Allow filters to be set in init(); Add ability to set a filter from string directly

Author: aalkin

Framework/Core/include/Framework/AnalysisTask.h

@@ -574,6 +574,11 @@ DataProcessorSpec adaptAnalysisTask(ConfigContext const& ctx, Args&&... args)
 
     callbacks.set<CallbackService::Id::EndOfStream>(eoscb);
 
+    /// call the task's init() function first as it may manipulate the task's elements
+    if constexpr (requires { task->init(ic); }) {
+      task->init(ic);
+    }
+
     /// update configurables in filters and partitions
     homogeneous_apply_refs(
       [&ic](auto& element) -> bool { return analysis_task_parsers::updatePlaceholders(ic, element); },
@@ -584,10 +589,6 @@ DataProcessorSpec adaptAnalysisTask(ConfigContext const& ctx, Args&&... args)
     },
                            *task.get());
 
-    if constexpr (requires { task->init(ic); }) {
-      task->init(ic);
-    }
-
     /// parse process functions to enable requested grouping caches - note that at this state process configurables have their final values
     if constexpr (requires { &T::process; }) {
       AnalysisDataProcessorBuilder::cacheFromArgs(&T::process, true, bindingsKeys, bindingsKeysUnsorted);

Framework/Core/include/Framework/Expressions.h

@@ -610,15 +610,29 @@ struct Filter {
     (void)designateSubtrees(node.get());
   }
 
+  Filter(std::string const& input_) : input{input_} {}
+
   Filter& operator=(Filter&& other) noexcept
   {
     node = std::move(other.node);
+    input = std::move(other.input);
+    return *this;
+  }
+
+  Filter& operator=(std::string const& input_)
+  {
+    input = input_;
+    if (node != nullptr) {
+      node = nullptr;
+    }
     return *this;
   }
 
   std::unique_ptr<Node> node = nullptr;
+  std::string input;
 
   size_t designateSubtrees(Node* node, size_t index = 0);
+  void parse();
 };
 
 template <typename T>

Framework/Core/src/Expressions.cxx

@@ -152,6 +152,12 @@ size_t Filter::designateSubtrees(Node* node, size_t index)
   return index;
 }
 
+void Filter::parse()
+{
+  node = std::make_unique<Node>(Parser::parse(input));
+  (void)designateSubtrees(node.get());
+}
+
 template <typename T>
 constexpr inline auto makeDatum(T const&)
 {
@@ -252,6 +258,9 @@ std::ostream& operator<<(std::ostream& os, DatumSpec const& spec)
 
 void updatePlaceholders(Filter& filter, InitContext& context)
 {
+  if (filter.node == nullptr && !filter.input.empty()) {
+    filter.parse();
+  }
   expressions::walk(filter.node.get(), [&](Node* node) {
     if (node->self.index() == 3) {
       std::get_if<3>(&node->self)->reset(context);