetch(feed.url))
+      entries.add parseRss(fetched)
 
       entries[^1].items = entries[^1].items.mapIt(
         block:
           var item = it
           if feed.timeFormat.len != 0 and item.pubDate.isSome():
             # if the IDE screams at you here, ignore it
-            item.pubdate = some(parse(item.pubDate.get(), feed.timeFormat).format(atomTimeFormat))
+            item.pubdate =
+              some(parse(item.pubDate.get(), feed.timeFormat).format(atomTimeFormat))
           else:
             item.pubdate = some(getRssv2Time(item).format(atomTimeFormat))
           item

src/rssmix.nim

@@ -33,7 +33,8 @@ proc atomHandler(r: Request) {.gcsafe, thread.} =
     headers["Content-Type"] = "application/atom+xml"
 
     var cfg = configs[name]
-  let mixed = mixRssFeeds(cfg, "rssmix: "&name, name, "/atom/"&name, "rssmix", "mix of various rss feeds")
+  let mixed =
+    mixRssFeeds(cfg, name, name, "/atom/" & name, "rssmix", "mix of various rss feeds")
 
   r.respond(200, headers, body = $assembleAtom(mixed))
 
@@ -46,10 +47,10 @@ proc stop() =
   quit()
 
 proc addfeeds(name: string, feeds: seq[RssFeed]) =
-  if configs.contains(name): raise newException(KeyError, "duplicate config: "&name)
+  if configs.contains(name):
+    raise newException(KeyError, "duplicate config: " & name)
   configs[name] = feeds
 
-
 proc main() =
   block:
     var cfgs = commandLineParams()
@@ -66,13 +67,12 @@ proc main() =
         for f in walkFiles(cfg / "*"):
           let cfg = readFile(f).parseConfig()
           addfeeds(cfg.name, cfg.feeds)
-    if configs.len == 0: quit("no configs found.", QuitFailure)
+    if configs.len == 0:
+      quit("no configs found.", QuitFailure)
     echo "registered feeds:"
     for key, value in configs.pairs:
       echo " - ", key, " (", value.len, " sub-feeds)"
 
-
-
   var router: Router
   router.get("/atom/@name", atomHandler)
 

src/shared.nim

@@ -0,0 +1,6 @@
+import std/[os]
+export existsEnv
+
+template relDebug*(body) =
+  if existsEnv("RSSMIX_DEBUG"):
+    body