From adca01c1d40f48edfbd77a0ea72481c3adf0ad63 Mon Sep 17 00:00:00 2001
From: Nick Nellis <nick.nellis@solo.io>
Date: Tue, 6 Jul 2021 09:47:24 -0500
Subject: [PATCH] added seed to labels

---
 README.md                                    | 17 +++++++++++++++++
 pkg/generate/assets/app.yaml.tmpl            |  5 +++++
 pkg/generate/assets/gateway.yaml.tmpl        |  3 +++
 pkg/generate/assets/serviceentry.yaml.tmpl   |  3 +++
 pkg/generate/assets/virtualservice.yaml.tmpl |  3 +++
 pkg/generate/const.go                        |  1 -
 pkg/generate/gen.go                          |  8 ++++----
 pkg/generate/model.go                        |  5 +++--
 8 files changed, 38 insertions(+), 7 deletions(-)

diff --git a/README.md b/README.md
index f6cc3f6..bf648b3 100644
--- a/README.md
+++ b/README.md
@@ -60,6 +60,23 @@ generate [flags]
   --app-error-percent 0.25
 ```
 
+* Recreating an output - there are times you might want to recreate a users setup. All assets are labeled with a seed value. simply use the seed in your cmd
+```shell
+# Example namespace
+# apiVersion: v1
+# kind: Namespace
+# metadata:
+#   name: ns-1
+#   labels:
+#     istio-injection: enabled
+#     seed: "1625582727962871000"
+
+./istio-app-simulator generate \
+  # use the seed above to regenerate the same output
+  --seed 1625582727962871000
+```
+
+
 ### Fake Service UI
 You can reach a UI for the fake service call stack by using kubernetes port forwarding to the tier 1 service in the namespace
 ```shell
diff --git a/pkg/generate/assets/app.yaml.tmpl b/pkg/generate/assets/app.yaml.tmpl
index bb219ec..a9035fb 100644
--- a/pkg/generate/assets/app.yaml.tmpl
+++ b/pkg/generate/assets/app.yaml.tmpl
@@ -1,3 +1,4 @@
+{{ $seed := .Seed }}
 {{range $namespace,$microservices := .Microservices}}
 ---
 apiVersion: v1
@@ -6,6 +7,7 @@ metadata:
   name: {{$namespace}}
   labels:
     istio-injection: enabled
+    seed: "{{ $seed }}"
 ---
 {{range $microservice := $microservices}}
 apiVersion: v1
@@ -16,6 +18,7 @@ metadata:
   labels:
     app: {{$microservice.Name}}
     tier: "{{$microservice.Tier}}"
+    seed: "{{ $seed }}"
 ---
 apiVersion: v1
 kind: Service
@@ -25,6 +28,7 @@ metadata:
   labels:
     app: {{$microservice.Name}}
     tier: "{{$microservice.Tier}}"
+    seed: "{{ $seed }}"
 spec:
   selector:
     app: {{$microservice.Name}}
@@ -44,6 +48,7 @@ metadata:
     app: {{$microservice.Name}}
     version: {{$version}}
     tier: "{{$microservice.Tier}}"
+    seed: "{{ $seed }}"
 spec:
   replicas: 1
   selector:
diff --git a/pkg/generate/assets/gateway.yaml.tmpl b/pkg/generate/assets/gateway.yaml.tmpl
index 59fb56a..28a3625 100644
--- a/pkg/generate/assets/gateway.yaml.tmpl
+++ b/pkg/generate/assets/gateway.yaml.tmpl
@@ -1,9 +1,12 @@
+{{ $seed := .Seed }}
 ---
 apiVersion: networking.istio.io/v1beta1
 kind: Gateway
 metadata:
   name: istio-ingressgateway
   namespace: istio-system
+  labels:
+    seed: "{{ $seed }}"
 spec:
   selector:
     istio: ingressgateway
diff --git a/pkg/generate/assets/serviceentry.yaml.tmpl b/pkg/generate/assets/serviceentry.yaml.tmpl
index 70cd119..b38ce89 100644
--- a/pkg/generate/assets/serviceentry.yaml.tmpl
+++ b/pkg/generate/assets/serviceentry.yaml.tmpl
@@ -1,9 +1,12 @@
+{{ $seed := .Seed }}
 {{- range $service := .ExternalServices }}
 apiVersion: networking.istio.io/v1alpha3
 kind: ServiceEntry
 metadata:
   name: {{ $service }}
   namespace: istio-system
+  labels:
+    seed: "{{ $seed }}"
 spec:
   hosts:
   - {{ $service }}
diff --git a/pkg/generate/assets/virtualservice.yaml.tmpl b/pkg/generate/assets/virtualservice.yaml.tmpl
index 3efc488..614ccde 100644
--- a/pkg/generate/assets/virtualservice.yaml.tmpl
+++ b/pkg/generate/assets/virtualservice.yaml.tmpl
@@ -1,9 +1,12 @@
+{{ $seed := .Seed }}
 ---
 apiVersion: networking.istio.io/v1beta1
 kind: VirtualService
 metadata:
   name: ingress-gw
   namespace: istio-system
+  labels:
+    seed: "{{ $seed }}"
 spec:
   hosts:
     - "{{- .Host }}"
diff --git a/pkg/generate/const.go b/pkg/generate/const.go
index 2467a38..e115f2b 100644
--- a/pkg/generate/const.go
+++ b/pkg/generate/const.go
@@ -1,6 +1,5 @@
 package generate
 
-
 const (
 	maxAmountOfVersions = 3
 )
diff --git a/pkg/generate/gen.go b/pkg/generate/gen.go
index ee0d9bb..6b36351 100644
--- a/pkg/generate/gen.go
+++ b/pkg/generate/gen.go
@@ -27,13 +27,12 @@ func NewAppGenerator(config *Config) *AppGenerator {
 
 func (a *AppGenerator) Generate() error {
 
-	seed := a.config.Seed
 	// if unset, make random
-	if seed == 0 {
-		seed = time.Now().UnixNano()
+	if a.config.Seed == 0 {
+		a.config.Seed = time.Now().UnixNano()
 	}
 
-	rand.Seed(seed)
+	rand.Seed(a.config.Seed)
 	// generate namespaces
 	// namespace names will be very simple ns1, ns2 etc
 	var microservices []*Microservice
@@ -149,6 +148,7 @@ func (a *AppGenerator) render(microservices map[string][]*Microservice) {
 		Microservices:    microservices,
 		ExternalServices: externalServices,
 		Host:             a.config.Hostname,
+		Seed:             a.config.Seed,
 	}
 
 	gatewayFile, err := os.Create(a.config.OutputDir + "/gateway.yaml")
diff --git a/pkg/generate/model.go b/pkg/generate/model.go
index d5204d7..ad3fa3c 100644
--- a/pkg/generate/model.go
+++ b/pkg/generate/model.go
@@ -27,9 +27,10 @@ type Backend struct {
 }
 
 type TemplateConfig struct {
-	Microservices map[string][]*Microservice
+	Microservices    map[string][]*Microservice
 	ExternalServices []string
-	Host string
+	Host             string
+	Seed             int64
 }
 
 type Config struct {