elda-ai Memory

Methods for external memory storage.

In the structure of elda-ai memory is considered as long term storage of information.

Development

Running tests:

npm install
npm test

API

Configure

When you require elda-ai-memory, it returns a function that can be used to configure a memory interface.

The stub configuration is:

var config = {
  type: 'none';
};

Where as a configuration using git is:

var config =  {
  type: 'git',
  remote: '[email protected]:elda-ai/memory-training.git',
  local: process.cwd() + '/memory',
  user: {
    name: 'elda-ai',
    email: '[email protected]'
  }
};

Pass the config into the memory function to return a promise. The promise resolves to a usable instance. During this step, files are downloaded from the remote and stored locally; this may take several seconds depending on the size of the remote.

var memory = require('elda-ai-memory');
memory(config).then(function(instance) {
  /* ... do stuff with instance ... */
});

• If there is an error with the supplied config, it should fail fast with a rejected promise.
• External memory is treated as a local copy which upon which you can read and write. Later store can be used to push changes, and destroy used to clean up the local copy.

Read

External memory is expected to be made up of files. These files can be read from the local copy using a relative path to the root of the external files.

var memory = require('elda-ai-memory');
memory(config).then(function(instance) {
  return instance.read('file/name.json').then(function(contents) {
    console.log('Read from file:', contents);
  });
});

Write

Files can be created and updated by using write. Writing will only update the local copy until store is called.

var memory = require('elda-ai-memory');
memory(config).then(function(instance) {
  // Write a file
  var data = JSON.stringify({data: "some data"});
  return instance.write('file/new.json', data).then(function(name) {
    console.log('Wrote to file:', name);
  });
});

Delete

Files can be deleted from the local memory. Deleted files will only affect the remote when store is called.

var memory = require('elda-ai-memory');
memory(config).then(function(instance) {
  // Delete a file
  return instance.delete('file/to/delete.json').then(function(name) {
    console.log('Deleted file:', name);
  });
});

Store

Store pushes any local changes to the remote location with a message.

var memory = require('elda-ai-memory');
memory(config).then(function(instance) {
  // Store local changes back to server
  var message = 'New files added';
  return instance.store(message).then(function() {
    console.log('Files stored in external memory:', message);
  });
});

Destroy

Destroy removes all local files stored on the machine relating to the remote.

var memory = require('elda-ai-memory');
memory(config).then(function(instance) {
  // Destroy local copy of files
  return instance.destroy().then(function() {
    console.log('Local files removed');
  });
});

Git configuration

This configuration assumes you have the command line version of git installed on the machine, and that you have correct access rights to the remote repository.

Worked example:

var memory = require('elda-ai-memory');
var config =  {
  type: 'git',
  remote: '[email protected]:elda-ai/memory-training.git',
  local: process.cwd() + '/memory',
  user: {
    name: 'elda-ai',
    email: '[email protected]'
  }
};

// Retrieve files from external memory
memory(config).then(function(instance) {

  function readAFile() {
    // Read a file
    return instance.read('file/name.json').then(function(contents) {
      console.log('Read from file:', contents);
    });
  }

  function writeAFile() {
    // Write a file
    var data = JSON.stringify({data: "some data"});
    return instance.write('file/new.json', data).then(function(name) {
      console.log('Wrote to file:', name);
    });
  }

  function deleteAFile() {
    // Delete a file
    return instance.delete('file/to/delete.json').then(function(name) {
      console.log('Deleted file:', name);
    });
  }

  function storeChanges() {
    // Store local changes back to server
    var message = 'New files added';
    return instance.store(message).then(function() {
      console.log('Files stored in external memory:', message);
    });
  }

  function destroyLocalCopy() {
    // Destroy local copy of files
    return instance.destroy().then(function() {
      console.log('Local files removed');
    });
  }

  return readExample()
    .then(readAFile)
    .then(writeAFile)
    .then(deleteAFile)
    .then(storeChanges)
    .then(destroyLocalCopy);
});