feat: RFC9421への対応を開始

SignatureBaseの生成をするために必要なものを作成

build.gradle.kts

@@ -4,7 +4,7 @@ plugins {
 }
 
 group = "dev.usbharu"
-version = "1.0.0"
+version = "2.0.0-SNAPSHOT"
 
 repositories {
     mavenCentral()

src/main/kotlin/dev/usbharu/httpsignature/v2/Component.kt

@@ -0,0 +1,9 @@
+package dev.usbharu.httpsignature.v2
+
+interface Component {
+    val componentName: String
+    val componentIdentifier: String
+        get() = "\"$componentName\":$componentParameter"
+    val componentParameter: String
+    val componentValue: String
+}

src/main/kotlin/dev/usbharu/httpsignature/v2/SignatureAlgorithm.kt

@@ -0,0 +1,6 @@
+package dev.usbharu.httpsignature.v2
+
+enum class SignatureAlgorithm(val value: String) {
+    ;
+
+}

src/main/kotlin/dev/usbharu/httpsignature/v2/SignatureBase.kt

@@ -0,0 +1,30 @@
+package dev.usbharu.httpsignature.v2
+
+class SignatureBase() {
+
+    private val list = mutableMapOf<String, Component>()
+
+    fun addComponent(component: Component) {
+        if (list[component.componentIdentifier] != null) {
+            throw IllegalArgumentException("Component with identifier ${component.componentIdentifier} already exists.")
+        }
+        list[component.componentIdentifier] = component
+    }
+
+    fun generateSignatureBase(signatureParameter: SignatureParameter): String {
+        val signatureBase =
+            list.values.joinToString(postfix = "\n") { component -> "${component.componentIdentifier}: ${component.componentValue}\n" }
+
+        val signatureParams = listOfNotNull(
+            list.keys.joinToString(" ", "(", ")"),
+            signatureParameter.algorithm?.let { algorithm -> "alg=\"${algorithm.value}\"" },
+            signatureParameter.keyId?.let { keyId -> "keyid=\"$keyId\"" },
+            signatureParameter.created?.let { created -> "created=$created" },
+            signatureParameter.expires?.let { expires -> "expires=$expires" },
+            signatureParameter.nonce?.let { nonce -> "nonce=\"$nonce\"" },
+            signatureParameter.tag?.let { tag -> "tag=\"$tag\"" },
+        ).joinToString(";", prefix = "\"@signature-params\": ")
+
+        return signatureBase + signatureParams
+    }
+}

src/main/kotlin/dev/usbharu/httpsignature/v2/SignatureParameter.kt

@@ -0,0 +1,12 @@
+package dev.usbharu.httpsignature.v2
+
+import java.time.Instant
+
+data class SignatureParameter(
+    val algorithm: SignatureAlgorithm?,
+    val keyId: String?,
+    val created: Instant?,
+    val expires: Instant?,
+    val nonce: String?,
+    val tag: String?,
+)