Brought back CredentialsSuppliers

Author: artem-v

services-api/src/main/java/io/scalecube/services/auth/CredentialsSuppliers.java

@@ -0,0 +1,24 @@
+package io.scalecube.services.auth;
+
+/**
+ * Factory for {@link CredentialsSupplier} objects. Responsible for producing {@link
+ * CredentialsSupplier} for service role that is known upfront.
+ */
+public class CredentialsSuppliers {
+
+  private final CredentialsSupplier credentialsSupplier;
+
+  public CredentialsSuppliers(CredentialsSupplier credentialsSupplier) {
+    this.credentialsSupplier = credentialsSupplier;
+  }
+
+  /**
+   * Returns {@link CredentialsSupplier} instance per given {@code serviceRole}.
+   *
+   * @param serviceRole serviceRole
+   * @return {@link CredentialsSupplier} instance
+   */
+  public CredentialsSupplier forServiceRole(String serviceRole) {
+    return (service, allowedRoles) -> credentialsSupplier.credentials(service, serviceRole);
+  }
+}