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authorNiall Sheridan <nsheridan@gmail.com>2016-06-06 14:44:38 +0100
committerNiall Sheridan <nsheridan@gmail.com>2016-06-06 14:44:38 +0100
commit067ad51b6a6ee8829612f51a6e6b2ade3eaa61b3 (patch)
tree301d2a7303e2b5db0c3fa1911d799e16f921d9dc /vendor/github.com/jmespath/go-jmespath/interpreter.go
parent5ca59399fe0880368f88d17c0c9d781d836969c6 (diff)
parenta18a13fb09eac00cdacf1f74080524182b7243de (diff)
Merge pull request #17 from nsheridan/vendor
update dependencies
Diffstat (limited to 'vendor/github.com/jmespath/go-jmespath/interpreter.go')
-rw-r--r--vendor/github.com/jmespath/go-jmespath/interpreter.go418
1 files changed, 418 insertions, 0 deletions
diff --git a/vendor/github.com/jmespath/go-jmespath/interpreter.go b/vendor/github.com/jmespath/go-jmespath/interpreter.go
new file mode 100644
index 0000000..13c7460
--- /dev/null
+++ b/vendor/github.com/jmespath/go-jmespath/interpreter.go
@@ -0,0 +1,418 @@
+package jmespath
+
+import (
+ "errors"
+ "reflect"
+ "unicode"
+ "unicode/utf8"
+)
+
+/* This is a tree based interpreter. It walks the AST and directly
+ interprets the AST to search through a JSON document.
+*/
+
+type treeInterpreter struct {
+ fCall *functionCaller
+}
+
+func newInterpreter() *treeInterpreter {
+ interpreter := treeInterpreter{}
+ interpreter.fCall = newFunctionCaller()
+ return &interpreter
+}
+
+type expRef struct {
+ ref ASTNode
+}
+
+// Execute takes an ASTNode and input data and interprets the AST directly.
+// It will produce the result of applying the JMESPath expression associated
+// with the ASTNode to the input data "value".
+func (intr *treeInterpreter) Execute(node ASTNode, value interface{}) (interface{}, error) {
+ switch node.nodeType {
+ case ASTComparator:
+ left, err := intr.Execute(node.children[0], value)
+ if err != nil {
+ return nil, err
+ }
+ right, err := intr.Execute(node.children[1], value)
+ if err != nil {
+ return nil, err
+ }
+ switch node.value {
+ case tEQ:
+ return objsEqual(left, right), nil
+ case tNE:
+ return !objsEqual(left, right), nil
+ }
+ leftNum, ok := left.(float64)
+ if !ok {
+ return nil, nil
+ }
+ rightNum, ok := right.(float64)
+ if !ok {
+ return nil, nil
+ }
+ switch node.value {
+ case tGT:
+ return leftNum > rightNum, nil
+ case tGTE:
+ return leftNum >= rightNum, nil
+ case tLT:
+ return leftNum < rightNum, nil
+ case tLTE:
+ return leftNum <= rightNum, nil
+ }
+ case ASTExpRef:
+ return expRef{ref: node.children[0]}, nil
+ case ASTFunctionExpression:
+ resolvedArgs := []interface{}{}
+ for _, arg := range node.children {
+ current, err := intr.Execute(arg, value)
+ if err != nil {
+ return nil, err
+ }
+ resolvedArgs = append(resolvedArgs, current)
+ }
+ return intr.fCall.CallFunction(node.value.(string), resolvedArgs, intr)
+ case ASTField:
+ if m, ok := value.(map[string]interface{}); ok {
+ key := node.value.(string)
+ return m[key], nil
+ }
+ return intr.fieldFromStruct(node.value.(string), value)
+ case ASTFilterProjection:
+ left, err := intr.Execute(node.children[0], value)
+ if err != nil {
+ return nil, nil
+ }
+ sliceType, ok := left.([]interface{})
+ if !ok {
+ if isSliceType(left) {
+ return intr.filterProjectionWithReflection(node, left)
+ }
+ return nil, nil
+ }
+ compareNode := node.children[2]
+ collected := []interface{}{}
+ for _, element := range sliceType {
+ result, err := intr.Execute(compareNode, element)
+ if err != nil {
+ return nil, err
+ }
+ if !isFalse(result) {
+ current, err := intr.Execute(node.children[1], element)
+ if err != nil {
+ return nil, err
+ }
+ if current != nil {
+ collected = append(collected, current)
+ }
+ }
+ }
+ return collected, nil
+ case ASTFlatten:
+ left, err := intr.Execute(node.children[0], value)
+ if err != nil {
+ return nil, nil
+ }
+ sliceType, ok := left.([]interface{})
+ if !ok {
+ // If we can't type convert to []interface{}, there's
+ // a chance this could still work via reflection if we're
+ // dealing with user provided types.
+ if isSliceType(left) {
+ return intr.flattenWithReflection(left)
+ }
+ return nil, nil
+ }
+ flattened := []interface{}{}
+ for _, element := range sliceType {
+ if elementSlice, ok := element.([]interface{}); ok {
+ flattened = append(flattened, elementSlice...)
+ } else if isSliceType(element) {
+ reflectFlat := []interface{}{}
+ v := reflect.ValueOf(element)
+ for i := 0; i < v.Len(); i++ {
+ reflectFlat = append(reflectFlat, v.Index(i).Interface())
+ }
+ flattened = append(flattened, reflectFlat...)
+ } else {
+ flattened = append(flattened, element)
+ }
+ }
+ return flattened, nil
+ case ASTIdentity, ASTCurrentNode:
+ return value, nil
+ case ASTIndex:
+ if sliceType, ok := value.([]interface{}); ok {
+ index := node.value.(int)
+ if index < 0 {
+ index += len(sliceType)
+ }
+ if index < len(sliceType) && index >= 0 {
+ return sliceType[index], nil
+ }
+ return nil, nil
+ }
+ // Otherwise try via reflection.
+ rv := reflect.ValueOf(value)
+ if rv.Kind() == reflect.Slice {
+ index := node.value.(int)
+ if index < 0 {
+ index += rv.Len()
+ }
+ if index < rv.Len() && index >= 0 {
+ v := rv.Index(index)
+ return v.Interface(), nil
+ }
+ }
+ return nil, nil
+ case ASTKeyValPair:
+ return intr.Execute(node.children[0], value)
+ case ASTLiteral:
+ return node.value, nil
+ case ASTMultiSelectHash:
+ if value == nil {
+ return nil, nil
+ }
+ collected := make(map[string]interface{})
+ for _, child := range node.children {
+ current, err := intr.Execute(child, value)
+ if err != nil {
+ return nil, err
+ }
+ key := child.value.(string)
+ collected[key] = current
+ }
+ return collected, nil
+ case ASTMultiSelectList:
+ if value == nil {
+ return nil, nil
+ }
+ collected := []interface{}{}
+ for _, child := range node.children {
+ current, err := intr.Execute(child, value)
+ if err != nil {
+ return nil, err
+ }
+ collected = append(collected, current)
+ }
+ return collected, nil
+ case ASTOrExpression:
+ matched, err := intr.Execute(node.children[0], value)
+ if err != nil {
+ return nil, err
+ }
+ if isFalse(matched) {
+ matched, err = intr.Execute(node.children[1], value)
+ if err != nil {
+ return nil, err
+ }
+ }
+ return matched, nil
+ case ASTAndExpression:
+ matched, err := intr.Execute(node.children[0], value)
+ if err != nil {
+ return nil, err
+ }
+ if isFalse(matched) {
+ return matched, nil
+ }
+ return intr.Execute(node.children[1], value)
+ case ASTNotExpression:
+ matched, err := intr.Execute(node.children[0], value)
+ if err != nil {
+ return nil, err
+ }
+ if isFalse(matched) {
+ return true, nil
+ }
+ return false, nil
+ case ASTPipe:
+ result := value
+ var err error
+ for _, child := range node.children {
+ result, err = intr.Execute(child, result)
+ if err != nil {
+ return nil, err
+ }
+ }
+ return result, nil
+ case ASTProjection:
+ left, err := intr.Execute(node.children[0], value)
+ if err != nil {
+ return nil, err
+ }
+ sliceType, ok := left.([]interface{})
+ if !ok {
+ if isSliceType(left) {
+ return intr.projectWithReflection(node, left)
+ }
+ return nil, nil
+ }
+ collected := []interface{}{}
+ var current interface{}
+ for _, element := range sliceType {
+ current, err = intr.Execute(node.children[1], element)
+ if err != nil {
+ return nil, err
+ }
+ if current != nil {
+ collected = append(collected, current)
+ }
+ }
+ return collected, nil
+ case ASTSubexpression, ASTIndexExpression:
+ left, err := intr.Execute(node.children[0], value)
+ if err != nil {
+ return nil, err
+ }
+ return intr.Execute(node.children[1], left)
+ case ASTSlice:
+ sliceType, ok := value.([]interface{})
+ if !ok {
+ if isSliceType(value) {
+ return intr.sliceWithReflection(node, value)
+ }
+ return nil, nil
+ }
+ parts := node.value.([]*int)
+ sliceParams := make([]sliceParam, 3)
+ for i, part := range parts {
+ if part != nil {
+ sliceParams[i].Specified = true
+ sliceParams[i].N = *part
+ }
+ }
+ return slice(sliceType, sliceParams)
+ case ASTValueProjection:
+ left, err := intr.Execute(node.children[0], value)
+ if err != nil {
+ return nil, nil
+ }
+ mapType, ok := left.(map[string]interface{})
+ if !ok {
+ return nil, nil
+ }
+ values := make([]interface{}, len(mapType))
+ for _, value := range mapType {
+ values = append(values, value)
+ }
+ collected := []interface{}{}
+ for _, element := range values {
+ current, err := intr.Execute(node.children[1], element)
+ if err != nil {
+ return nil, err
+ }
+ if current != nil {
+ collected = append(collected, current)
+ }
+ }
+ return collected, nil
+ }
+ return nil, errors.New("Unknown AST node: " + node.nodeType.String())
+}
+
+func (intr *treeInterpreter) fieldFromStruct(key string, value interface{}) (interface{}, error) {
+ rv := reflect.ValueOf(value)
+ first, n := utf8.DecodeRuneInString(key)
+ fieldName := string(unicode.ToUpper(first)) + key[n:]
+ if rv.Kind() == reflect.Struct {
+ v := rv.FieldByName(fieldName)
+ if !v.IsValid() {
+ return nil, nil
+ }
+ return v.Interface(), nil
+ } else if rv.Kind() == reflect.Ptr {
+ // Handle multiple levels of indirection?
+ if rv.IsNil() {
+ return nil, nil
+ }
+ rv = rv.Elem()
+ v := rv.FieldByName(fieldName)
+ if !v.IsValid() {
+ return nil, nil
+ }
+ return v.Interface(), nil
+ }
+ return nil, nil
+}
+
+func (intr *treeInterpreter) flattenWithReflection(value interface{}) (interface{}, error) {
+ v := reflect.ValueOf(value)
+ flattened := []interface{}{}
+ for i := 0; i < v.Len(); i++ {
+ element := v.Index(i).Interface()
+ if reflect.TypeOf(element).Kind() == reflect.Slice {
+ // Then insert the contents of the element
+ // slice into the flattened slice,
+ // i.e flattened = append(flattened, mySlice...)
+ elementV := reflect.ValueOf(element)
+ for j := 0; j < elementV.Len(); j++ {
+ flattened = append(
+ flattened, elementV.Index(j).Interface())
+ }
+ } else {
+ flattened = append(flattened, element)
+ }
+ }
+ return flattened, nil
+}
+
+func (intr *treeInterpreter) sliceWithReflection(node ASTNode, value interface{}) (interface{}, error) {
+ v := reflect.ValueOf(value)
+ parts := node.value.([]*int)
+ sliceParams := make([]sliceParam, 3)
+ for i, part := range parts {
+ if part != nil {
+ sliceParams[i].Specified = true
+ sliceParams[i].N = *part
+ }
+ }
+ final := []interface{}{}
+ for i := 0; i < v.Len(); i++ {
+ element := v.Index(i).Interface()
+ final = append(final, element)
+ }
+ return slice(final, sliceParams)
+}
+
+func (intr *treeInterpreter) filterProjectionWithReflection(node ASTNode, value interface{}) (interface{}, error) {
+ compareNode := node.children[2]
+ collected := []interface{}{}
+ v := reflect.ValueOf(value)
+ for i := 0; i < v.Len(); i++ {
+ element := v.Index(i).Interface()
+ result, err := intr.Execute(compareNode, element)
+ if err != nil {
+ return nil, err
+ }
+ if !isFalse(result) {
+ current, err := intr.Execute(node.children[1], element)
+ if err != nil {
+ return nil, err
+ }
+ if current != nil {
+ collected = append(collected, current)
+ }
+ }
+ }
+ return collected, nil
+}
+
+func (intr *treeInterpreter) projectWithReflection(node ASTNode, value interface{}) (interface{}, error) {
+ collected := []interface{}{}
+ v := reflect.ValueOf(value)
+ for i := 0; i < v.Len(); i++ {
+ element := v.Index(i).Interface()
+ result, err := intr.Execute(node.children[1], element)
+ if err != nil {
+ return nil, err
+ }
+ if result != nil {
+ collected = append(collected, result)
+ }
+ }
+ return collected, nil
+}