Call Monitor

Simple Android application for serving data about phone calls via REST API in a local network.

Features

• REST API server:
  • Metadata about server start time and available endpoints.
  • Information about current phone call.
  • Information about previous phone calls from the launch of the app.
• Foreground service:
  • Keeps API server available.
  • Displays ongoing notification.
• Graphical user interface:
  • Displays local IP address and port for server.
  • Displays call log history.
  • Allows to start/stop of API service.

NOTE

Handling more than one call at the same time is not supported due to limitations of android.intent.action.PHONE_STATE broadcast receiver, which does not provide information about second ongoing call end or switching between two ongoing calls.

API

GET /

Provides metadata about server start time and available endpoints.

Example response:

{
  "start": "2023-08-28T18:18:49+02:00",
  "services": [
    {
      "name": "status",
      "uri": "http://0.0.0.0:12345/status"
    },
    {
      "name": "log",
      "uri": "http://0.0.0.0:12345/log"
    }
  ]
}

GET /status

Provides information about current phone call. Additionally, each call is incrementing timesQueried value but only for ongoing calls.

Example responses:

The empty JSON if there is no phone call currently:

{}

Incoming call "ringing":

{
  "time": "2023-08-28T18:18:49+02:00",
  "outgoing": false,
  "ongoing": false,
  "number": "6505551212",
  "name": null
}

Incoming call "offhook":

{
  "time": "2023-08-28T18:18:49+02:00",
  "outgoing": false,
  "ongoing": true,
  "number": "6505551212",
  "name": null
}

Outgoing call:

{
  "time": "2023-08-28T18:18:49+02:00",
  "outgoing": false,
  "ongoing": true,
  "number": "6505551212",
  "name": null
}

NOTES:

• The name value can be null if the phone number is not named in the phone book.
• Outgoing calls always have the value ongoing set as true.

GET /log

Provides information about phone calls.

Example response:

[
  {
    "beginning": "2023-08-27T15:28:50+02:00",
    "duration": 26,
    "number": "+48500444555",
    "name": "Test",
    "timesQueried": 5
  },
  {
    "beginning": "2023-08-27T15:20:22+02:00",
    "duration": 0,
    "number": "+48500444555",
    "name": "Test",
    "timesQueried": 0
  },
  {
    "beginning": "2023-08-27T15:20:06+02:00",
    "duration": 25,
    "number": "6505551212",
    "name": null,
    "timesQueried": 0
  }
]

Development

The following section describes how to test the application's HTTP server during development.

To connect to the server from the host machine while the app is running on an emulator is needed to forward the port via adb:

adb forward tcp:12345 tcp:12345

For getting server metadata, execute:

curl -v localhost:12345

For getting status about current connection metadata, execute:

curl -v localhost:12345/status

For getting status about call log, execute:

curl -v localhost:12345/log