act/pkg/exprparser/interpreter.go
2023-09-24 15:09:26 -04:00

636 lines
16 KiB
Go

package exprparser
import (
"encoding"
"fmt"
"math"
"reflect"
"strings"
"github.com/nektos/act/pkg/model"
"github.com/rhysd/actionlint"
)
type EvaluationEnvironment struct {
Github *model.GithubContext
Env map[string]string
Job *model.JobContext
Jobs *map[string]*model.WorkflowCallResult
Steps map[string]*model.StepResult
Runner map[string]interface{}
Secrets map[string]string
Vars map[string]string
Strategy map[string]interface{}
Matrix map[string]interface{}
Needs map[string]Needs
Inputs map[string]interface{}
}
type Needs struct {
Outputs map[string]string `json:"outputs"`
Result string `json:"result"`
}
type Config struct {
Run *model.Run
WorkingDir string
Context string
}
type DefaultStatusCheck int
const (
DefaultStatusCheckNone DefaultStatusCheck = iota
DefaultStatusCheckSuccess
DefaultStatusCheckAlways
DefaultStatusCheckCanceled
DefaultStatusCheckFailure
)
func (dsc DefaultStatusCheck) String() string {
switch dsc {
case DefaultStatusCheckSuccess:
return "success"
case DefaultStatusCheckAlways:
return "always"
case DefaultStatusCheckCanceled:
return "cancelled"
case DefaultStatusCheckFailure:
return "failure"
}
return ""
}
type Interpreter interface {
Evaluate(input string, defaultStatusCheck DefaultStatusCheck) (interface{}, error)
}
type interperterImpl struct {
env *EvaluationEnvironment
config Config
}
func NewInterpeter(env *EvaluationEnvironment, config Config) Interpreter {
return &interperterImpl{
env: env,
config: config,
}
}
func (impl *interperterImpl) Evaluate(input string, defaultStatusCheck DefaultStatusCheck) (interface{}, error) {
input = strings.TrimPrefix(input, "${{")
if defaultStatusCheck != DefaultStatusCheckNone && input == "" {
input = "success()"
}
parser := actionlint.NewExprParser()
exprNode, err := parser.Parse(actionlint.NewExprLexer(input + "}}"))
if err != nil {
return nil, fmt.Errorf("Failed to parse: %s", err.Message)
}
if defaultStatusCheck != DefaultStatusCheckNone {
hasStatusCheckFunction := false
actionlint.VisitExprNode(exprNode, func(node, _ actionlint.ExprNode, entering bool) {
if funcCallNode, ok := node.(*actionlint.FuncCallNode); entering && ok {
switch strings.ToLower(funcCallNode.Callee) {
case "success", "always", "cancelled", "failure":
hasStatusCheckFunction = true
}
}
})
if !hasStatusCheckFunction {
exprNode = &actionlint.LogicalOpNode{
Kind: actionlint.LogicalOpNodeKindAnd,
Left: &actionlint.FuncCallNode{
Callee: defaultStatusCheck.String(),
Args: []actionlint.ExprNode{},
},
Right: exprNode,
}
}
}
result, err2 := impl.evaluateNode(exprNode)
return result, err2
}
func (impl *interperterImpl) evaluateNode(exprNode actionlint.ExprNode) (interface{}, error) {
switch node := exprNode.(type) {
case *actionlint.VariableNode:
return impl.evaluateVariable(node)
case *actionlint.BoolNode:
return node.Value, nil
case *actionlint.NullNode:
return nil, nil
case *actionlint.IntNode:
return node.Value, nil
case *actionlint.FloatNode:
return node.Value, nil
case *actionlint.StringNode:
return node.Value, nil
case *actionlint.IndexAccessNode:
return impl.evaluateIndexAccess(node)
case *actionlint.ObjectDerefNode:
return impl.evaluateObjectDeref(node)
case *actionlint.ArrayDerefNode:
return impl.evaluateArrayDeref(node)
case *actionlint.NotOpNode:
return impl.evaluateNot(node)
case *actionlint.CompareOpNode:
return impl.evaluateCompare(node)
case *actionlint.LogicalOpNode:
return impl.evaluateLogicalCompare(node)
case *actionlint.FuncCallNode:
return impl.evaluateFuncCall(node)
default:
return nil, fmt.Errorf("Fatal error! Unknown node type: %s node: %+v", reflect.TypeOf(exprNode), exprNode)
}
}
//nolint:gocyclo
func (impl *interperterImpl) evaluateVariable(variableNode *actionlint.VariableNode) (interface{}, error) {
switch strings.ToLower(variableNode.Name) {
case "github":
return impl.env.Github, nil
case "gitea": // compatible with Gitea
return impl.env.Github, nil
case "env":
return impl.env.Env, nil
case "job":
return impl.env.Job, nil
case "jobs":
if impl.env.Jobs == nil {
return nil, fmt.Errorf("Unavailable context: jobs")
}
return impl.env.Jobs, nil
case "steps":
return impl.env.Steps, nil
case "runner":
return impl.env.Runner, nil
case "secrets":
return impl.env.Secrets, nil
case "vars":
return impl.env.Vars, nil
case "strategy":
return impl.env.Strategy, nil
case "matrix":
return impl.env.Matrix, nil
case "needs":
return impl.env.Needs, nil
case "inputs":
return impl.env.Inputs, nil
case "infinity":
return math.Inf(1), nil
case "nan":
return math.NaN(), nil
default:
return nil, fmt.Errorf("Unavailable context: %s", variableNode.Name)
}
}
func (impl *interperterImpl) evaluateIndexAccess(indexAccessNode *actionlint.IndexAccessNode) (interface{}, error) {
left, err := impl.evaluateNode(indexAccessNode.Operand)
if err != nil {
return nil, err
}
leftValue := reflect.ValueOf(left)
right, err := impl.evaluateNode(indexAccessNode.Index)
if err != nil {
return nil, err
}
rightValue := reflect.ValueOf(right)
switch rightValue.Kind() {
case reflect.String:
return impl.getPropertyValue(leftValue, rightValue.String())
case reflect.Int:
switch leftValue.Kind() {
case reflect.Slice:
if rightValue.Int() < 0 || rightValue.Int() >= int64(leftValue.Len()) {
return nil, nil
}
return leftValue.Index(int(rightValue.Int())).Interface(), nil
default:
return nil, nil
}
default:
return nil, nil
}
}
func (impl *interperterImpl) evaluateObjectDeref(objectDerefNode *actionlint.ObjectDerefNode) (interface{}, error) {
left, err := impl.evaluateNode(objectDerefNode.Receiver)
if err != nil {
return nil, err
}
return impl.getPropertyValue(reflect.ValueOf(left), objectDerefNode.Property)
}
func (impl *interperterImpl) evaluateArrayDeref(arrayDerefNode *actionlint.ArrayDerefNode) (interface{}, error) {
left, err := impl.evaluateNode(arrayDerefNode.Receiver)
if err != nil {
return nil, err
}
return impl.getSafeValue(reflect.ValueOf(left)), nil
}
func (impl *interperterImpl) getPropertyValue(left reflect.Value, property string) (value interface{}, err error) {
switch left.Kind() {
case reflect.Ptr:
return impl.getPropertyValue(left.Elem(), property)
case reflect.Struct:
leftType := left.Type()
for i := 0; i < leftType.NumField(); i++ {
jsonName := leftType.Field(i).Tag.Get("json")
if jsonName == property {
property = leftType.Field(i).Name
break
}
}
fieldValue := left.FieldByNameFunc(func(name string) bool {
return strings.EqualFold(name, property)
})
if fieldValue.Kind() == reflect.Invalid {
return "", nil
}
i := fieldValue.Interface()
// The type stepStatus int is an integer, but should be treated as string
if m, ok := i.(encoding.TextMarshaler); ok {
text, err := m.MarshalText()
if err != nil {
return nil, err
}
return string(text), nil
}
return i, nil
case reflect.Map:
iter := left.MapRange()
for iter.Next() {
key := iter.Key()
switch key.Kind() {
case reflect.String:
if strings.EqualFold(key.String(), property) {
return impl.getMapValue(iter.Value())
}
default:
return nil, fmt.Errorf("'%s' in map key not implemented", key.Kind())
}
}
return nil, nil
case reflect.Slice:
var values []interface{}
for i := 0; i < left.Len(); i++ {
value, err := impl.getPropertyValue(left.Index(i).Elem(), property)
if err != nil {
return nil, err
}
values = append(values, value)
}
return values, nil
}
return nil, nil
}
func (impl *interperterImpl) getMapValue(value reflect.Value) (interface{}, error) {
if value.Kind() == reflect.Ptr {
return impl.getMapValue(value.Elem())
}
return value.Interface(), nil
}
func (impl *interperterImpl) evaluateNot(notNode *actionlint.NotOpNode) (interface{}, error) {
operand, err := impl.evaluateNode(notNode.Operand)
if err != nil {
return nil, err
}
return !IsTruthy(operand), nil
}
func (impl *interperterImpl) evaluateCompare(compareNode *actionlint.CompareOpNode) (interface{}, error) {
left, err := impl.evaluateNode(compareNode.Left)
if err != nil {
return nil, err
}
right, err := impl.evaluateNode(compareNode.Right)
if err != nil {
return nil, err
}
leftValue := reflect.ValueOf(left)
rightValue := reflect.ValueOf(right)
return impl.compareValues(leftValue, rightValue, compareNode.Kind)
}
func (impl *interperterImpl) compareValues(leftValue reflect.Value, rightValue reflect.Value, kind actionlint.CompareOpNodeKind) (interface{}, error) {
if leftValue.Kind() != rightValue.Kind() {
if !impl.isNumber(leftValue) {
leftValue = impl.coerceToNumber(leftValue)
}
if !impl.isNumber(rightValue) {
rightValue = impl.coerceToNumber(rightValue)
}
}
switch leftValue.Kind() {
case reflect.Bool:
return impl.compareNumber(float64(impl.coerceToNumber(leftValue).Int()), float64(impl.coerceToNumber(rightValue).Int()), kind)
case reflect.String:
return impl.compareString(strings.ToLower(leftValue.String()), strings.ToLower(rightValue.String()), kind)
case reflect.Int:
if rightValue.Kind() == reflect.Float64 {
return impl.compareNumber(float64(leftValue.Int()), rightValue.Float(), kind)
}
return impl.compareNumber(float64(leftValue.Int()), float64(rightValue.Int()), kind)
case reflect.Float64:
if rightValue.Kind() == reflect.Int {
return impl.compareNumber(leftValue.Float(), float64(rightValue.Int()), kind)
}
return impl.compareNumber(leftValue.Float(), rightValue.Float(), kind)
case reflect.Invalid:
if rightValue.Kind() == reflect.Invalid {
return true, nil
}
// not possible situation - params are converted to the same type in code above
return nil, fmt.Errorf("Compare params of Invalid type: left: %+v, right: %+v", leftValue.Kind(), rightValue.Kind())
default:
return nil, fmt.Errorf("Compare not implemented for types: left: %+v, right: %+v", leftValue.Kind(), rightValue.Kind())
}
}
func (impl *interperterImpl) coerceToNumber(value reflect.Value) reflect.Value {
switch value.Kind() {
case reflect.Invalid:
return reflect.ValueOf(0)
case reflect.Bool:
switch value.Bool() {
case true:
return reflect.ValueOf(1)
case false:
return reflect.ValueOf(0)
}
case reflect.String:
if value.String() == "" {
return reflect.ValueOf(0)
}
// try to parse the string as a number
evaluated, err := impl.Evaluate(value.String(), DefaultStatusCheckNone)
if err != nil {
return reflect.ValueOf(math.NaN())
}
if value := reflect.ValueOf(evaluated); impl.isNumber(value) {
return value
}
}
return reflect.ValueOf(math.NaN())
}
func (impl *interperterImpl) coerceToString(value reflect.Value) reflect.Value {
switch value.Kind() {
case reflect.Invalid:
return reflect.ValueOf("")
case reflect.Bool:
switch value.Bool() {
case true:
return reflect.ValueOf("true")
case false:
return reflect.ValueOf("false")
}
case reflect.String:
return value
case reflect.Int:
return reflect.ValueOf(fmt.Sprint(value))
case reflect.Float64:
if math.IsInf(value.Float(), 1) {
return reflect.ValueOf("Infinity")
} else if math.IsInf(value.Float(), -1) {
return reflect.ValueOf("-Infinity")
}
return reflect.ValueOf(fmt.Sprint(value))
case reflect.Slice:
return reflect.ValueOf("Array")
case reflect.Map:
return reflect.ValueOf("Object")
}
return value
}
func (impl *interperterImpl) compareString(left string, right string, kind actionlint.CompareOpNodeKind) (bool, error) {
switch kind {
case actionlint.CompareOpNodeKindLess:
return left < right, nil
case actionlint.CompareOpNodeKindLessEq:
return left <= right, nil
case actionlint.CompareOpNodeKindGreater:
return left > right, nil
case actionlint.CompareOpNodeKindGreaterEq:
return left >= right, nil
case actionlint.CompareOpNodeKindEq:
return left == right, nil
case actionlint.CompareOpNodeKindNotEq:
return left != right, nil
default:
return false, fmt.Errorf("TODO: not implemented to compare '%+v'", kind)
}
}
func (impl *interperterImpl) compareNumber(left float64, right float64, kind actionlint.CompareOpNodeKind) (bool, error) {
switch kind {
case actionlint.CompareOpNodeKindLess:
return left < right, nil
case actionlint.CompareOpNodeKindLessEq:
return left <= right, nil
case actionlint.CompareOpNodeKindGreater:
return left > right, nil
case actionlint.CompareOpNodeKindGreaterEq:
return left >= right, nil
case actionlint.CompareOpNodeKindEq:
return left == right, nil
case actionlint.CompareOpNodeKindNotEq:
return left != right, nil
default:
return false, fmt.Errorf("TODO: not implemented to compare '%+v'", kind)
}
}
func IsTruthy(input interface{}) bool {
value := reflect.ValueOf(input)
switch value.Kind() {
case reflect.Bool:
return value.Bool()
case reflect.String:
return value.String() != ""
case reflect.Int:
return value.Int() != 0
case reflect.Float64:
if math.IsNaN(value.Float()) {
return false
}
return value.Float() != 0
case reflect.Map, reflect.Slice:
return true
default:
return false
}
}
func (impl *interperterImpl) isNumber(value reflect.Value) bool {
switch value.Kind() {
case reflect.Int, reflect.Float64:
return true
default:
return false
}
}
func (impl *interperterImpl) getSafeValue(value reflect.Value) interface{} {
switch value.Kind() {
case reflect.Invalid:
return nil
case reflect.Float64:
if value.Float() == 0 {
return 0
}
}
return value.Interface()
}
func (impl *interperterImpl) evaluateLogicalCompare(compareNode *actionlint.LogicalOpNode) (interface{}, error) {
left, err := impl.evaluateNode(compareNode.Left)
if err != nil {
return nil, err
}
leftValue := reflect.ValueOf(left)
if IsTruthy(left) == (compareNode.Kind == actionlint.LogicalOpNodeKindOr) {
return impl.getSafeValue(leftValue), nil
}
right, err := impl.evaluateNode(compareNode.Right)
if err != nil {
return nil, err
}
rightValue := reflect.ValueOf(right)
switch compareNode.Kind {
case actionlint.LogicalOpNodeKindAnd:
return impl.getSafeValue(rightValue), nil
case actionlint.LogicalOpNodeKindOr:
return impl.getSafeValue(rightValue), nil
}
return nil, fmt.Errorf("Unable to compare incompatibles types '%s' and '%s'", leftValue.Kind(), rightValue.Kind())
}
//nolint:gocyclo
func (impl *interperterImpl) evaluateFuncCall(funcCallNode *actionlint.FuncCallNode) (interface{}, error) {
args := make([]reflect.Value, 0)
for _, arg := range funcCallNode.Args {
value, err := impl.evaluateNode(arg)
if err != nil {
return nil, err
}
args = append(args, reflect.ValueOf(value))
}
switch strings.ToLower(funcCallNode.Callee) {
case "contains":
return impl.contains(args[0], args[1])
case "startswith":
return impl.startsWith(args[0], args[1])
case "endswith":
return impl.endsWith(args[0], args[1])
case "format":
return impl.format(args[0], args[1:]...)
case "join":
if len(args) == 1 {
return impl.join(args[0], reflect.ValueOf(","))
}
return impl.join(args[0], args[1])
case "tojson":
return impl.toJSON(args[0])
case "fromjson":
return impl.fromJSON(args[0])
case "hashfiles":
return impl.hashFiles(args...)
case "always":
return impl.always()
case "success":
if impl.config.Context == "job" {
return impl.jobSuccess()
}
if impl.config.Context == "step" {
return impl.stepSuccess()
}
return nil, fmt.Errorf("Context '%s' must be one of 'job' or 'step'", impl.config.Context)
case "failure":
if impl.config.Context == "job" {
return impl.jobFailure()
}
if impl.config.Context == "step" {
return impl.stepFailure()
}
return nil, fmt.Errorf("Context '%s' must be one of 'job' or 'step'", impl.config.Context)
case "cancelled":
return impl.cancelled()
default:
return nil, fmt.Errorf("TODO: '%s' not implemented", funcCallNode.Callee)
}
}