Aggregating tasks by duration for each day in a week/month? (PoSH) - powershell

Question

I am parsing JSON from a web service to get my tasks (using a TimeFlip). Right now, I get back each task, when it occurred, and duration, so the data looks like this:
(taskname, start, durationinSec)
TaskA,"6/5/2018 12:16:36 PM",312
TaskB,"6/5/2018 12:30:36 PM",200
TaskA,"6/6/2018 08:00:00 AM",150
TaskA,"6/6/2018 03:00:00 PM",150
(etc etc)
I would like to generate a rollup report, showing by day which tasks had how much time.
While the data will span weeks, I'm just trying to do a weekly report that I can easily transcribe into our time app (since they won't give me an API key). So I'll do something like where {$_.start -gt (? {$_.start -gt (get-date -Hour 0 -Minute 00 -Second 00).adddays(-7)} first.
6/5/2018 6/6/2018
TaskA 312 300
TaskB 200
How can I do that? I assume group-object, but unclear how you'd do either the pivot or even the grouping.

Answer 1

The following doesn't output a pivot table, but performs the desired grouping and aggregation:
$rows = #'
taskname,start,durationinSec
TaskA,"6/5/2018 12:16:36 PM",312
TaskB,"6/5/2018 12:30:36 PM",200
TaskA,"6/6/2018 08:00:00 AM",150
TaskA,"6/6/2018 03:00:00 PM",150
'# | ConvertFrom-Csv
$rows | Group-Object { (-split $_.start)[0] }, taskname | ForEach-Object {
$_ | Select-Object #{ n='Date'; e={$_.Values[0]} },
#{ n='Task'; e={$_.Values[1]} },
#{ n='Duration'; e={ ($_.Group | Measure-Object durationInSec -Sum).Sum } }
}
(-split $_.start)[0] splits each start value by whitespace and returns the first token ([0]), which is the date portion of the time stamp; e.g., 6/5/2018 is returned for 6/5/2018 12:16:36 PM; passing this operation as a script block ({ ... }) to Group-Object means that grouping happens by date only, not also time (in addition to grouping by taskname).
This yields:
Date Task Duration
---- ---- --------
6/5/2018 TaskA 312
6/5/2018 TaskB 200
6/6/2018 TaskA 300
To construct pivot-table-like output requires substantially more effort, and it won't be fast:
Assume that $objs contains the objects created above ($objs = $rows | Group-Object ...).
# Get all distinct dates.
$dates = $objs | Select-Object -Unique -ExpandProperty Date
# Get all distinct tasks.
$tasks = $objs | Select-Object -Unique -ExpandProperty Task
# Create an ordered hashtable that contains an entry for each task that
# holds a nested hashtable with (empty-for-now) entries for all dates.
$ohtPivot = [ordered] #{}
$tasks | ForEach-Object {
$ohtDates = [ordered] #{}
$dates | ForEach-Object { $ohtDates[$_] = $null }
$ohtPivot[$_] = $ohtDates
}
# Fill the hashtable from the grouped objects with the task- and
# date-specific durations.
$objs | ForEach-Object { $ohtPivot[$_.Task][$_.Date] = $_.Duration }
# Output the resulting hashtable in pivot-table-like form by transforming
# each entry into a custom object
$ohtPivot.GetEnumerator() | ForEach-Object {
[pscustomobject] #{ Task = $_.Key } | Add-Member -PassThru -NotePropertyMembers $_.Value
}
The above yields:
Task 6/5/2018 6/6/2018
---- -------- --------
TaskA 312 300
TaskB 200

Answer 2

Googling for PowerShell and Pivot I found this gist.github.com with a more universal way to create the PivotTable.
To transpose (swap x,y) you simply change the variables $rotate, $keep
It has the additional benefit of calculating a row Total
## Q:\Test\2018\06\09\PivotTable.ps1
## Source https://gist.github.com/andyoakley/1651859
# #############################################################################
# Rotates a vertical set similar to an Excel PivotTable
# #############################################################################
$OutputFile = "MyPivot.csv"
$data = #'
taskname,start,duration
TaskA,"6/5/2018 12:16:36 PM",312
TaskB,"6/5/2018 12:30:36 PM",200
TaskA,"6/6/2018 08:00:00 AM",150
TaskA,"6/6/2018 03:00:00 PM",150
'# | ConvertFrom-Csv |Select-Object taskname, duration, #{n='start';e={($_.start -split ' ')[0]}}
# Fields of interest
$rotate = "taskname" # Bits along the top
$keep = "start" # Those along the side
$value = "duration" # What to total
#-------------------- No need to change anything below ------------------------
# Creatre variable to store the output
$rows = #()
# Find the unique "Rotate" [top row of the pivot] values and sort ascending
$pivots = $data | select -unique $rotate | foreach { $_.$rotate} | Sort-Object
# Step through the original data...
# for each of the "Keep" [left hand side] find the Sum of the "Value" for each "Rotate"
$data |
group $keep |
foreach {
$group = $_.Group
# Create the data row and name it as per the "Keep"
$row = new-object psobject
$row | add-member NoteProperty $keep $_.Name
# Cycle through the unique "Rotate" values and get the sum
foreach ($pivot in $pivots) {
$row | add-member NoteProperty $pivot ($group | where { $_.$rotate -eq $pivot } | measure -sum $value).Sum
}
# Add the total to the row
$row | add-member NoteProperty Total ($group | measure -sum $value).Sum
# Add the row to the collection
$rows += $row
}
# Do something with the pivot rows
$rows | Format-Table
$rows | Export-Csv $OutputFile -NoTypeInformation
Sample output:
start TaskA TaskB Total
----- ----- ----- -----
6/5/2018 312 200 512
6/6/2018 300 300
Or x/y swapped
taskname 6/5/2018 6/6/2018 Total
-------- -------- -------- -----
TaskA 312 300 612
TaskB 200 200