# Structured data monitor for webpage schema changes

**Use case:** 

Monitor JSON-LD, canonical, Open Graph, hreflang, robots, microdata, and RDFa changes on public webpages.

## Input

```json
{
  "startUrls": [
    {
      "url": "https://www.imdb.com/title/tt0111161/"
    }
  ],
  "snapshotKey": "movie-schema-monitor",
  "emitMode": "all",
  "maxUrls": 5
}
```

## Output

```json
{
  "url": {
    "label": "URL",
    "format": "link"
  },
  "canonicalUrl": {
    "label": "Canonical",
    "format": "link"
  },
  "changed": {
    "label": "Changed"
  },
  "severity": {
    "label": "Severity"
  },
  "changeCount": {
    "label": "Changes"
  },
  "statusCode": {
    "label": "Status"
  },
  "fetchedAt": {
    "label": "Fetched",
    "format": "date"
  },
  "contentHash": {
    "label": "Hash"
  },
  "snapshotKey": {
    "label": "Snapshot store"
  },
  "changes": {
    "label": "Change details",
    "format": "object"
  },
  "current": {
    "label": "Current data",
    "format": "object"
  },
  "errorType": {
    "label": "Error type"
  },
  "errorMessage": {
    "label": "Error"
  }
}
```

## About this Actor

This example demonstrates how to use [Webpage Structured Data Monitor](https://apify.com/automation-lab/webpage-structured-data-monitor) with a specific input configuration. Visit the [Actor detail page](https://apify.com/automation-lab/webpage-structured-data-monitor) to learn more, explore other use cases, and run it yourself.