server: fix usernameSignature generation

it/runtime-v2/src/test/java/com/walmartlabs/concord/it/runtime/v2/ConcordConfiguration.java

@@ -27,6 +27,9 @@
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
+import java.security.KeyPair;
+import java.security.KeyPairGenerator;
+import java.util.Base64;
 
 public final class ConcordConfiguration {
 
@@ -44,6 +47,8 @@ public static Path sharedDir() {
                 throw new RuntimeException(e);
             }
         }
+
+        writePrivateKey(sharedDir.resolve("signing.pem"));
     }
 
     public static ConcordRule configure() {
@@ -66,6 +71,9 @@ public static ConcordRule configure() {
                                 pollDelay = "250 milliseconds"
                             }
                         }
+                        process {
+                            signingKeyPath = "%%sharedDir%%/signing.pem"
+                        }
                     }
                     concord-agent {
                         dependencyResolveTimeout = "30 seconds"
@@ -75,7 +83,7 @@ public static ConcordRule configure() {
                             enabled = true
                         }
                     }
-                    """);
+                    """.replaceAll("%%sharedDir%%", sharedDir().toString()));
 
         boolean localMode = Boolean.parseBoolean(System.getProperty("it.local.mode"));
         if (localMode) {
@@ -106,6 +114,23 @@ public static String getServerUrlForAgent(ConcordRule concord) {
         }
     }
 
+    private static Path writePrivateKey(Path targetFile) {
+        try {
+            return Files.writeString(targetFile, generatePkcs8PemPrivateKey());
+        } catch (Exception e) {
+            throw new IllegalStateException("Error writing server username signing key.", e);
+        }
+    }
+
+    private static String generatePkcs8PemPrivateKey() throws Exception {
+        KeyPairGenerator keyGen = KeyPairGenerator.getInstance("RSA");
+        keyGen.initialize(2048);
+        KeyPair pair = keyGen.generateKeyPair();
+        byte[] pkcs8 = pair.getPrivate().getEncoded();
+        String base64 = Base64.getMimeEncoder(64, "\n".getBytes()).encodeToString(pkcs8);
+        return "-----BEGIN PRIVATE KEY-----\n" + base64 + "\n-----END PRIVATE KEY-----";
+    }
+
     private ConcordConfiguration() {
     }
 }

it/runtime-v2/src/test/java/com/walmartlabs/concord/it/runtime/v2/ProcessIT.java

@@ -61,6 +61,23 @@ public void testArgs() throws Exception {
         proc.assertLog(".*Hello, Concord!.*");
     }
 
+    /**
+     * Username signature generation.
+     */
+    @Test
+    public void testUsernameSignature() throws Exception {
+        Payload payload = new Payload()
+                .archive(resource("usernameSignature"));
+
+        ConcordProcess proc = concord.processes().start(payload);
+        expectStatus(proc, ProcessEntry.StatusEnum.FINISHED);
+
+        // ---
+
+        proc.assertNoLog(".*signature: null.*");
+        proc.assertLog(".*signature: (?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/]{2}==|[A-Za-z0-9+/]{3}=)?\\..*");
+    }
+
     /**
      * Groovy script execution.
      */

it/runtime-v2/src/test/resources/com/walmartlabs/concord/it/runtime/v2/usernameSignature/concord.yml

@@ -0,0 +1,6 @@
+configuration:
+  runtime: "concord-v2"
+
+flows:
+  default:
+    - log: "signature: ${initiator.usernameSignature == null ? 'null' : initiator.usernameSignature}."

server/impl/src/main/java/com/walmartlabs/concord/server/process/pipelines/processors/UserInfoProcessor.java

@@ -21,8 +21,6 @@
  */
 
 import com.fasterxml.jackson.databind.ObjectMapper;
-import com.fasterxml.jackson.databind.node.ObjectNode;
-import com.fasterxml.jackson.databind.node.TextNode;
 import com.walmartlabs.concord.server.process.Payload;
 import com.walmartlabs.concord.server.process.pipelines.processors.signing.Signing;
 import com.walmartlabs.concord.server.sdk.ConcordApplicationException;
@@ -60,11 +58,14 @@ public UserInfoProcessor(String key,
     public Payload process(Chain chain, Payload payload) {
         var info = userManager.getCurrentUserInfo();
 
-        var result = objectMapper.convertValue(info, ObjectNode.class);
         if (signing.isEnabled()) {
-            Optional.ofNullable(info.username())
-                    .map(this::sign)
-                    .ifPresent(signature -> result.set("usernameSignature", signature));
+            var signature = Optional.ofNullable(info.username())
+                    .map(this::sign);
+
+            info = signature.isEmpty() ? info : UserInfoProvider.UserInfo.builder()
+                    .from(info)
+                    .usernameSignature(signature.get())
+                    .build();
         }
 
         Map<String, UserInfoProvider.UserInfo> m = new HashMap<>();
@@ -75,9 +76,9 @@ public Payload process(Chain chain, Payload payload) {
         return chain.process(payload);
     }
 
-    private TextNode sign(String username) {
+    private String sign(String username) {
         try {
-            return TextNode.valueOf(signing.sign(username));
+            return signing.sign(username);
         } catch (Exception e) {
             throw new ConcordApplicationException("Error while singing process data: " + e.getMessage(), e);
         }

server/impl/src/main/java/com/walmartlabs/concord/server/user/UserInfoProvider.java

@@ -77,5 +77,8 @@ static ImmutableUserInfo.Builder builder() {
 
         @Nullable
         Map<String, Object> attributes();
+
+        @Nullable
+        String usernameSignature();
     }
 }