Dockerfile with one-shot mode

Intended usage: Quick resolution attempt with an empty cache.

export QNAME=...
export QTYPE=...
sudo -E docker run -e QNAME -e QTYPE krestest:latest '-n' '-c' '/etc/knot-resolver/kresd.conf'

diff --git a/etc/config/config.docker b/etc/config/config.docker
index eaaffc9b049a058375953ffae871264f548f79e5..b7739e4954e1bee59b8cfdc1448e3027091e1e8a 100644 (file)
--- a/etc/config/config.docker
+++ b/etc/config/config.docker
@@ -1,37 +1,84 @@
 -- SPDX-License-Identifier: CC0-1.0
 -- vim:syntax=lua:set ts=4 sw=4:
 -- Refer to manual: https://knot-resolver.readthedocs.io/en/stable/
+print('Knot Resolver ' .. package_version())
 
--- Listen on all interfaces (localhost would not work in Docker)
-net.listen('0.0.0.0', 53, { kind = 'dns' })
-net.listen('0.0.0.0', 853, { kind = 'tls' })
-net.listen('0.0.0.0', 443, { kind = 'doh' })
-net.listen('0.0.0.0', 8453, { kind = 'webmgmt' })
-
--- Load Useful modules
-modules = {
-       'stats',    -- Track internal statistics
-       'http',
-}
-
--- Smaller cache size
-cache.size = 10 * MB
-
-function print_help()
-       print('\nUsage\n'
-          .. '=====\n'
-          .. 'Run this container using command:\n'
-          .. '$ docker run -Pti cznic/knot-resolver\n'
-          .. '\n'
-          .. 'Docker will map ports 53, 443, 853, and 8453 to some other numbers, see\n'
-          .. '$ docker ps\n'
-          .. '(column PORTS)\n'
-          .. '53   -> DNS protocol over UDP and TCP\n'
-          .. '443  -> DNS-over-HTTPS protocol\n'
-          .. '853  -> DNS-over-TLS protocol\n'
-          .. '8453 -> web interface\n'
-          .. '\n'
-          .. 'For verbose logging enter following command to prompt below:\n'
-          .. 'verbose(true)\n')
+function interactive_mode()
+       -- Listen on all interfaces (localhost would not work in Docker)
+       net.listen('0.0.0.0', 53, { kind = 'dns' })
+       net.listen('0.0.0.0', 853, { kind = 'tls' })
+       net.listen('0.0.0.0', 443, { kind = 'doh' })
+       net.listen('0.0.0.0', 8453, { kind = 'webmgmt' })
+
+       -- Load Useful modules
+       modules = {
+               'stats',    -- Track internal statistics
+               'http',
+       }
+
+       -- Smaller cache size
+       cache.size = 10 * MB
+
+       function print_help()
+               print('\nUsage\n'
+                  .. '=====\n'
+                  .. 'Run this container using command:\n'
+                  .. '$ docker run -Pti cznic/knot-resolver\n'
+                  .. '\n'
+                  .. 'Docker will map ports 53, 443, 853, and 8453 to some other numbers, see\n'
+                  .. '$ docker ps\n'
+                  .. '(column PORTS)\n'
+                  .. '53   -> DNS protocol over UDP and TCP\n'
+                  .. '443  -> DNS-over-HTTPS protocol\n'
+                  .. '853  -> DNS-over-TLS protocol\n'
+                  .. '8453 -> web interface\n'
+                  .. '\n'
+                  .. 'For verbose logging enter following command to prompt below:\n'
+                  .. 'verbose(true)\n')
+       end
+       print_help()
+end
+
+function debug_mode(qname, qtype)
+       env.KRESD_NO_LISTEN = 1
+
+       -- limit noise in verbose logs
+       modules.unload('detect_time_skew')
+       modules.unload('priming')
+       modules.unload('ta_signal_query')
+       modules.unload('ta_update')
+
+
+       -- execute query right after start up and exit when the query is finished
+       event.after(0, function()
+               -- ultra verbose log
+               verbose(true)
+               policy.add(policy.all(policy.DEBUG_ALWAYS))
+               log('INFO: starting your DNS query for %s %s, verbose log follows', qname, kres.tostring.type[qtype])
+               resolve({
+                       name = qname,
+                       type = qtype,
+                       finish = function(pkt)
+                               -- delay exit after packet is finished
+                               -- to prevent us from losing policy.DEBUG finish callback
+                               event.after(1,
+                                       function()
+                                               os.exit()
+                                       end)
+                               end
+               })
+       end)
+end
+
+local qname = os.getenv('QNAME')
+local qtype = os.getenv('QTYPE')
+if qname and qtype then
+       qtypenum = kres.type[qtype]
+       if not qtypenum then
+               log('ERROR: unsupported query type "%s", use TYPE12345 notation', qtype)
+               os.exit()
+       end
+       debug_mode(qname, qtypenum)
+else
+       interactive_mode()
 end
-print_help()