Adding Istio

simple-microservices/department-service/k8s/deployment.yaml

@@ -1,21 +1,64 @@
 apiVersion: apps/v1
 kind: Deployment
 metadata:
-  name: department-deployment
+  name: department-deployment-v1
 spec:
   selector:
     matchLabels:
       app: department
+      version: v1
   template:
     metadata:
       labels:
         app: department
+        version: v1
     spec:
       containers:
       - name: department
         image: piomin/department-service
         ports:
         - containerPort: 8080
+        volumeMounts:
+          - mountPath: /etc/podinfo
+            name: podinfo
+      volumes:
+        - name: podinfo
+          downwardAPI:
+            items:
+              - path: "labels"
+                fieldRef:
+                  fieldPath: metadata.labels
+---
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: department-deployment-v2
+spec:
+  selector:
+    matchLabels:
+      app: department
+      version: v2
+  template:
+    metadata:
+      labels:
+        app: department
+        version: v2
+    spec:
+      containers:
+        - name: department
+          image: piomin/department-service
+          ports:
+            - containerPort: 8080
+          volumeMounts:
+            - mountPath: /etc/podinfo
+              name: podinfo
+      volumes:
+        - name: podinfo
+          downwardAPI:
+            items:
+              - path: "labels"
+                fieldRef:
+                  fieldPath: metadata.labels
 ---
 apiVersion: v1
 kind: Service

simple-microservices/department-service/k8s/istio.yaml

@@ -0,0 +1,42 @@
+apiVersion: networking.istio.io/v1beta1
+kind: DestinationRule
+metadata:
+  name: department-service-destination
+spec:
+  host: department-service.default.svc.cluster.local
+  subsets:
+    - name: v1
+      labels:
+        version: v1
+    - name: v2
+      labels:
+        version: v2
+---
+apiVersion: networking.istio.io/v1beta1
+kind: VirtualService
+metadata:
+  name: department-service-route
+spec:
+  hosts:
+    - department-service.default.svc.cluster.local
+  http:
+    - match:
+        - headers:
+            X-Version:
+              exact: v1
+      route:
+        - destination:
+            host: department-service.default.svc.cluster.local
+            subset: v1
+    - match:
+        - headers:
+            X-Version:
+              exact: v2
+      route:
+        - destination:
+            host: department-service.default.svc.cluster.local
+            subset: v2
+    - route:
+        - destination:
+            host: department-service.default.svc.cluster.local
+            subset: v1

simple-microservices/department-service/src/main/kotlin/pl/piomin/samples/kubernetes/department/DepartmentApp.kt

@@ -1,18 +1,24 @@
 package pl.piomin.samples.kubernetes.department
 
+import org.springframework.beans.factory.annotation.Autowired
 import org.springframework.boot.autoconfigure.SpringBootApplication
 import org.springframework.boot.runApplication
 import org.springframework.boot.web.client.RestTemplateBuilder
 import org.springframework.context.annotation.Bean
 import org.springframework.web.client.RestTemplate
+import pl.piomin.samples.kubernetes.department.interceptor.RestTemplateInterceptor
 import java.time.Duration
 
 @SpringBootApplication
 class DepartmentApp {
 
+    @Autowired
+    lateinit var interceptor: RestTemplateInterceptor
+
     @Bean
     fun restTemplate(): RestTemplate =
             RestTemplateBuilder()
+                    .interceptors(interceptor)
                     .setReadTimeout(Duration.ofMillis(1000L))
                     .build()
 }

simple-microservices/department-service/src/main/kotlin/pl/piomin/samples/kubernetes/department/interceptor/RestTemplateInterceptor.kt

@@ -0,0 +1,20 @@
+package pl.piomin.samples.kubernetes.department.interceptor
+
+import org.springframework.http.HttpRequest
+import org.springframework.http.client.ClientHttpRequestExecution
+import org.springframework.http.client.ClientHttpRequestInterceptor
+import org.springframework.http.client.ClientHttpResponse
+import org.springframework.stereotype.Component
+import pl.piomin.samples.kubernetes.department.service.AppVersion
+
+@Component
+class RestTemplateInterceptor(val appVersion: AppVersion): ClientHttpRequestInterceptor {
+
+    override fun intercept(req: HttpRequest,
+                           body: ByteArray,
+                           execution: ClientHttpRequestExecution): ClientHttpResponse {
+        req.headers.add("X-Version", appVersion.getVersion())
+        return execution.execute(req, body)
+    }
+
+}

simple-microservices/department-service/src/main/kotlin/pl/piomin/samples/kubernetes/department/service/AppVersion.kt

@@ -0,0 +1,16 @@
+package pl.piomin.samples.kubernetes.department.service
+
+import org.springframework.stereotype.Service
+import java.io.File
+
+@Service
+class AppVersion {
+
+    fun getVersion(): String? {
+        val file = File("/etc/podinfo/labels")
+        return if(file.exists()) {
+            file.readLines().first{ it.startsWith("version=")}
+                    .split("=")[1]
+        } else null
+    }
+}

simple-microservices/employee-service/k8s/deployment.yaml

@@ -1,21 +1,64 @@
 apiVersion: apps/v1
 kind: Deployment
 metadata:
-  name: employee-deployment
+  name: employee-deployment-v1
 spec:
   selector:
     matchLabels:
       app: employee
+      version: v1
   template:
     metadata:
       labels:
         app: employee
+        version: v1
     spec:
       containers:
       - name: employee
         image: piomin/employee-service
         ports:
         - containerPort: 8080
+        volumeMounts:
+          - mountPath: /etc/podinfo
+            name: podinfo
+      volumes:
+        - name: podinfo
+          downwardAPI:
+            items:
+              - path: "labels"
+                fieldRef:
+                  fieldPath: metadata.labels
+---
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: employee-deployment-v2
+spec:
+  selector:
+    matchLabels:
+      app: employee
+      version: v2
+  template:
+    metadata:
+      labels:
+        app: employee
+        version: v2
+    spec:
+      containers:
+        - name: employee
+          image: piomin/employee-service
+          ports:
+            - containerPort: 8080
+          volumeMounts:
+            - mountPath: /etc/podinfo
+              name: podinfo
+      volumes:
+        - name: podinfo
+          downwardAPI:
+            items:
+              - path: "labels"
+                fieldRef:
+                  fieldPath: metadata.labels
 ---
 apiVersion: v1
 kind: Service

simple-microservices/employee-service/k8s/istio.yaml

@@ -0,0 +1,42 @@
+apiVersion: networking.istio.io/v1beta1
+kind: DestinationRule
+metadata:
+  name: employee-service-destination
+spec:
+  host: employee-service.default.svc.cluster.local
+  subsets:
+    - name: v1
+      labels:
+        version: v1
+    - name: v2
+      labels:
+        version: v2
+---
+apiVersion: networking.istio.io/v1beta1
+kind: VirtualService
+metadata:
+  name: employee-service-route
+spec:
+  hosts:
+    - employee-service.default.svc.cluster.local
+  http:
+    - match:
+        - headers:
+            X-Version:
+              exact: v1
+      route:
+        - destination:
+            host: employee-service.default.svc.cluster.local
+            subset: v1
+    - match:
+        - headers:
+            X-Version:
+              exact: v2
+      route:
+        - destination:
+            host: employee-service.default.svc.cluster.local
+            subset: v2
+    - route:
+        - destination:
+            host: employee-service.default.svc.cluster.local
+            subset: v1

simple-microservices/employee-service/src/main/kotlin/pl/piomin/samples/kubernetes/employee/controller/EmployeeController.kt

@@ -1,28 +1,49 @@
 package pl.piomin.samples.kubernetes.employee.controller
 
+import org.slf4j.Logger
+import org.slf4j.LoggerFactory
 import org.springframework.web.bind.annotation.*
 import pl.piomin.samples.kubernetes.employee.domain.Employee
+import pl.piomin.samples.kubernetes.employee.domain.dto.AbstractEmployeeDTO
+import pl.piomin.samples.kubernetes.employee.domain.dto.EmployeeV1DTO
+import pl.piomin.samples.kubernetes.employee.domain.dto.EmployeeV2DTO
 import pl.piomin.samples.kubernetes.employee.repository.EmployeeRepository
+import pl.piomin.samples.kubernetes.employee.service.AppVersion
 import java.util.*
 
 @RestController
 @RequestMapping("/employees")
-class EmployeeController(val repository: EmployeeRepository) {
+class EmployeeController(val repository: EmployeeRepository,
+                         val appVersion: AppVersion) {
+
+    val logger: Logger = LoggerFactory.getLogger(EmployeeController::class.java)
 
     @PostMapping
     fun add(@RequestBody employee: Employee): Employee = repository.save(employee)
 
     @GetMapping("/{id}")
-    fun findById(@PathVariable id: Int): Optional<Employee> = repository.findById(id)
+    fun findById(@PathVariable id: Int): Optional<AbstractEmployeeDTO> = repository.findById(id)
+            .map { mapEmployee(it) }
 
     @GetMapping
-    fun findAll(): Iterable<Employee> = repository.findAll()
+    fun findAll(): Iterable<AbstractEmployeeDTO> = repository.findAll().map { mapEmployee(it) }
 
     @GetMapping("/organization/{organizationId}")
-    fun findByOrganizationId(@PathVariable organizationId: Int): Set<Employee> =
-            repository.findByOrganizationId(organizationId)
+    fun findByOrganizationId(@PathVariable organizationId: Int): List<AbstractEmployeeDTO> =
+            repository.findByOrganizationId(organizationId).map { mapEmployee(it) }
 
     @GetMapping("/department/{departmentId}")
-    fun findByDepartmentId(@PathVariable departmentId: Int): Set<Employee> =
-            repository.findByDepartmentId(departmentId)
+    fun findByDepartmentId(@PathVariable departmentId: Int): List<AbstractEmployeeDTO> =
+            repository.findByDepartmentId(departmentId).map { mapEmployee(it) }
+
+    fun mapEmployee(employee: Employee): AbstractEmployeeDTO {
+        logger.info("Version: {}", appVersion.getVersion())
+        return if (appVersion.getVersion()!!.contains("v1"))
+            EmployeeV1DTO(employee.id, employee.firstName, employee.lastName, employee.position,
+                    employee.organizationId, employee.departmentId)
+        else
+            EmployeeV2DTO(employee.id, "${employee.firstName} ${employee.lastName}", employee.position,
+                    employee.organizationId, employee.departmentId)
+    }
+
 }

simple-microservices/employee-service/src/main/kotlin/pl/piomin/samples/kubernetes/employee/domain/dto/AbstractEmployeeDTO.kt

@@ -0,0 +1,6 @@
+package pl.piomin.samples.kubernetes.employee.domain.dto
+
+abstract class AbstractEmployeeDTO(var id: Int? = null,
+                                   val position: String = "",
+                                   val organizationId: Int = 0,
+                                   val departmentId: Int = 0)

simple-microservices/employee-service/src/main/kotlin/pl/piomin/samples/kubernetes/employee/domain/dto/EmployeeV1DTO.kt

@@ -0,0 +1,9 @@
+package pl.piomin.samples.kubernetes.employee.domain.dto
+
+class EmployeeV1DTO(id: Int? = null,
+                    val firstName: String = "",
+                    val lastName: String = "",
+                    position: String = "",
+                    organizationId: Int = 0,
+                    departmentId: Int = 0):
+        AbstractEmployeeDTO(id, position, organizationId, departmentId)

simple-microservices/employee-service/src/main/kotlin/pl/piomin/samples/kubernetes/employee/domain/dto/EmployeeV2DTO.kt

@@ -0,0 +1,8 @@
+package pl.piomin.samples.kubernetes.employee.domain.dto
+
+class EmployeeV2DTO(id: Int? = null,
+                    val name: String = "",
+                    position: String = "",
+                    organizationId: Int = 0,
+                    departmentId: Int = 0):
+        AbstractEmployeeDTO(id, position, organizationId, departmentId)

simple-microservices/employee-service/src/main/kotlin/pl/piomin/samples/kubernetes/employee/service/AppVersion.kt

@@ -0,0 +1,16 @@
+package pl.piomin.samples.kubernetes.employee.service
+
+import org.springframework.stereotype.Service
+import java.io.File
+
+@Service
+class AppVersion {
+
+    fun getVersion(): String? {
+        val file = File("/etc/podinfo/labels")
+        return if(file.exists()) {
+            file.readLines().first{ it.startsWith("version=")}
+                    .split("=")[1]
+        } else null
+    }
+}