Implement createPresentationFromCredentials

build.gradle.kts

@@ -157,6 +157,9 @@ subprojects {
 
   tasks.test {
     useJUnitPlatform()
+    reports {
+      junitXml
+    }
     testLogging {
       events("passed", "skipped", "failed", "standardOut", "standardError")
       exceptionFormat = TestExceptionFormat.FULL

credentials/src/main/kotlin/web5/sdk/credentials/PresentationExchange.kt

@@ -7,6 +7,11 @@ import com.nfeld.jsonpathkt.JsonPath
 import com.nfeld.jsonpathkt.extension.read
 import com.nimbusds.jwt.JWTParser
 import com.nimbusds.jwt.SignedJWT
+import web5.sdk.credentials.model.DescriptorMap
+import web5.sdk.credentials.model.InputDescriptorV2
+import web5.sdk.credentials.model.PresentationDefinitionV2
+import web5.sdk.credentials.model.PresentationSubmission
+import java.util.UUID
 
 /**
  * The `PresentationExchange` object provides functions for working with Verifiable Credentials
@@ -65,6 +70,52 @@ public object PresentationExchange {
     }
   }
 
+  /**
+   * Creates a Presentation Submission in which the list of Verifiable Credentials JWTs (VCs) fulfills the given Presentation Definition. 
+   * Presentation Definition.
+   *
+   *
+   * @param vcJwts Iterable of VCs in JWT format to validate.
+   * @param presentationDefinition The Presentation Definition V2 object against which VCs are validated.
+   * @return A PresentationSubmission object.
+   * @throws UnsupportedOperationException if the presentation definition contains submission requirements.
+   * @throws IllegalStateException if no VC corresponds to an input descriptor or if a VC's index is not found.
+   * @throws PresentationExchangeError If the number of input descriptors matched is less than required.
+   */
+  public fun createPresentationFromCredentials(
+    vcJwts: Iterable<String>,
+    presentationDefinition: PresentationDefinitionV2
+  ): PresentationSubmission {
+
+    satisfiesPresentationDefinition(vcJwts, presentationDefinition)
+
+    val inputDescriptorToVcMap = mapInputDescriptorsToVCs(vcJwts, presentationDefinition)
+    val vcJwtToIndexMap = vcJwts.withIndex().associate { (index, vcJwt) -> vcJwt to index }
+
+    val descriptorMapList = mutableListOf<DescriptorMap>()
+    for ((inputDescriptor, vcList) in inputDescriptorToVcMap) {
+      // Even if multiple VCs satisfy the input descriptor we use the first
+      val vcJwt = vcList.firstOrNull()
+      checkNotNull(vcJwt) { "Illegal state: no vc corresponds to input descriptor" }
+
+      val vcIndex = vcJwtToIndexMap[vcJwt]
+      checkNotNull(vcIndex) { "Illegal state: vcJwt index not found" }
+
+      descriptorMapList.add(
+        DescriptorMap(
+          id = inputDescriptor.id,
+          path = "$.verifiableCredential[$vcIndex]",
+          format = "jwt_vc"
+        ))
+    }
+
+    return PresentationSubmission(
+      id = UUID.randomUUID().toString(),
+      definitionId = presentationDefinition.id,
+      descriptorMap = descriptorMapList
+    )
+  }
+
   private fun mapInputDescriptorsToVCs(
     vcJwtList: Iterable<String>,
     presentationDefinition: PresentationDefinitionV2
@@ -102,7 +153,7 @@ public object PresentationExchange {
       ?: throw JsonPathParseException()
 
     // If the Input Descriptor has constraints and fields defined, evaluate them.
-    inputDescriptor.constraints?.fields?.let { fields ->
+    inputDescriptor.constraints.fields?.let { fields ->
       val requiredFields = fields.filter { field -> field.optional != true }
 
       for (field in requiredFields) {

credentials/src/main/kotlin/web5/sdk/credentials/PresentationDefinition.kt → credentials/src/main/kotlin/web5/sdk/credentials/model/PresentationDefinition.kt

@@ -1,4 +1,4 @@
-package web5.sdk.credentials
+package web5.sdk.credentials.model
 
 import com.fasterxml.jackson.annotation.JsonIgnore
 import com.fasterxml.jackson.annotation.JsonProperty

credentials/src/main/kotlin/web5/sdk/credentials/model/PresentationSubmission.kt

@@ -0,0 +1,29 @@
+package web5.sdk.credentials.model
+
+import com.fasterxml.jackson.annotation.JsonInclude
+import com.fasterxml.jackson.annotation.JsonProperty
+
+/**
+ * Represents a presentation submission object.
+ *
+ * @see [Presentation Submission](https://identity.foundation/presentation-exchange/spec/v2.0.0/#presentation-submission)
+ */
+public class PresentationSubmission(
+  public val id: String,
+  @JsonProperty("definition_id")
+  public val definitionId: String,
+  @JsonProperty("descriptor_map")
+  public val descriptorMap: List<DescriptorMap>
+)
+
+/**
+ * Represents descriptor map for a presentation submission.
+ */
+@JsonInclude(JsonInclude.Include.NON_NULL)
+public class DescriptorMap(
+  public val id: String,
+  public val format: String,
+  public val path: String,
+  @JsonProperty("path_nested")
+  public val pathNested: DescriptorMap? = null
+)

credentials/src/test/kotlin/web5/sdk/credentials/PresentationDefinitionTest.kt

@@ -11,6 +11,10 @@ import org.erdtman.jcs.JsonCanonicalizer
 import org.junit.jupiter.api.Assertions.assertEquals
 import org.junit.jupiter.api.Test
 import org.junit.jupiter.api.assertDoesNotThrow
+import web5.sdk.credentials.model.ConstraintsV2
+import web5.sdk.credentials.model.FieldV2
+import web5.sdk.credentials.model.InputDescriptorV2
+import web5.sdk.credentials.model.PresentationDefinitionV2
 import java.io.File
 
 class PresentationDefinitionTest {

credentials/src/test/kotlin/web5/sdk/credentials/PresentationExchangeTest.kt

@@ -8,10 +8,13 @@ import com.fasterxml.jackson.module.kotlin.registerKotlinModule
 import org.junit.jupiter.api.Nested
 import org.junit.jupiter.api.assertDoesNotThrow
 import org.junit.jupiter.api.assertThrows
+import web5.sdk.credentials.model.PresentationDefinitionV2
 import web5.sdk.crypto.InMemoryKeyManager
 import web5.sdk.dids.methods.key.DidKey
 import java.io.File
 import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertNotNull
 
 data class DateOfBirth(val dateOfBirth: String)
 data class Address(val address: String)
@@ -326,4 +329,102 @@ class PresentationExchangeTest {
       }.messageContains("Missing input descriptors: The presentation definition requires")
     }
   }
+
+  @Nested
+  inner class CreatePresentationFromCredentials {
+    @Test
+    fun `creates valid submission when VC satisfies tbdex PD`() {
+      val pd = jsonMapper.readValue(
+        readPd("src/test/resources/pd_sanctions.json"),
+        PresentationDefinitionV2::class.java
+      )
+
+      val presentationSubmission = PresentationExchange.createPresentationFromCredentials(listOf(sanctionsVcJwt), pd)
+
+      assertNotNull(presentationSubmission.id)
+      assertEquals(pd.id, presentationSubmission.definitionId)
+
+      assertEquals(1, presentationSubmission.descriptorMap.size)
+      assertNotNull(presentationSubmission.descriptorMap[0].id)
+      assertEquals("jwt_vc", presentationSubmission.descriptorMap[0].format)
+      assertEquals("$.verifiableCredential[0]", presentationSubmission.descriptorMap[0].path)
+    }
+
+    @Test
+    fun `creates valid submission when VC satisfies PD with no filter dob filed constraint and extra VC`() {
+      val pd = jsonMapper.readValue(
+        readPd("src/test/resources/pd_path_no_filter_dob.json"),
+        PresentationDefinitionV2::class.java
+      )
+
+      val vc1 = VerifiableCredential.create(
+        type = "DateOfBirth",
+        issuer = issuerDid.uri,
+        subject = holderDid.uri,
+        data = DateOfBirth(dateOfBirth = "Data1")
+      )
+      val vcJwt1 = vc1.sign(issuerDid)
+
+      val vc2 = VerifiableCredential.create(
+        type = "Address",
+        issuer = issuerDid.uri,
+        subject = holderDid.uri,
+        data = Address("abc street 123")
+      )
+      val vcJwt2 = vc2.sign(issuerDid)
+
+      val presentationSubmission = PresentationExchange.createPresentationFromCredentials(listOf(vcJwt2, vcJwt1), pd)
+
+      assertEquals(1, presentationSubmission.descriptorMap.size)
+      assertEquals("$.verifiableCredential[1]", presentationSubmission.descriptorMap[0].path)
+    }
+
+    @Test
+    fun `throws when VC does not satisfy sanctions requirements`() {
+      val pd = jsonMapper.readValue(
+        readPd("src/test/resources/pd_sanctions.json"),
+        PresentationDefinitionV2::class.java
+      )
+      val vc = VerifiableCredential.create(
+        type = "StreetCred",
+        issuer = issuerDid.uri,
+        subject = holderDid.uri,
+        data = StreetCredibility(localRespect = "high", legit = true)
+      )
+      val vcJwt = vc.sign(issuerDid)
+
+      assertFailure {
+        PresentationExchange.createPresentationFromCredentials(listOf(vcJwt), pd)
+      }.messageContains("Missing input descriptors: The presentation definition requires")
+    }
+
+    @Test
+    fun `creates valid submission when VC two vcs satisfy the same input descriptor`() {
+      val pd = jsonMapper.readValue(
+        readPd("src/test/resources/pd_path_no_filter_dob.json"),
+        PresentationDefinitionV2::class.java
+      )
+
+      val vc1 = VerifiableCredential.create(
+        type = "DateOfBirth",
+        issuer = issuerDid.uri,
+        subject = holderDid.uri,
+        data = DateOfBirth(dateOfBirth = "11/11/2011")
+      )
+      val vcJwt1 = vc1.sign(issuerDid)
+
+      val vc2 = VerifiableCredential.create(
+        type = "DateOfBirth",
+        issuer = issuerDid.uri,
+        subject = holderDid.uri,
+        data = DateOfBirth(dateOfBirth = "12/12/2012")
+      )
+      val vcJwt2 = vc2.sign(issuerDid)
+
+      val presentationSubmission = PresentationExchange.createPresentationFromCredentials(listOf(vcJwt2, vcJwt1), pd)
+
+      assertEquals(1, presentationSubmission.descriptorMap.size)
+      assertEquals("$.verifiableCredential[0]", presentationSubmission.descriptorMap[0].path)
+    }
+  }
 }