{
  "$schema": "http://json-schema.org/draft-04/schema#",
  "title": "Application Health",
  "description": "Schema for media type application/health+json",
  "type": "object",
  "properties": {
    "application": {
      "$ref": "#/definitions/application"
    },
    "health": {
      "$ref": "#/definitions/health"
    },
    "databases": {
      "$ref": "#/definitions/databases"
    },
    "integrationpoints": {
      "$ref": "#/definitions/integrationpoints"
    },
    "circuitbreakers": {
      "$ref": "#/definitions/circuitbreakers"
    },
    "filesystems": {
      "$ref": "#/definitions/filesystems"
    }
  },
  "required": [
    "application",
    "health"
  ],
  "definitions": {
    "application": {
      "title": "Application Information",
      "description": "General information about application and current version",
      "type": "object",
      "properties": {
        "name": {
          "title": "Application name",
          "description": "Organization-wide unique name for identifying the application",
          "type": "string",
          "minLength": 1
        },
        "datetime": {
          "title": "Current date and time",
          "description": "The application's current date and time incl. timezone (in ISO 8601: https://tools.ietf.org/html/rfc3339#section-5.6)",
          "type": "string",
          "format": "date-time",
          "minLength": 1
        },
        "startup": {
          "title": "Startup timestamp",
          "description": "The date and time of when the application instance started (in ISO 8601: https://tools.ietf.org/html/rfc3339#section-5.6)",
          "type": "string",
          "format": "date-time",
          "minLength": 1
        },
        "uptime": {
          "title": "Application uptime",
          "description": "The duration how long the application instance is running in the format: \"2 days, 12:43:22\"",
          "type": "string",
          "pattern": "^\\d+ days, \\d{2}:\\d{2}:\\d{2}(.\\d+)*$",
          "minLength": 1
        },
        "hostname": {
          "title": "Hostname",
          "description": "Name of the host which is running the application instance",
          "type": "string",
          "format": "hostname",
          "minLength": 1
        },
        "version": {
          "title": "Version",
          "description": "Current application version",
          "type": "string",
          "minLength": 1
        }
      },
      "required": [
        "name",
        "datetime",
        "startup",
        "uptime",
        "hostname"
      ]
    },
    "health": {
      "title": "Health status",
      "description": "Global health status aggregated by groups",
      "type": "object",
      "properties": {
        "databases": {
          "type": "boolean"
        },
        "integrationpoints": {
          "type": "boolean"
        },
        "circuitbreakers": {
          "type": "boolean"
        },
        "filesystem": {
          "type": "boolean"
        }
      }
    },
    "database": {
      "title": "Database health",
      "description": "Detailed health information about a connected database",
      "type": "object",
      "properties": {
        "name": {
          "type": "string",
          "description": "Unique name/identifier of the database system",
          "minLength": 1
        },
        "essential": {
          "type": "boolean",
          "description": "Database is essential for overall application health"
        },
        "health": {
          "type": "boolean",
          "description": "Connection established without any limitations"
        },
        "latency": {
          "type": "number",
          "description": "Latency or duration for full roundtrip in milliseconds"
        },
        "connections": {
          "type": "integer",
          "description": "Number of connections established"
        },
        "error": {
          "type": "string",
          "description": "Connectivity error occured, if any"
        }
      },
      "required": [
        "name",
        "essential",
        "health",
        "latency"
      ]
    },
    "integrationpoint": {
      "title": "Integration point health",
      "description": "Detailed health information about an integration point",
      "type": "object",
      "properties": {
        "name": {
          "type": "string",
          "description": "Unique name/identifier of the integraiton point",
          "minLength": 1
        },
        "uri": {
          "type": "string",
          "description": "Base URI of the integration point",
          "minLength": 1
        },
        "essential": {
          "type": "boolean",
          "description": "Integration point is essential for overall application health"
        },
        "health": {
          "type": "boolean",
          "description": "Integration point callable without any limitations"
        },
        "latency": {
          "type": "number",
          "description": "Latency or duration for full roundtrip in milliseconds"
        },
        "lastCall": {
          "type": "string",
          "format": "date-time",
          "description": "Date and time of last call to integration point (in ISO 8601: https://tools.ietf.org/html/rfc3339#section-5.6)",
          "minLength": 1
        },
        "lastSuccess": {
          "type": "string",
          "format": "date-time",
          "description": "Date and time of last successful call to integration point (in ISO 8601: https://tools.ietf.org/html/rfc3339#section-5.6)",
          "minLength": 1
        },
        "callsLastMinute": {
          "type": "integer",
          "description": "Total number of calls to integration point within the last minute"
        },
        "callsLastHour": {
          "type": "integer",
          "description": "Total number of calls to integration point within the last hour"
        },
        "error": {
          "type": "string",
          "description": "Error occured when calling integration point, if any"
        }
      },
      "required": [
        "name",
        "essential",
        "health",
        "latency"
      ]
    },
    "circuitbreaker": {
      "title": "Circuit breaker state",
      "description": "Detailed state information about a circuit breaker",
      "type": "object",
      "properties": {
        "name": {
          "type": "string",
          "description": "Unique name/identifier of the circuit breaker",
          "minLength": 1
        },
        "essential": {
          "type": "boolean",
          "description": "Service behind circuit breaker is essential for overall application health"
        },
        "health": {
          "type": "boolean",
          "description": "True if circuit breaker is closed"
        },
        "state": {
          "type": "string",
          "pattern": "^closed|half-open|open$",
          "description": "Current state of the circuit breaker"
        },
        "timeout": {
          "type": "string",
          "format": "date-time",
          "description": "If state is \"open\", the date and time when the circuit breaker will switch back to half-open (in ISO 8601: https://tools.ietf.org/html/rfc3339#section-5.6)"
        },
        "lastCall": {
          "type": "string",
          "format": "date-time",
          "description": "Date and time of last call through circuit breaker (in ISO 8601: https://tools.ietf.org/html/rfc3339#section-5.6)",
          "minLength": 1
        },
        "lastSuccess": {
          "type": "string",
          "format": "date-time",
          "description": "Date and time of last successful call through circuit breaker (in ISO 8601: https://tools.ietf.org/html/rfc3339#section-5.6)",
          "minLength": 1
        },
        "callsLastMinute": {
          "type": "integer",
          "description": "Total number of calls through circuit breaker within the last minute"
        },
        "callsLastHour": {
          "type": "integer",
          "description": "Total number of calls through circuit breaker within the last hour"
        },
        "error": {
          "type": "string",
          "description": "Error occured when calling circuit breaker, if any"
        }
      },
      "required": [
        "name",
        "essential",
        "health",
        "state"
      ]
    },
    "filesystem": {
      "title": "File system health",
      "description": "Detailed health information about a mounted file system",
      "type": "object",
      "properties": {
        "name": {
          "type": "string",
          "description": "Unique name/identifier of the file system",
          "minLength": 1
        },
        "essential": {
          "type": "boolean",
          "description": "File system access is essential for overall application health"
        },
        "health": {
          "type": "boolean",
          "description": "Filesystem is fully accessible with expected rights"
        },
        "readable": {
          "type": "boolean",
          "description": "Filesystem is readable"
        },
        "writable": {
          "type": "boolean",
          "description": "Filesystem is writable"
        },
        "latency": {
          "type": "number",
          "description": "Latency or duration for full roundtrip in milliseconds"
        },
        "error": {
          "type": "string",
          "description": "Connectivity error occured, if any"
        }
      },
      "required": [
        "name",
        "essential",
        "health",
        "latency"
      ]
    },
    "databases": {
      "title": "Database health",
      "description": "Detailed health information about all connected databases",
      "type": "array",
      "minItems": 1,
      "items": {
        "$ref": "#/definitions/database"
      }
    },
    "integrationpoints": {
      "title": "Integration point health",
      "description": "Detailed health information about all integration points",
      "type": "array",
      "minItems": 1,
      "items": {
        "$ref": "#/definitions/integrationpoint"
      }
    },
    "circuitbreakers": {
      "title": "Circuit breaker health",
      "description": "Detailed health information about all circuit breakers",
      "type": "array",
      "minItems": 1,
      "items": {
        "$ref": "#/definitions/circuitbreaker"
      }
    },
    "filesystems": {
      "title": "File system health",
      "description": "Detailed health information about all mounted file systems",
      "type": "array",
      "minItems": 1,
      "items": {
        "$ref": "#/definitions/filesystem"
      }
    }
  }
}