HONEYCOMB-10: jVpp - the new java API. Java code generation

The old japi has two main drawbacks:

* it is not fully generated (requres manual coding for
every new api call that returns data other thanstatus code)

* it is not asynchronous from Java perspective (requires
active wait loops - big overhead due to JNI boundary being
crossed lots of times).

The new api is lightweight (fully generated except for connect,
disconenct and ping) and truly asynchronous (uses callbacks,
utilities that offer java.util.concurrent.Future interface
are also provided).

Change-Id: I531080ef651e8a74f19210490c71d161221ab600
Signed-off-by: Marek Gradzki <mgradzki@cisco.com>
Signed-off-by: Maros Marsalek <mmarsale@cisco.com>
Signed-off-by: Ed Warnicke <eaw@cisco.com>

1 files changed, 184 insertions, 0 deletions

diff --git a/vpp-api/java/jvpp/gen/jvpp_future_facade_gen.py b/vpp-api/java/jvpp/gen/jvpp_future_facade_gen.py
new file mode 100644
index 00000000000..2aae5b8018a
--- /dev/null
+++ b/vpp-api/java/jvpp/gen/jvpp_future_facade_gen.py
@@ -0,0 +1,184 @@
+#!/usr/bin/env python
+#
+# Copyright (c) 2016 Cisco and/or its affiliates.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at:
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import os, util
+from string import Template
+
+import dto_gen
+
+jvpp_facade_callback_template = Template("""
+package $base_package.$future_package;
+
+/**
+ * Async facade callback setting values to future objects
+ */
+public final class FutureJVppFacadeCallback implements $base_package.$callback_package.JVppGlobalCallback {
+
+    private final java.util.Map<java.lang.Integer, java.util.concurrent.CompletableFuture<? extends $base_package.$dto_package.JVppReply<?>>> requests;
+
+    public FutureJVppFacadeCallback(final java.util.Map<java.lang.Integer, java.util.concurrent.CompletableFuture<? extends $base_package.$dto_package.JVppReply<?>>> requestMap) {
+        this.requests = requestMap;
+    }
+
+$methods
+}
+""")
+
+jvpp_facade_callback_method_template = Template("""
+    @Override
+    @SuppressWarnings("unchecked")
+    public void on$callback_dto($base_package.$dto_package.$callback_dto reply) {
+        final java.util.concurrent.CompletableFuture<$base_package.$dto_package.JVppReply<?>> completableFuture;
+
+        synchronized(requests) {
+            completableFuture = (java.util.concurrent.CompletableFuture<$base_package.$dto_package.JVppReply<?>>) requests.get(reply.context);
+        }
+
+        if(completableFuture != null) {
+            if(reply.retval < 0) {
+                completableFuture.completeExceptionally(new Exception("Invocation of " + $base_package.$dto_package.$callback_dto.class
+                    + " failed with value " + reply.retval));
+            } else {
+                completableFuture.complete(reply);
+            }
+
+            synchronized(requests) {
+                requests.remove(reply.context);
+            }
+        }
+    }
+""")
+
+# TODO reuse common parts with generic method callback
+jvpp_facade_control_ping_method_template = Template("""
+    @Override
+    @SuppressWarnings("unchecked")
+    public void on$callback_dto($base_package.$dto_package.$callback_dto reply) {
+        final java.util.concurrent.CompletableFuture<$base_package.$dto_package.JVppReply<?>> completableFuture;
+
+        synchronized(requests) {
+            completableFuture = (java.util.concurrent.CompletableFuture<$base_package.$dto_package.JVppReply<?>>) requests.get(reply.context);
+        }
+
+        if(completableFuture != null) {
+            // Finish dump call
+            if (completableFuture instanceof $base_package.$future_package.FutureJVppFacade.CompletableDumpFuture) {
+                completableFuture.complete((($base_package.$future_package.FutureJVppFacade.CompletableDumpFuture) completableFuture).getReplyDump());
+                // Remove future mapped to dump call context id
+                synchronized(requests) {
+                    requests.remove((($base_package.$future_package.FutureJVppFacade.CompletableDumpFuture) completableFuture).getContextId());
+                }
+            } else {
+                if(reply.retval < 0) {
+                    completableFuture.completeExceptionally(new Exception("Invocation of " + $base_package.$dto_package.$callback_dto.class
+                        + " failed with value " + reply.retval));
+                } else {
+                    completableFuture.complete(reply);
+                }
+            }
+
+            synchronized(requests) {
+                requests.remove(reply.context);
+            }
+        }
+    }
+""")
+
+jvpp_facade_details_callback_method_template = Template("""
+    @Override
+    @SuppressWarnings("unchecked")
+    public void on$callback_dto($base_package.$dto_package.$callback_dto reply) {
+        final FutureJVppFacade.CompletableDumpFuture<$base_package.$dto_package.$callback_dto_reply_dump> completableFuture;
+
+        synchronized(requests) {
+            completableFuture = ($base_package.$future_package.FutureJVppFacade.CompletableDumpFuture<$base_package.$dto_package.$callback_dto_reply_dump>) requests.get(reply.context);
+        }
+
+        if(completableFuture != null) {
+            $base_package.$dto_package.$callback_dto_reply_dump replyDump = completableFuture.getReplyDump();
+            if(replyDump == null) {
+                replyDump = new $base_package.$dto_package.$callback_dto_reply_dump();
+                completableFuture.setReplyDump(replyDump);
+            }
+
+            replyDump.$callback_dto_field.add(reply);
+        }
+    }
+""")
+
+
+def generate_jvpp(func_list, base_package, dto_package, callback_package, future_facade_package):
+    """ Generates JVpp interface and JNI implementation """
+    print "Generating JVpp future facade"
+
+    if not os.path.exists(future_facade_package):
+        raise Exception("%s folder is missing" % future_facade_package)
+
+    callbacks = []
+    for func in func_list:
+
+        if util.is_notification(func['name']) or util.is_ignored(func['name']):
+            # TODO handle notifications
+            continue
+
+        camel_case_name_with_suffix = util.underscore_to_camelcase_upper(func['name'])
+        if not util.is_reply(camel_case_name_with_suffix):
+            continue
+
+        if util.is_details(camel_case_name_with_suffix):
+            camel_case_method_name = util.underscore_to_camelcase(func['name'])
+            camel_case_request_name = get_standard_dump_reply_name(util.underscore_to_camelcase_upper(func['name']),
+                                                                   func['name'])
+            callbacks.append(jvpp_facade_details_callback_method_template.substitute(base_package=base_package,
+                                                                                     dto_package=dto_package,
+                                                                                     callback_dto=camel_case_name_with_suffix,
+                                                                                     callback_dto_field=camel_case_method_name,
+                                                                                     callback_dto_reply_dump=camel_case_request_name + dto_gen.dump_dto_suffix,
+                                                                                     future_package=future_facade_package))
+        else:
+            if util.is_control_ping(camel_case_name_with_suffix):
+                callbacks.append(jvpp_facade_control_ping_method_template.substitute(base_package=base_package,
+                                                                                     dto_package=dto_package,
+                                                                                     callback_dto=camel_case_name_with_suffix,
+                                                                                     future_package=future_facade_package))
+            else:
+                callbacks.append(jvpp_facade_callback_method_template.substitute(base_package=base_package,
+                                                                                 dto_package=dto_package,
+                                                                                 callback_dto=camel_case_name_with_suffix))
+
+    jvpp_file = open(os.path.join(future_facade_package, "FutureJVppFacadeCallback.java"), 'w')
+    jvpp_file.write(jvpp_facade_callback_template.substitute(base_package=base_package,
+                                                             dto_package=dto_package,
+                                                             callback_package=callback_package,
+                                                             methods="".join(callbacks),
+                                                             future_package=future_facade_package))
+    jvpp_file.flush()
+    jvpp_file.close()
+
+
+# Returns request name or special one from unconventional_naming_rep_req map
+def get_standard_dump_reply_name(camel_case_dto_name, func_name):
+    # FIXME this is a hotfix for sub-details callbacks
+    # FIXME also for L2FibTableEntry
+    # It's all because unclear mapping between
+    #  request -> reply,
+    #  dump -> reply, details,
+    #  notification_start -> reply, notifications
+
+    # vpe.api needs to be "standardized" so we can parse the information and create maps before generating java code
+    suffix = func_name.split("_")[-1]
+    return util.underscore_to_camelcase_upper(
+        util.unconventional_naming_rep_req[func_name]) + util.underscore_to_camelcase_upper(suffix) if func_name in util.unconventional_naming_rep_req \
+        else camel_case_dto_name