Merge pull request #3 from koron/proxy-set

Proxy set

README.md

@@ -1,7 +1,7 @@
 # dProxy - document proxy
 
 dProxy is a proxy to access `interface{}` (document) by simple query.
-It is intetedd to be used with `json.Unmarshal()` or `json.NewDecorder()`.
+It is intented to be used with `json.Unmarshal()` or `json.NewDecorder()`.
 
 See codes for overview.
 
@@ -79,7 +79,17 @@ _, err = dproxy.New(v).M("data").M("kustom").String()
     fmt.Println(err)
     ```
 
-    You can verify queries easily.
+7.  If you tried to get a value as different type, get an error.
+
+    ```go
+    // OOPS! "cities[3]" (=200) should be float64 or int64.
+    _, err := p.M("cities").A(3).String()
+
+    // "not matched types: expected=string actual=float64: cities[3]"
+    fmt.Println(err)
+    ```
+
+8.  You can verify queries easily.
 
 
 ## LICENSE

error.go

@@ -1,6 +1,9 @@
 package dproxy
 
-import "fmt"
+import (
+	"fmt"
+	"strconv"
+)
 
 // ErrorType is type of errors
 type ErrorType int
@@ -24,12 +27,19 @@ type Error interface {
 
 type errorProxy struct {
 	errorType ErrorType
-	parent    Proxy
-	address   string
+	parent    frame
+	label     string
 	expected  Type
 	actual    Type
 }
 
+// errorProxy implements error, Proxy and ProxySet.
+var (
+	_ error    = (*errorProxy)(nil)
+	_ Proxy    = (*errorProxy)(nil)
+	_ ProxySet = (*errorProxy)(nil)
+)
+
 func (p *errorProxy) Nil() bool {
 	return false
 }
@@ -66,12 +76,56 @@ func (p *errorProxy) M(k string) Proxy {
 	return p
 }
 
-func (p *errorProxy) getParent() Proxy {
+func (p *errorProxy) Empty() bool {
+	return true
+}
+
+func (p *errorProxy) Len() int {
+	return 0
+}
+
+func (p *errorProxy) BoolArray() ([]bool, error) {
+	return nil, p
+}
+
+func (p *errorProxy) Int64Array() ([]int64, error) {
+	return nil, p
+}
+
+func (p *errorProxy) Float64Array() ([]float64, error) {
+	return nil, p
+}
+
+func (p *errorProxy) StringArray() ([]string, error) {
+	return nil, p
+}
+
+func (p *errorProxy) ArrayArray() ([][]interface{}, error) {
+	return nil, p
+}
+
+func (p *errorProxy) MapArray() ([]map[string]interface{}, error) {
+	return nil, p
+}
+
+func (p *errorProxy) ProxySet() ProxySet {
+	return p
+}
+
+func (p *errorProxy) Q(k string) ProxySet {
+	return p
+}
+
+func (p *errorProxy) Qc(k string) ProxySet {
+	return p
+}
+
+func (p *errorProxy) parentFrame() frame {
 	return p.parent
 }
 
-func (p *errorProxy) getAddress() string {
-	return p.address
+func (p *errorProxy) frameLabel() string {
+	return p.label
 }
 
 func (p *errorProxy) Error() string {
@@ -91,22 +145,10 @@ func (p *errorProxy) ErrorType() ErrorType {
 }
 
 func (p *errorProxy) FullAddress() string {
-	x := 0
-	for q := Proxy(p); q != nil; q = q.getParent() {
-		x += len(q.getAddress())
-	}
-	b := make([]byte, x)
-	for q := Proxy(p); q != nil; q = q.getParent() {
-		x -= len(q.getAddress())
-		copy(b[x:], q.getAddress())
-	}
-	if b[0] == '.' {
-		return string(b[1:])
-	}
-	return string(b)
+	return fullAddress(p)
 }
 
-func mismatchError(p Proxy, expected Type, actual interface{}) *errorProxy {
+func typeError(p frame, expected Type, actual interface{}) *errorProxy {
 	return &errorProxy{
 		errorType: Etype,
 		parent:    p,
@@ -115,10 +157,18 @@ func mismatchError(p Proxy, expected Type, actual interface{}) *errorProxy {
 	}
 }
 
-func addressError(p Proxy, address string) *errorProxy {
+func elementTypeError(p frame, index int, expected Type, actual interface{}) *errorProxy {
+	q := &simpleFrame{
+		parent: p,
+		label:  "[" + strconv.Itoa(index) + "]",
+	}
+	return typeError(q, expected, actual)
+}
+
+func notfoundError(p frame, address string) *errorProxy {
 	return &errorProxy{
 		errorType: Enotfound,
 		parent:    p,
-		address:   address,
+		label:     address,
 	}
 }

frame.go

@@ -0,0 +1,39 @@
+package dproxy
+
+type frame interface {
+	// parentFrame returns parent frame.
+	parentFrame() frame
+	// frameLabel return label of frame.
+	frameLabel() string
+}
+
+func fullAddress(f frame) string {
+	x := 0
+	for g := f; g != nil; g = g.parentFrame() {
+		x += len(g.frameLabel())
+	}
+	b := make([]byte, x)
+	for g := f; g != nil; g = g.parentFrame() {
+		x -= len(g.frameLabel())
+		copy(b[x:], g.frameLabel())
+	}
+	if b[0] == '.' {
+		return string(b[1:])
+	}
+	return string(b)
+}
+
+type simpleFrame struct {
+	parent frame
+	label  string
+}
+
+var _ frame = (*simpleFrame)(nil)
+
+func (f *simpleFrame) parentFrame() frame {
+	return f.parent
+}
+
+func (f *simpleFrame) frameLabel() string {
+	return f.label
+}

proxy.go

@@ -29,11 +29,61 @@ type Proxy interface {
 	// M returns an item from value treated as the map.
 	M(k string) Proxy
 
-	getParent() Proxy
-	getAddress() string
+	// ProxySet returns a set which converted from its array value.
+	ProxySet() ProxySet
+
+	// Q returns set of all items which property matchs with k.
+	Q(k string) ProxySet
+
+	// Proxy implements frame.
+	frame
+}
+
+// ProxySet proxies to access to set.
+type ProxySet interface {
+	// Empty returns true when the set is empty.
+	Empty() bool
+
+	// Len returns count of items in the set.
+	Len() int
+
+	// BoolArray returns []bool which converterd from the set.
+	BoolArray() ([]bool, error)
+
+	// Int64Array returns []int64 which converterd from the set.
+	Int64Array() ([]int64, error)
+
+	// Float64Array returns []float64 which converterd from the set.
+	Float64Array() ([]float64, error)
+
+	// StringArray returns []string which converterd from the set.
+	StringArray() ([]string, error)
+
+	// ArrayArray returns [][]interface{} which converterd from the set.
+	ArrayArray() ([][]interface{}, error)
+
+	// MapArray returns []map[string]interface{} which converterd from the set.
+	MapArray() ([]map[string]interface{}, error)
+
+	// A returns an proxy for index in the set.
+	A(n int) Proxy
+
+	// Q returns set of all items which property matchs with k.
+	Q(k string) ProxySet
+
+	// Qc returns set of property of all items.
+	Qc(k string) ProxySet
+
+	// Proxy implements frame.
+	frame
 }
 
-// New creates a new proxy object.
+// New creates a new Proxy instance for v.
 func New(v interface{}) Proxy {
 	return &valueProxy{value: v}
 }
+
+// NewSet create a new ProxySet instance for v.
+func NewSet(v []interface{}) ProxySet {
+	return &setProxy{values: v}
+}

proxy_test.go

@@ -13,6 +13,30 @@ func parseJSON(s string) interface{} {
 	return v
 }
 
+func equalStrings(a, b []string) bool {
+	if len(a) != len(b) {
+		return false
+	}
+	for i, s := range a {
+		if s != b[i] {
+			return false
+		}
+	}
+	return true
+}
+
+func equalInts(a, b []int64) bool {
+	if len(a) != len(b) {
+		return false
+	}
+	for i, s := range a {
+		if s != b[i] {
+			return false
+		}
+	}
+	return true
+}
+
 func TestReadme(t *testing.T) {
 	v := parseJSON(`{
 		"cities": [ "tokyo", 100, "osaka", 200, "hakata", 300 ],