# cache_stats

Retrieves detailed, aggregated statistics for caches in a specific CDN.

This gives an aggregate of statistics for all caches within a particular CDN and time range. For statistics basic statistics from all caches regardless of CDN and at the current time, use caches/stats.

## GET

Retrieves statistics about the caches within the CDN

Auth. Required

Yes

Roles Required

None

Response Type

Object

## Request Structure

Table 252 Request Query Parameters

Name

Required

Description

cdnName

yes

The name of a CDN. Results will represent caches within this CDN

endDate

yes

The date and time until which statistics shall be aggregated in RFC 3339 format (with or without sub-second precision), the number of nanoseconds since the Unix Epoch, or in the same, proprietary format as the lastUpdated fields prevalent throughout the Traffic Ops API

exclude

no

Either “series” to omit the data series from the result, or “summary” to omit the summary data from the result - directly corresponds to fields in the Response Structure

interval

no

Specifies the interval within which data will be “bucketed”; e.g. when requesting data from 2019-07-25T00:00:00Z to 2019-07-25T23:59:59Z with an interval of “1m”, the resulting data series (assuming it is not excluded) should contain $$24\frac{\mathrm{hours}}{\mathrm{day}}\times60\frac{\mathrm{minutes}}{\mathrm{hour}}\times1\mathrm{day}\times1\frac{\mathrm{minute}}{\mathrm{data point}}=1440\mathrm{data\;points}$$ The allowed values for this parameter are valid InfluxQL duration literal strings matching ^d+[mhdw]\$

limit

no

A natural number indicating the maximum amount of data points should be returned in the series object

metricType

yes

The metric type being reported - one of: ‘connections’, ‘bandwidth’, ‘maxkbps’

offset

no

A natural number of data points to drop from the beginning of the returned data set

orderby

no

Though one struggles to imagine why, this can be used to specify “time” to sort data points by their “time” (which is the default behavior)

startDate

yes

The date and time from which statistics shall be aggregated in RFC 3339 format (with or without sub-second precision), the number of nanoseconds since the Unix Epoch, or in the same, proprietary format as the lastUpdated fields prevalent throughout the Traffic Ops API

#598 Request Example
GET /api/3.0/cache_stats?cdnName=CDN&endDate=2019-10-28T20:49:00Z&metricType=bandwidth&startDate=2019-10-28T20:45:00Z HTTP/1.1
User-Agent: python-requests/2.20.1
Accept-Encoding: gzip, deflate
Accept: application/json;timestamp=unix, application/json;timestamp=rfc;q=0.9, application/json;q=0.8, */*;q=0.7
Connection: keep-alive


### Content Format

It’s important to note in Request Example the use of a complex “Accept” header. This endpoint accepts two special media types in the “Accept” header that instruct it on how to format the timestamps associated with the returned data. Specifically, Traffic Ops will recognize the special, optional, non-standard parameter of application/json: timestamp. The values of this parameter are restricted to one of

rfc

Returned timestamps will be formatted according to RFC 3339 (no sub-second precision).

unix

Returned timestamps will be formatted as the number of nanoseconds since the Unix Epoch (midnight on January 1st 1970 UTC).

Implementation Detail

The endpoint passes back nanoseconds, specifically, because that is the form used both by InfluxDB, which is used to store the data being served, and Go’s standard library. Clients may need to convert the value to match their own standard libraries - e.g. the Date() class in Javascript expects milliseconds.

The default behavior - when only e.g. application/json or */* is given - is to use RFC 3339 formatting. It will, however, respect quality parameters. It is suggested that clients request timestamps they can handle specifically, rather than relying on this default behavior, as it is subject to change and is in fact expected to invert in the next major release as string-based time formats become deprecated.

## Response Structure

series

An object containing the actual data series and information necessary for working with it.

columns

This is an array of names of the columns of the data contained in the “values” array - should always be ["time", "sum_count"]

count

The number of data points contained in the “values” array

name

The name of the data set. Should always match metric.ds.1min where metric is the requested metricType

values

The actual array of data points. Each represents a length of time specified by the interval query parameter

time

The time at which the measurement was taken. This corresponds to the beginning of the interval. This time comes in the format of either an RFC 3339-formatted string, or a number containing the number of nanoseconds since the Unix Epoch depending on the “Accept” header sent by the client, according to the rules outlined in Content Format.

value

The value of the requested metricType at the time given by time. This will always be a floating point number, unless no data is available for the data interval, in which case it will be null

summary

A summary of the data contained in the “series” object

average

The arithmetic mean of the data’s values

count

The number of measurements taken within the requested timespan. This is, in general, not the same as the count field of the series object, as it reflects the number of underlying, un-“bucketed” data points, and is therefore dependent on the implementation of Traffic Stats.

fifthPercentile

Data points with values less than or equal to this number constitute the “bottom” 5% of the data set

max

The maximum value that can be found in the requested data set

min

The minimum value that can be found in the requested data set

ninetyEighthPercentile

Data points with values greater than or equal to this number constitute the “top” 2% of the data set

ninetyFifthPercentile

Data points with values greater than or equal to this number constitute the “top” 5% of the data set

#599 Response Example
HTTP/1.1 200 OK
Access-Control-Allow-Credentials: true
Access-Control-Allow-Methods: POST,GET,OPTIONS,PUT,DELETE
Access-Control-Allow-Origin: *
Content-Encoding: gzip
Content-Type: application/json
Set-Cookie: mojolicious=...; Path=/; Expires=Mon, 18 Nov 2019 17:40:54 GMT; Max-Age=3600; HttpOnly
Whole-Content-Sha512: p4asf1n7fXGtgpW/dWgolJWdXjwDcCjyvjOPFqkckbgoXGUHEj5/wlz7brlQ48t3ZnOWCqOlbsu2eSiBssBtUQ==
X-Server-Name: traffic_ops_golang/
Date: Mon, 28 Oct 2019 20:49:51 GMT

{ "response": {
"series": {
"columns": [
"time",
"sum_count"
],
"count": 4,
"name": "bandwidth.cdn.1min",
"tags": {
"cdn": "CDN-in-a-Box"
},
"values": [
[
1572295500000000000,
null
],
[
1572295560000000000,
113.66666666666666
],
[
1572295620000000000,
108.83333333333334
],
[
1572295680000000000,
113
]
]
},
"summary": {
"average": 111.83333333333333,
"count": 3,
"fifthPercentile": 0,
"max": 113.66666666666666,
"min": 108.83333333333334,
"ninetyEighthPercentile": 113.66666666666666,
"ninetyFifthPercentile": 113.66666666666666
}
}}