# CORS（跨域资源共享）

<a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS" class="external-link" target="_blank">CORS 或者「跨域资源共享」</a> 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

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」。

## 步骤

}

// Options define configuration options for Writer
type Options struct {
	// Directory defines the directory where log files will be written to.
	// If the directory does not exist, it will be created.
	Directory string

	// MaximumFileSize defines the maximum size of each log file in bytes.
	MaximumFileSize int64

	// FileNameFunc specifies the name a new file will take.

  if (Os.isFamily(Os.FAMILY_WINDOWS)) {
    // May be possible without, but autodetection is problematic on Windows 10
    // see https://github.com/palantir/gradle-graal
    // see https://www.graalvm.org/docs/reference-manual/native-image/#prerequisites
    windowsVsVarsPath("C:\\Program Files (x86)\\Microsoft Visual Studio\\2019\\BuildTools\\VC\\Auxiliary\\Build\\vcvars64.bat")
  }
}

mavenPublishing {

+ If referring to a repo other than `golang/go` you can use the
  `owner/repo#issue_number` syntax: `Fixes golang/tools#1234`
+ We do not use Signed-off-by lines in Go. Please don't add them.
  Our Gerrit server & GitHub bots enforce CLA compliance instead.

 */

package com.google.common.base;

import static java.util.concurrent.TimeUnit.NANOSECONDS;

import com.google.caliper.Benchmark;

/**
 * Simple benchmark: create, start, read. This does not currently report the most useful result
 * because it's ambiguous to what extent the stopwatch benchmark is being affected by GC.
 *
 * @author Kevin Bourrillion
 */
public class StopwatchBenchmark {
  @Benchmark

                .orElseGet(() -> modelLocator.locatePom(projectDirectory));
        if (!pom.equals(projectDirectory) && !pom.getParent().equals(projectDirectory)) {
            throw new IllegalArgumentException("The POM found does not belong to the given directory: " + pom);
        }
        return pom;
    }

    @Deprecated
    @Override
    public File locateExistingPom(File projectDirectory) {

<span style="color: green;">INFO</span>:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
```

</div>

## ✅ ⚫️

🚶 🎓 🩺: <a href="http://127.0.0.1:8000/docs" class="external-link" target="_blank">http://127.0.0.1:8000/docs</a>.

👆 🔜 👀 🕳 💖 👉:

<img src="/img/tutorial/security/image01.png">

/// check | "✔ 🔼 ❗"

👆 ⏪ ✔️ ✨ 🆕 "✔" 🔼.

 &amp; 👆 *➡ 🛠️* ✔️ 🐥 🔒 🔝-▶️️ ↩ 👈 👆 💪 🖊.

  CONDITIONAL_HOST_MOUNTS+="--mount type=bind,source=${HOME}/.netrc,destination=/home/.netrc,readonly "
fi

# echo ${CONDITIONAL_HOST_MOUNTS}

# This function checks if the file exists. If it does, it creates a randomly named host location
# for the file, adds it to the host KUBECONFIG, and creates a mount for it. Note that we use a copy
# of the original file, so that the container can write to it.

	binary.LittleEndian.PutUint32(bin[:], id)

	mac := hmac.New(sha256.New, key[:])
	mac.Write(bin[:])
	mac.Sum(partKey[:0])
	return partKey
}

// SealETag seals the etag using the object key.
// It does not encrypt empty ETags because such ETags indicate
// that the S3 client hasn't sent an ETag = MD5(object) and
// the backend can pick an ETag value.
func (key ObjectKey) SealETag(etag []byte) []byte {

 *
 * Note that the state progression is independent for each peer. Arriving at a gracefully-closed
 * state indicates that a peer has sent all of its outgoing messages and received all of its
 * incoming messages. But it does not guarantee that the other peer will successfully receive all of
 * its incoming messages.
 */
interface WebSocket {
  /** Returns the original request that initiated this web socket. */
  fun request(): Request