PersistantDataService

PersistantDataService

new PersistantDataService(server, route)

Description:

  • Implements a persistent data mechanism.

    • A POST service is attached to the given route.

    • This is the server side of a simple client/server mechanism for persistent data.

    • The local service is attached to an express web mechanism, using a construct of the form:

    // Loads required packages
const express = require("express");
const server = express();
const PersistantDataService = require("./PersistantDataService.js");

// Defines a minimal persistantData service
new PersistantDataService(server, "/_persitantData/upload");
server.listen(8080);
Parameters:
Name Type Default Description
server express

The express server mechanism.
route string /_persitantData/upload

The route, both :

  • The URL route to this service and
  • The local root directory path.

Methods

(inner) getQuery(query) → {string}

Description:

  • Implements the date file management query. The data file management queries are:

    • action=list[&format=json] :
      • Returns the data file base names list, separated \n.
    • action=load&file=data-file-base-name-without-extension[&format=json]&value=default-value :
      • Loads a file with a default-value if the file does not exists.
    • action=save&file=data-file-base-name-without-extension[&format=json]&value=value&backup=true-or-false :
      • Saves a value in a text file, with a git backup possibility.
    • action=unlink&file=data-file-base-name-without-extension :
      • Moves a data in the ./trash directory.
    • action=newid&where=true-or-false&when=true-or-false&suffix=suffix-string :
      • Returns new file ID built from : (i) the date in standard format, if when is true, (ii) the machine MAC address, if where is true, (iii) a suffix is not empty.
Parameters:
Name Type Description
query map.<string, string>

The HTTP query, as a structured map<string,string> object already parsed.
Returns:

The query response.

Type
string

(inner) getNewId(when, where, suffix)

Description:

  • Returns a new unique ID

Parameters:
Name Type Default Description
when true

If true

  • adds the current date and time in YYYY-MM-DDThh:mm:ss:msec standard format,
  • otherwise generates a unique integer for the given machine.
where false

If true adds the current machine MAC as localisation.
suffix

If defined, adds a suffix to the ID.
Returns:

The constructed ID.