Ecosyste.ms: Awesome
An open API service indexing awesome lists of open source software.
https://github.com/maiha/rocksdb.cr
RocksDB client for Crystal
https://github.com/maiha/rocksdb.cr
Last synced: about 2 months ago
JSON representation
RocksDB client for Crystal
- Host: GitHub
- URL: https://github.com/maiha/rocksdb.cr
- Owner: maiha
- License: mit
- Created: 2016-11-25T18:33:46.000Z (almost 8 years ago)
- Default Branch: main
- Last Pushed: 2024-01-13T04:47:36.000Z (8 months ago)
- Last Synced: 2024-06-21T18:09:50.809Z (3 months ago)
- Language: Crystal
- Size: 61.5 KB
- Stars: 38
- Watchers: 5
- Forks: 8
- Open Issues: 4
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
- awesome-crystal - rocksdb.cr - RocksDB client (Database Drivers/Clients)
- awesome-crystal - rocksdb.cr - RocksDB client (Database Drivers/Clients)
- awesome-crystal - rocksdb.cr - RocksDB client (Database Drivers/Clients)
README
# rocksdb.cr [](https://travis-ci.org/maiha/rocksdb.cr)
RocksDB client for [Crystal](http://crystal-lang.org/).
- crystal: `0.27.2` .. `1.11.1`
## Supported API
See [API](./API.md)
## Installation
Add this to your application's `shard.yml`:
```yaml
dependencies:
rocksdb:
github: maiha/rocksdb.cr
version: 1.2.0
```
## Usage
```crystal
require "rocksdb"
db = RocksDB::DB.new("tmp/db1")
db.put("foo", "1")
db.get("foo") # => "1"
db.delete("foo")
db.get("foo") # => ""
db.get?("foo") # => nil
db.get!("foo") # raise RocksDB::NotFound.new("foo")
db.close
```
### readonly mode
```crystal
db = RocksDB::DB.new("tmp/db1", readonly: true)
# or RocksDB::DB.read("tmp/db1")
db.put("foo", "1") # raise RocksDB::Error("Not supported operation in read only mode.")
```
### Iterations
```crystal
3.times{|i| db.put("k#{i}", i) }
db.keys # => ["k0","k1","k2"]
db.keys(2) # => ["k0","k1"]
db.each do |k,v|
...
```
### Iterator
```crystal
iter = db.new_iterator
iter.key # => "k0"
iter.next
iter.value # => "1"
iter.first
iter.key # => "k0"
iter.seek("k2")
iter.next
iter.valid? # => false
iter.close # memory leaks when you forget this
```
- same as `each`
```crystal
iter = db.new_iterator
iter.first
while (iter.valid?)
# yield {iter.key, iter.value}
iter.next
end
iter.close # memory leaks when you forget this
```
### binary data
Although all data are stored as Binary in RocksDB,
return value will be converted to String when accessed by String key.
```crystal
db.put(Bytes[0], Bytes[9])
db.get(Bytes[0]) # => Bytes[9]
db.get("\u{0}") # => "\t"
```
#### binary iterator
`binary_XXX` is available to treat data as binary
- `binary_keys`
- `binary_each`
- `new_binary_iterator`
```crystal
db.keys # => ["\t"]
db.binary_keys # => [Bytes[9]]
```
### database options
- `options` for opening database
- `read_options` for reading data
- `write_options` for writing data
```crystal
opts = RocksDB::Options.new
opts.set_create_if_missing(1)
ropts = RocksDB::ReadOptions.new
ropts.set_verify_checksum(1)
wopts = RocksDB::WriteOptions.new
wopts.set_sync(1)
wopts.disable_wal(1)
db = RocksDB::DB.new("tmp/db1", options: opts, read_options: ropts, write_options: wopts)
```
- all options: [options.cr](./src/rocksdb/options.cr)
## Roadmap
#### 0.5.0
- [x] Iterations for Binary
## Testing
- Now Travis CI is ready by https://github.com/maiha/rocksdb.cr/pull/3
## Contributing
1. Fork it ( https://github.com/maiha/rocksdb.cr/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request
## Contributors
- [maiha](https://github.com/maiha) maiha - creator, maintainer