117 lines
5.5 KiB
Markdown
117 lines
5.5 KiB
Markdown
---
|
|
title: Using the HTTP input plugin with Citi Bike data
|
|
description: Collect live metrics on Citi Bike stations in New York City with the HTTP input plugin.
|
|
menu:
|
|
telegraf_1_16:
|
|
name: Using the HTTP plugin
|
|
weight: 30
|
|
parent: Guides
|
|
---
|
|
|
|
This example walks through using the Telegraf HTTP input plugin to collect live metrics on Citi Bike stations in New York City. Live station data is available in JSON format from [NYC OpenData](https://data.cityofnewyork.us/NYC-BigApps/Citi-Bike-Live-Station-Feed-JSON-/p94q-8hxh).
|
|
|
|
For the following example to work, configure [`influxdb` output plugin](/telegraf/v1.15/plugins/#output-influxdb). This plugin is what allows Telegraf to write the metrics to your InfluxDB.
|
|
|
|
## Configure the HTTP Input plugin in your Telegraf configuration file
|
|
|
|
To retrieve data from the Citi Bike URL endpoint, enable the `inputs.http` input plugin in your Telegraf configuration file.
|
|
|
|
Specify the following options:
|
|
|
|
### `urls`
|
|
One or more URLs to read metrics from. For this example, use `https://feeds.citibikenyc.com/stations/stations.json`.
|
|
|
|
### `data_format`
|
|
The format of the data in the HTTP endpoints that Telegraf will ingest. For this example, use JSON.
|
|
|
|
|
|
## Add parser information to your Telegraf configuration
|
|
|
|
Specify the following JSON-specific options.
|
|
|
|
### JSON
|
|
|
|
#### `json_query`
|
|
To parse only the relevant portion of JSON data, set the `json_query` option with a [GJSON](https://github.com/tidwall/gjson) path. The result of the query should contain a JSON object or an array of objects.
|
|
In this case, we don't want to parse the JSON query's `executionTime` at the beginning of the data, so we'll limit this to include only the data in the `stationBeanList` array.
|
|
|
|
#### `tag_keys`
|
|
List of one or more JSON keys that should be added as tags. For this example, we'll use the tag keys `id`, `stationName`, `city`, and `postalCode`.
|
|
|
|
#### `json_string_fields`
|
|
List the keys of fields that are in string format so that they can be parsed as strings. Here, the string fields are `statusValue`, `stAddress1`, `stAddress2`, `location`, and `landMark`.
|
|
|
|
#### `json_time_key`
|
|
Key from the JSON file that creates the timestamp metric. In this case, we want to use the time that station data was last reported, or the `lastCommunicationTime`. If you don't specify a key, the time that Telegraf reads the data becomes the timestamp.
|
|
|
|
#### `json_time_format`
|
|
The format used to interpret the designated `json_time_key`. This example uses [Go reference time format](https://golang.org/pkg/time/#Time.Format). For example, `Mon Jan 2 15:04:05 MST 2006`.
|
|
|
|
#### `json_timezone`
|
|
The timezone We'll set this to the Unix TZ value where our bike data takes place, `America/New_York`.
|
|
|
|
|
|
#### Example configuration
|
|
|
|
```toml
|
|
[[inputs.http]]
|
|
#URL for NYC's Citi Bike station data in JSON format
|
|
urls = ["https://feeds.citibikenyc.com/stations/stations.json"]
|
|
|
|
#Overwrite measurement name from default `http` to `citibikenyc`
|
|
name_override = "citibikenyc"
|
|
|
|
#Exclude url and host items from tags
|
|
tagexclude = ["url", "host"]
|
|
|
|
#Data from HTTP in JSON format
|
|
data_format = "json"
|
|
|
|
#Parse `stationBeanList` array only
|
|
json_query = "stationBeanList"
|
|
|
|
#Set station metadata as tags
|
|
tag_keys = ["id", "stationName", "city", "postalCode"]
|
|
|
|
#Do not include station landmark data as fields
|
|
fielddrop = ["landMark"]
|
|
|
|
#JSON values to set as string fields
|
|
json_string_fields = ["statusValue", "stAddress1", "stAddress2", "location", "landMark"]
|
|
|
|
#Latest station information reported at `lastCommunicationTime`
|
|
json_time_key = "lastCommunicationTime"
|
|
|
|
#Time is reported in Golang "reference time" format
|
|
json_time_format = "2006-01-02 03:04:05 PM"
|
|
|
|
#Time is reported in Eastern Standard Time (EST)
|
|
json_timezone = "America/New_York"
|
|
```
|
|
|
|
|
|
|
|
## Start Telegraf and verify data appears
|
|
|
|
[Start the Telegraf service](/telegraf/v1.15/introduction/getting-started/#start-telegraf-service).
|
|
|
|
To test that the data is being sent to InfluxDB, run the following (replacing `telegraf.conf` with the path to your configuration file):
|
|
|
|
```
|
|
telegraf -config ~/telegraf.conf -test
|
|
```
|
|
|
|
This command should return line protocol that looks similar to the following:
|
|
|
|
|
|
```
|
|
citibikenyc,id=3443,stationName=W\ 52\ St\ &\ 6\ Ave statusKey=1,location="",totalDocks=41,availableDocks=32,latitude=40.76132983124814,longitude=-73.97982001304626,availableBikes=8,stAddress2="",stAddress1="W 52 St & 6 Ave",statusValue="In Service" 1581533519000000000
|
|
citibikenyc,id=367,stationName=E\ 53\ St\ &\ Lexington\ Ave availableBikes=8,stAddress1="E 53 St & Lexington Ave",longitude=-73.97069431,latitude=40.75828065,stAddress2="",statusKey=1,location="",statusValue="In Service",totalDocks=34,availableDocks=24 1581533492000000000
|
|
citibikenyc,id=359,stationName=E\ 47\ St\ &\ Park\ Ave totalDocks=64,availableBikes=15,statusValue="In Service",location="",latitude=40.75510267,availableDocks=49,stAddress1="E 47 St & Park Ave",longitude=-73.97498696,statusKey=1,stAddress2="" 1581533535000000000
|
|
citibikenyc,id=304,stationName=Broadway\ &\ Battery\ Pl statusValue="In Service",availableDocks=11,stAddress1="Broadway & Battery Pl",statusKey=1,stAddress2="",location="",totalDocks=33,latitude=40.70463334,longitude=-74.01361706,availableBikes=22 1581533499000000000
|
|
```
|
|
|
|
Now, you can explore and query the Citi Bike data in InfluxDB. The example below is an InfluxQL query and visualization showing the number of available bikes over the past 15 minutes at the Broadway and West 29th Street station.
|
|
|
|
|