That's what all the systems with "login with Facebook, Google, Twitter, GitHub" use underneath.

### OAuth 1

There was an OAuth 1, which is very different from OAuth2, and more complex, as it included direct specifications on how to encrypt the communication.

It is not very popular or used nowadays.

OAuth2 doesn't specify how to encrypt the communication, it expects you to have your application served with HTTPS.

!!! tip

  @Nested
  @TestMetadata("analysis/analysis-api/testData/annotations/annotationsOnDeclaration/direct")
  @TestDataPath("$PROJECT_ROOT")
  public class Direct {
    @Test
    @TestMetadata("aliasedThrowsOnFunction.kt")
    public void testAliasedThrowsOnFunction() {
      runTest("analysis/analysis-api/testData/annotations/annotationsOnDeclaration/direct/aliasedThrowsOnFunction.kt");
    }

    @Test

                    artifact("direct-1.0-sources.jar")
                }
        direct.withModuleMetadata()
        direct.publish()

        buildFile << """
            resolveSources {
                expectedFiles = ['direct-1.0-sources.jar', 'transitive-1.0-sources.jar']
            }
        """
        expect:
        direct.pom.expectGet()
        direct.moduleMetadata.expectGet()

                }
            """

            file("direct/build.gradle") << """
                plugins {
                    id 'java'
                }

                dependencies {
                    implementation project(":transitive")
                }
            """
            file("direct/src/main/java/direct/Multiplier.java").java """
                package direct;

                public class Multiplier {

-- go.mod.orig --
module m

go 1.16

require direct v1.0.0

replace (
	direct v1.0.0 => ./direct
	indirect-with-pkg v1.0.0 => ./indirect-with-pkg
	indirect-without-pkg v1.0.0 => ./indirect-without-pkg
)
-- go.mod.use --
module m

go 1.16

require (
	direct v1.0.0
	indirect-with-pkg v1.0.0
)

replace (
	direct v1.0.0 => ./direct
	indirect-with-pkg v1.0.0 => ./indirect-with-pkg

	d.Write(padlen)

	if d.nx != 0 {
		panic("d.nx != 0")
	}

	var digest [Size]byte

	byteorder.BePutUint32(digest[0:], d.h[0])
	byteorder.BePutUint32(digest[4:], d.h[1])
	byteorder.BePutUint32(digest[8:], d.h[2])
	byteorder.BePutUint32(digest[12:], d.h[3])
	byteorder.BePutUint32(digest[16:], d.h[4])

	return digest
}

// ConstantTimeSum computes the same result of [Sum] but in constant time

            """ + buildFile.text

            file("direct/build.gradle") << """
                plugins {
                    id 'java-library'
                    id 'jacoco'
                }

                dependencies {
                    testImplementation project(":transitive")
                }
            """
            file("direct/src/main/java/direct/Multiplier.java").java """
                package direct;

apiVersion: v1
entries:
  minio:
  - apiVersion: v1
    appVersion: RELEASE.2024-04-18T19-09-19Z
    created: "2024-04-28T03:14:12.227568814-07:00"
    description: High Performance Object Storage
    digest: 8ef4212d7d51be6c8192b3e91138a9ca918ca56142c42500028cfd3b80e0b2dd
    home: https://min.io
    icon: https://min.io/resources/img/logo/MINIO_wordmark.png
    keywords:
    - minio
    - storage
    - object-storage
    - s3

        .add("WWW-Authenticate", "Digest,Basic realm=\"myrealm\"")
        .build()
    assertThat(headers.parseChallenges("WWW-Authenticate")).containsExactly(
      Challenge("Digest", mapOf()),
      Challenge("Basic", mapOf("realm" to "myrealm")),
    )
  }

  @Test fun multipleSeparatorsBetweenChallenges() {
    val headers =
      Headers.Builder()
        .add("WWW-Authenticate", "Digest,,,, Basic ,,realm=\"myrealm\"")

  @Nested
  @TestMetadata("analysis/analysis-api/testData/annotations/annotationsOnDeclaration/direct")
  @TestDataPath("$PROJECT_ROOT")
  public class Direct {
    @Test
    @TestMetadata("aliasedThrowsOnFunction.kt")
    public void testAliasedThrowsOnFunction() {
      runTest("analysis/analysis-api/testData/annotations/annotationsOnDeclaration/direct/aliasedThrowsOnFunction.kt");
    }

    @Test