https://yourapi.com/invoices/?callback_url=https://www.external.org/events
```

con un JSON body de:

```JSON
{
    "id": "2expen51ve",
    "customer": "Mr. Richie Rich",
    "total": "9999"
}
```

luego *tu API* procesará la factura y, en algún momento después, enviará un request de callback al `callback_url` (la *API externa*):

```
https://www.external.org/events/invoices/2expen51ve
```

 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */
package org.codelibs.core.misc;

/**

 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,

 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,

 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,

 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

///

The `status_code` parameter receives a number with the HTTP status code.

/// info

`status_code` can alternatively also receive an `IntEnum`, such as Python's <a href="https://docs.python.org/3/library/http.html#http.HTTPStatus" class="external-link" target="_blank">`http.HTTPStatus`</a>.

///

It will:

* Return that status code in the response.

/**
 * This package contains non-functional annotations which are
 * used to tag various elements and help users understanding
 * how those types should be used.
 *
 * @since 4.0.0
 */
@Experimental

<?xml version="1.0" encoding="UTF-8"?><metadata>
  <groupId>org.apache.maven.its.mng3906</groupId>
  <artifactId>b</artifactId>
  <version>0.1</version>
  <versioning>
    <release>0.1</release>
    <versions>
      <version>0.1</version>
    </versions>
    <lastUpdated>20081214111129</lastUpdated>
  </versioning>

<?xml version="1.0" encoding="UTF-8"?><metadata>
  <groupId>org.apache.maven.its.mng3906</groupId>
  <artifactId>e</artifactId>
  <version>0.1</version>
  <versioning>
    <release>0.1</release>
    <versions>
      <version>0.1</version>
    </versions>
    <lastUpdated>20081214111155</lastUpdated>
  </versioning>