da7d8e3763 | ||
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.. | ||
README.md | ||
cache.js | ||
index.js | ||
lookup.js | ||
memory.js | ||
package.json |
README.md
Cache
If you perform a query on an A or AAAA type and it doesn't exist, the cache will attempt to lookup a CNAME and then resolve that.
The constructor takes an optional object with the following properties:
store
-- implements the cache store model (optional, default MemoryStore)
Methods:
lookup(question, cb)
-- for a given question check the cache store for existencestore(packet)
-- iterates over the resource records in a packet and sends them to the cache storepurge()
-- clears the cache store of all entries
MemoryStore / Cache store model
MemoryStore(opts)
-- An in memory store based on a js object
Methods:
get(domain, key, cb)
domain
is the holder under which keys will be applied,key
is the subdomain that is being queried for. If youget('example.com', 'www', cb)
you are really asking forwww.example.com
.cb(err, results)
-- results is an object of types and array of answers
{ 1: [{address: '127.0.0.1', ttl: 300, type: 1, class: 1}] }
set(domain, key, data, cb)
domain
is the parent under which this key is stored.key
is the subdomain we are storing,data
is an object of types with an array of answers.
set('example.com', 'www', {1: [{class:1, type:1, ttl:300, address:'127.0.0.1'}]}, cb)
cb(err, data)
-- cb merely returns the data that was passed.
delete(domain[, key[, type]], cb)
-- delete all from a domain, a domain and key, or a domain a key and a type.
Lookup
Is a mechanism that given a store performs the common resolution pattern.
Given example.com
previous added to a store:
www.example.com CNAME foo.bar.example.com.
*.example.com A 127.0.0.1
A Lookup(store, 'example.com', {name:'www.example.com', type:1}, cb)
will resolve www
to the CNAME and then search for foo.bar.example.com
which
will return no results, and then search for *.bar.example.com
which will also
return no results, and ultimately searches for *.example.com
which will return
the desired record.
Callback will be called with (err, results)
where results is an array suitable
for use in Packet.answer