flat-file-db
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Fast in-process flat file database that caches all data in memory
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# flat-file-db
Fast in-process flat file database for Node.js that supports JSON and caches all data in memory.
All data is persisted to an open file using a append-only algorithm ensuring compact file sizes and strong consistency.
npm install flat-file-db
[](http://travis-ci.org/mafintosh/flat-file-db)
## Usage
Pass a database file to use to the flat-file-db constructor and wait for the database to open.
When it is open all data has been loaded into memory.
``` js
var flatfile = require('flat-file-db');
var db = flatfile('/tmp/my.db');
db.on('open', function() {
db.put('hello', {world:1}); // store some data
console.log(db.get('hello')) // prints {world:1}
db.put('hey', {world:2}, function() {
// 'hey' is now fully persisted
});
});
```
If you don't want to wait for it to open use `flatfile.sync`
``` js
var db = flatfile.sync('/tmp/my.db');
console.log(db.get('hello')); // prints {world:1}
```
If you issue multiple writes the last one will always win
``` js
for (var i = 0; i < 10; i++) {
db.put('test', {count:i}, ...);
}
console.log(db.get('test')); // {count:9} which also the persisted value of 'test'
```
## API
* `db = flatfile(path, opts)` Create a new db instance. Per default fsync is called on all puts. To disable this set `opts.fsync = false`
* `db = flatfile.sync(path, opts)` Same as above except you do not need to wait for the open event
* `db.put(key, val, [cb])` Insert or update new key
* `db.del(key, [cb])` Delete a key
* `db.get(key) -> doc` Get the value of a key
* `db.has(key) -> bool` True if db has key
* `db.keys() -> list` Get all keys as an array
* `db.clear([cb])` Clears the database of all values
* `db.close()` Close the database
## Events
* `db.on('open')` Fired when the db is open and ready for use.
* `db.on('close')` Fired when the db is fully closed
* `db.on('drain')` All puts and deletes are flushed to disk
## License
MIT