API Reliability Monitoring and Health Checks with Kestra

id: api-reliability-monitor
namespace: company.team

description: |
  Reusable API reliability monitoring workflow.
  The flow checks an HTTP endpoint, evaluates its response status
  against an expected status code, logs the health result, and
  generates a structured monitoring event for downstream automation.

inputs:
  - id: api_url
    type: STRING
    defaults: https://httpbin.org/status/500
    description: HTTP endpoint to monitor.

  - id: expected_status
    type: INT
    defaults: 200
    description: Expected HTTP response status code.

tasks:
  - id: check_api
    type: io.kestra.plugin.core.http.Request
    uri: "{{ inputs.api_url }}"
    method: GET
    options:
      allowedResponseCodes:
        - 200
        - 500

  - id: evaluate_health
    type: io.kestra.plugin.core.flow.If
    condition: "{{ outputs.check_api.code == inputs.expected_status }}"
    then:
      - id: api_healthy
        type: io.kestra.plugin.core.log.Log
        message: |
          API HEALTH CHECK: HEALTHY

          Endpoint: {{ inputs.api_url }}
          Expected Status: {{ inputs.expected_status }}
          Actual Status: {{ outputs.check_api.code }}

          The API responded with the expected status code.
    else:
      - id: api_unhealthy
        type: io.kestra.plugin.core.log.Log
        message: |
          API HEALTH CHECK: UNHEALTHY

          Endpoint: {{ inputs.api_url }}
          Expected Status: {{ inputs.expected_status }}
          Actual Status: {{ outputs.check_api.code }}

          The API did not return the expected status code.

  - id: health_summary
    type: io.kestra.plugin.core.log.Log
    message: |
      API RELIABILITY MONITORING SUMMARY

      Endpoint: {{ inputs.api_url }}
      Expected Status: {{ inputs.expected_status }}
      Actual Status: {{ outputs.check_api.code }}

      Check completed at: {{ execution.startDate }}

  - id: generate_health_event
    type: io.kestra.plugin.datagen.core.Generate
    generator:
      type: io.kestra.plugin.datagen.generators.JsonObjectGenerator
      value:
        endpoint: "{{ inputs.api_url }}"
        expected_status: "{{ inputs.expected_status }}"
        actual_status: "{{ outputs.check_api.code }}"
        execution_id: "{{ execution.id }}"
        check_time: "{{ execution.startDate }}"

triggers:
  - id: scheduled_check
    type: io.kestra.plugin.core.trigger.Schedule
    cron: "@hourly"
    timezone: Asia/Kolkata

This Blueprint provides a reusable API reliability monitoring workflow that checks an HTTP endpoint on an hourly schedule and evaluates its response against a configurable expected HTTP status code.

Features

Configure the endpoint using the api_url input.
Set the expected HTTP response code using expected_status.
Log whether the endpoint is healthy or unhealthy.
Generate a structured health event containing the endpoint, expected status, actual status, execution ID, and check time.
Run checks automatically every hour.

Prerequisites

A running Kestra instance.
Network access from Kestra to the configured HTTP endpoint.
No secrets are required for the default public HTTP test endpoint.

Quick start

Import this flow into Kestra.
Set api_url to the endpoint you want to monitor.
Set expected_status to the HTTP status code that indicates success.
Execute the flow manually to inspect the health result and generated event.
Enable the hourly schedule for recurring checks.

Expected results

If the response status matches expected_status, the flow logs a healthy result.
If the response status differs, the flow logs an unhealthy result.
The health event includes the endpoint, expected and actual status codes, execution ID, and check time.

Notes

The workflow explicitly allows HTTP 200 and 500 responses so they can be evaluated by the health-check logic. Other HTTP errors may fail the request task unless added to allowedResponseCodes.