feat: HttpRequestからSignature Baseを生成する処理を簡単にするやつを追加

src/main/kotlin/dev/usbharu/httpsignature/common/SignatureBaseBuilder.kt

@@ -11,6 +11,11 @@ class SignatureBaseBuilder {
         return signatureBase
     }
 
+    fun component(component: Component): SignatureBaseBuilder {
+        signatureBase.addComponent(component)
+        return this
+    }
+
     fun method(method: String): SignatureBaseBuilder {
         signatureBase.addComponent(DerivedComponent(DerivedComponentConstants.METHOD, "", method))
         return this

src/main/kotlin/dev/usbharu/httpsignature/utils/AbstractHttpRequestComponentExtractor.kt

@@ -0,0 +1,14 @@
+package dev.usbharu.httpsignature.utils
+
+import dev.usbharu.httpsignature.common.Component
+import dev.usbharu.httpsignature.common.HttpRequest
+
+abstract class AbstractHttpRequestComponentExtractor(protected val fieldProcessor: FieldProcessor) :
+    HttpRequestComponentExtractor {
+    override fun extract(name: String, request: HttpRequest): List<Component> {
+        val extractValue = extractValue(name, request)
+        return fieldProcessor.process(name, extractValue)
+    }
+
+    abstract fun extractValue(name: String, request: HttpRequest): List<String>
+}

src/main/kotlin/dev/usbharu/httpsignature/utils/CoveredComponent.kt

@@ -0,0 +1,3 @@
+package dev.usbharu.httpsignature.utils
+
+data class CoveredComponent(val fieldName: String, val componentParameterType: String)

src/main/kotlin/dev/usbharu/httpsignature/utils/FieldProcessor.kt

@@ -0,0 +1,7 @@
+package dev.usbharu.httpsignature.utils
+
+import dev.usbharu.httpsignature.common.Component
+
+fun interface FieldProcessor {
+    fun process(name: String, value: List<String>): List<Component>
+}

src/main/kotlin/dev/usbharu/httpsignature/utils/HttpRequestComponentExtractor.kt

@@ -0,0 +1,8 @@
+package dev.usbharu.httpsignature.utils
+
+import dev.usbharu.httpsignature.common.Component
+import dev.usbharu.httpsignature.common.HttpRequest
+
+interface HttpRequestComponentExtractor {
+    fun extract(name: String, request: HttpRequest): List<Component>
+}

src/main/kotlin/dev/usbharu/httpsignature/utils/HttpRequestSignatureBaseUtils.kt

@@ -0,0 +1,22 @@
+package dev.usbharu.httpsignature.utils
+
+import dev.usbharu.httpsignature.common.HttpRequest
+import dev.usbharu.httpsignature.common.SignatureBaseBuilder
+
+class HttpRequestSignatureBaseUtils {
+
+    private val fieldProcessorMap = mutableMapOf<String, HttpRequestComponentExtractor>()
+
+    fun from(httpRequest: HttpRequest, coveredComponents: List<CoveredComponent>): SignatureBaseBuilder {
+        val builder = SignatureBaseBuilder()
+        coveredComponents
+            .flatMap {
+                val extractor = (fieldProcessorMap[it.componentParameterType]
+                    ?: throw IllegalArgumentException("HttpRequestComponentExtractor ${it.componentParameterType} not found."))
+                extractor.extract(it.fieldName, httpRequest)
+            }.forEach {
+                builder.component(it)
+            }
+        return builder
+    }
+}