kvstore

kvstore is a key value store implemented as a wrapper around Mnesia. Its distinctive feature is tracking access times.

Summary

kvstore uses Mnesia to store data. It defines the following fields:

• key
• time_created
• time_modified
• time_accessed
• value

Access times are tracked in time_accessed field.

Installation

The obvious preprequisite for kvstore is the Erlang runtime. To install:

• clone this project and cd into its directory

• compile

  `erl -make`
  

• to install with 2 nodes called kv1 and kv2 start Erlang shell in 2 different shells

  `shell1> erl -pa ebin/ -sname kv1@localhost`  
  `shell2> erl -pa ebin/ -sname kv2@localhost`
  

• link kv2 to kv1 - i.e. in kv2 shell type

  `net_kernel:connect_node('kv1@localhost').`
  

• install on all linked nodes - from either node run

  `kvstore:install_all_nodes().`
  

• installation is now complete

Tests

To run tests, change into the project directory and run:

ct_run -pa ebin/ -spec kvstore.spec

Run

To run the kvstore server:

• start the Erlang shell on each host or Mnesia instance

  `shell1> erl -pa ebin/ -sname kv1@localhost`  
  `shell2> erl -pa ebin/ -sname kv2@localhost`
  

• connect each instance - i.e. on all instances except the first:

  `net_kernel:connect_node('kv1@localhost').`
  

• start applications on all instances:

  `application:start(mnesia).`  
  `application:start(kvstore).`
  

Basic Usage

After starting the server as above, you can run commands from shell to operate on the data:

• to write data

  `kvstore:write("key-1", "value-1").`
  

• to read data by key

  `kvstore:read("key-1").`
  

• to delete data by key

  `kvstore:delete("key-1").`
  

Advanced Usage

Coming soon...