act/pkg/runner/expression.go

582 lines
15 KiB
Go

package runner
import (
"bytes"
"context"
"fmt"
"path"
"reflect"
"regexp"
"strings"
"time"
_ "embed"
"github.com/nektos/act/pkg/common"
"github.com/nektos/act/pkg/container"
"github.com/nektos/act/pkg/exprparser"
"github.com/nektos/act/pkg/model"
"gopkg.in/yaml.v3"
)
// ExpressionEvaluator is the interface for evaluating expressions
type ExpressionEvaluator interface {
evaluate(context.Context, string, exprparser.DefaultStatusCheck) (interface{}, error)
EvaluateYamlNode(context.Context, *yaml.Node) error
Interpolate(context.Context, string) string
}
// NewExpressionEvaluator creates a new evaluator
func (rc *RunContext) NewExpressionEvaluator(ctx context.Context) ExpressionEvaluator {
return rc.NewExpressionEvaluatorWithEnv(ctx, rc.GetEnv())
}
func (rc *RunContext) NewExpressionEvaluatorWithEnv(ctx context.Context, env map[string]string) ExpressionEvaluator {
var workflowCallResult map[string]*model.WorkflowCallResult
// todo: cleanup EvaluationEnvironment creation
using := make(map[string]exprparser.Needs)
strategy := make(map[string]interface{})
if rc.Run != nil {
job := rc.Run.Job()
if job != nil && job.Strategy != nil {
strategy["fail-fast"] = job.Strategy.FailFast
strategy["max-parallel"] = job.Strategy.MaxParallel
}
jobs := rc.Run.Workflow.Jobs
jobNeeds := rc.Run.Job().Needs()
for _, needs := range jobNeeds {
using[needs] = exprparser.Needs{
Outputs: jobs[needs].Outputs,
Result: jobs[needs].Result,
}
}
// only setup jobs context in case of workflow_call
// and existing expression evaluator (this means, jobs are at
// least ready to run)
if rc.caller != nil && rc.ExprEval != nil {
workflowCallResult = map[string]*model.WorkflowCallResult{}
for jobName, job := range jobs {
result := model.WorkflowCallResult{
Outputs: map[string]string{},
}
for k, v := range job.Outputs {
result.Outputs[k] = v
}
workflowCallResult[jobName] = &result
}
}
}
ghc := rc.getGithubContext(ctx)
inputs := getEvaluatorInputs(ctx, rc, nil, ghc)
ee := &exprparser.EvaluationEnvironment{
Github: ghc,
Env: env,
Job: rc.getJobContext(),
Jobs: &workflowCallResult,
// todo: should be unavailable
// but required to interpolate/evaluate the step outputs on the job
Steps: rc.getStepsContext(),
Secrets: getWorkflowSecrets(ctx, rc),
Vars: getWorkflowVars(ctx, rc),
Strategy: strategy,
Matrix: rc.Matrix,
Needs: using,
Inputs: inputs,
HashFiles: getHashFilesFunction(ctx, rc),
}
if rc.JobContainer != nil {
ee.Runner = rc.JobContainer.GetRunnerContext(ctx)
}
return expressionEvaluator{
interpreter: exprparser.NewInterpeter(ee, exprparser.Config{
Run: rc.Run,
WorkingDir: rc.Config.Workdir,
Context: "job",
}),
}
}
//go:embed hashfiles/index.js
var hashfiles string
// NewExpressionEvaluator creates a new evaluator
func (rc *RunContext) NewStepExpressionEvaluator(ctx context.Context, step step) ExpressionEvaluator {
// todo: cleanup EvaluationEnvironment creation
job := rc.Run.Job()
strategy := make(map[string]interface{})
if job.Strategy != nil {
strategy["fail-fast"] = job.Strategy.FailFast
strategy["max-parallel"] = job.Strategy.MaxParallel
}
jobs := rc.Run.Workflow.Jobs
jobNeeds := rc.Run.Job().Needs()
using := make(map[string]exprparser.Needs)
for _, needs := range jobNeeds {
using[needs] = exprparser.Needs{
Outputs: jobs[needs].Outputs,
Result: jobs[needs].Result,
}
}
ghc := rc.getGithubContext(ctx)
inputs := getEvaluatorInputs(ctx, rc, step, ghc)
ee := &exprparser.EvaluationEnvironment{
Github: step.getGithubContext(ctx),
Env: *step.getEnv(),
Job: rc.getJobContext(),
Steps: rc.getStepsContext(),
Secrets: getWorkflowSecrets(ctx, rc),
Vars: getWorkflowVars(ctx, rc),
Strategy: strategy,
Matrix: rc.Matrix,
Needs: using,
// todo: should be unavailable
// but required to interpolate/evaluate the inputs in actions/composite
Inputs: inputs,
HashFiles: getHashFilesFunction(ctx, rc),
}
if rc.JobContainer != nil {
ee.Runner = rc.JobContainer.GetRunnerContext(ctx)
}
return expressionEvaluator{
interpreter: exprparser.NewInterpeter(ee, exprparser.Config{
Run: rc.Run,
WorkingDir: rc.Config.Workdir,
Context: "step",
}),
}
}
func getHashFilesFunction(ctx context.Context, rc *RunContext) func(v []reflect.Value) (interface{}, error) {
hashFiles := func(v []reflect.Value) (interface{}, error) {
if rc.JobContainer != nil {
timeed, cancel := context.WithTimeout(ctx, time.Minute)
defer cancel()
name := "workflow/hashfiles/index.js"
hout := &bytes.Buffer{}
herr := &bytes.Buffer{}
patterns := []string{}
followSymlink := false
for i, p := range v {
s := p.String()
if i == 0 {
if strings.HasPrefix(s, "--") {
if strings.EqualFold(s, "--follow-symbolic-links") {
followSymlink = true
continue
}
return "", fmt.Errorf("Invalid glob option %s, available option: '--follow-symbolic-links'", s)
}
}
patterns = append(patterns, s)
}
env := map[string]string{}
for k, v := range rc.Env {
env[k] = v
}
env["patterns"] = strings.Join(patterns, "\n")
if followSymlink {
env["followSymbolicLinks"] = "true"
}
stdout, stderr := rc.JobContainer.ReplaceLogWriter(hout, herr)
_ = rc.JobContainer.Copy(rc.JobContainer.GetActPath(), &container.FileEntry{
Name: name,
Mode: 0o644,
Body: hashfiles,
}).
Then(rc.execJobContainer([]string{"node", path.Join(rc.JobContainer.GetActPath(), name)},
env, "", "")).
Finally(func(context.Context) error {
rc.JobContainer.ReplaceLogWriter(stdout, stderr)
return nil
})(timeed)
output := hout.String() + "\n" + herr.String()
guard := "__OUTPUT__"
outstart := strings.Index(output, guard)
if outstart != -1 {
outstart += len(guard)
outend := strings.Index(output[outstart:], guard)
if outend != -1 {
return output[outstart : outstart+outend], nil
}
}
}
return "", nil
}
return hashFiles
}
type expressionEvaluator struct {
interpreter exprparser.Interpreter
}
func (ee expressionEvaluator) evaluate(ctx context.Context, in string, defaultStatusCheck exprparser.DefaultStatusCheck) (interface{}, error) {
logger := common.Logger(ctx)
logger.Debugf("evaluating expression '%s'", in)
evaluated, err := ee.interpreter.Evaluate(in, defaultStatusCheck)
printable := regexp.MustCompile(`::add-mask::.*`).ReplaceAllString(fmt.Sprintf("%t", evaluated), "::add-mask::***)")
logger.Debugf("expression '%s' evaluated to '%s'", in, printable)
return evaluated, err
}
func (ee expressionEvaluator) evaluateScalarYamlNode(ctx context.Context, node *yaml.Node) (*yaml.Node, error) {
var in string
if err := node.Decode(&in); err != nil {
return nil, err
}
if !strings.Contains(in, "${{") || !strings.Contains(in, "}}") {
return nil, nil
}
expr, _ := rewriteSubExpression(ctx, in, false)
res, err := ee.evaluate(ctx, expr, exprparser.DefaultStatusCheckNone)
if err != nil {
return nil, err
}
ret := &yaml.Node{}
if err := ret.Encode(res); err != nil {
return nil, err
}
return ret, err
}
func (ee expressionEvaluator) evaluateMappingYamlNode(ctx context.Context, node *yaml.Node) (*yaml.Node, error) {
var ret *yaml.Node
// GitHub has this undocumented feature to merge maps, called insert directive
insertDirective := regexp.MustCompile(`\${{\s*insert\s*}}`)
for i := 0; i < len(node.Content)/2; i++ {
changed := func() error {
if ret == nil {
ret = &yaml.Node{}
if err := ret.Encode(node); err != nil {
return err
}
ret.Content = ret.Content[:i*2]
}
return nil
}
k := node.Content[i*2]
v := node.Content[i*2+1]
ev, err := ee.evaluateYamlNodeInternal(ctx, v)
if err != nil {
return nil, err
}
if ev != nil {
if err := changed(); err != nil {
return nil, err
}
} else {
ev = v
}
var sk string
// Merge the nested map of the insert directive
if k.Decode(&sk) == nil && insertDirective.MatchString(sk) {
if ev.Kind != yaml.MappingNode {
return nil, fmt.Errorf("failed to insert node %v into mapping %v unexpected type %v expected MappingNode", ev, node, ev.Kind)
}
if err := changed(); err != nil {
return nil, err
}
ret.Content = append(ret.Content, ev.Content...)
} else {
ek, err := ee.evaluateYamlNodeInternal(ctx, k)
if err != nil {
return nil, err
}
if ek != nil {
if err := changed(); err != nil {
return nil, err
}
} else {
ek = k
}
if ret != nil {
ret.Content = append(ret.Content, ek, ev)
}
}
}
return ret, nil
}
func (ee expressionEvaluator) evaluateSequenceYamlNode(ctx context.Context, node *yaml.Node) (*yaml.Node, error) {
var ret *yaml.Node
for i := 0; i < len(node.Content); i++ {
v := node.Content[i]
// Preserve nested sequences
wasseq := v.Kind == yaml.SequenceNode
ev, err := ee.evaluateYamlNodeInternal(ctx, v)
if err != nil {
return nil, err
}
if ev != nil {
if ret == nil {
ret = &yaml.Node{}
if err := ret.Encode(node); err != nil {
return nil, err
}
ret.Content = ret.Content[:i]
}
// GitHub has this undocumented feature to merge sequences / arrays
// We have a nested sequence via evaluation, merge the arrays
if ev.Kind == yaml.SequenceNode && !wasseq {
ret.Content = append(ret.Content, ev.Content...)
} else {
ret.Content = append(ret.Content, ev)
}
} else if ret != nil {
ret.Content = append(ret.Content, v)
}
}
return ret, nil
}
func (ee expressionEvaluator) evaluateYamlNodeInternal(ctx context.Context, node *yaml.Node) (*yaml.Node, error) {
switch node.Kind {
case yaml.ScalarNode:
return ee.evaluateScalarYamlNode(ctx, node)
case yaml.MappingNode:
return ee.evaluateMappingYamlNode(ctx, node)
case yaml.SequenceNode:
return ee.evaluateSequenceYamlNode(ctx, node)
default:
return nil, nil
}
}
func (ee expressionEvaluator) EvaluateYamlNode(ctx context.Context, node *yaml.Node) error {
ret, err := ee.evaluateYamlNodeInternal(ctx, node)
if err != nil {
return err
}
if ret != nil {
return ret.Decode(node)
}
return nil
}
func (ee expressionEvaluator) Interpolate(ctx context.Context, in string) string {
if !strings.Contains(in, "${{") || !strings.Contains(in, "}}") {
return in
}
expr, _ := rewriteSubExpression(ctx, in, true)
evaluated, err := ee.evaluate(ctx, expr, exprparser.DefaultStatusCheckNone)
if err != nil {
common.Logger(ctx).Errorf("Unable to interpolate expression '%s': %s", expr, err)
return ""
}
value, ok := evaluated.(string)
if !ok {
panic(fmt.Sprintf("Expression %s did not evaluate to a string", expr))
}
return value
}
// EvalBool evaluates an expression against given evaluator
func EvalBool(ctx context.Context, evaluator ExpressionEvaluator, expr string, defaultStatusCheck exprparser.DefaultStatusCheck) (bool, error) {
nextExpr, _ := rewriteSubExpression(ctx, expr, false)
evaluated, err := evaluator.evaluate(ctx, nextExpr, defaultStatusCheck)
if err != nil {
return false, err
}
return exprparser.IsTruthy(evaluated), nil
}
func escapeFormatString(in string) string {
return strings.ReplaceAll(strings.ReplaceAll(in, "{", "{{"), "}", "}}")
}
//nolint:gocyclo
func rewriteSubExpression(ctx context.Context, in string, forceFormat bool) (string, error) {
if !strings.Contains(in, "${{") || !strings.Contains(in, "}}") {
return in, nil
}
strPattern := regexp.MustCompile("(?:''|[^'])*'")
pos := 0
exprStart := -1
strStart := -1
var results []string
formatOut := ""
for pos < len(in) {
if strStart > -1 {
matches := strPattern.FindStringIndex(in[pos:])
if matches == nil {
panic("unclosed string.")
}
strStart = -1
pos += matches[1]
} else if exprStart > -1 {
exprEnd := strings.Index(in[pos:], "}}")
strStart = strings.Index(in[pos:], "'")
if exprEnd > -1 && strStart > -1 {
if exprEnd < strStart {
strStart = -1
} else {
exprEnd = -1
}
}
if exprEnd > -1 {
formatOut += fmt.Sprintf("{%d}", len(results))
results = append(results, strings.TrimSpace(in[exprStart:pos+exprEnd]))
pos += exprEnd + 2
exprStart = -1
} else if strStart > -1 {
pos += strStart + 1
} else {
panic("unclosed expression.")
}
} else {
exprStart = strings.Index(in[pos:], "${{")
if exprStart != -1 {
formatOut += escapeFormatString(in[pos : pos+exprStart])
exprStart = pos + exprStart + 3
pos = exprStart
} else {
formatOut += escapeFormatString(in[pos:])
pos = len(in)
}
}
}
if len(results) == 1 && formatOut == "{0}" && !forceFormat {
return in, nil
}
out := fmt.Sprintf("format('%s', %s)", strings.ReplaceAll(formatOut, "'", "''"), strings.Join(results, ", "))
if in != out {
common.Logger(ctx).Debugf("expression '%s' rewritten to '%s'", in, out)
}
return out, nil
}
//nolint:gocyclo
func getEvaluatorInputs(ctx context.Context, rc *RunContext, step step, ghc *model.GithubContext) map[string]interface{} {
inputs := map[string]interface{}{}
setupWorkflowInputs(ctx, &inputs, rc)
var env map[string]string
if step != nil {
env = *step.getEnv()
} else {
env = rc.GetEnv()
}
for k, v := range env {
if strings.HasPrefix(k, "INPUT_") {
inputs[strings.ToLower(strings.TrimPrefix(k, "INPUT_"))] = v
}
}
if ghc.EventName == "workflow_dispatch" {
config := rc.Run.Workflow.WorkflowDispatchConfig()
if config != nil && config.Inputs != nil {
for k, v := range config.Inputs {
value := nestedMapLookup(ghc.Event, "inputs", k)
if value == nil {
value = v.Default
}
if v.Type == "boolean" {
inputs[k] = value == "true"
} else {
inputs[k] = value
}
}
}
}
if ghc.EventName == "workflow_call" {
config := rc.Run.Workflow.WorkflowCallConfig()
if config != nil && config.Inputs != nil {
for k, v := range config.Inputs {
value := nestedMapLookup(ghc.Event, "inputs", k)
if value == nil {
value = v.Default
}
if v.Type == "boolean" {
inputs[k] = value == "true"
} else {
inputs[k] = value
}
}
}
}
return inputs
}
func setupWorkflowInputs(ctx context.Context, inputs *map[string]interface{}, rc *RunContext) {
if rc.caller != nil {
config := rc.Run.Workflow.WorkflowCallConfig()
for name, input := range config.Inputs {
value := rc.caller.runContext.Run.Job().With[name]
if value != nil {
if str, ok := value.(string); ok {
// evaluate using the calling RunContext (outside)
value = rc.caller.runContext.ExprEval.Interpolate(ctx, str)
}
}
if value == nil && config != nil && config.Inputs != nil {
value = input.Default
if rc.ExprEval != nil {
if str, ok := value.(string); ok {
// evaluate using the called RunContext (inside)
value = rc.ExprEval.Interpolate(ctx, str)
}
}
}
(*inputs)[name] = value
}
}
}
func getWorkflowSecrets(ctx context.Context, rc *RunContext) map[string]string {
if rc.caller != nil {
job := rc.caller.runContext.Run.Job()
secrets := job.Secrets()
if secrets == nil && job.InheritSecrets() {
secrets = rc.caller.runContext.Config.Secrets
}
if secrets == nil {
secrets = map[string]string{}
}
for k, v := range secrets {
secrets[k] = rc.caller.runContext.ExprEval.Interpolate(ctx, v)
}
return secrets
}
return rc.Config.Secrets
}
func getWorkflowVars(_ context.Context, rc *RunContext) map[string]string {
return rc.Config.Vars
}