1 files changed, 63 insertions, 0 deletions

diff --git a/language-web/src/main/java/tools/refinery/language/web/xtext/servlet/SimpleServiceContext.java b/language-web/src/main/java/tools/refinery/language/web/xtext/servlet/SimpleServiceContext.java
new file mode 100644
index 00000000..945d5db0
--- /dev/null
+++ b/language-web/src/main/java/tools/refinery/language/web/xtext/servlet/SimpleServiceContext.java
@@ -0,0 +1,63 @@
+package tools.refinery.language.web.xtext.servlet;
+
+import java.util.Map;
+import java.util.Set;
+
+import org.eclipse.xtext.web.server.IServiceContext;
+import org.eclipse.xtext.web.server.ISession;
+import org.eclipse.xtext.web.server.InvalidRequestException;
+
+import com.google.common.collect.ImmutableMap;
+import com.google.common.collect.ImmutableSet;
+
+record SimpleServiceContext(ISession session, Map<String, String> parameters) implements IServiceContext {
+
+        public static final String RESOURCE_NAME_PARAMETER = "resource";
+
+        public static final String CONTENT_TYPE_PARAMETER = "contentType";
+
+        public static final String STATE_ID_PARAMETER = "requiredStateId";
+
+        @Override
+        public Set<String> getParameterKeys() {
+                return ImmutableSet.copyOf(parameters.keySet());
+        }
+
+        @Override
+        public String getParameter(String key) {
+                return parameters.get(key);
+        }
+
+        @Override
+        public ISession getSession() {
+                return session;
+        }
+
+        public static IServiceContext ofTransaction(ISession session, XtextWebSocketRequest request, String stateId,
+                        int index) {
+                var parameters = request.getRequestData().get(index);
+                checkParameters(parameters, RESOURCE_NAME_PARAMETER);
+                checkParameters(parameters, CONTENT_TYPE_PARAMETER);
+                checkParameters(parameters, STATE_ID_PARAMETER);
+                var builder = ImmutableMap.<String, String>builder();
+                builder.putAll(parameters);
+                if (request.getResourceName() != null) {
+                        builder.put(RESOURCE_NAME_PARAMETER, request.getResourceName());
+                }
+                if (request.getContentType() != null) {
+                        builder.put(CONTENT_TYPE_PARAMETER, request.getContentType());
+                }
+                if (stateId != null) {
+                        builder.put(STATE_ID_PARAMETER, stateId);
+                }
+                var allParameters = builder.build();
+                return new SimpleServiceContext(session, allParameters);
+        }
+
+        private static void checkParameters(Map<String, String> parameters, String perTransactionParameter) {
+                if (parameters.containsKey(perTransactionParameter)) {
+                        throw new InvalidRequestException.InvalidParametersException(
+                                        "Parameters map must not contain '" + perTransactionParameter + "' parameter.");
+                }
+        }
+}