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NAME |
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EV::ADNS - lightweight asynchronous dns queries using EV and libadns |
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|
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SYNOPSIS |
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use EV; |
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use EV::ADNS; |
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|
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EV::ADNS::submit "example.com", EV::ADNS::r_addr, EV::ADNS::qf_cname_loose, sub { |
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my ($status, $expires, @a) = @_; |
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warn $a[0]; # "127.13.166.3" etc. |
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}; |
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|
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EV::run; |
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|
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DESCRIPTION |
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This is a simple interface to libadns (asynchronous dns) that integrates |
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well and automatically into the EV event loop. The documentation for |
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libadns is vital to understand this module, see |
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<http://www.chiark.greenend.org.uk/~ian/adns/>. |
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|
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You can use it only with EV (directly or indirectly, e.g. via Glib::EV). |
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Apart from loading and using the "submit" function you need not do |
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anything (except run an EV event loop). |
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|
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OVERVIEW |
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All the constants/enums from adns.h are available in the EV::ADNS |
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namespace, without the "adns_" prefix, i.e. "adns_r_a" becomes |
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"EV::ADNS::r_a" and so on. |
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|
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FUNCTIONS |
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$query = EV::ADNS::submit "domain", $rrtype, $flags, $cb |
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Submits a new request to be handled. See the "adns_submit" C |
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function description for more details. The function optionally |
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returns a query object which can be used to cancel an in-progress |
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request. You do not need to store the query object, even if you |
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ignore it, the query will proceed. |
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|
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The callback will be invoked with a result status, the time the |
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resource record validity expires and zero or more resource records, |
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one scalar per result record. Example: |
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|
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sub adns_cb { |
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my ($status, $expires, @rr) = @_; |
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if ($status == EV::ADNS::s_ok) { |
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use JSON::XS; |
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warn encode_json \@rr; |
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} |
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} |
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|
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The format of result records varies considerably, here is some |
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cursory documentation of how each record will look like, depending |
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on the query type: |
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|
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EV::ADNS::r_a, EV::ADNS::r_addr |
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An IPv4 address in dotted quad (string) form. |
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|
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EV::ADNS::r_ns_raw, EV::ADNS::r_cname, EV::ADNS::r_ptr, |
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EV::ADNS::r_ptr_raw |
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The resource record as a simple string. |
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|
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EV::ADNS::r_txt |
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An arrayref of strings. |
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|
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EV::ADNS::r_ns |
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A "host address", a hostname with any number of addresses (hint |
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records). |
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|
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The record will be an arrayref with domainname, adns status and |
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any number of associated addresses: "["domain", adns_status, |
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addr...]". |
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|
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EV::ADNS::r_hinfo |
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An arrayref consisting of the two strings. |
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|
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EV::ADNS::r_rp, EV::ADNS::r_rp_raw |
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An arrayref with two strings. |
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|
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EV::ADNS::r_mx |
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An arrayref consisting of the priority and a "host address" (see |
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"EV::ADNS::r_ns"). Example: |
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|
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[10, [["alt3.aspmx.l.google.com", 0, "64.233.189.27", "2404:6800:4008:c07::1a"]]] |
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|
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EV::ADNS::r_mx_raw |
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An arrayref consisting of the priority and the hostname, e.g. |
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"[10, "mail.example.com"]". |
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|
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EV::ADNS::r_soa, EV::ADNS::r_soa_raw |
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An arrayref consisting of the primary nameserver, admin name, |
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serial, refresh, retry expire and minimum times, e.g.: |
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|
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["ns.example.net", "hostmaster@example.net", 2000001102, 86400, 21600, 2592000, 172800] |
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|
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The "raw" form doesn't mangle the e-mail address. |
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|
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EV::ADNS::r_srv_raw |
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An arrayref consisting of the priority, weight, port and |
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hostname, e.g.: |
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|
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[10, 10, 5060, "sip1.example.net"] |
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|
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EV::ADNS::r_srv |
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The same as "EV::ADNS::r_srv_raw", but the hostname is replaced |
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by a "host address" (see "EV::ADNS::r_ns"). |
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|
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EV::ADNS::r_unknown |
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A single octet string with the raw contents. |
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|
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anything else |
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Currently "undef". |
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|
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$query->cancel |
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Cancels a request that is in progress. |
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|
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EV::ADNS::reinit undef, $resolvdata_or_undef |
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Cancels all outstanding queries, frees all adns state and |
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reinitialises it. It is highly recommended to only call this when |
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there are no outstanding requests. |
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|
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The first argument must currently be specified as "undef". |
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|
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The second argument can be missing or "undef"; in which case the |
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normal initialisation is done (such as reading the resolv.conf), or |
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it might be a stirng, in which case no config files or environment |
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variables will be read and the given string will be interpreted as |
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the resolv.conf contents. |
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|
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SEE ALSO |
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EV, Net::ADNS another interface to adns, maybe better, but without real |
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support to integrate it into other event loops. |
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|
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AUTHOR |
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Marc Lehmann <schmorp@schmorp.de> |
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http://home.schmorp.de/ |
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