alert.jsonld

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://openamber.eu/schemas/alert.json",
  "title": "OpenAmber Missing Child Alert",
  "description":  "Schema for cryptographically signed missing child alerts",
  "type": "object",
  "required": [
    "@context",
    "type",
    "id",
    "issuer",
    "subject",
    "created",
    "expires",
    "signature"
  ],
  "properties":  {
    "@context": {
      "type": "array",
      "items": {
        "type": "string"
      },
      "contains": {
        "const": "https://openamber.eu/ns/v1"
      },
      "description": "JSON-LD context, must include OpenAmber namespace"
    },
    "type": {
      "const": "MissingChildAlert",
      "description": "Alert type identifier"
    },
    "id": {
      "type": "string",
      "format": "uri",
      "pattern": "^urn:openamber:alert:[A-Z]{2}-[0-9]{4}-[0-9]{5,}$",
      "description": "Unique identifier in format urn:openamber:alert:{country}-{year}-{sequence}"
    },
    "issuer": {
      "$ref": "#/$defs/issuerReference",
      "description": "Organization that created and signed the alert"
    },
    "subject": {
      "$ref": "#/$defs/subjectDescription",
      "description": "Information about the missing child"
    },
    "created": {
      "type": "string",
      "format": "date-time",
      "description": "ISO 8601 timestamp when alert was created"
    },
    "expires": {
      "type":  "string",
      "format":  "date-time",
      "description": "ISO 8601 timestamp when alert should be removed (max 30 days from creation)"
    },
    "lastSeen": {
      "$ref": "#/$defs/locationEvent",
      "description": "Last known location and time the child was seen"
    },
    "contactInfo": {
      "$ref": "#/$defs/contactInfo",
      "description": "How to report sightings or information"
    },
    "circumstances": {
      "type": "string",
      "maxLength": 500,
      "description": "Brief description of disappearance circumstances"
    },
    "companionDescription": {
      "type": "string",
      "maxLength":  300,
      "description": "Description of person child may be with (if applicable)"
    },
    "vehicleDescription": {
      "type": "string",
      "maxLength": 200,
      "description": "Vehicle description if applicable"
    },
    "urgencyLevel": {
      "type":  "string",
      "enum": ["critical", "high", "standard"],
      "default": "standard",
      "description": "Alert urgency level affecting distribution priority"
    },
    "languageCode": {
      "type": "string",
      "pattern": "^[a-z]{2}$",
      "description": "ISO 639-1 language code for alert content"
    },
    "translations": {
      "type": "array",
      "items": {
        "$ref": "#/$defs/translation"
      },
      "description": "Translations of alert content in other languages"
    },
    "signature": {
      "$ref": "#/$defs/signature",
      "description": "Cryptographic signature from issuer"
    }
  },
  "additionalProperties": false,
  "$defs": {
    "issuerReference": {
      "type": "object",
      "required": ["id", "name", "country"],
      "properties": {
        "id": {
          "type": "string",
          "format": "uri",
          "description": "Issuer's OpenAmber profile URL"
        },
        "name": {
          "type": "string",
          "maxLength": 200,
          "description": "Organization name"
        },
        "country": {
          "type":  "string",
          "pattern": "^[A-Z]{2}$",
          "description": "ISO 3166-1 alpha-2 country code"
        },
        "type": {
          "type": "string",
          "enum": ["police", "hotline", "ngo", "government"],
          "description": "Type of issuing organization"
        }
      },
      "additionalProperties": false
    },
    "subjectDescription": {
      "type": "object",
      "required": ["givenName", "age", "physicalDescription"],
      "properties": {
        "givenName": {
          "type": "string",
          "maxLength": 100,
          "description": "Child's first name"
        },
        "familyName": {
          "type": "string",
          "maxLength": 100,
          "description": "Child's surname (may be withheld for privacy)"
        },
        "age": {
          "type":  "integer",
          "minimum":  0,
          "maximum":  17,
          "description": "Age in years"
        },
        "dateOfBirth": {
          "type": "string",
          "format": "date",
          "description": "Date of birth (optional, for age verification)"
        },
        "gender": {
          "type": "string",
          "enum": ["male", "female", "other", "unknown"],
          "description":  "Gender for identification purposes"
        },
        "physicalDescription": {
          "type": "string",
          "maxLength": 500,
          "description": "Height, hair color, eye color, distinguishing features"
        },
        "height": {
          "type": "object",
          "properties": {
            "value": {
              "type": "number",
              "minimum": 30,
              "maximum": 220
            },
            "unit": {
              "type": "string",
              "enum": ["cm", "in"],
              "default": "cm"
            }
          },
          "description": "Height measurement"
        },
        "weight": {
          "type": "object",
          "properties": {
            "value": {
              "type": "number",
              "minimum": 1,
              "maximum": 150
            },
            "unit":  {
              "type": "string",
              "enum": ["kg", "lb"],
              "default": "kg"
            }
          },
          "description": "Weight measurement"
        },
        "hairColor": {
          "type":  "string",
          "enum":  ["black", "brown", "blonde", "red", "gray", "white", "other"],
          "description": "Hair color"
        },
        "eyeColor": {
          "type":  "string",
          "enum":  ["brown", "blue", "green", "hazel", "gray", "other"],
          "description": "Eye color"
        },
        "distinguishingFeatures": {
          "type": "string",
          "maxLength": 300,
          "description": "Birthmarks, scars, tattoos, or other identifying features"
        },
        "photoHash": {
          "type": "string",
          "pattern": "^sha256:[a-f0-9]{64}$",
          "description": "SHA-256 hash of official photo"
        },
        "photoUrl": {
          "type": "string",
          "format": "uri",
          "description": "URL to retrieve photo from issuer's secure server"
        },
        "clothingDescription": {
          "type": "string",
          "maxLength": 300,
          "description": "What child was wearing when last seen"
        },
        "accessories": {
          "type": "string",
          "maxLength": 200,
          "description": "Glasses, jewelry, backpack, or other accessories"
        },
        "nationality": {
          "type": "string",
          "pattern": "^[A-Z]{2}$",
          "description": "ISO 3166-1 alpha-2 country code of nationality"
        },
        "spokenLanguages": {
          "type": "array",
          "items": {
            "type":  "string",
            "pattern": "^[a-z]{2}$"
          },
          "description":  "ISO 639-1 language codes of languages child speaks"
        }
      },
      "additionalProperties": false
    },
    "locationEvent": {
      "type": "object",
      "required": ["description", "timestamp"],
      "properties": {
        "description": {
          "type": "string",
          "maxLength": 300,
          "description": "Human-readable location description"
        },
        "coordinates": {
          "type": "array",
          "items": {
            "type": "number"
          },
          "minItems": 2,
          "maxItems": 2,
          "description": "[latitude, longitude] in WGS84 format"
        },
        "accuracy": {
          "type": "number",
          "minimum": 0,
          "description": "Location accuracy in meters"
        },
        "timestamp": {
          "type": "string",
          "format": "date-time",
          "description": "When child was last seen at this location"
        },
        "country": {
          "type": "string",
          "pattern": "^[A-Z]{2}$",
          "description": "ISO 3166-1 alpha-2 country code"
        },
        "region": {
          "type": "string",
          "maxLength": 100,
          "description": "Administrative region, state, or province"
        },
        "city": {
          "type": "string",
          "maxLength": 100,
          "description": "City or municipality name"
        },
        "postalCode": {
          "type": "string",
          "maxLength": 20,
          "description": "Postal or ZIP code"
        },
        "locationType": {
          "type":  "string",
          "enum":  [
            "residence",
            "school",
            "public_transport",
            "shopping_center",
            "park",
            "street",
            "other"
          ],
          "description": "Type of location"
        }
      },
      "additionalProperties": false
    },
    "contactInfo": {
      "type": "object",
      "properties": {
        "phone": {
          "type": "string",
          "pattern": "^\\+[0-9]{1,15}$",
          "description":  "Contact phone number in E.164 format"
        },
        "altPhone": {
          "type":  "string",
          "pattern":  "^\\+[0-9]{1,15}$",
          "description": "Alternative phone number"
        },
        "email":  {
          "type": "string",
          "format": "email",
          "description": "Contact email address"
        },
        "website": {
          "type": "string",
          "format": "uri",
          "description": "URL to alert details page"
        },
        "emergencyNumber": {
          "type": "string",
          "pattern": "^[0-9]{3}$",
          "description": "Local emergency number (e.g., 112, 911)"
        },
        "instructions": {
          "type": "string",
          "maxLength":  500,
          "description":  "Instructions for public on how to respond"
        },
        "availableHours": {
          "type":  "string",
          "maxLength": 100,
          "description": "Hours when contact is available (if not 24/7)"
        },
        "languages": {
          "type": "array",
          "items": {
            "type": "string",
            "pattern": "^[a-z]{2}$"
          },
          "description":  "Languages supported by contact center"
        }
      },
      "additionalProperties": false
    },
    "translation": {
      "type": "object",
      "required": ["languageCode"],
      "properties": {
        "languageCode": {
          "type": "string",
          "pattern": "^[a-z]{2}$",
          "description": "ISO 639-1 language code"
        },
        "physicalDescription": {
          "type": "string",
          "maxLength": 500
        },
        "clothingDescription": {
          "type": "string",
          "maxLength": 300
        },
        "circumstances": {
          "type": "string",
          "maxLength":  500
        },
        "instructions": {
          "type": "string",
          "maxLength":  500
        },
        "locationDescription": {
          "type":  "string",
          "maxLength": 300
        }
      },
      "additionalProperties": false
    },
    "signature": {
      "type": "object",
      "required": ["type", "created", "verificationMethod", "signatureValue"],
      "properties": {
        "type": {
          "const": "Ed25519Signature2020",
          "description": "Signature algorithm identifier"
        },
        "created": {
          "type":  "string",
          "format":  "date-time",
          "description": "Timestamp when signature was created"
        },
        "verificationMethod": {
          "type": "string",
          "format": "uri",
          "description": "URL to issuer's public key for verification"
        },
        "signatureValue": {
          "type": "string",
          "pattern": "^[A-Za-z0-9+/=._-]+$",
          "description":  "Base64-encoded Ed25519 signature"
        },
        "proofPurpose": {
          "type": "string",
          "enum": ["assertionMethod", "authentication"],
          "default": "assertionMethod",
          "description":  "Purpose of the proof"
        }
      },
      "additionalProperties": false
    }
  }
}