## Pin your `fastapi` version

The first thing you should do is to "pin" the version of **FastAPI** you are using to the specific latest version that you know works correctly for your application.

For example, let's say you are using version `0.45.0` in your app.

      for (Certificate certificate : chain.connection().handshake().peerCertificates()) {
        String pin = CertificatePinner.pin(certificate);
        if (denylist.contains(pin)) {
          throw new IOException("Denylisted peer certificate: " + pin);
        }
      }
      return chain.proceed(chain.request());
    }
  };

  private final OkHttpClient client = new OkHttpClient.Builder()

import kotlin.test.assertFailsWith
import mockwebserver3.MockResponse
import mockwebserver3.MockWebServer
import mockwebserver3.SocketPolicy.DisconnectAtEnd
import okhttp3.CertificatePinner
import okhttp3.CertificatePinner.Companion.pin
import okhttp3.OkHttpClientTestRule
import okhttp3.RecordingHostnameVerifier
import okhttp3.Request
import okhttp3.internal.platform.Platform.Companion.get
import okhttp3.testing.PlatformRule

    assertFalse(pin.matchesHostname("www.example.com"))
  }

  @Test fun testMatchesSha256() {
    val pin = Pin("example.com", certA1Sha256Pin)
    assertTrue(pin.matchesCertificate(certA1.certificate))
    assertFalse(pin.matchesCertificate(certB1.certificate))
  }

  @Test fun testMatchesSha1() {
    val pin = Pin("example.com", certC1Sha1Pin)
    assertTrue(pin.matchesCertificate(certC1.certificate))

    Assertions.assertTrue(pin.matchesCertificate(certA1.certificate))
    Assertions.assertFalse(pin.matchesCertificate(certB1.certificate))
  }

  @Test
  fun testMatchesSha1() {
    val pin = CertificatePinner.Pin("example.com", certC1Sha1Pin)
    Assertions.assertTrue(pin.matchesCertificate(certC1.certificate))
    Assertions.assertFalse(pin.matchesCertificate(certB1.certificate))

      when {
        pin.startsWith("sha1/") -> {
          this.hashAlgorithm = "sha1"
          this.hash = pin.substring("sha1/".length).decodeBase64() ?: throw IllegalArgumentException("Invalid pin hash: $pin")
        }
        pin.startsWith("sha256/") -> {
          this.hashAlgorithm = "sha256"

# TODO(b/304751256): Adjust the numpy pin to a single version, when ready
numpy ~= 1.23.5 ; python_version <= "3.11"
numpy ~= 1.26.0 ; python_version >= "3.12"
wheel ~= 0.41.2
h5py >= 3.10.0
lit ~= 17.0.2
opt_einsum == 3.3.0
astunparse == 1.6.3
dill == 0.3.7
astor == 0.7.1
typing_extensions == 4.8.0
gast == 0.4.0
termcolor == 2.3.0
wrapt == 1.16.0
tblib == 2.0.0

# Install tensorboard, and keras

      if (!response.isSuccessful) throw IOException("Unexpected code $response")

      for (certificate in response.handshake!!.peerCertificates) {
        println(CertificatePinner.pin(certificate))
      }
    }
  }
}

fun main() {
  CertificatePinning().run()

          if (!response.isSuccessful) throw IOException("Unexpected code $response")

          for (certificate in response.handshake!!.peerCertificates) {
            println(CertificatePinner.pin(certificate))
          }
        }
      }
    ```
=== ":material-language-java: Java"
    ```java
      private final OkHttpClient client = new OkHttpClient.Builder()
          .certificatePinner(

import javax.net.ssl.SSLSession
import javax.net.ssl.X509TrustManager
import kotlin.test.assertFailsWith
import mockwebserver3.MockResponse
import mockwebserver3.MockWebServer
import okhttp3.CertificatePinner.Companion.pin
import okhttp3.testing.PlatformRule
import okhttp3.tls.HandshakeCertificates
import okhttp3.tls.HeldCertificate
import org.junit.jupiter.api.BeforeEach
import org.junit.jupiter.api.Tag
import org.junit.jupiter.api.Test