Add $schema prop to drc/erc

eeschema/erc_report.cpp

@@ -115,6 +115,7 @@ bool ERC_REPORT::WriteJsonReport( const wxString& aFullFileName )
 
     RC_JSON::ERC_REPORT reportHead;
     wxFileName          fn( m_sch->GetFileName() );
+    reportHead.$schema = "https://schemas.kicad.org/erc.v1.json";
     reportHead.source = fn.GetFullName();
     reportHead.date = GetISO8601CurrentDateTime();
     reportHead.kicad_version = GetMajorMinorPatchVersion();

include/rc_json_schema.h

@@ -78,6 +78,7 @@ inline void from_json( const nlohmann::json& aJson, VIOLATION& aViolation )
 
 struct REPORT_BASE
 {
+    wxString $schema;
     wxString source;
     wxString date;
     wxString kicad_version;
@@ -94,7 +95,7 @@ struct DRC_REPORT : REPORT_BASE
     std::vector<VIOLATION>                 schematic_parity;
 };
 
-NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE( DRC_REPORT, source, date, kicad_version, violations,
+NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE( DRC_REPORT, $schema, source, date, kicad_version, violations,
                                     unconnected_items, schematic_parity, coordinate_units )
 
 struct ERC_SHEET
@@ -113,7 +114,7 @@ struct ERC_REPORT : REPORT_BASE
     std::vector<ERC_SHEET> sheets;
 };
 
-NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE( ERC_REPORT, source, date, kicad_version, sheets,
+NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE( ERC_REPORT, $schema, source, date, kicad_version, sheets,
                                     coordinate_units )
 
 } // namespace RC_JSON

pcbnew/drc/drc_report.cpp

@@ -123,6 +123,7 @@ bool DRC_REPORT::WriteJsonReport( const wxString& aFullFileName )
     RC_JSON::DRC_REPORT reportHead;
 
     wxFileName fn( m_board->GetFileName() );
+    reportHead.$schema = "https://schemas.kicad.org/drc.v1.json";
     reportHead.source = fn.GetFullName();
     reportHead.date = GetISO8601CurrentDateTime();
     reportHead.kicad_version = GetMajorMinorPatchVersion();

resources/schemas/drc.v1.json

@@ -6,6 +6,10 @@
   "type": "object",
   "additionalProperties": false,
   "properties": {
+    "$schema": {
+      "type": "string",
+      "description": "JSON schema reference"
+    },
     "source": {
       "type": "string",
       "description": "Source file path"

resources/schemas/erc.v1.json

@@ -6,6 +6,10 @@
   "type": "object",
   "additionalProperties": false,
   "properties": {
+    "$schema": {
+      "type": "string",
+      "description": "JSON schema reference"
+    },
     "source": {
       "type": "string",
       "description": "Source file path"