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=head1 NAME |
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|
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EV::ADNS - lightweight asynchronous dns queries using EV and libadns |
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|
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=head1 SYNOPSIS |
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|
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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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=head1 DESCRIPTION |
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|
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This is a simple interface to libadns (asynchronous dns) that |
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integrates well and automatically into the EV event loop. The |
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documentation for libadns is vital to understand this module, see |
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L<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 |
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L<Glib::EV>). Apart from loading and using the C<submit> function you need |
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not do anything (except run an EV event loop). |
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|
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=head1 OVERVIEW |
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|
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All the constants/enums from F<adns.h> are available in the EV::ADNS |
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namespace, without the C<adns_> prefix, i.e. C<adns_r_a> becomes |
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C<EV::ADNS::r_a> and so on. |
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|
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=head1 FUNCTIONS |
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|
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=over 4 |
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|
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=item $query = EV::ADNS::submit "domain", $rrtype, $flags, $cb |
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|
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Submits a new request to be handled. See the C<adns_submit> C function |
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description for more details. The function optionally returns a query |
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object which can be used to cancel an in-progress request. You do not need |
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to store the query object, even if you ignore it, the query will proceed. |
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|
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The callback will be invoked with a result status, the time the resource |
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record validity expires and zero or more resource records, one scalar per |
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result record. Example: |
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|
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sub adns_cb { |
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my ($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 cursory |
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documentation of how each record will look like, depending on the query |
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type: |
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|
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=over 4 |
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|
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=item 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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=item EV::ADNS::r_ns_raw, EV::ADNS::r_cname, EV::ADNS::r_ptr, EV::ADNS::r_ptr_raw |
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|
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The resource record as a simple string. |
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|
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=item EV::ADNS::r_txt |
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|
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An arrayref of strings. |
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|
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=item EV::ADNS::r_ns |
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A "host address", a hostname with any number of addresses (hint records). |
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|
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The record will be an arrayref with domainname, adns status and any number |
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of associated addresses: C<< ["domain", adns_status, addr...] >>. |
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|
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=item EV::ADNS::r_hinfo |
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|
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An arrayref consisting of the two strings. |
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|
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=item 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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=item EV::ADNS::r_mx |
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|
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An arrayref consisting of the priority and a "host address" (see |
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C<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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=item EV::ADNS::r_mx_raw |
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|
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An arrayref consisting of the priority and the hostname, e.g. C<[10, |
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"mail.example.com"]>. |
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|
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=item EV::ADNS::r_soa, EV::ADNS::r_soa_raw |
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|
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An arrayref consisting of the primary nameserver, admin name, serial, |
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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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=item EV::ADNS::r_srv_raw |
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|
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An arrayref consisting of the priority, weight, port and hostname, e.g.: |
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[10, 10, 5060, "sip1.example.net"] |
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|
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=item EV::ADNS::r_srv |
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|
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The same as C<EV::ADNS::r_srv_raw>, but the hostname is replaced by a "host |
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address" (see C<EV::ADNS::r_ns>). |
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|
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=item EV::ADNS::r_unknown |
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|
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A single octet string with the raw contents. |
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=item anything else |
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Currently C<undef>. |
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|
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=back |
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|
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=item $query->cancel |
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Cancels a request that is in progress. |
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|
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=item EV::ADNS::reinit undef, $resolvdata_or_undef |
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|
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Cancels all outstanding queries, frees all adns state and reinitialises |
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it. It is highly recommended to only call this when there are no |
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outstanding requests. |
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|
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The first argument must currently be specified as C<undef>. |
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|
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The second argument can be missing or C<undef>; in which case the normal |
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initialisation is done (such as reading the F<resolv.conf>), or it might |
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be a stirng, in which case no config files or environment variables will |
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be read and the given string will be interpreted as the F<resolv.conf> |
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contents. |
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|
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=back |
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|
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=cut |
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|
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package EV::ADNS; |
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|
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use Carp (); |
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use EV (); |
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|
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BEGIN { |
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$VERSION = '3.0'; |
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|
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require XSLoader; |
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XSLoader::load (EV::ADNS, $VERSION); |
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} |
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|
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=head1 SEE ALSO |
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|
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L<EV>, L<Net::ADNS> another interface to adns, maybe better, but without |
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real support to integrate it into other event loops. |
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|
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=head1 AUTHOR |
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|
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Marc Lehmann <schmorp@schmorp.de> |
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http://home.schmorp.de/ |
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|
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=cut |
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1 |
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