feat: operator render template vars in the env vars, e.g. process_type

operator/pkg/controllers/bkapp/common/env_vars.go

@@ -20,7 +20,9 @@ package common
 
 import (
 	"sort"
+	"strings"
 
+	"github.com/samber/lo"
 	corev1 "k8s.io/api/core/v1"
 
 	paasv1alpha2 "bk.tencent.com/paas-app-operator/api/v1alpha2"
@@ -37,3 +39,33 @@ func GetAppEnvs(bkapp *paasv1alpha2.BkApp) []corev1.EnvVar {
 	sort.Slice(envs, func(i, j int) bool { return envs[i].Name < envs[j].Name })
 	return envs
 }
+
+// VarsRenderContext is the context object for rendering variables list
+type VarsRenderContext struct {
+	// ProcessType is the type of the process, e.g. "web", "worker"
+	ProcessType string
+}
+
+// RenderAppVars render a list of env variables, it replaces var template with their
+// actual values. Only a limited set of vars are supported, including:
+//
+// - {{bk_var_process_type}} -> real process type
+func RenderAppVars(vars []corev1.EnvVar, context VarsRenderContext) []corev1.EnvVar {
+	supportedKeySuffixes := []string{"_LOG_NAME_PREFIX", "_PROCESS_TYPE"}
+
+	results := make([]corev1.EnvVar, len(vars))
+	for i, v := range vars {
+		newValue := v.Value
+		// Only do the rendering if the key ends with any supported suffix to prevent
+		// unnecessary rendering.
+		if lo.SomeBy(supportedKeySuffixes, func(suffix string) bool {
+			return strings.HasSuffix(v.Name, suffix)
+		}) {
+			// TODO: Use other method to replace the variables when more variables are supported
+			newValue = strings.Replace(newValue, "{{bk_var_process_type}}", context.ProcessType, -1)
+		}
+
+		results[i] = corev1.EnvVar{Name: v.Name, Value: newValue}
+	}
+	return results
+}

operator/pkg/controllers/bkapp/common/env_vars_test.go

@@ -21,6 +21,7 @@ package common
 import (
 	. "github.com/onsi/ginkgo/v2"
 	. "github.com/onsi/gomega"
+	corev1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 
 	paasv1alpha2 "bk.tencent.com/paas-app-operator/api/v1alpha2"
@@ -66,3 +67,38 @@ var _ = Describe("Get App Envs", func() {
 		Expect(len(envs)).To(Equal(0))
 	})
 })
+
+var _ = Describe("Get App Envs", func() {
+	It("No \"bk-var-*\" vars in the value", func() {
+		envs := []corev1.EnvVar{
+			{Name: "FOO", Value: "some random value foo"},
+			{Name: "BAR", Value: "some random value bar"},
+		}
+		renderedVars := RenderAppVars(envs, VarsRenderContext{ProcessType: "web"})
+
+		By("The rendered vars should be the same as the input vars")
+		Expect(renderedVars).To(Equal(envs))
+	})
+
+	It("Contains supported vars", func() {
+		envs := []corev1.EnvVar{
+			{Name: "BKPAAS_PROCESS_TYPE", Value: "{{bk_var_process_type}}"},
+			{Name: "OTHER_PRE_LOG_NAME_PREFIX", Value: "foo-{{bk_var_process_type}}"},
+			// with valid name but variable does not match
+			{Name: "OTHER_PRE_PROCESS_TYPE", Value: "{{another_var}}"},
+			{Name: "FOO", Value: "some random value foo"},
+			// the variable matches but the name is not in whitelist
+			{Name: "BAR", Value: "{{bk_var_process_type}}"},
+		}
+		renderedVars := RenderAppVars(envs, VarsRenderContext{ProcessType: "web"})
+
+		By("The `process_type` should be rendered properly.")
+		Expect(renderedVars).To(Equal([]corev1.EnvVar{
+			{Name: "BKPAAS_PROCESS_TYPE", Value: "web"},
+			{Name: "OTHER_PRE_LOG_NAME_PREFIX", Value: "foo-web"},
+			{Name: "OTHER_PRE_PROCESS_TYPE", Value: "{{another_var}}"},
+			{Name: "FOO", Value: "some random value foo"},
+			{Name: "BAR", Value: "{{bk_var_process_type}}"},
+		}))
+	})
+})

operator/pkg/controllers/bkapp/hooks/resources/hooks.go

@@ -122,6 +122,11 @@ func BuildPreReleaseHook(bkapp *paasv1alpha2.BkApp, status *paasv1alpha2.HookSta
 		command = append([]string{"launcher"}, command...)
 	}
 
+	// Generate the environment variables and render the "{{bk_var_*}}" var placeholder which
+	// might be used in the values.
+	envVars := common.GetAppEnvs(bkapp)
+	envVars = common.RenderAppVars(envVars, common.VarsRenderContext{ProcessType: "sys-pre-rel"})
+
 	return &HookInstance{
 		Pod: &corev1.Pod{
 			TypeMeta: metav1.TypeMeta{
@@ -146,7 +151,7 @@ func BuildPreReleaseHook(bkapp *paasv1alpha2.BkApp, status *paasv1alpha2.HookSta
 						Image:           bkapp.Spec.Build.Image,
 						Command:         kubeutil.ReplaceCommandEnvVariables(command),
 						Args:            kubeutil.ReplaceCommandEnvVariables(args),
-						Env:             common.GetAppEnvs(bkapp),
+						Env:             envVars,
 						Name:            "hook",
 						ImagePullPolicy: bkapp.Spec.Build.ImagePullPolicy,
 						// pre-hook 使用默认资源配置

operator/pkg/controllers/bkapp/processes/resources/deployment.go

@@ -62,8 +62,11 @@ func BuildProcDeployment(app *paasv1alpha2.BkApp, procName string) (*appsv1.Depl
 		deployID = DefaultDeployID
 	}
 
-	// Prepare data
+	// Generate the environment variables and render the "{{bk_var_*}}" var placeholder which
+	// might be used in the values.
 	envVars := common.GetAppEnvs(app)
+	envVars = common.RenderAppVars(envVars, common.VarsRenderContext{ProcessType: procName})
+
 	mounterMap, err := volumes.GetAllVolumeMounterMap(app)
 	if err != nil {
 		return nil, err