Synopsis
EventVat is an evented in-process key/value store with an API like that of Redis. It's event based, which means that when a method is called that affects the data, corresponding events will be raised. It supports 5 data types, Strings, Numbers, Booleans, Arrays and Hashes.
Motivation
- A datastore for small, volitile working sets
- For processes who do not share data, it reduces unnecessary trips across the process boundary.
- Portability, works in the browser and on the server.
- Write to any storage end-point (such as local browser storage, a filesystem or couchdb).
Installation
$npm install eventvat
Usage
Each new instance of EventVat
is a hash. There are lots of convenient methods attached to each new instance.
events
EventVat uses EventEmitter2. Listeners can attached to an EventVat object. An EventVat object can emit and event and a listener will respond. An event has three characteristics, the event name, a listener and an associated data key or wildcard.
var vat = EventVat();
vat.on('get foo', function(key, value) {
console.log('`' + key + '` has the value: `' + value + '`');
});
vat.set('foo', 'hello, world');
vat.get('foo');
API
instance methods
publish()
Synonymous with EventEmitter2.prototype.emit
subscribe()
Synonymous with EventEmitter2.prototype.on
unsubscribe()
Synonymous with EventEmitter2.prototype.removeListener
die(key)
Expire a key
del(key /* ... */)
Delete a key
exists(key)
Determine if a key exists
expire(key, ttl)
Set a key's time to live in seconds
expireat(key, dueDate)
Set the expiration for a key as a UNIX timestamp
keys(regex)
Find all keys matching the given pattern
move(key, db)
Move a key to another database
object(subcommend /* ... */)
Inspect the internals of an object
persist(key)
Remove the expiration from a key
randomkey()
Return a random key from the keyspace
rename(oldKey, newKey)
Rename a key
renamenx(oldKey, newKey)
Rename a key, only if the new key does not exist
sort()
Sort the elements in a list, set or sorted set
type(key)
Determine the type stored at key
ttl(key)
Get the time to live for a key
append(key, value)
Append a value to a key
decr(key)
Decrement the integer value of a key by one
decrby(key, value)
Decrement the integer value of a key by the given number
get(key)
Get the value of a key
getbit(key)
Returns the bit value at offset in the string value stored at key
getrange(key, start, end)
Get a substring of the string stored at a key
getset(key, value)
Set the string value of a key and return its old value
incr(key)
Increment the integer value of a key by one
incrby(key, value)
Increment the integer value of a key by the given number
mget(key /* ... */)
Get the values of all the given keys
mset(keys /* ... /, values / ... */)
Set multiple keys to multiple values
msetnx(keys /* ... /, values / ... */)
Set multiple keys to multiple values, only if none of the keys exist
set(key, value, ttl)
Set the string value of a key
setbit(key, offset, value)
Sets or clears the bit at offset in the string value stored at key
setex(key, seconds, value)
Set the value and expiration of a key
setnx(key, value, ttl)
Set the value of a key, only if the key does not exist
setrange(key, offset, value)
Overwrite part of a string at key starting at the specified offset
strlen(key)
Get the length of the value stored in a key
hdel(key, field /* ... */)
Delete one or more hash fields
hexists(key, field)
Determine if a hash field exists
hget(key, field)
Get the value of a hash field
hgetall(key)
Get all the fields and values in a hash
hincr(key, field)
Increment the integer value of a hash field by one
hincrby(key, field, value)
Increment the integer value of a hash field by the given number
hdecr(key, field)
Decrement the integer value of a hash field by one
hdecrby(key, field, value)
Decrement the integer value of a hash field by the given number
hkeys(key)
Get all the fields in a hash
hlen(key)
Get the number of fields in a hash
hmget(key, field /* ... */)
Get the values of all the given hash fields
hmset(key, fields /* ... /, values / ... */)
Set multiple hash fields to multiple values
hset(key, field, value)
Set the string value of a hash field
hsetnx(key, field, value /* ... */)
Set the value of a hash field, only if the field does not exist
hvals(key)
Get all the values in a hash
dump(stringify)
Dump the current data store into a string
swap(a, b, depth)
Swap two values
findin(key, value)
Search within the value of a key
Tests
$npm test
(The MIT License)
Copyright (c) 2010 hij1nx http://www.twitter.com/hij1nx
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE DBSIZEORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.