When developers like Mike! start their sentence with “this is probably really simple”, you know that it rarely is. (No idea why he’s so excited about his name though, I suspect there is some math flex in here).

This is probably really simple, but anyone know how I would add an index to an array of objects in flow e.g. (– thank you Tîpp Jäår, for nice formatting; -you’re welcome, Mike! – t.j.).

Initial Array (returned from a connector):
[
   {“Name”: “Foo”},
   {“Name”: “Bar”}
]

Output Array:
[
   {“Order”: 1, “Name”: “Foo”},
   {“Order”: 2, “Name”: “Bar”}
]

Mike!!!

Honestly, I was waiting for Linn to produce some json > xml > xpath > json magic but the best he could come up with was, and I quote, “🤣 “(true story). Lo and behold as Damien Bird flexes some Scottish voodoo.

Hey Mike (! – t.j.), you can use a select.  Create a range from 1 to length of the array, then simply add the new key into the array as follows:

If we ignore the first step that simply defines the input array, the solution is a one-step magic of Select action with the following parameters:

• From: range(1, length(outputs(‘Compose’)))
  (that creates an array- remember the looping exercise? – t.j.)
• Map > Order: item()
  (array index! – t.j.)
• Map > Order: outputs(‘Compose’)?[item()]?[‘Name’]
  (just repeating the property value – t.j.)

The output as expected:

[
   {“Order”: 0, “Name”: “Foo”},
   {“Order”: 1, “Name”: “Bar”}
]

Yes, it is zero-based and Damien has apologized for that and said that “You can still start your index from 1 with sum(item(),1)“. After this unwarranted and unreserved apology I now suspect Damien is actually a Canadian and not a Scot.

Cover image is by Gerd Altmann