code.dwrz.net

visitor.go (6909B)

---

 package ini
 
 import (
 	"fmt"
 	"sort"
 	"strings"
 )
 
 // Visitor is an interface used by walkers that will
 // traverse an array of ASTs.
 type Visitor interface {
 	VisitExpr(AST) error
 	VisitStatement(AST) error
 }
 
 // DefaultVisitor is used to visit statements and expressions
 // and ensure that they are both of the correct format.
 // In addition, upon visiting this will build sections and populate
 // the Sections field which can be used to retrieve profile
 // configuration.
 type DefaultVisitor struct {
 
 	// scope is the profile which is being visited
 	scope string
 
 	// path is the file path which the visitor is visiting
 	path string
 
 	// Sections defines list of the profile section
 	Sections Sections
 }
 
 // NewDefaultVisitor returns a DefaultVisitor. It takes in a filepath
 // which points to the file it is visiting.
 func NewDefaultVisitor(filepath string) *DefaultVisitor {
 	return &DefaultVisitor{
 		Sections: Sections{
 			container: map[string]Section{},
 		},
 		path: filepath,
 	}
 }
 
 // VisitExpr visits expressions...
 func (v *DefaultVisitor) VisitExpr(expr AST) error {
 	t := v.Sections.container[v.scope]
 	if t.values == nil {
 		t.values = values{}
 	}
 	if t.SourceFile == nil {
 		t.SourceFile = make(map[string]string, 0)
 	}
 
 	switch expr.Kind {
 	case ASTKindExprStatement:
 		opExpr := expr.GetRoot()
 		switch opExpr.Kind {
 		case ASTKindEqualExpr:
 			children := opExpr.GetChildren()
 			if len(children) <= 1 {
 				return NewParseError("unexpected token type")
 			}
 
 			rhs := children[1]
 
 			// The right-hand value side the equality expression is allowed to contain '[', ']', ':', '=' in the values.
 			// If the token is not either a literal or one of the token types that identifies those four additional
 			// tokens then error.
 			if !(rhs.Root.Type() == TokenLit || rhs.Root.Type() == TokenOp || rhs.Root.Type() == TokenSep) {
 				return NewParseError("unexpected token type")
 			}
 
 			key := EqualExprKey(opExpr)
 			val, err := newValue(rhs.Root.ValueType, rhs.Root.base, rhs.Root.Raw())
 			if err != nil {
 				return err
 			}
 
 			// lower case key to standardize
 			k := strings.ToLower(key)
 
 			// identify if the section already had this key, append log on section
 			if t.Has(k) {
 				t.Logs = append(t.Logs,
 					fmt.Sprintf("For profile: %v, overriding %v value, "+
 						"with a %v value found in a duplicate profile defined later in the same file %v. \n",
 						t.Name, k, k, v.path))
 			}
 
 			// assign the value
 			t.values[k] = val
 			// update the source file path for region
 			t.SourceFile[k] = v.path
 		default:
 			return NewParseError(fmt.Sprintf("unsupported expression %v", expr))
 		}
 	default:
 		return NewParseError(fmt.Sprintf("unsupported expression %v", expr))
 	}
 
 	v.Sections.container[v.scope] = t
 	return nil
 }
 
 // VisitStatement visits statements...
 func (v *DefaultVisitor) VisitStatement(stmt AST) error {
 	switch stmt.Kind {
 	case ASTKindCompletedSectionStatement:
 		child := stmt.GetRoot()
 		if child.Kind != ASTKindSectionStatement {
 			return NewParseError(fmt.Sprintf("unsupported child statement: %T", child))
 		}
 
 		name := string(child.Root.Raw())
 
 		// trim start and end space
 		name = strings.TrimSpace(name)
 
 		// if has prefix "profile " + [ws+] + "profile-name",
 		// we standardize by removing the [ws+] between prefix and profile-name.
 		if strings.HasPrefix(name, "profile ") {
 			names := strings.SplitN(name, " ", 2)
 			name = names[0] + " " + strings.TrimLeft(names[1], " ")
 		}
 
 		// attach profile name on section
 		if !v.Sections.HasSection(name) {
 			v.Sections.container[name] = NewSection(name)
 		}
 		v.scope = name
 	default:
 		return NewParseError(fmt.Sprintf("unsupported statement: %s", stmt.Kind))
 	}
 
 	return nil
 }
 
 // Sections is a map of Section structures that represent
 // a configuration.
 type Sections struct {
 	container map[string]Section
 }
 
 // NewSections returns empty ini Sections
 func NewSections() Sections {
 	return Sections{
 		container: make(map[string]Section, 0),
 	}
 }
 
 // GetSection will return section p. If section p does not exist,
 // false will be returned in the second parameter.
 func (t Sections) GetSection(p string) (Section, bool) {
 	v, ok := t.container[p]
 	return v, ok
 }
 
 // HasSection denotes if Sections consist of a section with
 // provided name.
 func (t Sections) HasSection(p string) bool {
 	_, ok := t.container[p]
 	return ok
 }
 
 // SetSection sets a section value for provided section name.
 func (t Sections) SetSection(p string, v Section) Sections {
 	t.container[p] = v
 	return t
 }
 
 // DeleteSection deletes a section entry/value for provided section name./
 func (t Sections) DeleteSection(p string) {
 	delete(t.container, p)
 }
 
 // values represents a map of union values.
 type values map[string]Value
 
 // List will return a list of all sections that were successfully
 // parsed.
 func (t Sections) List() []string {
 	keys := make([]string, len(t.container))
 	i := 0
 	for k := range t.container {
 		keys[i] = k
 		i++
 	}
 
 	sort.Strings(keys)
 	return keys
 }
 
 // Section contains a name and values. This represent
 // a sectioned entry in a configuration file.
 type Section struct {
 	// Name is the Section profile name
 	Name string
 
 	// values are the values within parsed profile
 	values values
 
 	// Errors is the list of errors
 	Errors []error
 
 	// Logs is the list of logs
 	Logs []string
 
 	// SourceFile is the INI Source file from where this section
 	// was retrieved. They key is the property, value is the
 	// source file the property was retrieved from.
 	SourceFile map[string]string
 }
 
 // NewSection returns an initialize section for the name
 func NewSection(name string) Section {
 	return Section{
 		Name:       name,
 		values:     values{},
 		SourceFile: map[string]string{},
 	}
 }
 
 // UpdateSourceFile updates source file for a property to provided filepath.
 func (t Section) UpdateSourceFile(property string, filepath string) {
 	t.SourceFile[property] = filepath
 }
 
 // UpdateValue updates value for a provided key with provided value
 func (t Section) UpdateValue(k string, v Value) error {
 	t.values[k] = v
 	return nil
 }
 
 // Has will return whether or not an entry exists in a given section
 func (t Section) Has(k string) bool {
 	_, ok := t.values[k]
 	return ok
 }
 
 // ValueType will returned what type the union is set to. If
 // k was not found, the NoneType will be returned.
 func (t Section) ValueType(k string) (ValueType, bool) {
 	v, ok := t.values[k]
 	return v.Type, ok
 }
 
 // Bool returns a bool value at k
 func (t Section) Bool(k string) bool {
 	return t.values[k].BoolValue()
 }
 
 // Int returns an integer value at k
 func (t Section) Int(k string) int64 {
 	return t.values[k].IntValue()
 }
 
 // Float64 returns a float value at k
 func (t Section) Float64(k string) float64 {
 	return t.values[k].FloatValue()
 }
 
 // String returns the string value at k
 func (t Section) String(k string) string {
 	_, ok := t.values[k]
 	if !ok {
 		return ""
 	}
 	return t.values[k].StringValue()
 }