F multi retrieve

Summary

Implements multi-entity retrieval caosdb/customers/lfpb/management#393

See tests in caosdb-cppinttest!4 (merged)

Focus

• Most relevant changes are in include/caosdb/transaction.h and src/caosdb/transaction.cpp.
• New class MultiResultSet represents a result set with multiple entities. Is this a good name?
• New enum TransactionType restricts the kind of sub-transactions (Insert, Delete, Retrieve) which can be added to a transaction.
• Macros are used to check whether InsertEntity, DeleteById or RetrieveById can be called on a transaction (given the TransactionStatus and 'TransactionType`).

Test Environment

Test with server in branch f-grpc-f-multi-retrieve

Check List for the Author

Please, prepare your MR for a review. Be sure to write a summary and a focus and create gitlab comments for the reviewer. They should guide the reviewer through the changes, explain your changes and also point out open questions. For further good practices have a look at our review guidelines

• All automated tests pass
• Reference related Issues
• Up-to-date CHANGELOG.md
• Annotations in code (Gitlab comments)
  • Intent of new code
  • Problems with old code
  • Why this implementation?

Check List for the Reviewer

• I understand the intent of this MR
• All automated tests pass
• Up-to-date CHANGELOG.md
• The test environment setup works and the intended behavior is reproducible in the test environment
• In-code documentation and comments are up-to-date.
• Check: Are there specifications? Are they satisfied?

For further good practices have a look at our review guidelines.

include/caosdb/entity.h

@@ -54,6 +54,8 @@ public:
   }
 
   friend class Entity;
+  friend class Parent;
+  friend class Property;
   friend class Messages;
 
 private:
@@ -74,6 +76,8 @@ public:
   }
 
   friend class Entity;
+  friend class Parent;
+  friend class Property;
 
 private:
   inline Messages() : wrapped(nullptr){};
@@ -135,15 +139,27 @@ public:
   /**
    * Return the error messages of this parent.
    */
-  [[nodiscard]] inline auto GetErrors() const -> const Messages &;
+  [[nodiscard]] inline auto GetErrors() const -> const Messages & {
+    return errors;
+  }
+  [[nodiscard]] inline auto HasErrors() const -> bool {
+    return this->errors.wrapped->size() > 0;
+  }
   /**
    * Return the warning messages of this parent.
    */
-  [[nodiscard]] inline auto GetWarnings() const -> const Messages &;
+  [[nodiscard]] inline auto GetWarnings() const -> const Messages & {
+    return warnings;
+  }
+  [[nodiscard]] inline auto HasWarnings() const -> bool {
+    return this->warnings.wrapped->size() > 0;
+  }
   /**
    * Return the info messages of this parent.
    */
-  [[nodiscard]] inline auto GetInfos() const -> const Messages &;
+  [[nodiscard]] inline auto GetInfos() const -> const Messages & {
+    return infos;
+  }
 
   friend class Entity;
   friend class Parents;
@@ -165,6 +181,9 @@ private:
    * Message which serves as storage backend.
    */
   mutable caosdb::entity::v1alpha1::Parent *wrapped;
+  Messages errors;
+  Messages warnings;
+  Messages infos;
 };
 
 /**
@@ -310,6 +329,9 @@ public:
   [[nodiscard]] inline auto GetUnit() const -> const std::string & {
     return wrapped->unit();
   };
+  [[nodiscard]] inline auto GetValue() const -> const std::string & {
+    return wrapped->value();
+  };
 
   [[nodiscard]] auto GetParents() const -> const Parents &;
   [[nodiscard]] auto GetProperties() const -> const Properties &;
@@ -322,6 +344,9 @@ public:
   [[nodiscard]] auto GetWarnings() const -> const Messages & {
     return warnings;
   }
+  [[nodiscard]] inline auto HasWarnings() const -> bool {
+    return this->warnings.wrapped->size() > 0;
+  }
   [[nodiscard]] auto GetInfos() const -> const Messages & { return infos; }
 
   inline auto ToString() const -> const std::string {
@@ -337,7 +362,6 @@ public:
   auto SetName(const std::string &name) -> void;
   auto SetVersionId(const std::string &id) -> void;
 
-  // TODO(fspreck) ... and also these
   auto SetValue(const std::string &value) -> void;
   auto SetUnit(const std::string &unit) -> void;
   // Currently no references or lists.