use generic json/yaml parsing functions

Author: mattfenwick

pkg/cli/analyze.go

@@ -1,12 +1,11 @@
 package cli
 
 import (
-	"encoding/json"
 	"fmt"
+	collections "github.com/mattfenwick/collections/pkg"
 	"github.com/mattfenwick/cyclonus/pkg/connectivity/probe"
 	"github.com/mattfenwick/cyclonus/pkg/generator"
 	"github.com/mattfenwick/cyclonus/pkg/linter"
-	"io/ioutil"
 	"strings"
 
 	"github.com/mattfenwick/cyclonus/pkg/kube"
@@ -175,12 +174,9 @@ type QueryTargetPod struct {
 
 func QueryTargets(explainedPolicies *matcher.Policy, podPath string, pods []*QueryTargetPod) {
 	if podPath != "" {
-		var podsFromFile []*QueryTargetPod
-		bs, err := ioutil.ReadFile(podPath)
+		podsFromFile, err := utils.ParseJsonFromFile[[]*QueryTargetPod](podPath)
 		utils.DoOrDie(err)
-		err = json.Unmarshal(bs, &podsFromFile)
-		utils.DoOrDie(err)
-		pods = append(pods, podsFromFile...)
+		pods = append(pods, *podsFromFile...)
 	}
 
 	for _, pod := range pods {
@@ -213,16 +209,13 @@ func QueryTargetHelper(policies *matcher.Policy, pod *QueryTargetPod) (*matcher.
 }
 
 func QueryTraffic(explainedPolicies *matcher.Policy, trafficPath string) {
-	var allTraffics []*matcher.Traffic
 	if trafficPath == "" {
 		logrus.Fatalf("%+v", errors.Errorf("path to traffic file required for QueryTraffic command"))
 	}
-	allTrafficBytes, err := ioutil.ReadFile(trafficPath)
-	utils.DoOrDie(err)
-	err = json.Unmarshal(allTrafficBytes, &allTraffics)
+	allTraffics, err := utils.ParseJsonFromFile[[]*matcher.Traffic](trafficPath)
 	utils.DoOrDie(err)
 
-	for _, traffic := range allTraffics {
+	for _, traffic := range *allTraffics {
 		fmt.Printf("Traffic:\n%s\n", traffic.Table())
 
 		result := explainedPolicies.IsTrafficAllowed(traffic)
@@ -237,11 +230,8 @@ type SyntheticProbeConnectivityConfig struct {
 
 func ProbeSyntheticConnectivity(explainedPolicies *matcher.Policy, modelPath string, kubePods []v1.Pod, kubeNamespaces []v1.Namespace) {
 	if modelPath != "" {
-		bs, err := ioutil.ReadFile(modelPath)
-		utils.DoOrDie(errors.Wrapf(err, "unable to read file %s", modelPath))
-		config := &SyntheticProbeConnectivityConfig{}
-		err = json.Unmarshal(bs, &config)
-		utils.DoOrDie(errors.Wrapf(err, "unable to unmarshal json"))
+		config, err := utils.ParseJsonFromFile[SyntheticProbeConnectivityConfig](modelPath)
+		utils.DoOrDie(err)
 
 		jobBuilder := &probe.JobBuilder{TimeoutSeconds: 10}
 

pkg/cli/probe.go

@@ -8,11 +8,9 @@ import (
 	"github.com/mattfenwick/cyclonus/pkg/utils"
 	"github.com/pkg/errors"
 	"github.com/spf13/cobra"
-	"io/ioutil"
 	v1 "k8s.io/api/core/v1"
 	networkingv1 "k8s.io/api/networking/v1"
 	"k8s.io/apimachinery/pkg/util/intstr"
-	"sigs.k8s.io/yaml"
 	"strings"
 )
 
@@ -101,14 +99,9 @@ func RunProbeCommand(args *ProbeArgs) {
 	actions := []*generator.Action{generator.ReadNetworkPolicies(args.ServerNamespaces)}
 
 	if args.PolicyPath != "" {
-		policyBytes, err := ioutil.ReadFile(args.PolicyPath)
+		kubePolicy, err := utils.ParseYamlFromFile[networkingv1.NetworkPolicy](args.PolicyPath)
 		utils.DoOrDie(err)
-
-		var kubePolicy networkingv1.NetworkPolicy
-		err = yaml.Unmarshal(policyBytes, &kubePolicy)
-		utils.DoOrDie(err)
-
-		actions = append(actions, generator.CreatePolicy(&kubePolicy))
+		actions = append(actions, generator.CreatePolicy(kubePolicy))
 	}
 
 	printer := connectivity.Printer{

pkg/cli/utils.go

@@ -2,13 +2,12 @@ package cli
 
 import (
 	"github.com/mattfenwick/cyclonus/pkg/kube"
+	"github.com/mattfenwick/cyclonus/pkg/utils"
 	"github.com/pkg/errors"
 	log "github.com/sirupsen/logrus"
-	"io/ioutil"
 	networkingv1 "k8s.io/api/networking/v1"
 	"os"
 	"path/filepath"
-	"sigs.k8s.io/yaml"
 )
 
 func readPoliciesFromPath(policyPath string) ([]*networkingv1.NetworkPolicy, error) {
@@ -22,25 +21,23 @@ func readPoliciesFromPath(policyPath string) ([]*networkingv1.NetworkPolicy, err
 			return nil
 		}
 		log.Debugf("walking path %s", path)
-		bytes, err := ioutil.ReadFile(path)
+		bytes, err := utils.ReadFileBytes(path)
 		if err != nil {
-			return errors.Wrapf(err, "unable to read file %s", path)
+			return err
 		}
 
 		// try parsing a list first
-		var policies []*networkingv1.NetworkPolicy
-		err = yaml.Unmarshal(bytes, &policies)
+		policies, err := utils.ParseYaml[[]*networkingv1.NetworkPolicy](bytes)
 		if err == nil {
-			log.Debugf("parsed %d policies from %s", len(policies), path)
-			allPolicies = append(allPolicies, policies...)
+			log.Debugf("parsed %d policies from %s", len(*policies), path)
+			allPolicies = append(allPolicies, *policies...)
 			return nil
 		}
 
 		log.Debugf("failed to parse list from %s, falling back to parsing single policy", path)
-		var policy *networkingv1.NetworkPolicy
-		err = yaml.UnmarshalStrict(bytes, &policy)
+		policy, err := utils.ParseYamlStrict[networkingv1.NetworkPolicy](bytes)
 		if err != nil {
-			return errors.Wrapf(err, "unable to unmarshal single policy from yaml at %s", path)
+			return errors.WithMessagef(err, "unable to parse single policy from yaml at %s", path)
 		}
 
 		log.Debugf("parsed single policy from %s: %+v", path, policy)

pkg/matcher/policy_tests.go

@@ -6,11 +6,10 @@ import (
 	. "github.com/onsi/gomega"
 	v1 "k8s.io/api/core/v1"
 	networkingv1 "k8s.io/api/networking/v1"
-	"sigs.k8s.io/yaml"
 )
 
 func RunPolicyTests() {
-	allowAllOnSCTPSerialized := `
+	allowAllOnSCTPSerializedYaml := `
 apiVersion: networking.k8s.io/v1
 kind: NetworkPolicy
 metadata:
@@ -23,10 +22,9 @@ spec:
   podSelector: {}
   policyTypes:
   - Ingress`
-	var kubePolicy *networkingv1.NetworkPolicy
-	err := yaml.Unmarshal([]byte(allowAllOnSCTPSerialized), &kubePolicy)
+	allowAllOnSCTPSerializedPolicy, err := utils.ParseYaml[networkingv1.NetworkPolicy]([]byte(allowAllOnSCTPSerializedYaml))
 	utils.DoOrDie(err)
-	allowAllOnSCTP := BuildNetworkPolicies(true, []*networkingv1.NetworkPolicy{kubePolicy})
+	allowAllOnSCTP := BuildNetworkPolicies(true, []*networkingv1.NetworkPolicy{allowAllOnSCTPSerializedPolicy})
 
 	Describe("Allowing a protocol should implicitly deny other protocols from pods", func() {
 		It("should not allow TCP", func() {
@@ -125,7 +123,7 @@ spec:
 	})
 
 	Describe("Policy allowing egress to ips", func() {
-		allowAllOnSCTPSerialized := `
+		policyYaml := `
 apiVersion: networking.k8s.io/v1
 kind: NetworkPolicy
 metadata:
@@ -149,8 +147,7 @@ spec:
       pod: a
   policyTypes:
   - Egress`
-		var kubePolicy *networkingv1.NetworkPolicy
-		err := yaml.Unmarshal([]byte(allowAllOnSCTPSerialized), &kubePolicy)
+		kubePolicy, err := utils.ParseYaml[networkingv1.NetworkPolicy]([]byte(policyYaml))
 		utils.DoOrDie(err)
 		policy := BuildNetworkPolicies(true, []*networkingv1.NetworkPolicy{kubePolicy})
 
@@ -196,8 +193,7 @@ spec:
       pod: a
   policyTypes:
   - Ingress`
-		var kubePolicy *networkingv1.NetworkPolicy
-		err := yaml.Unmarshal([]byte(policyYaml), &kubePolicy)
+		kubePolicy, err := utils.ParseYaml[networkingv1.NetworkPolicy]([]byte(policyYaml))
 		utils.DoOrDie(err)
 		policy := BuildNetworkPolicies(true, []*networkingv1.NetworkPolicy{kubePolicy})
 

pkg/recipes/recipe.go

@@ -9,7 +9,6 @@ import (
 	v1 "k8s.io/api/core/v1"
 	networkingv1 "k8s.io/api/networking/v1"
 	"k8s.io/apimachinery/pkg/util/intstr"
-	"sigs.k8s.io/yaml"
 )
 
 type Recipe struct {
@@ -22,10 +21,9 @@ type Recipe struct {
 func (r *Recipe) Policies() []*networkingv1.NetworkPolicy {
 	var policies []*networkingv1.NetworkPolicy
 	for _, yamlString := range r.PolicyYamls {
-		netpol := networkingv1.NetworkPolicy{}
-		err := yaml.Unmarshal([]byte(yamlString), &netpol)
+		netpol, err := utils.ParseYaml[networkingv1.NetworkPolicy]([]byte(yamlString))
 		utils.DoOrDie(err)
-		policies = append(policies, &netpol)
+		policies = append(policies, netpol)
 	}
 	return policies
 }