6. if

Last updated: Sep 8, 2025

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Definition

In a config modifier schema, use if to define a conditional state to run a given action or not.

Exclusive keywords

If properties, if, concat, switch, pipe, or merge are present at the same nesting level, only the first keyword listed will run. We recommend not listing these keywords together at the same nesting level.

A conditional allows you to determine how to construct an output value by conditionally executing different keywords, based on the evaluation of a set of values.

You can use one of these sub-keywords to construct a conditional statement:

operator
terms
then
else

Nesting level

This keyword executes at the following nesting level:

omit
constant
references
use
get
properties or if or concat or switch or pipe or merge
default
plugin

Sub-keywords

operator

Determines what action to take based on one of the following operators. The config modifier defines what should happen if a value exists and meets the criteria of any of these operators.

Definition of existence

We define existence of a value based on some rules. Specifically, these evaluations are defined as does not exist:

undefined
null
''
[]
NaN

We specifically treat some Falsy (learn about Falsy) values as exists:

false
0
' ' (empty string but padded with a space)

equals

all

some

none

includes

Specifies that the first value in the defined terms contains the second value.

If the second value is included in the first, the then action occurs. If not—or if the first value isn't an array or a single string—the else action occurs.

If a string, value matching is case-sensitive. The second value must be a single primitive value.

Array example

Example: Observations output

json

1
"Observations": [
2
    {
3
      "AbnormalFlag": null,
4
      "Code": "93246-7",
5
      ...
6
      "Status": "Final",
7
      "Units": null,
8
      "Value": "1",
9
      "ValueType": "Coded Entry"
10
    },
11
    {
12
      "AbnormalFlag": null,
13
      "Code": "93247-5",
14
      ...
15
      "Status": "Final",
16
      "Units": null,
17
      "Value": "1",
18
      "ValueType": "Coded Entry"
19
    },
20
    {
21
      "AbnormalFlag": null,
22
      "Code": "93267-3",
23
      ...
24
      "Status": "Final",
25
      "Units": null,
26
      "Value": "1",
27
      "ValueType": "Coded Entry"
28
    },
29
    {
30
      "AbnormalFlag": null,
31
      "Code": "93269-9",
32
      ...
33
      "Status": "Final",
34
      "Units": null,
35
      "Value": "0",
36
      "ValueType": "Coded Entry"
37
    }
38
  ],

Example: Observations selector

json

1
$.Observations

Example: Config modifier with concat and include keywords

yaml

1
items:
2
  if:
3
   operator: includes
4
   terms:
5
      - concat:
6
        - constant: NF1570400504
7
        - constant: NF1570400181
8
        - constant: 93374-7
9
      - get: Code
10
   then:
11
     omit: true
12
   else:
13
     comment: do pass observation through

Based on this example config modifier, the output would be:

Example: Observations output

json

1
"Observations": [
2
    {
3
      "AbnormalFlag": null,
4
      "Code": "93246-7",
5
      ...
6
      "Status": "Final",
7
      "Units": null,
8
      "Value": "1",
9
      "ValueType": "Coded Entry"
10
    },
11
    {
12
      "AbnormalFlag": null,
13
      "Code": "93247-5",
14
      ...
15
      "Status": "Final",
16
      "Units": null,
17
      "Value": "1",
18
      "ValueType": "Coded Entry"
19
    },
20
    {
21
      "AbnormalFlag": null,
22
      "Code": "93267-3",
23
      ...
24
      "Status": "Final",
25
      "Units": null,
26
      "Value": "1",
27
      "ValueType": "Coded Entry"
28
    },
29
    {
30
      "AbnormalFlag": null,
31
      "Code": "93269-9",
32
      ...
33
      "Status": "Final",
34
      "Units": null,
35
      "Value": "0",
36
      "ValueType": "Coded Entry"
37
    }
38
  ],

String example

Example: Includes string input

json

1
{
2
  "partyType": "picnic"
3
}

Example: Config modifier with includes operator for string

yaml

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if:
2
  operator: includes
3
  terms:
4
    - get: partyType
5
    - constant: picnic
6
  then:
7
    constant: Party is a picnic
8
  else:
9
    constant: Party isn't a picnic

Based on this example config modifier, the output would be:

Example: Output string for includes operator

json

1
"Party is a picnic"

terms

Defines a sequential array of keywords to execute on. All terms are evaluated in sequence, then the related operator performs the appropriate action. You can review the requirements for terms based on the operator used.

Refer to a selector

Within the context of a terms keyword statement, you can use {} to retrieve a value at the already defined selector instead of repeating the same path. Learn about referring to a selector.

then / else

These keywords are used in conjunction with each other to define which action should happen when:

Execute the then action when the operator resolves to a true state.
Execute the else action when the operator resolves to a false state.

Example

For example, you could define which fields to use to build an object.

Example: Then / else input from initial payload

json

1
{
2
  "Orders": [
3
    {
4
      "ApplicationOrderID": "844",
5
      "ClinicalInfo": [],
6
      "CollectionDateTime": "2025-05-29T14:59:00.000Z",
7
      "Comments": null,
8
      "Diagnoses": [
9
        {
10
          "Code": "Z13.71",
11
          "Codeset": "ICD-10",
12
          "DocumentedDateTime": null,
13
          "Name": "Encounter for nonprocreative screening for genetic disease carrier status",
14
          "Type": "Unknown"
15
        }
16
      ],
17
      ...
18
      "Procedure": {
19
        "Code": "523",
20
        "Codeset": "GDXEAP",
21
        "Description": "GDX NEURO-NDD"
22
      },
23
      ...
24
      "Status": "Update",
25
      "TransactionDateTime": "2025-05-29T14:59:25.000Z"
26
    }
27
  ],
28
}

Example: Then / else selector

json

1
$.Orders[*].Procedure.Code

Example: Config modifier with then / else keywords

yaml

1
if:
2
  operator: equals
3
  terms:
4
    - {}
5
    - constant: '523'
6
  then:
7
    constant: '691'
8
  else:
9
    comment: pass original value

During processing, the request checks if the procedure code equals 523 in the initial payload. If so, the then action executes, meaning that the procedure code is set to 691. If the procedure code doesn’t equal 523, the else action executes, meaning that the original procedure code is passed.

Example: Then / else output

json

1
"Orders": [
2
    {
3
      "ApplicationOrderID": "844",
4
      "ClinicalInfo": [],
5
      "CollectionDateTime": "2025-05-29T14:59:00.000Z",
6
      "Comments": null,
7
      "Diagnoses": [
8
        {
9
          "Code": "Z13.71",
10
          "Codeset": "ICD-10",
11
          "DocumentedDateTime": null,
12
          "Name": "Encounter for nonprocreative screening for genetic disease carrier status",
13
          "Type": "Unknown"
14
        }
15
      ],
16
      ...
17
      "Procedure": {
18
        "Code": "691",                                                        <--- this is the change here
19
        "Codeset": "GDXEAP",
20
        "Description": "GDX NEURO-NDD"
21
      },
22
      ...
23
      "Status": "Update",
24
      "TransactionDateTime": "2025-05-29T14:59:25.000Z"
25
    }
26
  ],

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