# HG changeset patch
# User jbe
# Date 1447517223 -3600
# Node ID 4bcedf32b0890f505ec2196264ec1f21a4568c95
# Parent  fb98b17056e5a255a1003f1038a3dfe8d38aca12
Allow direct (proxy) access to fields of JSON object in a special column (set in the model) (write access not implemented yet)

diff -r fb98b17056e5 -r 4bcedf32b089 libraries/mondelefant/mondelefant.lua
--- a/libraries/mondelefant/mondelefant.lua	Sat Nov 14 15:44:53 2015 +0100
+++ b/libraries/mondelefant/mondelefant.lua	Sat Nov 14 17:07:03 2015 +0100
@@ -915,11 +915,22 @@
 
 Primary key of a database class (model). Defaults to "id".
 
+If the primary key is a tuple, then a sequence (table with integer keys mapped to the column names) must be used. If the primary key is contained in a JSON document within a table column, then a special object with the following fields is expected: {json_doc = "column_name", key = "field_name_within_json_object", type = "postgresql_type"}.
+
 --]]--
 class_prototype.primary_key = "id"
 --//--
 
 --[[--
+<db_class>.document_column
+
+Optional column name to redirect key lookups to. This can be used to allow for an easier access to fields of a JSON document.
+
+--]]--
+class_prototype.document_column = nil
+--//--
+
+--[[--
 db_handle =               -- database connection handle used by this class
 <db_class>:get_db_conn()
 
diff -r fb98b17056e5 -r 4bcedf32b089 libraries/mondelefant/mondelefant_native.c
--- a/libraries/mondelefant/mondelefant_native.c	Sat Nov 14 15:44:53 2015 +0100
+++ b/libraries/mondelefant/mondelefant_native.c	Sat Nov 14 17:07:03 2015 +0100
@@ -1490,80 +1490,87 @@
   // different lookup for lists and objects:
   if (result_type && !strcmp(result_type, "object")) {  // object
     lua_settop(L, 3);
-    // try inherited attributes, methods or getter functions:
-    while (lua_toboolean(L, 3)) {
-      lua_getfield(L, 3, "object");  // 4
-      lua_pushvalue(L, 2);  // 5
-      lua_gettable(L, 4);  // 5
-      if (!lua_isnil(L, 5)) return 1;
-      lua_settop(L, 3);
-      lua_getfield(L, 3, "object_get");  // 4
-      lua_pushvalue(L, 2);  // 5
-      lua_gettable(L, 4);  // 5
-      if (lua_toboolean(L, 5)) {
-        lua_pushvalue(L, 1);  // 6
-        lua_call(L, 1, 1);  // 5
+    lua_pushnil(L);
+    lua_insert(L, 3);  // optional document column name on stack position 3
+    // try inherited attributes, methods or getter functions
+    // (and determine optional document column, if existent):
+    while (lua_toboolean(L, 4)) {  // class on stack position 4 (due to insert)
+      lua_getfield(L, 4, "object");  // 5
+      lua_pushvalue(L, 2);  // 6
+      lua_gettable(L, 5);  // 6
+      if (!lua_isnil(L, 6)) return 1;
+      lua_settop(L, 4);
+      lua_getfield(L, 4, "object_get");  // 5
+      lua_pushvalue(L, 2);  // 6
+      lua_gettable(L, 5);  // 6
+      if (lua_toboolean(L, 6)) {
+        lua_pushvalue(L, 1);  // 7
+        lua_call(L, 1, 1);  // 6
         return 1;
       }
-      lua_settop(L, 3);
-      lua_pushliteral(L, "prototype");  // 4
-      lua_rawget(L, 3);  // 4
-      lua_replace(L, 3);
+      lua_settop(L, 4);
+      if (lua_isnil(L, 3)) {
+        lua_getfield(L, 4, "document_column");  // 5
+        lua_replace(L, 3);
+      }
+      lua_pushliteral(L, "prototype");  // 5
+      lua_rawget(L, 4);  // 5
+      lua_replace(L, 4);
     }
-    lua_settop(L, 2);
+    lua_settop(L, 3);
     // try primary keys of referenced objects:
     lua_pushcfunction(L,
       mondelefant_class_get_foreign_key_reference_name
-    );  // 3
-    lua_getfield(L, 1, "_class");  // 4
-    lua_pushvalue(L, 2);  // 5
-    lua_call(L, 2, 1);  // 3
-    if (!lua_isnil(L, 3)) {
-      // reference name at stack position 3
-      lua_pushcfunction(L, mondelefant_class_get_reference);  // 4
-      lua_getfield(L, 1, "_class");  // 5
-      lua_pushvalue(L, 3);  // 6
-      lua_call(L, 2, 1);  // reference info at stack position 4
-      lua_getfield(L, 1, "_ref");  // 5
-      lua_getfield(L, 4, "ref");  // 6
-      lua_gettable(L, 5);  // 6
-      if (!lua_isnil(L, 6)) {
-        if (lua_toboolean(L, 6)) {
-          lua_getfield(L, 4, "that_key");  // 7
-          if (lua_isnil(L, 7)) {
+    );  // 4
+    lua_getfield(L, 1, "_class");  // 5
+    lua_pushvalue(L, 2);  // 6
+    lua_call(L, 2, 1);  // 4
+    if (!lua_isnil(L, 4)) {
+      // reference name at stack position 4
+      lua_pushcfunction(L, mondelefant_class_get_reference);  // 5
+      lua_getfield(L, 1, "_class");  // 6
+      lua_pushvalue(L, 4);  // 7
+      lua_call(L, 2, 1);  // reference info at stack position 5
+      lua_getfield(L, 1, "_ref");  // 6
+      lua_getfield(L, 4, "ref");  // 7
+      lua_gettable(L, 6);  // 7
+      if (!lua_isnil(L, 7)) {
+        if (lua_toboolean(L, 7)) {
+          lua_getfield(L, 5, "that_key");  // 8
+          if (lua_isnil(L, 8)) {
             return luaL_error(L, "Missing 'that_key' entry in model reference.");
           }
-          lua_gettable(L, 6);  // 7
+          lua_gettable(L, 7);  // 8
         } else {
           lua_pushnil(L);
         }
         return 1;
       }
     }
-    lua_settop(L, 2);
+    lua_settop(L, 3);
     // try normal data field info:
-    lua_getfield(L, 1, "_data");  // 3
-    lua_pushvalue(L, 2);  // 4
-    lua_gettable(L, 3);  // 4
-    if (!lua_isnil(L, 4)) return 1;
-    lua_settop(L, 2);
+    lua_getfield(L, 1, "_data");  // 4
+    lua_pushvalue(L, 2);  // 5
+    lua_gettable(L, 4);  // 5
+    if (!lua_isnil(L, 5)) return 1;
+    lua_settop(L, 3);  // TODO: keep _data table on stack
     // try cached referenced object (or cached NULL reference):
-    lua_getfield(L, 1, "_ref");  // 3
-    lua_pushvalue(L, 2);  // 4
-    lua_gettable(L, 3);  // 4
-    if (lua_isboolean(L, 4) && !lua_toboolean(L, 4)) {
+    lua_getfield(L, 1, "_ref");  // 4
+    lua_pushvalue(L, 2);  // 5
+    lua_gettable(L, 4);  // 5
+    if (lua_isboolean(L, 5) && !lua_toboolean(L, 5)) {
       lua_pushnil(L);
       return 1;
-    } else if (!lua_isnil(L, 4)) {
+    } else if (!lua_isnil(L, 5)) {
       return 1;
     }
-    lua_settop(L, 2);
+    lua_settop(L, 3);
     // try to load a referenced object:
-    lua_pushcfunction(L, mondelefant_class_get_reference);  // 3
-    lua_getfield(L, 1, "_class");  // 4
-    lua_pushvalue(L, 2);  // 5
-    lua_call(L, 2, 1);  // 3
-    if (!lua_isnil(L, 3)) {
+    lua_pushcfunction(L, mondelefant_class_get_reference);  // 4
+    lua_getfield(L, 1, "_class");  // 5
+    lua_pushvalue(L, 2);  // 6
+    lua_call(L, 2, 1);  // 4
+    if (!lua_isnil(L, 4)) {
       lua_settop(L, 2);
       lua_getfield(L, 1, "load");  // 3
       lua_pushvalue(L, 1);  // 4 (self)
@@ -1576,6 +1583,18 @@
       if (lua_isboolean(L, 4) && !lua_toboolean(L, 4)) lua_pushnil(L);  // TODO: use special object instead of false
       return 1;
     }
+    lua_settop(L, 3);
+    // try proxy access to document in special column:
+    if (lua_toboolean(L, 3)) {
+      lua_getfield(L, 1, "_data");  // 4  TODO: keep on stack from earlier
+      lua_insert(L, 3);  // column name to stack position 4
+      lua_gettable(L, 3);  // 4
+      if (!lua_isnil(L, 4)) {
+        lua_pushvalue(L, 2);  // 5
+        lua_gettable(L, 4);  // 5
+        if (!lua_isnil(L, 5)) return 1;
+      }
+    }
     return 0;
   } else if (result_type && !strcmp(result_type, "list")) {  // list
     lua_settop(L, 3);