refactor

persist/string-adapter/adapter.go

@@ -15,87 +15,53 @@
 package stringadapter
 
 import (
-	"bytes"
 	"errors"
 	"strings"
 
 	"github.com/casbin/casbin/v3/model"
 	"github.com/casbin/casbin/v3/persist"
-	"github.com/casbin/casbin/v3/util"
 )
 
-// Adapter is the string adapter for Casbin.
-// It can load policy from string or save policy to string.
-type Adapter struct {
-	lines string
-}
-
-// NewAdapter is the constructor for Adapter.
-func NewAdapter(lines string) *Adapter {
-	return &Adapter{lines: lines}
-}
+// String is the string adapter for Casbin.
+// It can load policy from string.
+type String string
 
-// LoadPolicy loads all policy rules from the storage.
-func (a *Adapter) LoadPolicy(model model.Model) error {
-	if a.lines == "" {
-		return errors.New("invalid lines, lines cannot be empty")
-	}
-
-	rows := strings.Split(a.lines, "\n")
+// LoadPolicy loads all policy rules from the string.
+func (a String) LoadPolicy(model model.Model) error {
+	rows := strings.Split(string(a), "\n")
 	for _, line := range rows {
 		persist.LoadPolicyLine(strings.TrimSpace(line), model)
 	}
 
 	return nil
 }
 
-// SavePolicy saves all policy rules to the storage.
-func (a *Adapter) SavePolicy(model model.Model) error {
-	var tmp bytes.Buffer
-	ptypes := model.GetPtypes("p")
-	for _, ptype := range ptypes {
-		for _, rule := range model.GetPolicy("p", ptype) {
-			tmp.WriteString(ptype + ", ")
-			tmp.WriteString(util.ArrayToString(rule))
-			tmp.WriteString("\n")
-		}
-	}
-
-	ptypes = model.GetPtypes("g")
-	for _, ptype := range ptypes {
-		for _, rule := range model.GetPolicy("g", ptype) {
-			tmp.WriteString(ptype + ", ")
-			tmp.WriteString(util.ArrayToString(rule))
-			tmp.WriteString("\n")
-		}
-	}
-
-	a.lines = strings.TrimRight(tmp.String(), "\n")
-
-	return nil
+// SavePolicy is not supported by this adaptater.
+func (a String) SavePolicy(model model.Model) error {
+	return errors.New("not implemented")
 }
 
-// AddPolicy adds a policy rule to the storage.
-func (a *Adapter) AddPolicy(sec string, ptype string, rule []string) error {
+// AddPolicy is not supported by this adaptater.
+func (a String) AddPolicy(sec string, ptype string, rule []string) error {
 	return errors.New("not implemented")
 }
 
-// AddPolicies adds policy rules to the storage.
-func (a *Adapter) AddPolicies(sec string, ptype string, rules [][]string) error {
+// AddPolicies is not supported by this adaptater.
+func (a String) AddPolicies(sec string, ptype string, rules [][]string) error {
 	return errors.New("not implemented")
 }
 
-// RemovePolicy removes a policy rule from the storage.
-func (a *Adapter) RemovePolicy(sec string, ptype string, rule []string) error {
+// RemovePolicy is not supported by this adaptater.
+func (a String) RemovePolicy(sec string, ptype string, rule []string) error {
 	return errors.New("not implemented")
 }
 
-// RemovePolicies removes policy rules from the storage.
-func (a *Adapter) RemovePolicies(sec string, ptype string, rules [][]string) error {
+// RemovePolicies is not supported by this adaptater.
+func (a String) RemovePolicies(sec string, ptype string, rules [][]string) error {
 	return errors.New("not implemented")
 }
 
-// RemoveFilteredPolicy removes policy rules that match the filter from the storage.
-func (a *Adapter) RemoveFilteredPolicy(sec string, ptype string, fieldIndex int, fieldValues ...string) error {
+// RemoveFilteredPolicy is not supported by this adaptater.
+func (a String) RemoveFilteredPolicy(sec string, ptype string, fieldIndex int, fieldValues ...string) error {
 	return errors.New("not implemented")
 }

persist/string-adapter/adapter_filtered.go

@@ -22,10 +22,10 @@ import (
 	"github.com/casbin/casbin/v3/persist"
 )
 
-// FilteredAdapter is the filtered file adapter for Casbin. It can load policy
-// from file or save policy to file and supports loading of filtered policies.
+// FilteredAdapter is the filtered string adapter for Casbin. It can load policy
+// from string and supports loading of filtered policies.
 type FilteredAdapter struct {
-	*Adapter
+	String
 	filtered bool
 }
 
@@ -37,17 +37,17 @@ type Filter struct {
 }
 
 // NewFilteredAdapter is the constructor for FilteredAdapter.
-func NewFilteredAdapter(filePath string) *FilteredAdapter {
-	a := FilteredAdapter{}
-	a.filtered = true
-	a.Adapter = NewAdapter(filePath)
-	return &a
+func NewFilteredAdapter(policy string) *FilteredAdapter {
+	return &FilteredAdapter{
+		filtered: false,
+		String:   String(policy),
+	}
 }
 
 // LoadPolicy loads all policy rules from the storage.
 func (a *FilteredAdapter) LoadPolicy(model model.Model) error {
 	a.filtered = false
-	return a.Adapter.LoadPolicy(model)
+	return a.String.LoadPolicy(model)
 }
 
 // LoadFilteredPolicy loads only policy rules that match the filter.
@@ -68,7 +68,7 @@ func (a *FilteredAdapter) LoadFilteredPolicy(model model.Model, filter interface
 }
 
 func (a *FilteredAdapter) loadFilteredPolicyFile(model model.Model, filter *Filter, handler func(string, model.Model)) error {
-	rows := strings.Split(a.lines, "\n")
+	rows := strings.Split(string(a.String), "\n")
 	for _, line := range rows {
 		line := strings.TrimSpace(line)
 		if filterLine(line, filter) {
@@ -91,7 +91,7 @@ func (a *FilteredAdapter) SavePolicy(model model.Model) error {
 	if a.filtered {
 		return errors.New("cannot save a filtered policy")
 	}
-	return a.Adapter.SavePolicy(model)
+	return errors.New("not implemented")
 }
 
 func filterLine(line string, filter *Filter) bool {

persist/string-adapter/adapter_test.go

@@ -45,7 +45,7 @@ p, data_group_admin, /admin/*, POST
 p, data_group_admin, /bob_data/*, POST
 g, alice, data_group_admin
 `
-	a := NewAdapter(line)
+	a := String(line)
 	m := model.NewModel()
 	err := m.LoadModelFromText(conf)
 	if err != nil {
@@ -84,7 +84,7 @@ p, data_group_admin, data3, read
 p, data_group_admin, data3, write
 g, alice, data_group_admin
 `
-	a := NewAdapter(line)
+	a := String(line)
 	m := model.NewModel()
 	err := m.LoadModelFromText(conf)
 	if err != nil {