In this case, you could want to document how that external API *should* look like. What *path operation* it should have, what body it should expect, what response it should return, etc.

## An app with callbacks { #an-app-with-callbacks }

Let's see all this with an example.

Imagine you develop an app that allows creating invoices.

These invoices will have an `id`, `title` (optional), `customer`, and `total`.

        "overridden configs should be preserved"
    )
    assert '"deepLinking": true' not in response.text, (
        "overridden configs should not include the old value"
    )
    assert '"syntaxHighlight": false' not in response.text, (
        "not used parameters should not be included"
    )
    assert '"dom_id": "#swagger-ui"' in response.text, (
        "default configs should be preserved"
    )

                            null, "incomplete-project", null, "Should return null for missing groupId and version"),
                    Arguments.of("com.example", null, "1.0.0", "Should return null for missing artifactId"),
                    Arguments.of(null, null, "1.0.0", "Should return null for missing groupId and artifactId"),
                    Arguments.of("com.example", "test-project", null, "Should return null for missing version"),

    assert response.status_code == 422
    assert response.json() == {
        "detail": [
            {
                "type": "int_parsing",
                "loc": ["path", "item_id"],
                "msg": "Input should be a valid integer, unable to parse string as an integer",
                "input": "foobar",
            }
        ]
    }


def test_path_int_True():
    response = client.get("/path/int/True")

            assertTrue(result.success(), "Orchestrator should succeed");
            assertEquals(2, result.processedPoms().size(), "Should aggregate processed POMs");
            assertEquals(2, result.modifiedPoms().size(), "Should aggregate modified POMs");
            assertEquals(0, result.errorPoms().size(), "Should have no errors");
        }

        @Test
        @DisplayName("should handle strategy failures gracefully")

* `allow_origins` - A list of origins that should be permitted to make cross-origin requests. E.g. `['https://example.org', 'https://www.example.org']`. You can use `['*']` to allow any origin.
* `allow_origin_regex` - A regex string to match against origins that should be permitted to make cross-origin requests. e.g. `'https://.*\.example\.org'`.

        assertFalse(options.all().isPresent(), "--all should not be present by default");
        assertFalse(options.infer().isPresent(), "--infer should not be present by default");
        assertFalse(options.model().isPresent(), "--fix-model should not be present by default");
        assertFalse(options.model().isPresent(), "--model should not be present by default");

        // But the goal should be present

        assertTrue(nameIndex > 0, "Should contain name element");
        assertTrue(descriptionIndex > 0, "Should contain description element");
        assertTrue(propertiesIndex > 0, "Should contain properties element");

        // According to ELEMENT_ORDER: name should come before description, and properties should come much later
        assertTrue(nameIndex < descriptionIndex, "name should come before description");

            // groupId should also be removed (can be inferred from project)
            assertNull(DomUtils.findChildElement(dependency, "groupId"));
            // artifactId should remain (always required)
            assertNotNull(DomUtils.findChildElement(dependency, "artifactId"));
        }

        @Test
        @DisplayName("should keep dependency version for external artifact")

        assertTrue(resource.getIncludes().contains("*.xml"), "Should contain *.xml");
        assertTrue(resource.getIncludes().contains("*.properties"), "Should contain *.properties");

        // Verify persistence
        Resource resourceAfter = project.getResources().get(0);
        assertEquals(2, resourceAfter.getIncludes().size(), "Should still have two includes");