# CORS（跨域资源共享） { #cors-cross-origin-resource-sharing }

[CORS 或者「跨域资源共享」](https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS) 指浏览器中运行的前端拥有与后端通信的 JavaScript 代码，而后端处于与前端不同的「源」的情况。

## 源 { #origin }

源是协议（`http`，`https`）、域（`myapp.com`，`localhost`，`localhost.tiangolo.com`）以及端口（`80`、`443`、`8080`）的组合。

因此，这些都是不同的源：

* `http://localhost`
* `https://localhost`
* `http://localhost:8080`

即使它们都在 `localhost` 中，但是它们使用不同的协议或者端口，所以它们都是不同的「源」。

                            name = s;
                            value = StringUtil.EMPTY;
                        } else {
                            name = s.substring(0, pos);
                            value = s.substring(pos + 1);
                        }
                        return new BasicNameValuePair(name, value);
                    }).collect(Collectors.toList()));

    }

    private BytesReference buildBigExample(String extraText) throws IOException {
        String bigger = read300BytesExample().utf8ToString();
        bigger = "{\"huge\": \"" + extraText + "\"," + bigger.substring(1);
        return new BytesArray(bigger);
    }

    @Benchmark
    public BytesReference filterObjects() throws IOException {
        SourceLookup lookup = new SourceLookup();
        lookup.setSource(sourceBytes);

            return "";
        }
        final int pos = resourceName.lastIndexOf("/");
        if (pos == -1 || pos == resourceName.length() - 1) {
            return "";
        }
        return resourceName.substring(pos + 1);
    }

    private void pad(StringBuilder buffer, int spaces) {
        String block = "                                        ";
        while (spaces > 0) {

                                } else {
                                    break;
                                }
                            }

                            string = string.substring(0, i + 1).trim();
                            output.put(string, string);
                            System.out.print(o);
                        }
                    },
                    true))) {

        validator.validateRawModel(model, request, problems);

        return problems;
    }

    private void assertContains(String msg, String substring) {
        assertTrue(msg.contains(substring), "\"" + substring + "\" was not found in: " + msg);
    }

    @BeforeEach
    void setUp() throws Exception {
        validator = new DefaultModelValidator(new DefaultModelVersionProcessor());

                try {
                    boolean isDelete = false;
                    if (targetWord.startsWith(DELETE_PREFIX)) {
                        isDelete = true;
                        targetWord = targetWord.substring(2);
                    }
                    final String target = targetWord;
                    BadWord badWord = badWordBhv.selectEntity(cb -> cb.query().setSuggestWord_Equal(target)).orElse(null);//TODO

For internal purposes, we use binary formats for their brevity.
We use the `Serializer` abstraction to separate the actual implementation of serialization from its uses.

When sharing data with external tools, we use JSON.

## Consequences

* The configuration cache serialization infrastructure should be used for all serialization.

 * proportional to the highest valued character that has a replacement. For example a replacement
 * map containing the single character '{@literal \}u1000' will require approximately 16K of memory.
 * As such sharing this data structure between escaper instances is the primary goal of this class.
 *
 * @author David Beaumont
 * @since 15.0
 */
@GwtCompatible
public final class ArrayBasedEscaperMap {
  /**

допомогою префікса `X-`](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers).

Але якщо у вас є власні заголовки, які клієнт у браузері має бачити, вам потрібно додати їх у вашу конфігурацію CORS (докладніше в [CORS (Cross-Origin Resource Sharing)](../tutorial/cors.md)), використовуючи параметр `expose_headers`, задокументований у [документації Starlette щодо CORS](https://www.starlette.dev/middleware/#corsmiddleware)....