finalized write a task content

content/v2.0/process-data/_index.md

@@ -9,7 +9,7 @@ menu:
 ---
 
 InfluxDB's _**task engine**_ is designed for processing and analyzing data.
-Tasks are user defined Flux scripts that take a stream of input data, modify or
+Tasks are user-defined Flux scripts that take a stream of input data, modify or
 analyze it in some way, then perform an action all on a specified schedule.
 Examples include data downsampling, anomaly detection _(Coming)_, alerting _(Coming)_, etc.
 

content/v2.0/process-data/common-tasks/downsample-data.md

@@ -14,3 +14,24 @@ menu:
 - Data source
 - Some type of aggregation
 - and a `to` statement
+
+
+```js
+option task = {
+  name: "cqinterval15m",
+  every: 1w,
+}
+
+data = from(bucket: "telegraf")
+  |> range(start: -task.every * 2)
+  |> filter(fn: (r) => r._measurement == "cpu")
+
+downsampleHourly = (table=<-) =>
+  table
+    |> aggregateWindow(fn: mean, every: 1h)
+    |> set(key: "_measurement", value: "cpu_1h" )
+    |> to(bucket: "telegraf_downsampled")
+
+downsampleHourly(data)
+
+```

content/v2.0/process-data/task-options.md

@@ -0,0 +1,45 @@
+---
+title: Task configuration options
+seotitle: InfluxDB task configuration options
+description: placeholder
+menu:
+  v2_0:
+    name: Task options
+    parent: Process data
+    weight: 5
+---
+
+### name
+I think it might even be optional
+if you dont specify one i think we just put in some default name.
+
+_**Data type:** String_
+
+### every
+Defines the interval at which the task will run.
+
+_**Data type:** Duration_
+
+_Cannot be used with `cron`_
+
+### cron
+- The cron schedule.
+- Based on system time.
+_**Data type:** String_
+
+_Cannot be used with `every`_
+
+### offset
+is so you can allow for data to come in off scheduler. so if you want a task to run on the hour `cron: "0 * * * *"` but your data might come in 10 min late you could say `offset: 15m`
+
+_**Data type:** Duration_
+
+### concurrency
+how many concurrent runs of a task can happen at once.. say your schedule is `every: 1s` but it takes 10 sec to complete. you can set a concurrency that will allow that to happen and not just queue up.
+
+_**Data type:** Integer_
+
+### retry
+The number of times to retry before we assume failure.
+
+_**Data type:** Integer_

content/v2.0/process-data/write-a-task.md

@@ -1,6 +1,6 @@
 ---
-title: Write a task
+title: Write an InfluxDB task
-seotitle: Write a task that processes data in InfluxDB
+seotitle: Write an InfluxDB task that processes data
 description: placeholder
 menu:
   v2_0:
@@ -9,70 +9,133 @@ menu:
     weight: 1
 ---
 
-Tasks are essentially Flux scripts with a "destination."
+InfluxDB tasks are user-defined Flux scripts that take a stream of input data,
-This destination could be
+modify or analyze it in some way, then perform an action all on a specified schedule.
+In their simplest form, tasks are essentially Flux scripts with a "destination."
+This destination could be another bucket, another measurement, an alert endpoint _(Coming)_, etc.
 
+This article walks through writing a basic InfluxDB task that downsamples
+data and stores it in a new bucket.
 
-**Requirements:**
+## Components of a Task
+Every InfluxDB task needs the following four components.
+Their form and order can vary, but the are all essential parts of a task.
 
-- Task options / scheduler block
+- [Task options](#define-task-options)
-- Data source
+- [A data source](#define-a-data-source)
-- Some type of aggregation
+- [Data processing or transformation](#process-or-transform-your-data)
-- and a `to` statement
+- [A destination](#define-a-destination)
+
+_[Skip to the full example task script](#full-example-task-script)_
+
+## Define task options
+Task options define specific information about the task.
+The example below illustrates how task options are defined in your Flux script:
 
 ```js
 option task = {
     name: "cqinterval15m",
     every: 1h,
-    offset: 15m ,
+    offset: 0m,
-    concurrency: 4,
+    concurrency: 1,
     retry: 5
 }
 ```
 
+_See [Task configuration options](/v2.0/process-data/task-options) for detailed information
+about each option._
+
+{{% note %}}
+**When creating a task in the InfluxDB user interface (UI)**, task options are not required
+in your Flux script. They are defined in UI while creating the task.
+{{% /note %}}
+
+## Define a data source
+Define a data source using Flux's [`from()` function](#) or any other [Flux input functions](#).
+
+For convenience, consider creating a variable that includes the sourced data with
+the required `range()` and any relevant filters.
+
 ```js
-option task = {
+data = from(bucket: "telegraf/default")
-    name: "cqinterval15m",
+  |> range(start: -task.every)
-    cron: "0 0 * * *",
+  |> filter(fn: (r) =>
-    offset: 15m ,
+    r._measurement == "mem" AND
-    concurrency: 4,
+    r.host == "myHost"
-    retry: 5
+  )
-}
 ```
 
-## Task configuration options
+{{% note %}}
+#### Using task options in your Flux script
+Task options are passed as part of a `task` object and can be referenced in your Flux script.
+In the example above, the time range is defined as `-task.every`.
 
-### name
+`task.every` is dot notation that references the `every` property of the `task` object.
-I think it might even be optional
+`every` is defined as `1h`, therefore `-task.every` equates to `-1h`.
-if you dont specify one i think we just put in some default name.
 
-_**Data type:** String_
+Using task options to define values in your Flux script can make reusing your task easier.
+{{% /note %}}
 
-### every
+## Process or transform your data
-Defines the inteveral at which the task will run.
+The purpose of tasks is to process or transform data in some way.
+What exactly happens and what form the output data takes is up to you and your
+specific use case.
 
-_**Data type:** Duration_
+The example below illustrates a task that downsamples data by calculating the average of set intervals.
+It uses the `data` variable defined [above](#define-a-data-source) as the data source.
+It then windows the data into 5 minute intervals and calculates the average of each
+window using the [`aggregateWindow()` function](#).
 
-_Cannot be used with `cron`_
+```js
+data
+  |> aggregateWindow(
+    every: 5m,
+    fn: mean
+  )
+```
 
-### cron
+_See [Common tasks](/v2.0/process-data/common-tasks) for examples of tasks commonly used with InfluxDB._
-- The cron schedule.
-- Based on system time.
-_**Data type:** String_
 
-_Cannot be used with `every`_
+## Define a destination
+In the vast majority of task use cases, once data is transformed, it needs to sent and stored somewhere.
+This could be a separate bucket with a different retention policy, another measurement, or even an alert endpoint _(Coming)_.
 
-### offset
+The example below uses Flux's [`to()` function](#) to send the transformed data to another bucket:
-is so you can allow for data to come in off scheduler. so if you want a task to run on the hour `cron: "0 * * * *"` but your data might come in 10 min late you could say `offset: 15m`
 
-_**Data type:** Duration_
+```js
+// ...
+|> to(bucket: "telegraf_downsampled")
+```
 
-### concurrency
+## Full example task script
-how many concurrent runs of a task can happen at once.. say your schedule is `every: 1s` but it takes 10 sec to complete. you can set a concurrency that will allow that to happen and not just queue up.
+Below is the full example task script that combines all of the components described above:
 
-_**Data type:** Integer_
 
-### retry
+```js
-is a int, the number of times to retry before we assume failure.
+// Task options
+option task = {
+    name: "cqinterval15m",
+    every: 1h,
+    offset: 0m,
+    concurrency: 1,
+    retry: 5
+}
 
-_**Data type:** Integer_
+// Data source
+data = from(bucket: "telegraf/default")
+  |> range(start: -task.every)
+  |> filter(fn: (r) =>
+    r._measurement == "mem" AND
+    r.host == "myHost"
+  )
+
+data
+  // Data transformation
+  |> aggregateWindow(
+    every: 5m,
+    fn: mean
+  )
+  // Data destination
+  |> to(bucket: "telegraf_downsampled")
+
+```