Ability to use sprig functions in analyzer templates (#1745)

* Ability to use sprig functions in analyzer templates

Author: sgalsaleh

internal/util/util.go

@@ -11,6 +11,7 @@ import (
 	"strings"
 	"text/template"
 
+	"github.com/Masterminds/sprig/v3"
 	"golang.org/x/text/cases"
 	"golang.org/x/text/language"
 )
@@ -94,7 +95,7 @@ func IsInCluster() bool {
 // RenderTemplate renders a template and returns the result as a string
 func RenderTemplate(tpl string, data interface{}) (string, error) {
 	// Create a new template and parse the letter into it
-	t, err := template.New("data").Parse(tpl)
+	t, err := template.New("data").Funcs(sprig.FuncMap()).Parse(tpl)
 	if err != nil {
 		return "", err
 	}

internal/util/util_test.go

@@ -284,6 +284,20 @@ func TestRenderTemplate(t *testing.T) {
 			want:    "Hello, <no value>!",
 			wantErr: false,
 		},
+		{
+			name:    "template with sprig function works",
+			tpl:     "{{ \"hello \" | upper }}{{ .Name }}",
+			data:    map[string]string{"Name": "World"},
+			want:    "HELLO World",
+			wantErr: false,
+		},
+		{
+			name:    "template with undefined sprig function errors",
+			tpl:     "{{ \"hello \" | upp }}{{ .Name }}",
+			data:    map[string]string{"Name": "World"},
+			want:    "",
+			wantErr: true,
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {

pkg/analyze/cluster_container_statuses.go

@@ -1,15 +1,14 @@
 package analyzer
 
 import (
-	"bytes"
 	"encoding/json"
 	"fmt"
 	"path/filepath"
 	"slices"
 	"strings"
-	"text/template"
 
 	"github.com/pkg/errors"
+	"github.com/replicatedhq/troubleshoot/internal/util"
 	troubleshootv1beta2 "github.com/replicatedhq/troubleshoot/pkg/apis/troubleshoot/v1beta2"
 	"github.com/replicatedhq/troubleshoot/pkg/constants"
 	corev1 "k8s.io/api/core/v1"
@@ -240,21 +239,14 @@ func renderContainerMessage(message string, info *matchedContainerInfo) string {
 	if info == nil {
 		return message
 	}
-	out := fmt.Sprintf("Container matched. Container: %s, Namespace: %s, Pod: %s", info.ContainerName, info.Namespace, info.PodName)
 
-	tmpl := template.New("container")
-	msgTmpl, err := tmpl.Parse(message)
-	if err != nil {
-		klog.V(2).Infof("failed to parse message template: %v", err)
-		return out
-	}
+	out := fmt.Sprintf("Container matched. Container: %s, Namespace: %s, Pod: %s", info.ContainerName, info.Namespace, info.PodName)
 
-	var m bytes.Buffer
-	err = msgTmpl.Execute(&m, info)
+	renderedMsg, err := util.RenderTemplate(message, info)
 	if err != nil {
 		klog.V(2).Infof("failed to render message template: %v", err)
 		return out
 	}
 
-	return strings.TrimSpace(m.String())
+	return strings.TrimSpace(renderedMsg)
 }

pkg/analyze/cluster_pod_statuses.go

@@ -1,14 +1,13 @@
 package analyzer
 
 import (
-	"bytes"
 	"encoding/json"
 	"fmt"
 	"path/filepath"
 	"strings"
-	"text/template"
 
 	"github.com/pkg/errors"
+	"github.com/replicatedhq/troubleshoot/internal/util"
 	troubleshootv1beta2 "github.com/replicatedhq/troubleshoot/pkg/apis/troubleshoot/v1beta2"
 	"github.com/replicatedhq/troubleshoot/pkg/constants"
 	"github.com/replicatedhq/troubleshoot/pkg/k8sutil"
@@ -190,31 +189,19 @@ func clusterPodStatuses(analyzer *troubleshootv1beta2.ClusterPodStatuses, getChi
 				pod.Status.Message = "None"
 			}
 
-			tmpl := template.New("pod")
-
 			// template the title
-			titleTmpl, err := tmpl.Parse(r.Title)
-			if err != nil {
-				return nil, errors.Wrap(err, "failed to create new title template")
-			}
-			var t bytes.Buffer
-			err = titleTmpl.Execute(&t, pod)
+			renderedTitle, err := util.RenderTemplate(r.Title, pod)
 			if err != nil {
-				return nil, errors.Wrap(err, "failed to execute template")
+				return nil, errors.Wrap(err, "failed to render template")
 			}
-			r.Title = t.String()
+			r.Title = renderedTitle
 
 			// template the message
-			msgTmpl, err := tmpl.Parse(r.Message)
+			renderedMsg, err := util.RenderTemplate(r.Message, pod)
 			if err != nil {
 				return nil, errors.Wrap(err, "failed to create new title template")
 			}
-			var m bytes.Buffer
-			err = msgTmpl.Execute(&m, pod)
-			if err != nil {
-				return nil, errors.Wrap(err, "failed to execute template")
-			}
-			r.Message = strings.TrimSpace(m.String())
+			r.Message = strings.TrimSpace(renderedMsg)
 
 			// add to results, break and check the next pod
 			allResults = append(allResults, &r)

pkg/analyze/event.go

@@ -1,16 +1,15 @@
 package analyzer
 
 import (
-	"bytes"
 	"encoding/json"
 	"fmt"
 	"path"
 	"regexp"
 	"strconv"
 	"strings"
-	"text/template"
 
 	"github.com/pkg/errors"
+	"github.com/replicatedhq/troubleshoot/internal/util"
 	troubleshootv1beta2 "github.com/replicatedhq/troubleshoot/pkg/apis/troubleshoot/v1beta2"
 	"github.com/replicatedhq/troubleshoot/pkg/constants"
 	corev1 "k8s.io/api/core/v1"
@@ -198,21 +197,14 @@ func decorateMessage(message string, event *corev1.Event) string {
 	if event == nil {
 		return message
 	}
+
 	out := fmt.Sprintf("Event matched. Reason: %s Name: %s Message: %s", event.Reason, event.InvolvedObject.Name, event.Message)
 
-	tmpl := template.New("event")
-	msgTmpl, err := tmpl.Parse(message)
+	renderedMsg, err := util.RenderTemplate(message, event)
 	if err != nil {
 		klog.V(2).Infof("failed to parse message template: %v", err)
 		return out
 	}
 
-	var m bytes.Buffer
-	err = msgTmpl.Execute(&m, event)
-	if err != nil {
-		klog.V(2).Infof("failed to render message template: %v", err)
-		return out
-	}
-
-	return strings.TrimSpace(m.String())
+	return strings.TrimSpace(renderedMsg)
 }

pkg/analyze/host_filesystem_performance.go

@@ -1,15 +1,14 @@
 package analyzer
 
 import (
-	"bytes"
 	"encoding/json"
 	"fmt"
 	"log"
 	"strings"
-	"text/template"
 	"time"
 
 	"github.com/pkg/errors"
+	"github.com/replicatedhq/troubleshoot/internal/util"
 	troubleshootv1beta2 "github.com/replicatedhq/troubleshoot/pkg/apis/troubleshoot/v1beta2"
 	"github.com/replicatedhq/troubleshoot/pkg/collect"
 )
@@ -171,18 +170,12 @@ func doCompareHostFilesystemPerformance(operator string, actual time.Duration, d
 }
 
 func renderFSPerfOutcome(outcome string, fsPerf collect.FSPerfResults) string {
-	t, err := template.New("").Parse(outcome)
-	if err != nil {
-		log.Printf("Failed to parse filesystem performance outcome: %v", err)
-		return outcome
-	}
-	var buf bytes.Buffer
-	err = t.Execute(&buf, fsPerf)
+	rendered, err := util.RenderTemplate(outcome, fsPerf)
 	if err != nil {
 		log.Printf("Failed to render filesystem performance outcome: %v", err)
 		return outcome
 	}
-	return buf.String()
+	return rendered
 }
 
 func (a *AnalyzeHostFilesystemPerformance) analyzeSingleNode(content collectedContent, currentTitle string) ([]*AnalyzeResult, error) {

pkg/analyze/host_system_packages.go

@@ -9,9 +9,8 @@ import (
 	"strings"
 	"unicode"
 
-	"text/template"
-
 	"github.com/pkg/errors"
+	"github.com/replicatedhq/troubleshoot/internal/util"
 	troubleshootv1beta2 "github.com/replicatedhq/troubleshoot/pkg/apis/troubleshoot/v1beta2"
 	"github.com/replicatedhq/troubleshoot/pkg/collect"
 )
@@ -158,20 +157,12 @@ func compareSystemPackagesConditionalToActual(conditional string, templateMap ma
 		return true, nil
 	}
 
-	tmpl := template.New("conditional")
-
-	conditionalTmpl, err := tmpl.Parse(conditional)
-	if err != nil {
-		return false, errors.Wrap(err, "failed to create new when template")
-	}
-
-	var when bytes.Buffer
-	err = conditionalTmpl.Execute(&when, templateMap)
+	when, err := util.RenderTemplate(conditional, templateMap)
 	if err != nil {
-		return false, errors.Wrap(err, "failed to execute when template")
+		return false, errors.Wrap(err, "failed to render when template")
 	}
 
-	t, err := strconv.ParseBool(when.String())
+	t, err := strconv.ParseBool(when)
 	if err != nil {
 		return false, errors.Wrap(err, "failed to parse templated when expression as a boolean")
 	}
@@ -223,21 +214,14 @@ func (a *AnalyzeHostSystemPackages) analyzeSingleNode(content collectedContent,
 				continue
 			}
 
-			tmpl := template.New("package")
-
 			r.Title = currentTitle
 
 			// template the message
-			msgTmpl, err := tmpl.Parse(r.Message)
+			renderedMsg, err := util.RenderTemplate(r.Message, templateMap)
 			if err != nil {
 				return nil, errors.Wrap(err, "failed to create new message template")
 			}
-			var m bytes.Buffer
-			err = msgTmpl.Execute(&m, templateMap)
-			if err != nil {
-				return nil, errors.Wrap(err, "failed to execute message template")
-			}
-			r.Message = m.String()
+			r.Message = renderedMsg
 
 			// add to results, break and check the next pod
 			allResults = append(allResults, &r)

pkg/analyze/k8s_node_metrics.go

@@ -1,16 +1,15 @@
 package analyzer
 
 import (
-	"bytes"
 	"encoding/json"
 	"fmt"
 	"path/filepath"
 	"regexp"
 	"strconv"
 	"strings"
-	"text/template"
 
 	"github.com/pkg/errors"
+	"github.com/replicatedhq/troubleshoot/internal/util"
 	troubleshootv1beta2 "github.com/replicatedhq/troubleshoot/pkg/apis/troubleshoot/v1beta2"
 	"k8s.io/klog/v2"
 	kubeletv1alpha1 "k8s.io/kubelet/pkg/apis/stats/v1alpha1"
@@ -299,18 +298,11 @@ func renderTemplate(tmpMsg string, data any) string {
 		return tmpMsg
 	}
 
-	t, err := template.New("msg").Parse(tmpMsg)
+	rendered, err := util.RenderTemplate(tmpMsg, data)
 	if err != nil {
-		klog.V(2).Infof("Failed to parse template: %s", err)
+		klog.V(2).Infof("Failed to render template: %s", err)
 		return tmpMsg
 	}
 
-	var m bytes.Buffer
-	err = t.Execute(&m, data)
-	if err != nil {
-		klog.V(2).Infof("Failed to execute template: %s", err)
-		return tmpMsg
-	}
-
-	return m.String()
+	return rendered
 }

pkg/analyze/text_analyze.go

@@ -1,15 +1,14 @@
 package analyzer
 
 import (
-	"bytes"
 	"fmt"
 	"path/filepath"
 	"regexp"
 	"strconv"
 	"strings"
-	"text/template"
 
 	"github.com/pkg/errors"
+	"github.com/replicatedhq/troubleshoot/internal/util"
 	troubleshootv1beta2 "github.com/replicatedhq/troubleshoot/pkg/apis/troubleshoot/v1beta2"
 )
 
@@ -210,7 +209,7 @@ func analyzeRegexGroups(pattern string, collected []byte, outcomes []*troublesho
 
 			if isMatch {
 				result.IsFail = true
-				tplMessage, err := templateRegExGroup(outcome.Fail.Message, foundMatches)
+				tplMessage, err := util.RenderTemplate(outcome.Fail.Message, foundMatches)
 				if err != nil {
 					return result, errors.Wrap(err, "failed to template message in outcome.Fail block")
 				}
@@ -227,7 +226,7 @@ func analyzeRegexGroups(pattern string, collected []byte, outcomes []*troublesho
 
 			if isMatch {
 				result.IsWarn = true
-				tplMessage, err := templateRegExGroup(outcome.Warn.Message, foundMatches)
+				tplMessage, err := util.RenderTemplate(outcome.Warn.Message, foundMatches)
 				if err != nil {
 					return result, errors.Wrap(err, "failed to template message in outcome.Warn block")
 				}
@@ -244,7 +243,7 @@ func analyzeRegexGroups(pattern string, collected []byte, outcomes []*troublesho
 
 			if isMatch {
 				result.IsPass = true
-				tplMessage, err := templateRegExGroup(outcome.Pass.Message, foundMatches)
+				tplMessage, err := util.RenderTemplate(outcome.Pass.Message, foundMatches)
 				if err != nil {
 					return result, errors.Wrap(err, "failed to template message in outcome.Pass block")
 				}
@@ -259,20 +258,6 @@ func analyzeRegexGroups(pattern string, collected []byte, outcomes []*troublesho
 	return result, nil
 }
 
-// templateRegExGroup takes a tpl and replaces the variables using matches.
-func templateRegExGroup(tpl string, matches map[string]string) (string, error) {
-	t, err := template.New("").Parse(tpl)
-	if err != nil {
-		return "", err
-	}
-	var msg bytes.Buffer
-	err = t.Execute(&msg, matches)
-	if err != nil {
-		return "", err
-	}
-	return msg.String(), nil
-}
-
 func compareRegex(conditional string, foundMatches map[string]string) (bool, error) {
 	if conditional == "" {
 		return true, nil
@@ -287,6 +272,11 @@ func compareRegex(conditional string, foundMatches map[string]string) (bool, err
 	operator := parts[1]
 	lookForValue := parts[2]
 
+	// handle empty strings
+	if lookForValue == "''" || lookForValue == `""` {
+		lookForValue = ""
+	}
+
 	foundValue, ok := foundMatches[lookForMatchName]
 	if !ok {
 		// not an error, just wasn't matched