{* ../../docs_src/advanced_middleware/tutorial001_py310.py hl[2,6] *}

## `TrustedHostMiddleware` { #trustedhostmiddleware }

Enforces that all incoming requests have a correctly set `Host` header, in order to guard against HTTP Host Header attacks.

{* ../../docs_src/advanced_middleware/tutorial002_py310.py hl[2,6:8] *}

The following arguments are supported:

	testCases := []struct {
		host        string
		port        int
		expectedErr error
	}{
		{"", port, fmt.Errorf("listen tcp :%v: bind: address already in use", port)},
		{"127.0.0.1", port, fmt.Errorf("listen tcp 127.0.0.1:%v: bind: address already in use", port)},
	}

	for _, testCase := range testCases {
		err := CheckPortAvailability(testCase.host, strconv.Itoa(testCase.port), TCPOptions{})
		switch {

        testData.add(createRelatedContent("term1", "Content for host2", "host2"));
        testData.add(createRelatedContent("term2", "Content for default", ""));
        mockBhv.setTestData(testData);

        int count = relatedContentHelper.load();
        assertEquals(3, count); // Three virtual host keys: "host1", "host2", ""
    }

    @Test

import uvicorn
from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def root():
    a = "a"
    b = "b" + a
    return {"hello world": b}


if __name__ == "__main__":

import org.junit.Assert.assertEquals
import org.junit.Test

class IdnaTest {
  @Test
  fun testHostnameFunction() {
    assertEquals("xn--n3h.net", "https://☃.net/robots.txt".toHttpUrl().host)
  }

            }

            // Validate virtual host path to prevent path traversal
            final String virtualHostPath = values[0];
            if (!isValidVirtualHostPath(virtualHostPath)) {
                logger.warn("Invalid virtual host path detected: path={}", virtualHostPath);

 */
package org.codelibs.fess.app.web.api.admin.duplicatehost;

import org.codelibs.fess.app.web.admin.duplicatehost.CreateForm;

/**
 * Request body for creating duplicate host via REST API.
 * Extends CreateForm to inherit validation and field definitions.
 */
public class CreateBody extends CreateForm {

    /**
     * Creates a new CreateBody instance.
     */
    public CreateBody() {

from fastapi import FastAPI, Header
from pydantic import BaseModel

app = FastAPI()


class CommonHeaders(BaseModel):
    host: str
    save_data: bool
    if_modified_since: str | None = None
    traceparent: str | None = None
    x_tag: list[str] = []


@app.get("/items/")
async def read_items(headers: CommonHeaders = Header(convert_underscores=False)):

  /**
   * Don't call through to the proxy selector if we don't have a host name.
   * https://github.com/square/okhttp/issues/5770
   */
  @Test fun proxySelectorNotCalledForNullHost() {
    // The string '>' is okay in a hostname in HttpUrl, which does very light hostname validation.
    // It is not okay in URI, and so it's stripped and we get a URI with a null host.
    val bogusHostname = ">"
    val address =

	query.Set("X-Amz-Expires", strconv.FormatInt(expires, 10))
	query.Set("X-Amz-SignedHeaders", "host")
	query.Set("X-Amz-Credential", credential)
	query.Set("X-Amz-Content-Sha256", unsignedPayload)

	// "host" is the only header required to be signed for Presigned URLs.
	extractedSignedHeaders := make(http.Header)
	extractedSignedHeaders.Set("host", req.Host)

	queryStr := strings.ReplaceAll(query.Encode(), "+", "%20")