all: move the documentation under _www/doc directory

This also allow the latest/released documentation viewed on
the web user interface under /doc path.

While at it, reformat HTML and CSS files using js-beautify and
JavaScript files using clang-format [1].

[1] https://google.github.io/styleguide/jsguide.html#formatting

12 files changed, 919 insertions, 0 deletions

diff --git a/_www/doc/CHANGELOG.adoc b/_www/doc/CHANGELOG.adoc
new file mode 120000
index 0000000..dbe8cbb
--- /dev/null
+++ b/_www/doc/CHANGELOG.adoc
@@ -0,0 +1 @@
+../../CHANGELOG.adoc
\ No newline at end of file
diff --git a/_www/doc/README.adoc b/_www/doc/README.adoc
new file mode 120000
index 0000000..35c2551
--- /dev/null
+++ b/_www/doc/README.adoc
@@ -0,0 +1 @@
+../../README.adoc
\ No newline at end of file
diff --git a/_www/doc/benchmark.adoc b/_www/doc/benchmark.adoc
new file mode 100644
index 0000000..baf856c
--- /dev/null
+++ b/_www/doc/benchmark.adoc
@@ -0,0 +1,125 @@
+// SPDX-FileCopyrightText: 2020 M. Shulhan <ms@kilabit.info>
+// SPDX-License-Identifier: GPL-3.0-or-later
+= Benchmark
+
+Commit: e670b34
+Build: normal
+
+Config options,
+
+----
+dir.hosts=/etc/rescached/hosts.d
+dir.master=/etc/rescached/master.d
+debug = 0
+----
+
+== resolverbench
+
+Result of benchmarking with local blocked host file,
+
+----
+master ms 0 % ./resolverbench 127.0.0.1:53 scripts/hosts.block
+= Benchmarking with 27367 messages
+= Total: 27367
+= Failed: 0
+= Elapsed time: 1.053238347s
+----
+
+== dnstrace
+
+Result of benchmarking with 10000 query and 100 concurrent connections,
+
+----
+master ms 0 % dnstrace --recurse --codes --io-errors -s 127.0.0.1:53 -t A -n 10000 -c 100 redsift.io
+Benchmarking 127.0.0.1:53 via udp with 100 conncurrent requests
+
+Total requests:  1000000 of 1000000 (100.0%)
+DNS success codes:      1000000
+
+DNS response codes
+        NOERROR:        1000000
+
+Time taken for tests:    10.318186376s
+Questions per second:    96916.3
+
+DNS timings, 1000000 datapoints
+         min:            0s
+         mean:           1.017194ms
+         [+/-sd]:        770.525µs
+         max:            39.845887ms
+
+DNS distribution, 1000000 datapoints
+    LATENCY   |                                             | COUNT
++-------------+---------------------------------------------+--------+
+  131.071µs   |                                             |   1722
+  393.215µs   | ▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄                            | 115890
+  655.359µs   | ▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄                   | 185089
+  917.503µs   | ▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄ | 316551
+  1.179647ms  | ▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄   | 300305
+  1.441791ms  | ▄▄▄▄                                        |  31218
+  1.703935ms  | ▄▄                                          |  12005
+  1.966079ms  | ▄                                           |   6387
+  2.228223ms  | ▄                                           |   5007
+  2.490367ms  |                                             |   3196
+  2.752511ms  |                                             |   2573
+  3.014655ms  |                                             |   2486
+  3.276799ms  |                                             |   2012
+  3.538943ms  |                                             |   1814
+  3.801087ms  |                                             |   1806
+  4.063231ms  |                                             |   1512
+  4.325375ms  |                                             |   1099
+  4.587519ms  |                                             |   1077
+  4.849663ms  |                                             |    785
+  5.111807ms  |                                             |    759
+  5.373951ms  |                                             |    901
+  5.636095ms  |                                             |    765
+  5.898239ms  |                                             |    874
+  6.160383ms  |                                             |    654
+  6.422527ms  |                                             |    476
+  6.684671ms  |                                             |    351
+  6.946815ms  |                                             |    294
+  7.208959ms  |                                             |    245
+  7.471103ms  |                                             |    292
+  7.733247ms  |                                             |    261
+  7.995391ms  |                                             |    255
+  8.257535ms  |                                             |    132
+  8.650751ms  |                                             |    396
+  9.175039ms  |                                             |    193
+  9.699327ms  |                                             |     78
+  10.223615ms |                                             |     51
+  10.747903ms |                                             |    102
+  11.272191ms |                                             |     23
+  11.796479ms |                                             |      0
+  12.320767ms |                                             |      0
+  12.845055ms |                                             |      0
+  13.369343ms |                                             |      0
+  13.893631ms |                                             |      0
+  14.417919ms |                                             |      0
+  14.942207ms |                                             |      0
+  15.466495ms |                                             |      0
+  15.990783ms |                                             |      0
+  16.515071ms |                                             |      0
+  17.301503ms |                                             |      0
+  18.350079ms |                                             |      0
+  19.398655ms |                                             |    192
+  20.447231ms |                                             |    112
+  21.495807ms |                                             |      0
+  22.544383ms |                                             |      0
+  23.592959ms |                                             |      0
+  24.641535ms |                                             |     12
+  25.690111ms |                                             |     28
+  26.738687ms |                                             |     14
+  27.787263ms |                                             |      5
+  28.835839ms |                                             |      0
+  29.884415ms |                                             |      0
+  30.932991ms |                                             |      0
+  31.981567ms |                                             |      0
+  33.030143ms |                                             |      0
+  34.603007ms |                                             |      0
+  36.700159ms |                                             |      0
+  38.797311ms |                                             |      1
+----
+
+== Credits
+
+- https://github.com/redsift/dnstrace[dnstrace]
diff --git a/_www/doc/html.tmpl b/_www/doc/html.tmpl
new file mode 100644
index 0000000..4eea130
--- /dev/null
+++ b/_www/doc/html.tmpl
@@ -0,0 +1,34 @@
+<!DOCTYPE html>
+<!-- SPDX-FileCopyrightText: 2022 M. Shulhan <ms@kilabit.info -->
+<!-- SPDX-License-Identifier: GPL-3.0-or-later -->
+<html lang="en">
+
+<head>
+    <meta charset="utf-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no" />
+    <link rel="icon" type="image/png" href="/favicon.png" />
+    <link rel="stylesheet" href="/index.css" />
+    <title>rescached | doc</title>
+</head>
+
+<body>
+    <nav class="menu">
+        <a href="/"> rescached </a>
+        /
+        <a href="/environment/"> Environment </a>
+        /
+        <a href="/block.d/"> block.d </a>
+        /
+        <a href="/hosts.d/"> hosts.d </a>
+        /
+        <a href="/zone.d/"> zone.d </a>
+        /
+        <a href="/doc/" class="active"> Documentation </a>
+    </nav>
+
+    <div class="page">
+        <div class="container">{{.Body}}</div>
+    </div>
+</body>
+
+</html>
diff --git a/_www/doc/images/Screenshot_wui_environment.png b/_www/doc/images/Screenshot_wui_environment.png
new file mode 100644
index 0000000..0e8c60d
--- /dev/null
+++ b/_www/doc/images/Screenshot_wui_environment.png
diff --git a/_www/doc/images/Screenshot_wui_frontpage.png b/_www/doc/images/Screenshot_wui_frontpage.png
new file mode 100644
index 0000000..0ee949b
--- /dev/null
+++ b/_www/doc/images/Screenshot_wui_frontpage.png
diff --git a/_www/doc/images/Screenshot_wui_hosts_blocks.png b/_www/doc/images/Screenshot_wui_hosts_blocks.png
new file mode 100644
index 0000000..7eaebe2
--- /dev/null
+++ b/_www/doc/images/Screenshot_wui_hosts_blocks.png
diff --git a/_www/doc/images/Screenshot_wui_hosts_d.png b/_www/doc/images/Screenshot_wui_hosts_d.png
new file mode 100644
index 0000000..b096fa0
--- /dev/null
+++ b/_www/doc/images/Screenshot_wui_hosts_d.png
diff --git a/_www/doc/images/Screenshot_wui_zone_d.png b/_www/doc/images/Screenshot_wui_zone_d.png
new file mode 100644
index 0000000..52e7913
--- /dev/null
+++ b/_www/doc/images/Screenshot_wui_zone_d.png
diff --git a/_www/doc/index.adoc b/_www/doc/index.adoc
new file mode 100644
index 0000000..3c9ff89
--- /dev/null
+++ b/_www/doc/index.adoc
@@ -0,0 +1,35 @@
+// SPDX-FileCopyrightText: 2022 M. Shulhan <ms@kilabit.info>
+// SPDX-License-Identifier: GPL-3.0-or-later
+= rescached documentation
+Shulhan <ms@kilabit.info>
+
+link:CHANGELOG.html[CHANGELOG]:: Log for each release.
+
+link:README.html[rescached]:: Manual page for rescached program.
+
+link:rescached.cfg.html[rescached.cfg]:: Manual page for rescached
+configuration.
+
+link:resolver.html[resolver]:: Manual page for resolver.
+
+link:benchmark.html[Benchmark]:: The latest benchmark of rescached server.
+
+
+[#todo]
+==  TODO
+
+* zone.d rr add - check for duplicate value.
+
+* Prioritize the order of hosts file to be loaded:
+** block.d
+** hosts.d
+** zone.d
+** /etc/hosts
+
+* Generate unique ID for each RR in caches/zone for deletion.
+
+* Move repository to sr.ht
+
+* Implement DNS type 65
+
+* Implement DNSSec
diff --git a/_www/doc/rescached.cfg.adoc b/_www/doc/rescached.cfg.adoc
new file mode 100644
index 0000000..2e19cac
--- /dev/null
+++ b/_www/doc/rescached.cfg.adoc
@@ -0,0 +1,263 @@
+// SPDX-FileCopyrightText: 2020 M. Shulhan <ms@kilabit.info>
+// SPDX-License-Identifier: GPL-3.0-or-later
+= RESCACHED.CONF(5)
+:doctype: manpage
+:man source: rescached.cfg
+:man version: 2020.05.10
+:man manual: rescached.cfg
+
+
+== NAME
+
+rescached.cfg - Configuration for rescached service
+
+
+== SYNOPSIS
+
+/etc/rescached/rescached.cfg
+
+
+== DESCRIPTION
+
+These file configure the behaviour of *rescached*(1) service.
+This section will explain more about each option and how they effect
+`rescached`.
+
+The configuration is using INI format where each options is grouped by header
+in square bracket:
+
+* `[rescached]`
+* `[dns "server"]`
+
+
+== OPTIONS
+
+=== [rescached]
+
+This group of options contain the main configuration that related to
+rescached.
+
+[#wui-listen]
+==== wui.listen
+
+Format:: [host]:port
+Default:: 127.0.0.1:5380
+Description:: The address to listen for web user interface.
+
+[#file-resolvconf]
+==== file.resolvconf
+
+Format:: /any/path/to/file
+Default:: /etc/rescached/resolv.conf
+Description:: A path to dynamically generated *resolv.conf*(5) by
+*resolvconf*(8).
++
+--
+If set, the nameserver values in referenced file will be used as "parent" name
+server if no "parent" is defined in configuration file.
+
+To use this config, you must set either "dnsmasq_resolv", "pdnsd_resolv", or
+"unbound_conf" in "/etc/resolvconf.conf" to point to
+"/etc/rescached/resolv.conf".
+
+For example,
+----
+resolv_conf=/etc/resolv.conf
+name_servers=127.0.0.1
+dnsmasq_resolv=/etc/rescached/resolv.conf
+#pdnsd_resolv=/etc/rescached/resolv.conf
+#unbound_conf=/etc/rescached/resolv.conf
+----
+--
+
+[#debug]
+==== debug
+
+Value::
+0::: log startup and errors.
+1::: log startup, errors, request, response, caches, and exit status.
+Format:: 	Number (0 or 1).
+Default:: 	0
+Description:: 	This option only used for debugging program or if user want to
+monitor what kind of traffic goes in and out of rescached.
+
+[#dns_server]
+=== [dns "server"]
+
+This group of options related to DNS server.
+
+[#parent]
+==== parent
+
+Format::
+
+----
+parent  = "parent = " [ scheme "://"] ( ip-address / domain-name ) [ ":" port ]
+scheme  = ( "udp" / "https")
+----
+
+Default::
+* Address: udp://1.1.1.1
+* Port: 53
+Description:: List of parent DNS servers.
++
+When `rescached` receive a query from client (for example, your browser) and
+when it does not have a cached answer for that query, it will forward the
+query to one of the parent name servers.
++
+Using UDP as parent scheme, will automatically assume that the server also
+capable of handling query in TCP.
+This is required when client (for example, your browser) re-send the query
+after receiving truncated UDP answer.
+Any query received by `rescached` through TCP will forwarded to the parent
+name server as TCP too, using the same address and port defined in one of UDP
+parent.
++
+Please, do not use OpenDNS server.
+If certain host-name not found (i.e. typo in host-name), OpenDNS will reply
+with its own address, instead of replying with empty answer.
+This will make `rescached` caching a false data and it may make your
+application open or consume unintended resources.
++
+To check if your parent server reply the unknown host-name with no answer, use
+*resolver*(1) tool.
+
+Example::
+----
+## Using UDP connection to forward request to parent name server.
+parent = udp://1.1.1.1
+
+## Using DNS over TLS to forward request to parent name server.
+parent = https://1.1.1.1
+
+## Using DNS over HTTPS to forward request to parent name server.
+parent = https://kilabit.info/dns-query
+----
+
+[#listen]
+==== listen
+
+Format:: 	<IP-ADDRESS>:<PORT>
+Default:: 	127.0.0.1:53
+Description:: 	Address in local network where `rescached` will listening for
+query from client.
++
+If you want rescached to serve a query from another host in your local
+network, change this value to `0.0.0.0:53`.
+
+[#http-port]
+==== http.port
+
+Format:: Number
+Default:: 443
+Description:: Port to serve DNS over HTTP.
+
+[#tls-port]
+==== tls.port
+
+Format:: Number
+Default:: 853
+Description:: Port to serve DNS over TLS.
+
+[#tls-certificate]
+==== tls.certificate
+
+Format:: /path/to/file
+Default:: (empty)
+Description:: Path to certificate file to serve DNS over TLS and HTTPS.
+
+
+[#tls-private_key]
+==== tls.private_key
+
+Format:: /path/to/file
+Default:: (empty)
+Description:: Path to certificate private key file to serve DNS over TLS and
+HTTPS.
+
+[#tls-allow_insecure]
+==== tls.allow_insecure
+
+Format:: true | false
+Default:: false
+Description:: If its true, allow serving DoH and DoT with self-signed
+certificate.
+
+[#doh-behind_proxy]
+==== doh.behind_proxy
+
+Format:: true | false
+Default:: false
+Description:: If its true, serve DNS over HTTP only, even if
+certificate files is defined.
+This allow serving DNS request forwarded by another proxy server.
+
+[#cache-prune_delay]
+==== cache.prune_delay
+
+Format:: 	Duration with time unit. Valid time units are "s", "m", "h".
+Default:: 	1h
+Description::   Delay for pruning caches.
++
+Every N seconds/minutes/hours, rescached will traverse all
+caches and remove response that has not been accessed less than
+`cache.prune_threshold`.
+Its value must be equal or greater than 1 hour (3600 seconds).
+
+[#cache-prune_threshold]
+==== cache.prune_threshold
+
+Format:: 	Duration with time unit. Valid time units are "s", "m", "h".
+Default:: 	-1h
+Description:: 	The duration when the cache will be considered expired.
+Its value must be negative and greater or equal than -1 hour (-3600 seconds).
+
+== FILES
+
+[#hosts-d]
+=== /etc/rescached/hosts.d
+
+Path to hosts directory where rescached will load all hosts formatted files.
+
+
+[#zone-d]
+=== /etc/rescached/zone.d
+
+Path to zone directory where rescached will load all zone files.
+
+
+== EXAMPLE
+
+Simple rescached configuration using dnscrypt-proxy that listen on port 54 as
+parent resolver, with prune delay set to 60 seconds and threshold also to 60
+seconds.
+
+----
+[dns "server"]
+parent=udp://127.0.0.1:54
+cache.prune_delay=60s
+cache.prune_threshold=60s
+----
+
+Save the above script into `rescached.cfg` and run it,
+
+	$ sudo rescached -config rescached.cfg
+
+
+== AUTHOR
+
+`rescached` is developed by M. Shulhan (m.shulhan@gmail.com).
+
+
+== LICENSE
+
+Copyright 2018, M. Shulhan (m.shulhan@gmail.com).
+All rights reserved.
+
+Use of this source code is governed by a GPL-3.0 license that can be
+found in the COPYING file.
+
+
+== SEE ALSO
+
+*rescached*(1)
diff --git a/_www/doc/resolver.adoc b/_www/doc/resolver.adoc
new file mode 100644
index 0000000..de34a25
--- /dev/null
+++ b/_www/doc/resolver.adoc
@@ -0,0 +1,460 @@
+// SPDX-FileCopyrightText: 2020 M. Shulhan <ms@kilabit.info>
+// SPDX-License-Identifier: GPL-3.0-or-later
+= RESOLVER(1)
+:doctype: manpage
+:man source: resolver
+:man version: 2022.04.15
+:man manual: resolver
+
+
+== NAME
+
+resolver - command line interface for DNS and rescached server.
+
+
+== SYNOPSIS
+
+resolver [-insecure] [-ns nameserver] [-server] <command> [args...]
+
+
+== DESCRIPTION
+
+resolver is a tool to resolve hostname to IP address or to query services
+on hostname by type (MX, SOA, TXT, etc.) using standard DNS protocol with UDP,
+DNS over TLS (DoT), or DNS over HTTPS (DoH).
+
+
+== OPTIONS
+
+The following options affect the commands operation.
+
+`-insecure`::
++
+--
+Ignore invalid server certificate when querying DoT, DoH, or rescached server.
+--
+
+`-ns <nameserver>`::
++
+--
+This option define the parent DNS server where the resolver send the query.
+Default to one of "nameserver" in `/etc/resolv.conf`.
+
+The nameserver is defined in the following format,
+
+		("udp"/"tcp"/"https") "://" (domain / ip-address) [":" port]
+
+Examples,
+
+* udp://194.233.68.184:53 for querying with UDP,
+* tcp://194.233.68.184:53 for querying with TCP,
+* https://194.233.68.184:853 for querying with DNS over TLS (DoT), and
+* https://kilabit.info/dns-query for querying with DNS over HTTPS (DoH).
+--
+
+`-server <rescached-URL>`::
++
+--
+Set the rescached HTTP server where commands will send.
+The rescached-URL use HTTP scheme:
+
+	("http" / "https") "://" (domain / ip-address) [":" port]
+
+Default to "https://127.0.0.1:5380" if its empty.
+--
+
+==  COMMANDS
+
+===  QUERY
+
+query <domain / ip-address> [type] [class]::
++
+--
+Query the domain or IP address with optional type and/or class.
+
+Unless the option "-ns" is given, the query command will use the
+nameserver defined in the system resolv.conf file.
+
+The "type" parameter define DNS record type to be queried.
+List of valid types,
+
+* A       (1) - a host Address (default)
+* NS      (2) - an authoritative Name Server
+* CNAME   (5) - the Canonical NAME for an alias
+* SOA     (6) - marks the Start of a zone of Authority
+* MB      (7) - a MailBox domain name
+* MG      (8) - a Mail Group member
+* MR      (9) - a Mail Rename domain name
+* NULL   (10) - a null resource record
+* WKS    (11) - a Well Known Service description
+* PTR    (12) - a domain name PoinTeR
+* HINFO  (13) - Host INFOrmation
+* MINFO  (14) - mailbox or mail list information
+* MX     (15) - Mail Exchange
+* TXT    (16) - TeXT strings
+* AAAA   (28) - a host address in IPv6
+* SRV    (33) -  a SerViCe record
+
+The "class" parameter is optional, its either IN (default), CS, or HS.
+--
+
+
+===  MANAGING BLOCK.D
+
+block.d disable <name>::
++
+--
+Disable specific hosts on block.d.
+--
+
+block.d enable <name>::
++
+--
+Enable specific hosts on block.d.
+--
+
+block.d update <name>::
++
+--
+Fetch the latest hosts file from remote block.d URL defined by
+its name.
+On success, the hosts file will be updated and the server will be
+restarted.
+--
+
+
+===  MANAGING CACHES
+
+caches::
++
+--
+Fetch and print all caches from rescached server.
+--
+
+
+caches search <string>::
++
+--
+Search the domain name in rescached caches.
+This command can also be used to inspect each DNS message on the caches.
+--
+
+caches remove <string>::
++
+--
+Remove the domain name from rescached caches.
+If the parameter is "all", it will remove all caches.
+--
+
+
+===  MANAGING ENVIRONMENT
+
+env::
++
+--
+Fetch the current server environment and print it as JSON format to stdout.
+--
+
+env update <path-to-file / "-">::
++
+--
+Update the server environment from JSON formatted file.
+If the argument is "-", the new environment is read from stdin.
+If the environment is valid, the server will be restarted.
+--
+
+
+===  MANAGING HOSTS.D
+
+hosts.d create <name>::
++
+--
+Create new hosts file inside the hosts.d directory with specific file
+name.
+--
+
+hosts.d delete <name>::
++
+--
+Delete hosts file inside the hosts.d directory by file name.
+--
+
+hosts.d get <name>::
++
+--
+Get the content of hosts file inside the hosts.d directory by file name.
+--
+
+
+===  MANAGING RECORD IN HOSTS.D
+
+hosts.d rr add <name> <domain> <value>::
++
+--
+Insert a new record and save it to the hosts file identified by
+"name".
+If the domain name already exists, the new record will be appended
+instead of replaced.
+--
+
+hosts.d rr delete <name> <domain>::
++
+--
+Delete record from hosts file "name" by domain name.
+--
+
+
+===  MANAGING ZONE.D
+
+`zone.d`::
++
+Fetch and print all zones in the server, including their SOA.
+
+zone.d create <name>::
++
+Create new zone file inside the zone.d directory.
+
+zone.d delete <name>::
++
+Delete zone file inside the zone.d directory.
+
+
+===  MANAGING RECORD IN ZONE.D
+
+`zone.d rr get <zone>`::
+
+Get and print all records in the zone.
+
+zone.d rr add <zone> <"@" | subdomain> <ttl> <type> <class> <value> ...::
++
+--
+Add new record into the zone file.
+
+The domain name can be set to origin using "@" or empty string, subdomain
+(without ending with "."), or fully qualified domain name (end with ".").
+
+If ttl is set to 0, it will default to 604800 (7 days).
+
+List of valid type are A, NS, CNAME, PTR, MX, TXT, and AAAA.
+
+List of valid class are IN, CS, HS.
+
+The value parameter can be more than one, for example, the MX record
+we pass two parameters:
+
+	<pref> <exchange>
+
+See the example below for more information.
+--
+
+`zone.d rr delete <zone> <"@" | subdomain> <type> <class> <value>`::
++
+--
+Delete record from zone by its subdomain, type, class, and value.
+--
+
+
+== EXIT STATUS
+
+Upon exit and success +resolver+ will return 0, or 1 otherwise.
+
+
+== EXAMPLES
+
+===  QUERY
+
+Query the IPv4 address for kilabit.info,
+
+	$ resolver query kilabit.info
+
+Query the mail exchange (MX) for domain kilabit.info,
+
+	$ resolver query kilabit.info MX
+
+Query the IPv4 address for kilabit.info using 127.0.0.1 at port 53 as
+name server,
+
+	$ resolver -ns=udp://127.0.0.1:53 query kilabit.info
+
+Query the IPv4 address of domain name "kilabit.info" using DNS over TLS at
+name server 194.233.68.184,
+
+	$ resolver -insecure -ns=https://194.233.68.184 query kilabit.info
+
+Query the IPv4 records of domain name "kilabit.info" using DNS over HTTPS on
+name server kilabit.info,
+
+	$ resolver -ns=https://kilabit.info/dns-query query kilabit.info
+
+Inspect the rescached's caches on server at http://127.0.0.1:5380,
+
+	$ resolver -server=http://127.0.0.1:5380 caches
+
+
+===  MANAGING CACHES
+
+Search caches that contains "bit" on the domain name,
+
+	$ resolver caches search bit
+
+Remove caches that contains domain name "kilabit.info",
+
+	$ resolver caches remove kilabit.info
+
+Remove all caches in the server,
+
+	$ resolver caches remove all
+
+
+===  MANAGING ENVIRONMENT
+
+Fetch and print current server environment,
+
+	$ resolver env
+
+Update the server environment from JSON file in /tmp/env.json,
+
+	$ resolver env update /tmp/env.json
+
+Update the server environment by reading JSON from standard input,
+
+	$ cat /tmp/env.json | resolver env update -
+
+
+===  MANAGING HOSTS.D
+
+Create new hosts file named "myhosts" inside the hosts.d directory,
+
+	$ resolver hosts.d create myhosts
+	OK
+
+Delete hosts file named "myhosts" inside the hosts.d directory,
+
+	$ resolver hosts.d delete myhosts
+	OK
+
+Get the content of hosts file named "myhosts" inside the hosts.d directory,
+
+	$ resolver hosts.d get myhosts
+	[
+	  {
+	    "Value": "127.0.0.1",
+	    "Name": "localhost",
+	    "Type": 1,
+	    "Class": 1,
+	    "TTL": 604800
+	  },
+	  {
+	    "Value": "::1",
+	    "Name": "localhost",
+	    "Type": 28,
+	    "Class": 1,
+	    "TTL": 604800
+	  }
+	]
+
+===  MANAGING RECORD IN HOSTS.D
+
+Add new record "127.0.0.1 my.hosts" to hosts file named "hosts",
+
+	$ resolver hosts.d rr add hosts my.hosts 127.0.0.1
+	{
+	  "Value": "127.0.0.1",
+	  "Name": "my.hosts",
+	  "Type": 1,
+	  "Class": 1,
+	  "TTL": 604800
+	}
+
+Delete record "my.hosts" from hosts file "hosts",
+
+	$ resolver hosts.d rr delete hosts my.hosts
+	{
+	  "Value": "127.0.0.1",
+	  "Name": "my.hosts",
+	  "Type": 1,
+	  "Class": 1,
+	  "TTL": 604800
+	}
+
+===  MANAGING ZONE.D
+
+Print all zone in the server,
+
+	$ resolver zone.d
+	my.zone
+	  SOA: {MName:my.zone RName: Serial:0 Refresh:0 Retry:0 Expire:0 Minimum:0}
+
+
+===  MANAGING RECORD IN ZONE.D
+
+Assume that we have create zone "my.zone".
+
+Get all records in the zone "my.zone",
+
+	$ resolver zone.d rr get my.zone
+	my.zone
+	  604800 MX IN map[Exchange:mail.my.zone Preference:10]
+	  604800  A IN 127.0.0.2
+	  604800  A IN 127.0.0.3
+	www.my.zone
+	  604800  A IN 192.168.1.2
+
+Add IPv4 address "127.0.0.1" for domain my.zone,
+
+	$ resolver zone.d rr add my.zone @ 0 A IN 127.0.0.1
+
+or
+
+	$ resolver zone.d rr add my.zone "" 0 A IN 127.0.0.1
+	{
+	  "Value": "127.0.0.1",
+	  "Name": "my.zone",
+	  "Type": 1,
+	  "Class": 1,
+	  "TTL": 604800
+	}
+
+and to delete the above record,
+
+	$ resolver zone.d rr delete my.zone @ A IN 127.0.0.1
+	OK
+
+Add subdomain "www" with IPv4 address "192.168.1.2" to zone "my.zone",
+
+	$ resolver zone.d rr add my.zone www 0 A IN 192.168.1.2
+	{
+	  "Value": "192.168.1.2",
+	  "Name": "www.my.zone",
+	  "Type": 1,
+	  "Class": 1,
+	  "TTL": 604800
+	}
+
+and to delete the above record,
+
+	$ resolver zone.d rr delete my.zone www A IN 192.168.1.2
+	OK
+
+== AUTHOR
+
+This software is developed by M. Shulhan (ms@kilabit.info).
+
+
+== LICENSE
+
+Copyright 2018, M. Shulhan (ms@kilabit.info).
+All rights reserved.
+
+Use of this source code is governed by a GPL 3.0 license that can be
+found in the COPYING file.
+
+
+== LINKS
+
+Source code repository: https://github.com/shuLhan/rescached-go
+
+
+== SEE ALSO
+
+*rescached*(1), *rescached.cfg*(5)