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Writing expressions using any JSON parser tool

To provide you with the best experience when using expressions, Harness has introduced support for writing expressions by using any JSON parser tool. With this enhancement, Harness effectively addresses customer concerns and provides a more user-friendly and adaptable expression engine. These improvements enhance the overall user experience, increase productivity, and empower you to have greater control and customization capabilities in your evaluation processes.

The key enhancements are as follows:

  • Enhanced expression discovery: You have the ability to independently determine the expressions associated with a specific step. This empowers you to explore and understand the system better, and thereby reduce reliance on external support.
  • Comprehensive execution JSON: You can access the execution JSON for all stages or individual steps. This JSON contains detailed information about inputs and outputs for each step within the stage. This lets you analyze and troubleshoot workflows effectively and extract the required information easily.
  • Flexible JSON parsing: You can utilize any JSON parsing tool of your choice. This gives you the freedom to parse the execution JSON based on your preferred methods and extract the necessary information as per your requirements.
  • JEXL script support: This enhancement enables you to leverage the full power and flexibility of JEXL expressions, overcoming the limitations of the previous framework. You can now write complex expressions and customize the evaluation process to meet specific needs.

Limitations​

If your step inputs or parameters size is greater than 4 KB, then it cannot be part of your expanded JSON. This is to safeguard your system.

Obtaining the execution JSON​

You can now obtain an execution JSON for all stages or individual steps of your pipeline.

To access the JSON, you must enable the Enable JSON Support for expressions setting first. Go to Account Settings > Account Resources > Pipeline > Enable JSON Support for expressions, and then set the value to true.

This setting is turned off by default. Enabling this setting allows you to reference JSON parsers within expressions.

When you create a pipeline, in the execution section, add a Shell Script step to obtain the execution JSON.

Here's a script that echos the JSON using different built-in expressions for a stage with the Id Custom:

echo "<+pipeline>: "<+pipeline>

echo "<+pipeline.stages.Custom>: "<+pipeline.stages.Custom>

echo "<+pipeline.stages.Custom.spec.execution>: "<+pipeline.stages.Custom.spec.execution>

Here's how you format the output from one of these expressions as JSON:

echo "json.format: " <+json.format(<+pipeline.stages.Custom>)>

Here's the example's output from the executed step's Input tab:

"json.format: " {"stepInputs":{"identifier":"Custom","name":"Custom","description":"","variables":{},"tags":{},"type":"Custom","specConfig":{"childNodeID":"6OI2ed5ZQG2bZsPG90Zzwg"}},"status":"RUNNING","spec":{"stepInputs":{"childNodeId":"EIXj-rTPTa2j_un35s5kRQ","logMessage":"Spec Element"},"status":"RUNNING","execution":{"stepInputs":{"childNodeId":"EIXj-rTPTa2j_un35s5kRQsteps","logMessage":"Execution Element"},"status":"RUNNING","steps":{"stepInputs":{"childNodeId":"lN38FF6sQl-tbOw9yf_vEw","logMessage":"Steps Element"},"status":"RUNNING","ShellScript_1":{"status":"SUCCEEDED","outcome":{"output":{"outputVariables":{}}}},"json_format":{"stepInputs":{"identifier":"json_format","name":"json format","timeout":"10m","type":"ShellScript","spec":{"outputVariables":{},"environmentVariables":{},"secretOutputVariables":[],"shell":"Bash","source":{"type":"Inline","spec":{"script":"echo \"json.format: \" {\"stepInputs\":{\"identifier\":\"Custom\",\"name\":\"Custom\",\"description\":\"\",\"variables\":{},\"tags\":{},\"type\":\"Custom\",\"specConfig\":{\"childNodeID\":\"6OI2ed5ZQG2bZsPG90Zzwg\"}},\"status\":\"RUNNING\",\"spec\":{\"stepInputs\":{\"childNodeId\":\"EIXj-rTPTa2j_un35s5kRQ\",\"logMessage\":\"Spec Element\"},\"status\":\"RUNNING\",\"execution\":{\"stepInputs\":{\"childNodeId\":\"EIXj-rTPTa2j_un35s5kRQsteps\",\"logMessage\":\"Execution Element\"},\"status\":\"RUNNING\",\"steps\":{\"stepInputs\":{\"childNodeId\":\"lN38FF6sQl-tbOw9yf_vEw\",\"logMessage\":\"Steps Element\"},\"status\":\"RUNNING\",\"ShellScript_1\":{\"status\":\"SUCCEEDED\",\"outcome\":{\"output\":{\"outputVariables\":{}}}}}}}}"}},"onDelegate":true},"rollbackParameters":{"strategy":"UNKNOWN","strategyToUuid":{"STAGE_ROLLBACK":"Be2PfjljSjiK3DcfWX2lTg_combinedRollback"},"applicableFailureTypes":[]}}}}}}}
note

When you output the expression in the Shell Script step, the formatting is not strict JSON. Instead, copy the resolved expression from the step's Input tab in a pipeline execution. This will give you valid JSON.

For example, consider a pipeline with two stages. In the second stage, add a Shell Script step to obtain the JSON format of first stage:

echo <+json.format(<+pipeline.stages.stage1>)>

In the pipeline execution page, select the Input section of the Shell Script step in the second stage, and then copy the JSON.

Write expressions using JSON​

You can retrieve specific chunks of data from the following sample execution JSON by locating the corresponding path. For example, to access the status of a combination within the cStage1 matrix, you could use the expression pipeline.stages.cStage.cStage_0.status.

Sample execution JSON
{
  "pipeline": {
    "stepInputs": {
      "childNodeID": "ODlBvLAiTF-p_DNVK-27VAstages",
      "name": "JsonSupportExample1",
      "identifier": "JsonSupportExample1",
      "description": "Pipeline to fetch the current status of all stages under matrix.",
      "tags": {},
      "properties": {},
      "variables": {},
      "executionId": "JRdcH8oBTlKwL1CBZOg0PA"
    },
    "status": "SUCCEEDED",
    "stages": {
      "stepInputs": {
        "childNodeId": "yuWDK3OTTOqBr_nsTN4LKQ",
        "logMessage": "Stages"
      },
      "status": "SUCCEEDED",
      "cStage": {
        "stepInputs": {
          "strategyConfig": {
            "matrixConfig": {
              "uuid": "j79RNzfpTBaiRaPrDFN7TQ",
              "axes": {
                "name": {
                  "axisValue": [
                    "john",
                    "doe",
                    "nick"
                  ]
                }
              },
              "expressionAxes": {}
            }
          },
          "childNodeId": "qPnRHHd8TtOwiK400WBNvw",
          "strategyType": "MATRIX",
          "shouldProceedIfFailed": true
        },
        "status": "SUCCEEDED",
        "cStage_0": {
          "identifierPostFix": {
            "value": {},
            "coder": 0,
            "hash": 0
          },
          "iteration": "0",
          "iterations": "3",
          "matrix": {
            "name": "john"
          },
          "repeat": {},
          "stepInputs": {
            "identifier": "cStage_0",
            "name": "cStage_0",
            "description": "",
            "when": {
              "pipelineStatus": "ALL"
            },
            "variables": {},
            "tags": {},
            "type": "Custom",
            "specConfig": {
              "childNodeID": "i6MmJOUeSJi8j_ZmHeZ9YQ"
            }
          },
          "totalIterations": "3",
          "status": "SUCCEEDED",
          "spec": {
            "stepInputs": {
              "childNodeId": "E8ApHWgQQQ-z7Ua3d0Bc6A",
              "logMessage": "Spec Element"
            },
            "status": "SUCCEEDED",
            "execution": {
              "stepInputs": {
                "childNodeId": "E8ApHWgQQQ-z7Ua3d0Bc6Asteps",
                "logMessage": "Execution Element"
              },
              "status": "SUCCEEDED",
              "steps": {
                "stepInputs": {
                  "childNodeId": "MrayhGS3RhiAWtPHaIG5vg",
                  "logMessage": "Steps Element"
                },
                "status": "SUCCEEDED",
                "ShellScript_1": {
                  "stepInputs": {
                    "identifier": "ShellScript_1",
                    "name": "ShellScript_1",
                    "timeout": "10m",
                    "type": "ShellScript",
                    "spec": {
                      "outputVariables": {},
                      "environmentVariables": {},
                      "secretOutputVariables": [],
                      "shell": "Bash",
                      "source": {
                        "type": "Inline",
                        "spec": {
                          "script": "echo \"My number is: 0\""
                        }
                      },
                      "onDelegate": true
                    },
                    "rollbackParameters": {
                      "strategy": "UNKNOWN",
                      "strategyToUuid": {
                        "STAGE_ROLLBACK": "yuWDK3OTTOqBr_nsTN4LKQ_combinedRollback"
                      },
                      "applicableFailureTypes": []
                    }
                  },
                  "status": "SUCCEEDED",
                  "outcome": {
                    "output": {
                      "outputVariables": {}
                    }
                  }
                }
              }
            }
          }
        },
        "cStage_2": {
          "identifierPostFix": {
            "value": {},
            "coder": 0,
            "hash": 0
          },
          "iteration": "2",
          "iterations": "3",
          "matrix": {
            "name": "nick"
          },
          "repeat": {},
          "stepInputs": {
            "identifier": "cStage_2",
            "name": "cStage_2",
            "description": "",
            "when": {
              "pipelineStatus": "ALL"
            },
            "variables": {},
            "tags": {},
            "type": "Custom",
            "specConfig": {
              "childNodeID": "i6MmJOUeSJi8j_ZmHeZ9YQ"
            }
          },
          "totalIterations": "3",
          "status": "SUCCEEDED",
          "spec": {
            "stepInputs": {
              "childNodeId": "E8ApHWgQQQ-z7Ua3d0Bc6A",
              "logMessage": "Spec Element"
            },
            "status": "SUCCEEDED",
            "execution": {
              "stepInputs": {
                "childNodeId": "E8ApHWgQQQ-z7Ua3d0Bc6Asteps",
                "logMessage": "Execution Element"
              },
              "status": "SUCCEEDED",
              "steps": {
                "stepInputs": {
                  "childNodeId": "MrayhGS3RhiAWtPHaIG5vg",
                  "logMessage": "Steps Element"
                },
                "status": "SUCCEEDED",
                "ShellScript_1": {
                  "stepInputs": {
                    "identifier": "ShellScript_1",
                    "name": "ShellScript_1",
                    "timeout": "10m",
                    "type": "ShellScript",
                    "spec": {
                      "outputVariables": {},
                      "environmentVariables": {},
                      "secretOutputVariables": [],
                      "shell": "Bash",
                      "source": {
                        "type": "Inline",
                        "spec": {
                          "script": "echo \"My number is: 2\""
                        }
                      },
                      "onDelegate": true
                    },
                    "rollbackParameters": {
                      "strategy": "UNKNOWN",
                      "strategyToUuid": {
                        "STAGE_ROLLBACK": "yuWDK3OTTOqBr_nsTN4LKQ_combinedRollback"
                      },
                      "applicableFailureTypes": []
                    }
                  },
                  "status": "SUCCEEDED",
                  "outcome": {
                    "output": {
                      "outputVariables": {}
                    }
                  }
                }
              }
            }
          }
        },
        "cStage_1": {
          "identifierPostFix": {
            "value": {},
            "coder": 0,
            "hash": 0
          },
          "iteration": "1",
          "iterations": "3",
          "matrix": {
            "name": "doe"
          },
          "repeat": {},
          "stepInputs": {
            "identifier": "cStage_1",
            "name": "cStage_1",
            "description": "",
            "when": {
              "pipelineStatus": "ALL"
            },
            "variables": {},
            "tags": {},
            "type": "Custom",
            "specConfig": {
              "childNodeID": "i6MmJOUeSJi8j_ZmHeZ9YQ"
            }
          },
          "totalIterations": "3",
          "status": "SUCCEEDED",
          "spec": {
            "stepInputs": {
              "childNodeId": "E8ApHWgQQQ-z7Ua3d0Bc6A",
              "logMessage": "Spec Element"
            },
            "status": "SUCCEEDED",
            "execution": {
              "stepInputs": {
                "childNodeId": "E8ApHWgQQQ-z7Ua3d0Bc6Asteps",
                "logMessage": "Execution Element"
              },
              "status": "SUCCEEDED",
              "steps": {
                "stepInputs": {
                  "childNodeId": "MrayhGS3RhiAWtPHaIG5vg",
                  "logMessage": "Steps Element"
                },
                "status": "SUCCEEDED",
                "ShellScript_1": {
                  "stepInputs": {
                    "identifier": "ShellScript_1",
                    "name": "ShellScript_1",
                    "timeout": "10m",
                    "type": "ShellScript",
                    "spec": {
                      "outputVariables": {},
                      "environmentVariables": {},
                      "secretOutputVariables": [],
                      "shell": "Bash",
                      "source": {
                        "type": "Inline",
                        "spec": {
                          "script": "echo \"My number is: 1\""
                        }
                      },
                      "onDelegate": true
                    },
                    "rollbackParameters": {
                      "strategy": "UNKNOWN",
                      "strategyToUuid": {
                        "STAGE_ROLLBACK": "yuWDK3OTTOqBr_nsTN4LKQ_combinedRollback"
                      },
                      "applicableFailureTypes": []
                    }
                  },
                  "status": "SUCCEEDED",
                  "outcome": {
                    "output": {
                      "outputVariables": {}
                    }
                  }
                }
              }
            }
          }
        }
      },
      "fetchStatusOfPreviousStage": {
        "stepInputs": {
          "identifier": "fetchStatusOfPreviousStage",
          "name": "fetchStatusOfPreviousStage",
          "description": "",
          "variables": {},
          "tags": {},
          "type": "Custom",
          "specConfig": {
            "childNodeID": "D1eqrqccQHK6YBlqiS51Gw"
          }
        },
        "status": "SUCCEEDED",
        "spec": {
          "stepInputs": {
            "childNodeId": "onyg3VaMTj-X6LmB0m4zIg",
            "logMessage": "Spec Element"
          },
          "status": "SUCCEEDED",
          "execution": {
            "stepInputs": {
              "childNodeId": "onyg3VaMTj-X6LmB0m4zIgsteps",
              "logMessage": "Execution Element"
            },
            "status": "SUCCEEDED",
            "steps": {
              "stepInputs": {
                "childNodeId": "g0fF-nfVRGWD7rmVH-RJEg",
                "logMessage": "Steps Element"
              },
              "status": "SUCCEEDED",
              "ShellScript_1": {
                "stepInputs": {
                  "identifier": "ShellScript_1",
                  "name": "ShellScript_1",
                  "timeout": "10m",
                  "type": "ShellScript",
                  "spec": {
                    "outputVariables": {},
                    "environmentVariables": {},
                    "secretOutputVariables": [],
                    "shell": "Bash",
                    "source": {
                      "type": "Inline",
                      "spec": {
                        "script": "t=\"[]\"\necho $t"
                      }
                    },
                    "onDelegate": true
                  },
                  "rollbackParameters": {
                    "strategy": "UNKNOWN",
                    "strategyToUuid": {
                      "STAGE_ROLLBACK": "A31KTBUdTja1KanfnDrtGQ_combinedRollback"
                    },
                    "applicableFailureTypes": []
                  }
                },
                "status": "SUCCEEDED",
                "outcome": {
                  "output": {
                    "outputVariables": {}
                  }
                }
              }
            }
          }
        }
      }
    }
  }
}

You can determine the complete expression for any desired data by traversing the JSON.

Keep in mind the following considerations when constructing these expressions. These guidelines help you to easily construct expressions that fetch your desired JSON data without using complex or lengthy paths.

  • The full path, starting from pipeline, always works as a reference point.
  • You can ignore fields like stepInputs and outcome when constructing the full path.
  • You can use relative paths. To do this:
    • First, identify the common parent between the step/stage you're referring to and the step/stage where you're making the reference.
    • Then, begin the expression from the common parent. For example, in pipeline.stages.cStage.cStage_0.status, you can refer to the status of CStage_0 from within CStage_1 by using the expression cStage.cStage_0.status.
    • By using a relative path, you don't need to constructing the full path each time.

Write complex expressions using JQ​

JQ is a lightweight, powerful command-line tool specifically designed for JSON processing in Bash. It provides a wide range of features for querying, filtering, and transforming JSON data. JQ can be easily integrated into Bash scripts and can be used to extract specific values or perform complex JSON operations.

To use JQ:

  • With container steps, your images must support JQ.

  • Your Harness Delegate must support JQ if your pipeline has a Shell Script step. For more information, go to How to install JQ on Ubuntu.

    Install JQ on Harness Delegate

    1. Open the delegate.yaml in a text editor.

    2. Locate the environment variable INIT_SCRIPT in the Deployment object.

      - name: INIT_SCRIPT
      value: ""

    3. Replace value: "" with the following script to install JQ.

      - name: INIT_SCRIPT
      value: |
       apt install software-properties-common -y
       apt install python-software-properties -y
       add-apt-repository ppa:rmescandon/yq
       apt update
       apt install yq -y
       apt-get install jq -y

Some JQ use cases are demonstrated in the following sections. These examples use the following sample pipeline.

Sample pipeline YAML
pipeline:
  name: JsonSupportExample1
  identifier: JsonSupportExample1
  projectIdentifier: DoNotDelete_Sahil
  orgIdentifier: default
  description: Pipeline to fetch the current status of all stages under matrix.
  tags: {}
  stages:
  - stage:
        name: stepWithMatrix
        identifier: stepWithMatrix
        description: ""
        type: Custom
        spec:
          execution:
            steps:
              - step:
                  type: ShellScript
                  name: ShellScript_1
                  identifier: ShellScript_1
                  timeout: 10m
                  spec:
                    shell: Bash
                    onDelegate: true
                    source:
                      type: Inline
                      spec:
                        script: |
                          echo "My number is: <+strategy.iteration>"
                    environmentVariables: []
                    outputVariables: []
                  strategy:
                    matrix:
                      name:
                        - john
                        - doe
                        - nick
        tags: {}
        when:
          pipelineStatus: All
    - stage:
        name: stageWithMatrix
        identifier: stageWithMatrix
        description: ""
        type: Custom
        spec:
          execution:
            steps:
              - step:
                  type: ShellScript
                  name: ShellScript_1
                  identifier: ShellScript_1
                  timeout: 10m
                  spec:
                    shell: Bash
                    onDelegate: true
                    source:
                      type: Inline
                      spec:
                        script: |
                          echo "My number is: <+strategy.iteration>"
                    environmentVariables: []
                    outputVariables: []
        tags: {}
        when:
          pipelineStatus: All
        strategy:
          matrix:
            name:
              - john
              - doe
              - nick
        tags: {}

Fetch the status of all combinations of a stage named stageWithMatrix​

Use the following expression to fetch the status of all combinations of a stage named stageWithMatrix:

t='<+json.format(<+pipeline.stages.stageWithMatrix>)>'
echo $t | jq '(. | to_entries[] | select(.key | startswith("stageWithMatrix")) |  .value.status)'

Fetch the status of all identifiers of a step in a stage named stageWithMatrix​

Use the following expression to fetch the status of all identifiers of a step in a stage named stageWithMatrix:

t='<+json.format(<+pipeline.stages.stageWithMatrix>)>'
echo $t | jq '(. | to_entries[] | select(.key | startswith("stageWithMatrix")) | .value.spec.execution.steps | keys[] |  select(.| IN("status", "stepInputs")| not))'

Fetch the status of all combinations of a step named ShellScript_1​

Use the following expression to fetch the status of all combinations of a step named ShellScript_1:

t='<+json.format(<+pipeline.stages.stepWithMatrix.spec.execution.steps.ShellScript_1>)>'
echo $t | jq '(. | to_entries[] | select(.key | startswith("ShellScript_1")) | .value.status)'

Write complex expressions using JEXL​

With script support, Harness enables you to define functions, utilize loops, and incorporate if conditions in your expressions. This expanded functionality empowers your expressions to handle more complex logic and perform advanced operations.

Fetch the status of all combinations of a stage named stageWithMatrix​

The following example expression contains a script.

<+ var traverse = function(key) {
                      var stages = [...];
                      for(stage: key.entrySet())
                      {
                          if (stage.key.startsWith('stageWithMatrix'))
                              stages.add(stage.value);
                      }
                      var statuses=[...];
                      for(stage1:stages) {
                         statuses.add(stage1.status)
                      }
                      statuses
                      };

  traverse(<+pipeline.stages.stageWithMatrix>)>

This script defines a traverse function that takes a parameter called key. Within the function, there are several operations performed:

  • Initialization: The stages array is created, which holds the extracted stages. It is initially empty.
  • Loop: The script loops through each entry in the key object using the for(stage: key.entrySet()) syntax. This loop iterates over each key-value pair in the key object.
  • Condition: Within the loop, there is an IF condition, if (stage.key.startsWith('stageWithMatrix')). It checks if the key of the current stage starts with the string stageWithMatrix.
  • Stage extraction: If the condition is TRUE, the current stage value is added to the stages array using stages.add(stage.value).
  • Status extraction: After extracting the relevant stages, a new array called statuses is created.
  • Nested loop: The script loops through each stage in the stages array using the for(stage1:stages) syntax.
  • Status addition: Within the nested loop, the spec.execution.status value of each stage is extracted and added to the statuses array using statuses.add(stage1.status).
  • Return: Finally, the function returns the statuses array.

The script concludes by invoking the traverse function with the argument, <+pipeline.stages.cStage>. This argument represents the starting point for the traversal, where the pipeline.stages.cStage object is passed as the key.

This script performs a traversal and extraction operation on a data structure represented by the key parameter. It extracts stages that start with stageWithMatrix and collects their corresponding .status values into the statuses array.

Fetch the status of all combinations of a step named ShellScript_1​

The following example expression contains a script.

<+ var traverse = function(key) {
                      var stages = [...];
                      for(stage: key.entrySet())
                      {
                          if (stage.key.startsWith('ShellScript_1'))
                              stages.add(stage.value);
                      }
                      var statuses=[...];
                      for(stage1:stages) {
                         statuses.add(stage1.status)
                      }
                      statuses
                      };

  traverse(<+pipeline.stages.stepWithMatrix.spec.execution.steps.ShellScript_1>)>

This script defines a traverse function that takes a parameter called key. Within the function, there are several operations performed:

  • Initialization: The stages array is created, which holds the extracted stages. It is initially empty.
  • Loop: The script loops through each entry in the key object using the for(stage: key.entrySet()) syntax. This loop iterates over each key-value pair in the key object.
  • Condition: Within the loop, there is an IF condition, if (stage.key.startsWith('stageWithMatrix')). It checks if the key of the current stage starts with the string stageWithMatrix.
  • Stage extraction: If the condition is TRUE, the current stage value is added to the stages array using stages.add(stage.value).
  • Status extraction: After extracting the relevant stages, a new array called statuses is created.
  • Nested loop: The script loops through each stage in the stages array using the for(stage1:stages) syntax.
  • Status addition: Within the nested loop, the spec.execution.status value of each stage is extracted and added to the statuses array using statuses.add(stage1.status).
  • Return: Finally, the function returns the statuses array.

The script concludes by invoking the traverse function with the argument, <+pipeline.stages.stepWithMatrix.spec.execution.steps.ShellScript_1>. This argument represents the starting point for the traversal, where the specific stage (ShellScript_1) within the given pipeline structure is passed as the key.

This script performs a traversal and extraction operation on a data structure represented by the key parameter. It filters stages that start with the string ShellScript_1 and collects their corresponding status values into the statuses array.

Define functions​

Use the function keyword in JEXL to define functions. For example, the following expression contains a JEXL script that defines a function called identityFunction that takes a parameter key. Inside the function, the expression returns the value of the key parameter.

<+
var numbers = [1, 2, 3, 4, 5];
var sum = 0;

for (var i = 0; i < numbers.length; i++) {
  sum = sum + numbers[i];
}

sum;
>

The identityFunction retrieves the value of a specific key. In the given example, the function is invoked with the argument keyName. As a result, the function returns the value keyName itself. The identityFunction serves as a straightforward identity function where the input value is directly returned as the output.

Define loops​

The following example demonstrates how you can use a loop in JEXL to iterate over an array or perform repetitive operations based on certain conditions. This example uses an array called numbers containing several integer values. A variable called sum to 0 is initialized. The for loop iterates over each element in the number array. Within the loop, you can add each element to the sum variable after the loop completes. The script outputs the value of sum (the sum of all the numbers in the array).

<+
var numbers = [1, 2, 3, 4, 5];
var sum = 0;

for (var i = 0; i < numbers.length; i++) {
  sum = sum + numbers[i];
}

sum;
>

Use if conditions​

The following example demonstrates how you can use an if condition in JEXL to perform different actions or display different results based on certain conditions or criteria. This example uses a variable called age with the value 18. The if condition checks if the age is greater than or equal to 18. If the condition evaluates to true, then the script outputs the string You are an adult. Otherwise, it outputs the string You are not yet an adult.

<+var age = 18;

if (age >= 18) {
  "You are an adult";
} else {
  "You are not yet an adult";
}
>