Removed attachment demo.

Added ApiUtils - a library for managing api lifecycles with less boilerplate.

Added default values to http api and improved the api utils.

Fixed spacing and comments.

Removed withName and added a bad request response to handle error cases.

Replaced use of 400 error with a 404 and error message as per HTTP spec.

core/build.gradle

@@ -85,6 +85,9 @@ dependencies {
 
     // JPA 2.1 annotations.
     compile "org.hibernate.javax.persistence:hibernate-jpa-2.1-api:1.0.0.Final"
+
+    // RS API: Response type and codes for ApiUtils.
+    compile "javax.ws.rs:javax.ws.rs-api:2.0"
 }
 
 publishing {

core/src/main/kotlin/com/r3corda/core/utilities/ApiUtils.kt

@@ -0,0 +1,27 @@
+package com.r3corda.core.utilities
+
+import com.r3corda.core.crypto.Party
+import com.r3corda.core.crypto.parsePublicKeyBase58
+import com.r3corda.core.node.ServiceHub
+import javax.ws.rs.core.Response
+
+/**
+ * Utility functions to reduce boilerplate when developing HTTP APIs
+ */
+class ApiUtils(val services: ServiceHub) {
+    private val defaultNotFound = { msg: String -> Response.status(Response.Status.NOT_FOUND).entity(msg).build() }
+
+    /**
+     * Get a party and then execute the passed function with the party public key as a parameter.
+     * Usage: withParty(key) { doSomethingWith(it) }
+     */
+    fun withParty(partyKeyStr: String, notFound: (String) -> Response = defaultNotFound, found: (Party) -> Response): Response {
+        return try {
+            val partyKey = parsePublicKeyBase58(partyKeyStr)
+            val party = services.identityService.partyFromKey(partyKey)
+            if(party == null) notFound("Unknown party") else found(party)
+        } catch (e: IllegalArgumentException) {
+            notFound("Invalid base58 key passed for party key")
+        }
+    }
+}

test-utils/src/main/kotlin/com/r3corda/testing/http/HttpApi.kt

@@ -5,8 +5,8 @@ import com.google.common.net.HostAndPort
 import java.net.URL
 
 class HttpApi(val root: URL) {
-    fun putJson(path: String, data: Any) = HttpUtils.putJson(URL(root, path), toJson(data))
-    fun postJson(path: String, data: Any) = HttpUtils.postJson(URL(root, path), toJson(data))
+    fun putJson(path: String, data: Any = Unit) = HttpUtils.putJson(URL(root, path), toJson(data))
+    fun postJson(path: String, data: Any = Unit) = HttpUtils.postJson(URL(root, path), toJson(data))
 
     private fun toJson(any: Any) = ObjectMapper().writeValueAsString(any)