final Map<String, Object> result = indexUpdater.ingest(accessResult, doc);

        assertNotNull(result);
        // Result should be the same as input doc when ingester is null or doesn't modify
        assertSame(doc, result);
    }

    // Test ingest with exception in ingester
    @Test
    public void test_ingest_withException() {

    }

    /**
     * Registers this ingester with the ingest factory.
     * This makes the ingester available for processing documents.
     */
    public void register() {
        getIngestFactory().add(this);
    }

    /**
     * Gets the ingest factory instance for managing ingesters.
     *
     * @return the ingest factory instance
     */
    protected IngestFactory getIngestFactory() {

            return dataMap;
        }
        Map<String, Object> target = dataMap;
        for (final Ingester ingester : ingestFactory.getIngesters()) {
            try {
                target = ingester.process(target, paramMap);
            } catch (final Exception e) {
                logger.warn("[{}] Failed to process ingester", ingester.getClass().getSimpleName(), e);
            }
        }
        return target;
    }

     *
     * @param ingester the ingester to add
     */
    public synchronized void add(final Ingester ingester) {
        if (logger.isDebugEnabled()) {
            logger.debug("Loaded Ingester: {}", ingester.getClass().getSimpleName());
        }
        final Ingester[] newIngesters = Arrays.copyOf(ingesters, ingesters.length + 1);
        newIngesters[ingesters.length] = ingester;

            return map;
        }
        Map<String, Object> target = map;
        for (final Ingester ingester : ingestFactory.getIngesters()) {
            try {
                target = ingester.process(target, accessResult);
            } catch (final Exception e) {
                logger.warn("Failed to process Ingest[{}]", ingester.getClass().getSimpleName(), e);
            }
        }
        return target;
    }

        if (ingestFactory == null) {
            return resultData;
        }
        ResultData target = resultData;
        for (final Ingester ingester : ingestFactory.getIngesters()) {
            try {
                target = ingester.process(target, responseData);
            } catch (final Exception e) {

        factory.add(new TestIngester(2));
        factory.add(new TestIngester(1));
        Ingester[] ingesters = factory.getIngesters();
        assertEquals(1, ingesters[0].getPriority());
        assertEquals(2, ingesters[1].getPriority());
        assertEquals(3, ingesters[2].getPriority());
    }

    private static class TestIngester extends Ingester {
        public TestIngester(int priority) {
            this.priority = priority;

    }

    private static class TestIngestFactory extends IngestFactory {
        List<Ingester> ingesters = new ArrayList<>();

        @Override
        public Ingester[] getIngesters() {
            return ingesters.toArray(new Ingester[0]);
        }
    }

    private static class TestIngester extends Ingester {
        int processCalled = 0;

        @Override

# Body – Verschachtelte Modelle { #body-nested-models }

Mit **FastAPI** können Sie (dank Pydantic) beliebig tief verschachtelte Modelle definieren, validieren, dokumentieren und verwenden.

## Listen als Felder { #list-fields }

Sie können ein Attribut als Kindtyp definieren, zum Beispiel eine Python-`list`.

{* ../../docs_src/body_nested_models/tutorial001_py310.py hl[12] *}

# Body - 巢狀模型 { #body-nested-models }

使用 **FastAPI**，你可以定義、驗證、文件化，並使用任意深度的巢狀模型（感謝 Pydantic）。

## 列表欄位 { #list-fields }

你可以將屬性定義為某個子型別。例如，Python 的 `list`：

{* ../../docs_src/body_nested_models/tutorial001_py310.py hl[12] *}

這會讓 `tags` 成為一個列表，儘管尚未宣告列表元素的型別。

## 具有型別參數的列表欄位 { #list-fields-with-type-parameter }

不過，Python 有一種專門的方式來宣告具有內部型別（「型別參數」）的列表：

### 宣告帶有型別參數的 `list` { #declare-a-list-with-a-type-parameter }