Metadata-Version: 2.1
Name: freaddb
Version: 0.0.6
Summary: Fast Read DB
Home-page: https://github.com/phucty/freaddb
License: MIT and The OpenLDAP Public License
Author: Phuc Nguyen
Author-email: phucnt.ty@gmail.com
Requires-Python: >=3.8,<4.0
Classifier: License :: Other/Proprietary License
Classifier: Programming Language :: Python :: 3
Classifier: Programming Language :: Python :: 3.10
Classifier: Programming Language :: Python :: 3.8
Classifier: Programming Language :: Python :: 3.9
Requires-Dist: lmdb (>=1.3.0,<2.0.0)
Requires-Dist: lz4 (>=4.0.1,<5.0.0)
Requires-Dist: msgpack (>=1.0.4,<2.0.0)
Requires-Dist: numpy (>=1.22.4,<2.0.0)
Requires-Dist: psutil (>=5.9.4,<6.0.0)
Requires-Dist: pyroaring (>=0.3.3,<0.4.0)
Requires-Dist: tqdm (>=4.64.0,<5.0.0)
Requires-Dist: ujson (>=5.3.0,<6.0.0)
Project-URL: Repository, https://github.com/phucty/freaddb
Description-Content-Type: text/markdown

# FReadDB

FReadDB: Fast Read Database is implemented with LMDB (key-value database) as the underlying storage. We use this DB as a data storage, and RAM of [MTab system](https://mtab.kgraph.jp).

## Installation

```bash
pip install freaddb
```

## Usage

```python
from freaddb.db_lmdb import SIZE_1GB, DBSpec, FReadDB, ToBytes

# Data file directory
data_file = "/tmp/freaddb/db_test_basic"
# Clear old data
shutil.rmtree(data_file, ignore_errors=True)

# Define sub database schema
data_schema = [
    # keys are strings, values are python objs and compress values
    DBSpec(
        name="data0",
        integerkey=False,
        bytes_value=ToBytes.OBJ,
        compress_value=True,
    ),
    # key are integers, values are python objects serialized with msgpack and no compress values
    DBSpec(name="data1", integerkey=True, bytes_value=ToBytes.OBJ),
    # key are strings, values are python objects serialized with pickle
    DBSpec(name="data2", integerkey=False, bytes_value=ToBytes.PICKLE),
    # key are strings, values are bytes
    DBSpec(name="data3", integerkey=False, bytes_value=ToBytes.BYTES),
    # key are integers, values are list integers serialized with numpy
    DBSpec(name="data4", integerkey=True, bytes_value=ToBytes.INT_NUMPY),
    # key are integers, values are list integers serialized with BITMAP
    DBSpec(name="data5", integerkey=True, bytes_value=ToBytes.INT_BITMAP),
    # key are combination of two integers
    DBSpec(name="data6", integerkey=True, combinekey=True),
    # key are combination of three integers
    DBSpec(
        name="data7",
        integerkey=True,
        combinekey=True,
        combinelen=3,
    ),
]

# Example data
data = {
    "data0": {"One": {1: "One"}, "Two": {2: "Two"}},
    "data1": {1: "One", 2: "Two"},
    "data2": {"One": 1, "Two": 2},
    "data3": {"One": b"1", "Two": b"2"},
    "data4": {i: list(range(i * 10)) for i in range(10, 20)},
    "data5": {i: list(range(i * 10)) for i in range(10, 20)},
    "data6": {(1, 2): "One", (2, 3): "Two"},
    "data7": {(1, 2, 3): "One", (2, 3, 4): "Two"},
}
to_list_data = {"data4", "data5"}

# Create data with data_file, data_schema, and buffer is 1GB
db = FReadDB(db_file=data_file, db_schema=data_schema, buff_limit=SIZE_1GB)

# Add data to FReadDB
for data_name, data_items in data.items():
    for key, value in data_items.items():
        db.add_buff(data_name, key, value)
# db.delete_buff("data0", "One")

# Make sure save all buffer to disk
db.save_buff()

####################################################
# (Optional for readonly database) Compress database
db.compress()
db.close()
db = FReadDB(db_file=data_file, readonly=True)
####################################################

# Access data
# Get a key
sample = db.get_value("data1", 1)
assert sample == "One"

# Get many keys
for data_name, data_samples in data.items():
    sample = db.get_values(data_name, list(data_samples.keys()))
    if data_name in to_list_data:
        sample = {k: list(v) for k, v in sample.items()}
    assert sample == data_samples
```

