DNS Query API Technical Docs

DNS Query API Technical Docs

This documentation covers some (not all) of the objects, methods and properties of the API. The code itself should be fairly easy to hack if more complex changes are required.

Class: DNSQuery

The main DNS API class.

property DNSQuery::server (string)

DNS server hostname or IP as a string

property DNSQuery::port (decimal)

Port to use (default 53)

property DNSQuery::timeout (decimal)

Timeout in seconds (default 60)

property DNSQuery::udp (bool)

Will use UDP if true else use TCP (default true)

property DNSQuery::debug (bool)

Output some debug information when querying (default false)

property DNSQuery::debugbinary (bool)

Dump binary debug output when querying (default false)

property DNSQuery::error (bool)

Set if the last query resulted in an error

property DNSQuery::lasterror (string)

Description of the last error encountered (null string if no error)

property DNSQuery::lastnameservers (Class::DNSAnswer)

Nameserver record results returned from the last query

property DNSQuery::lastadditional (Class::DNSAnswer)

Result records from the additional section of the last query

method DNSQuery::DNSQuery (hostname (string), [port=53 (decimal)], [timeout=60 (decimal)], [udp=true (bool)], [debug=false (bool)])

The constructor function - do not call this directly, rather use $object=new DNSQuery(options...) to create the object. Configuration can be changed after initilisation by setting the relevant property directly.

mixed method DNSQuery::Query (question (string), [type=A (string)])

Query the nameserver with the given question for the optionally specified type (defaults to A). The question string would normally consist of a hostname, domain name or IP address (in normal or IN-ADDR.ARPA form).

The query will be executed against the configured server using the set protocol (UDP if the udp property is true else TCP). If an error is encountered at any point the error property is set to true, a description placed in the lasterror property and the method returns false.

On successful completion of the query a Class::DNSAnswer is returned containing the records from the answer portion of the response. The class properties lastnameservers and lastadditional will be set as Class::DNSAnswer objects containing the resource records returned in the nameserver and additional portion of the answer respectively.

string method DNSQuery::SmartALookup (hostname (string))

Takes a hostname and returns an IP address or a null string if the query failed. Will recursively lookup aliases to a depth of 5.

Intended as a DNS server specific version of gethostbyname()

Class: DNSAnswer

property DNSAnswer::count (decimal)

Number of result records contained within the answer

property DNSAnswer::results (Class::DNSResult Array)

An array of Class::DNSResult objects containing each of the result records

Class: DNSResult

property DNSResult::type (decimal)

Decimal record type

property DNSResult::typeid (string)

String of the type (i.e. A, MX, SOA etc) or null string if an unknown type

property DNSResult::class (decimal)

Numeric result class type

property DNSResult::ttl (decimal)

Time-to-live (TTL) of resource record

property DNSResult::data (string|binary)

The processed output of a known type (the IP address for an A record, mail exchange for an MX record) or the binary data for an unknown type

property DNSResult::domain (string)

The domain/domain name/hostname the record applies to i.e. the hostname that the A record in the data type of an A lookup refers to

property DNSResult::string (string)

A textual representation of the answer (if the type is known else a null string) i.e. "www.fish.com has address 1.2.3.4"

property DNSResult::extras (string Array)

An array of any extra data available for the record if the type was known with a relevant key i.e. "level" for MX record mail exchange priorities. See the main documentation for a full list of extra type-dependent data.