# OpenAPI Breaking Change Diff (`gmoran/openapi-breaking-change-diff`) Actor

Compare two public OpenAPI JSON specifications and return an explainable, structured API change set.

- **URL**: https://apify.com/gmoran/openapi-breaking-change-diff.md
- **Developed by:** [Guillermo Morán](https://apify.com/gmoran) (community)
- **Stats:** 2 total users, 1 monthly users, 100.0% runs succeeded, 0 bookmarks
- **User rating**: No ratings yet

## Pricing

from $3.00 / 1,000 structured api changes

This Actor is paid per event. You are not charged for the Apify platform usage, but only a fixed price for specific events.

Learn more: https://docs.apify.com/actors/running/actors-in-store.md#pay-per-event

## What's an Apify Actor?

An Actor is a serverless cloud program that runs on the Apify platform. It has two run modes.
In Batch mode, an Actor accepts a well-defined JSON input, performs an action which can take anything from a few seconds to a few hours,
and optionally produces a well-defined JSON output, datasets with results, or files in key-value store.
In Standby mode, an Actor provides a web server which can be used as a website, API, or an MCP server.

Apify vocabulary and the platform model are defined once, in the agent quickstart at https://apify.com/agents.md.

## How to integrate an Actor?

If asked about integration, you help developers integrate Actors into their projects.
You adapt to their stack and deliver integrations that are safe, well-documented, and production-ready.

Do not guess an integration path. Every one of them is in the agent quickstart at https://apify.com/agents.md: the Apify MCP server, Agent Skills with the Apify CLI, the JavaScript and Python clients, the REST API, and the account-free path for an agent with no human to sign in. It also carries the rule on stating cost before the first paid run.

For examples already wired to this Actor's own input schema, see the [API](#api) section below.

Each client library has reference documentation the quickstart does not restate: [JavaScript/TypeScript](https://docs.apify.com/api/client/js/docs.md) (`npm install apify-client`) and [Python](https://docs.apify.com/api/client/python/docs.md) (`pip install apify-client`).

# README

## OpenAPI Breaking Change Diff

Compare two **public OpenAPI JSON** specifications and export a deterministic, traceable API change set.

It is for API owners, SDK maintainers, QA teams, integration developers, and technical product teams that need an automatable answer to: *what changed between these two API contracts?*

### What it does

- Fetches two public HTTP(S) OpenAPI JSON documents.
- Finds added, removed, and modified HTTP operations.
- Emits one structured Dataset item per change; identical specifications produce one `NO_CHANGES` item so automation can still consume the result.
- Saves a `SUMMARY` record with operation totals, change counts, and truncation status.

### Why this Actor

- **No LLM required.**
- **No paid API or login required.**
- Deterministic comparison and explainable changed-field lists.
- Bounded output (`maxChanges` is 1–500).
- Useful from the Apify Console or API.

### Input

```json
{
  "beforeUrl": "https://petstore3.swagger.io/api/v3/openapi.json",
  "afterUrl": "https://petstore3.swagger.io/api/v3/openapi.json",
  "maxChanges": 10
}
```

Both inputs must be public OpenAPI **JSON** URLs. YAML conversion and persistent monitoring are intentionally out of scope for this small Actor.

### Output

Each Dataset row includes `changeType`, `path`, `method`, the old/new operation IDs, deterministic field-level details, and both source URLs. The default Key-Value Store `SUMMARY` record reconciles the result counts.

### Privacy and limits

The Actor fetches only the two public URLs supplied in its input. It does not crawl API endpoints, collect user data, use browser automation, or retain data outside normal Apify run storage.

# Actor input Schema

## `beforeUrl` (type: `string`):

Public HTTP(S) URL of the earlier OpenAPI JSON specification.

## `afterUrl` (type: `string`):

Public HTTP(S) URL of the later OpenAPI JSON specification.

## `maxChanges` (type: `integer`):

Maximum number of structured change records to save, from 1 to 500.

## Actor input object example

```json
{
  "beforeUrl": "https://petstore3.swagger.io/api/v3/openapi.json",
  "afterUrl": "https://petstore3.swagger.io/api/v3/openapi.json",
  "maxChanges": 10
}
```

# Actor output Schema

## `changes` (type: `string`):

No description

## `summary` (type: `string`):

No description

# API

You can run this Actor programmatically using our API. Below are code examples in JavaScript, Python, and CLI, as well as the OpenAPI specification and MCP server setup.

## JavaScript example

```javascript
import { ApifyClient } from 'apify-client';

// Initialize the ApifyClient with your Apify API token
// Replace the '<YOUR_API_TOKEN>' with your token
const client = new ApifyClient({
    token: '<YOUR_API_TOKEN>',
});

// Prepare Actor input
const input = {
    "beforeUrl": "https://petstore3.swagger.io/api/v3/openapi.json",
    "afterUrl": "https://petstore3.swagger.io/api/v3/openapi.json",
    "maxChanges": 10
};

// Run the Actor and wait for it to finish
const run = await client.actor("gmoran/openapi-breaking-change-diff").call(input);

// Fetch and print Actor results from the run's dataset (if any)
console.log('Results from dataset');
console.log(`💾 Check your data here: https://console.apify.com/storage/datasets/${run.defaultDatasetId}`);
const { items } = await client.dataset(run.defaultDatasetId).listItems();
items.forEach((item) => {
    console.dir(item);
});

// 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/js/docs

```

## Python example

```python
from apify_client import ApifyClient

# Initialize the ApifyClient with your Apify API token
# Replace '<YOUR_API_TOKEN>' with your token.
client = ApifyClient("<YOUR_API_TOKEN>")

# Prepare the Actor input
run_input = {
    "beforeUrl": "https://petstore3.swagger.io/api/v3/openapi.json",
    "afterUrl": "https://petstore3.swagger.io/api/v3/openapi.json",
    "maxChanges": 10,
}

# Run the Actor and wait for it to finish
run = client.actor("gmoran/openapi-breaking-change-diff").call(run_input=run_input)

# Fetch and print Actor results from the run's dataset (if there are any)
print(f"💾 Check your data here: https://console.apify.com/storage/datasets/{run.default_dataset_id}")
for item in client.dataset(run.default_dataset_id).iterate_items():
    print(item)

# 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/python/docs/quick-start

```

## CLI example

```bash
echo '{
  "beforeUrl": "https://petstore3.swagger.io/api/v3/openapi.json",
  "afterUrl": "https://petstore3.swagger.io/api/v3/openapi.json",
  "maxChanges": 10
}' |
apify call gmoran/openapi-breaking-change-diff --silent --output-dataset

```

## MCP server setup

```json
{
    "mcpServers": {
        "apify": {
            "type": "http",
            "url": "https://mcp.apify.com/?tools=fetch-actor-details,gmoran/openapi-breaking-change-diff"
        }
    }
}
```

The hosted server signs you in with OAuth on first connect, so no API token belongs in this config. Clients without OAuth support can send an `Authorization: Bearer <APIFY_API_TOKEN>` header instead, using a token from API & Integrations in Apify Console (https://console.apify.com/settings/integrations).

## OpenAPI specification

Download the OpenAPI definition: https://api.apify.com/v2/actors/h1oPQAcM7C7iPJd6s/builds/EcFfYE9kFhT78BeOv/openapi.json