strichliste

This module is the API for the strichliste app. Arbitrary clients can be implemented using this API

Clients:

• Web-Frontend (demo)

TOC

• First Steps
• Configuration
• API Documentation

First Steps

Setup

Steps

Grap the latest release

install dependencies

$ make install-packages

run tests

$ make test

initialize database

creates the tables in the sqlitefile

$ make database

everything at once

For your convenience the following make target does all of the above steps at once:

$ make setup

start api server

Consider editing the configuration before starting the api server (see the configuration section).

$ make start

Configuration

The API server brings with it a default configuration which can be found in /configuration/default.js. This default can be used to setup your own configuration. The server utilizes the configurations module from npm which does a staged modification of configurations. Initially the default config is loaded and then subsequent modifications are applied.

You can add your own environment specific configuration by adding e.g. a production.js to the configurations folder. When the server is started with the node environment NODE_ENV set to production, the default config is enhanced by your production config. You don't have to specify each and every key from default.js, the defaults are retained.

You also can specify an external configuration sitting on an arbitrary place in your system by assigning it via a command line parameter:

$ node server.js --externalconfig=/etc/opt/strichliste/myconfig.js

Configuration details

This section explains the content of the default.json which can be modified by you as you wish

module.exports = {
    //the server runs on this port
    port: 8080,

    //details to the database
    database: {
        //the engine that should be used, until now only sqlite is supported
        type: 'SQLITE',

        //(arbitrary) options to the database engine
        options: {
            filename: 'data.sqlite'
        }
    },

    //strichliste announces actions via mqtt if desired
    mqtt: {
        //enable mqtt broadcasting
        enabled: false,

        //the mqtt service host
        host: 'localhost',

        // the mqtt service port
        port: 1883,

        //a list of topics that are broadcasted
        topics: {
            //gets broadcasted when someone adds a new transaction
            transactionValue: 'strichliste/transactionValue'
        }
    },

    //boundaries define values the apply to a user account or the transactions of auser
    boundaries: {
        account: {
            //the maximum amount that can be stored in a user's account (99999999 is equvalent to Inifinity)
            upper: 99999999,

            //the maximum dept a user can have
            lower: -50
        },
        transaction: {
            //the biggest transaction a user can do
            upper: 150,

            //the biggest money withdrawal a user can do
            lower: -20
        }
    },

    //logging
    logging: {
        //specifies if the api should log api access to the console
        active: true
    }
}

API Documentation

Every API answer has the Content-Type application/json. Data that is posted to the API is always JSON as well.

Pagination

At some endpoints the following queryparameters can be used to control the pagination of lists:

• limit: the number of items to show
• offset: the number of the first item in the list

Each of the paginated lists are of the following data structure:

{
  overallCount: <int>,
  limit: <int>,
  offset: <int>,
  entries: [<entry]
}

Endpoints

GET /user

Returns the complete list of all users. Each user is described via the following data structure:

{
  "id": <int>,
  "name": <string>,
  "balance": <float>,
  "lastTransaction": <dateTime>
}

The parameters and the list structure of the Pagination section are used in this endpoint.

POST /user

Creates a new user. To create a new user a name has to be assigned via the following data structure:

{ "name": <string> }

Returns the status code 201 and the created user if the creation was successfull.

Errors

• 409: If a user already exists

GET /transaction

Lists the latest transactions. Each transaction has the following data structure:

{
  id: <int>,
  userId: <int>,
  createDate: <DateTime>,
  value: <float>
}

Use the parameters and the list structure of the Pagination section to specify the list's structure.

GET /user/:userId

Returns one specific user. The returned data structure correlates with the /user endpoint, additionally a list of the five last transactions is sent. (See the /user/transaction section for a reference to the transaction data structure)

Errors

• 404: If the user could not be found

GET /user/:userId/transaction

Returns a list of transactions belonging to the user with the id :userId. The structure of the transactions object corresponds to the definiton of the '/transaction' route

The parameters and the list structure of the Pagination section are used in this endpoint.

Errors

• 404: If the user could not be found

POST /user/:userId/transaction

Creates a new transaction for the user with the id :userId. The following data structure describes the transaction:

{ value: <float> }

Returns the status code 201 if a transaction was successfully created.

Errors

• 400: If a transaction value is not a number or is zero.
• 403: If a transaction value is above or below a certain border (configurable) or the resulting user balance would exceed a certain border (configurable).
• 404: If the user has not been found

GET /user/:userId/transaction/:transactionId

Returns a certain transaction. The data structure corresponds to that of the /user/:userId/transaction section.

Errors

• 404: If the user or the transaction could not be found

GET /settings

Returns the configured settings:

{
  boundaries: {
    upper: <int>
    lower: <int>
  }
}

For more details on the configuration see the configuration section.

GET /metrics

Returns metrics concerning the registered users and their transactions. Data structure:

{
  overallBalance: <float>,
  countTransactions: <int>,
  contUsers: <int>,
  avgBalance: <float>,
  days: [
    {
      date: <Date>,
      overallNumber: <int>,
      distinctUsers: <int>,
      dayBalance: <float>,
      dayBalancePositive: <float>,
      dayBalanceNegative: <float>
    }
  ]
}