
"core" ping
============

This mobile-specific ping is intended to provide the most critical
data in a concise format, allowing for frequent uploads.

Since this ping is used to measure retention, it should be sent
each time the browser is opened.

Submission will be per the Edge server specification::

    /submit/telemetry/docId/docType/appName/appVersion/appUpdateChannel/appBuildID

* ``docId`` is a UUID for deduping
* ``docType`` is “core”
* ``appName`` is “Fennec”
* ``appVersion`` is the version of the application (e.g. "46.0a1")
* ``appUpdateChannel`` is “release”, “beta”, etc.
* ``appBuildID`` is the build number

Note: Counts below (e.g. search & usage times) are “since the last
ping”, not total for the whole application lifetime.

Structure::

    {
      "v": 1, // ping format version
      "clientId": <string>, // client id, e.g.
                            // "c641eacf-c30c-4171-b403-f077724e848a"
      "seq": <positive integer>, // running ping counter, e.g. 3
      "locale": <string>, // application locale, e.g. "en-US"
      "os": <string>, // OS name.
      "osversion": <string>, // OS version.
      "device": <string>, // Build.MANUFACTURER + " - " + Build.MODEL
                          // where manufacturer is truncated to 12 characters
                          // & model is truncated to 19 characters
      "arch": <string>, // e.g. "arm", "x86"
      "profileDate": <pos integer>, // Profile creation date in days since
                                    // UNIX epoch.

      "experiments": [<string>, …], // Optional, array of identifiers
                                    // for the active experiments
    }

The ``device`` field is filled in with information specified by the hardware
manufacturer. As such, it could be excessively long and use excessive amounts
of limited user data. To avoid this, we limit the length of the field. We're
more likely have collisions for models within a manufacturer (e.g. "Galaxy S5"
vs. "Galaxy Note") than we are for shortened manufacturer names so we provide
more characters for the model than the manufacturer.

