_future

Former-commit-id: 06ad874613c270383be5a7355cbb23a2dcf7a903

_future/macros.go

@@ -21,3 +21,20 @@ Of course no breaking-changes to the user's workflow.
 I should not and not need to touch the existing router adaptors.
 
 */
+
+/* 23 March 2017
+Essentially almost finish, on "dirty" code:
+- we can define custom macros, custom validators per custom macro or to all of the available macros,
+- parse the macro and macro funcs to iris.HandlerFunc and passed as middleware
+- use reflection to add custom function signature without need to convert and check for arguments length
+(same performance as with the 'hard-manual' way because the func which does all these checks is executed on boot time)
+
+Todo:
+- Make this new syntax compatible with the already router adaptors (can be done easy)
+- We need to clean the code and think a way to adapt that to Iris in order to be
+easy-to-use while in the same time provide the necessary api for advanced use cases.
+
+
+I should also think if this feature worths the time to be extended into
+a complete interpreter(with tokens, lexers, parsers and AST) and name it 'iel/Iris Expression Language' which could be used everywhere in the framework.
+*/

_future/macros_test.go

@@ -47,6 +47,8 @@ func link(path string, mac _macros) iris.HandlerFunc {
 	if err != nil {
 		panic(err)
 	}
+
+	// println(tmpl.Params[0].Param.FailStatusCode)
 	// link the path,  based on its template with a macro
 	// and return a new compiled macro or a list of iris handlers
 	// in order to be prepended on the original route or make a different function for that?
@@ -334,8 +336,8 @@ func TestMacros(t *testing.T) {
 	// when string macro is used:
 	addMacroFunc("string", "contains", macroFuncFrom(func(text string) _macrofn {
 		return func(paramValue string) bool {
-			println("from string:contains instead of any:string")
-			println("'" + text + "' vs '" + paramValue + "'")
+			// println("from string:contains instead of any:string")
+			// println("'" + text + "' vs '" + paramValue + "'")
 
 			return strings.Contains(paramValue, text)
 		}

_future/param_parser.go

@@ -39,12 +39,44 @@ const (
 	FuncEnd            = ')'
 	FuncParamSeperator = ','
 	FailSeparator      = '!'
-	ORSymbol           = '|'
-	ANDSymbol          = '&'
 )
 
 const DefaultFailStatusCode = 404
 
+type CursorState int
+
+func (cs *CursorState) Is(s CursorState) bool {
+	c := *cs
+	if c == s {
+		switch s {
+		case CursorStateNone:
+			*cs = CursorStateStarted
+		case CursorStateStarted:
+			*cs = CursorStatePending
+		case CursorStatePending:
+			*cs = CursorStateRecording
+		case CursorStateRecording:
+			*cs = CursorStateStarted
+		}
+		return true
+	}
+	return false
+}
+
+// we use that to set a value of each "state".
+// because macro's function's arguments can accepts space and regex with any character
+const (
+	// no : is found yet
+	CursorStateNone CursorState = iota
+	// macro name and first expression guess parsed
+	// and we' ready to walk forward
+	CursorStateStarted
+	// after space, waiting for a macro func begin or !+fail_status_code
+	CursorStatePending
+	// inside the macro func, after the opening parenthesis
+	CursorStateRecording
+)
+
 // Parse i.e:
 // id:int range(1,5) otherFunc(3) !404
 //
@@ -72,18 +104,15 @@ func ParseParam(source string) (*ParamTmpl, error) {
 	// id:int range(1,5)
 	// id:int min(1) max(5)
 	// id:int range(1,5)!404 or !404, space doesn't matters on fail error code.
+	// cursor := 0
+	state := CursorStateNone
 	cursor := 0
-	// waitForFunc setted to true when we validate that we have macro's functions
-	// so we can check for parenthesis.
-	// We need that check because the user may add a regexp with parenthesis.
-	// Although this will not be recommended, user is better to create a macro for its regexp
-	// in order to use it everywhere and reduce code duplication.
-	waitForFunc := false
-	// when inside macro func we don't need to check for anything else, because it could
-	// break the tmpl, i.e FuncSeperator (space) if "contains( )".
-	insideFunc := false
 	for i := 0; i < len(source); i++ {
-		if source[i] == ParamNameSeperator {
+		// TODO: find a better way instead of introducing variables like waitForFunc, insideFunc,
+		// one way is to move the functions with the reverse order but this can fix the problem for now
+		// later it will introduce new bugs, we can find a better static way to check these things, tomorrow.
+		// :int ...
+		if source[i] == ParamNameSeperator && state.Is(CursorStateNone) {
 			if i+1 >= len(source) {
 				return nil, fmt.Errorf("missing marco or raw expression after seperator, on source '%s'", source)
 			}
@@ -100,40 +129,34 @@ func ParseParam(source string) (*ParamTmpl, error) {
 			//  I think to do and is working).
 			t.Macro = MacroTmpl{Name: t.Expression}
 
-			// cursor knows the last known(parsed) char position.
 			cursor = i + 1
 			continue
 		}
-		// TODO: find a better way instead of introducing variables like waitForFunc, insideFunc,
-		// one way is to move the functions with the reverse order but this can fix the problem for now
-		// later it will introduce new bugs, we can find a better static way to check these things, tomorrow.
 
-		// int ...
-		if !waitForFunc && source[i] == FuncSeperator {
+		if source[i] == FuncSeperator && state.Is(CursorStateStarted) {
 			// take the left part: int if it's the first
 			// space after the param name
 			if t.Macro.Name == t.Expression {
 				t.Macro.Name = source[cursor:i]
 			} // else we have one or more functions, skip.
-			waitForFunc = true
 			cursor = i + 1
 			continue
 		}
+
 		// if not inside a func body
 		//         the cursor is a point which can receive a func
 		//         starts with (
-		if !insideFunc && waitForFunc && source[i] == FuncStart {
-			insideFunc = true
+		if source[i] == FuncStart && state.Is(CursorStatePending) {
 			// take the left part: range
 			funcName := source[cursor:i]
 			t.Macro.Funcs = append(t.Macro.Funcs, MacroFuncTmpl{Name: funcName})
-
 			cursor = i + 1
 			continue
 		}
+
 		// 1,5)
 		// we are inside func and )
-		if insideFunc && source[i] == FuncEnd {
+		if source[i] == FuncEnd && state.Is(CursorStateRecording) {
 			// check if we have end parenthesis but not start
 			if len(t.Macro.Funcs) == 0 {
 				return nil, fmt.Errorf("missing start macro's '%s' function, on source '%s'", t.Macro.Name, source)
@@ -141,25 +164,19 @@ func ParseParam(source string) (*ParamTmpl, error) {
 
 			// take the left part, between Start and End: 1,5
 			funcParamsStr := source[cursor:i]
-			println("param_parser.go:41: '" + funcParamsStr + "'")
 
 			funcParams := strings.SplitN(funcParamsStr, string(FuncParamSeperator), -1)
 			t.Macro.Funcs[len(t.Macro.Funcs)-1].Params = funcParams
-
 			cursor = i + 1
-
-			insideFunc = false  // ignore ')' until new '('
-			waitForFunc = false // wait for the next space to not ignore '('
 			continue
 		}
 
-		if source[i] == FailSeparator {
+		if source[i] == FailSeparator && (state.Is(CursorStateStarted) || state.Is(CursorStatePending)) {
 			// it should be the last element
 			// so no problem if we set the cursor here and work with that
 			// we will not need that later.
-			cursor = i + 1
-
-			if cursor >= len(source) {
+			cursor += 1
+			if i+1 >= len(source) {
 				return nil, fmt.Errorf("missing fail status code after '%q', on source '%s'", FailSeparator, source)
 			}
 
@@ -171,7 +188,7 @@ func ParseParam(source string) (*ParamTmpl, error) {
 
 			t.FailStatusCode = failCode
 
-			continue
+			break
 		}
 
 	}

_future/param_parser_test.go

@@ -51,9 +51,10 @@ func TestParamParser(t *testing.T) {
 
 	// id:int
 	expected := &ParamTmpl{
-		Name:       "id",
-		Expression: "int",
-		Macro:      MacroTmpl{Name: "int"},
+		Name:           "id",
+		Expression:     "int",
+		FailStatusCode: 404,
+		Macro:          MacroTmpl{Name: "int"},
 	}
 	source := expected.Name + string(ParamNameSeperator) + expected.Expression
 	if err := testParamParser(expected.Name+":"+expected.Expression, expected); err != nil {
@@ -63,8 +64,9 @@ func TestParamParser(t *testing.T) {
 
 	// id:int range(1,5)
 	expected = &ParamTmpl{
-		Name:       "id",
-		Expression: "int range(1,5)",
+		Name:           "id",
+		Expression:     "int range(1,5)",
+		FailStatusCode: 404,
 		Macro: MacroTmpl{Name: "int",
 			Funcs: []MacroFuncTmpl{
 				MacroFuncTmpl{Name: "range", Params: []string{"1", "5"}},
@@ -79,8 +81,9 @@ func TestParamParser(t *testing.T) {
 
 	// id:int min(1) max(5)
 	expected = &ParamTmpl{
-		Name:       "id",
-		Expression: "int min(1) max(5)",
+		Name:           "id",
+		Expression:     "int min(1) max(5)",
+		FailStatusCode: 404,
 		Macro: MacroTmpl{Name: "int",
 			Funcs: []MacroFuncTmpl{
 				MacroFuncTmpl{Name: "min", Params: []string{"1"}},