HDF REST server

HDF REST server is a simple RESTful service for HDF5 data stores .

What is HDFdata store?

HDF5 is a data model, library, and file format for storing and managing data. HDF5 is suitable for handling large datasets. HDF5 file sizes are much smaller than other comparable data files. And it is superior to mySQL in terms of read/write speed. learn more here

Description:

The current implementation provides a RESTful interface to view contents of HDF5 data stores. Proving you the ability to query your data store like localhost/q/HDFfile/table/LIMIT/chunkNum. These data files need to be located in a predefined Directory. GET request are currently handled. In later updates PUT, POST, DELETE request will be implemented to allow creating/modifying data stores using the RESTful interface.

Getting started

This Package has the following requirements:

• pandas, and pytables for data handling
• Flask, as the http server
• Flask-restful , to install use: pip install flask-restful

Install

To install simply run:

    python setup.py install

Lets Now Run the REST server.

Via code

import HDFserver
HDFserver.run(port=7000,...)

Via Command Line

You can use one of following commands to start the server

python HDFserver.py

Setting parameters

You can set data directory by supplying data_dir argument. All the usual arguments handled by flask can be included .

python HDFserver.py -data_dir=DATA_DIR -port=7000 -host=127.0.0.1

Basic Usage

First thing first we need to edit DATA_DIR in the configs.py. This should be the directory where your HDF5 data stores are located. Alternativly, if you are using the runnig the server via the api you can use set_data_dir method :

import HDFserver
HDFserver.set_data_dir( directory )

REST API endpoints

Consuming

To get a list of hdf5 stores:

    /stores_/

To list keys in the hdf5 file. Where is the hdf5 file with the extension dropped:

    /keys/<filename>/

To retreive data for rows 0 to 99 from table1 in the hdf5 file test.h5:

    /test/table1/100/0/

Example

    import requests

    print requests.get("http://127.0.0.1:5000/test/table1/100/1").json()

Returns:

    {u'table1': u'{"0":{"0":0.7429897161,"1":0.8484121687,"2":0.5145762482,"3":0.1149139957,"4":0.8896877559},
    "1":{"0":0.8473583747,"1":0.7616489838,"2":0.9482270932,"3":0.7261994593,"4":0.6119108996},
    "2":{"0":0.6861526421,"1":0.0728248119,"2":0.3953423794,"3":0.4815486616,"4":0.6398098313}
    }
    }

Author

Yohannes Libanos