(FFOS Gaia) Telemetry - AUM分析

　　AUM是App Usage Metrics的缩写，用于统计FFOS中一些应用的使用情况，并且在用户允许的情况下(Settings中设置)，将统计信息上报Telemetry Server。

　　

1. AUM会监控FFOS中的几种应用。

•   Apps pre-installed with the phone (certified, or using a gaia origin)
•   Apps installed from the marketplace

2. Telemetry Server Path

　　http://{host}:{port}/{deviceID}/{reason}/{appName}/{appVersion}/{appUpdateChannel}/{appBuildID}

3. AUM消息格式

　　以下是讲flame手机中的AUM功能打开，添加log打印出来的消息格式。

{
    "ver":1,
    "info":{
        "start":1437968681114,
        "apps":{
        },
        "searches":{
        },
        "stop":1437968928832,
        "deviceID":"7a0f9f11-c8de-421d-939b-878b7e89915e",
        "locale":"en-US",
        "screen":{
            "width":320,
            "height":569,
            "devicePixelRatio":1.5
        },
        "deviceinfo":{
            "developer.menu.enabled":true,
            "deviceinfo.hardware":"qcom",
            "deviceinfo.os":"2.5.0.0-prerelease",
            "deviceinfo.product_model":"flame",
            "deviceinfo.software":"Boot2Gecko 2.5.0.0-prerelease"
        },
        "simInfo":{
            "network":null,
            "icc":null
        },
        "reason":"appusage",
        "appName":"FirefoxOS",
        "appUpdateChannel":"nightly",
        "appBuildID":"20150723141330",
        "appVersion":"42.0a1"
    }
}

 　　info->apps字段是关于per-app的信息，参考代码，其消息格式是:

{
    "per-app-manifestURL-1":{
        "yyyymmdd":{
            "usageTime":0,
            "invocations":0,
            "installs":0,
            "uninstalls":0,
            "activities":{
            }
        }
    },
    "per-app-manifestURL-2":{
        "yyyymmdd":{
            "usageTime":0,
            "invocations":0,
            "installs":0,
            "uninstalls":0,
            "activities":{
            }
        }
    }
}

　　info->searches字段是关于per-search的信息，参考代码，其消息格式是:

{
    "per-app-provider-1":{
        "yyyymmdd":{
            "count":0
        }
    },
    "per-app-provider-2":{
        "yyyymmdd":{
            "count":0
        }
    }
}

 4. AUM upload policy

　　FFOS中预设的是2 weeks upload。

 5. code分析

　　代码比较简单，以后有时间再贴出详细分析(代码位置:gaia/apps/system/js/app_usage_metrics.js)。