Add support for env in podtemplate

docs/podtemplates.md

@@ -49,6 +49,10 @@ Pod templates support fields listed in the table below.
 			<td><code>volumes</code></td>
 			<td>Specifies a list of volumes that containers within the Pod can mount. This allows you to specify a volume type for each <code>volumeMount</code> in a <code>Task</code>.</td>
 		</tr>
+        <tr>
+			<td><code>env</code></td>
+			<td>Specifies a list of environments that all containers within the Pod will be populated</td>
+		</tr>
 		<tr>
 			<td><code>runtimeClassName</code></td>
 			<td>Specifies the <a href=https://kubernetes.io/docs/concepts/containers/runtime-class/>runtime class</a> for the Pod.</td>

examples/v1beta1/taskruns/podtemplate-env.yaml

@@ -0,0 +1,15 @@
+apiVersion: tekton.dev/v1beta1
+kind: TaskRun
+metadata:
+  generateName: podtemplate-env-
+spec:
+  podTemplate:
+    env:
+      - name: MY_VAR1
+        value: foo
+  taskSpec:
+    steps:
+      - image: ubuntu
+        script: |
+          #!/usr/bin/env bash
+          [[ $MY_VAR1 == foo ]]

pkg/apis/pipeline/pod/template.go

@@ -52,6 +52,12 @@ type Template struct {
 	// +patchStrategy=merge,retainKeys
 	Volumes []corev1.Volume `json:"volumes,omitempty" patchStrategy:"merge,retainKeys" patchMergeKey:"name" protobuf:"bytes,1,rep,name=volumes"`
 
+	// List of environment variables that can be provided to the containers belonging to the pod.
+	// +optional
+	// +patchMergeKey=name
+	// +patchStrategy=merge,retainKeys
+	Env []corev1.EnvVar `json:"env,omitempty" patchStrategy:"merge,retainKeys" patchMergeKey:"name" protobuf:"bytes,1,rep,name=env"`
+
 	// RuntimeClassName refers to a RuntimeClass object in the node.k8s.io
 	// group, which should be used to run this pod. If no RuntimeClass resource
 	// matches the named class, the pod will not be run. If unset or empty, the

pkg/apis/pipeline/v1beta1/swagger.json

@@ -31,6 +31,15 @@
           "description": "EnableServiceLinks indicates whether information about services should be injected into pod's environment variables, matching the syntax of Docker links. Optional: Defaults to true.",
           "type": "boolean"
         },
+        "env": {
+          "description": "List of environment variables that can be provided to the containers belonging to the pod.",
+          "type": "array",
+          "items": {
+            "$ref": "#/definitions/v1.EnvVar"
+          },
+          "x-kubernetes-patch-merge-key": "name",
+          "x-kubernetes-patch-strategy": "merge,retainKeys"
+        },
         "hostNetwork": {
           "description": "HostNetwork specifies whether the pod may use the node network namespace",
           "type": "boolean"

pkg/pod/pod.go

@@ -217,6 +217,30 @@ func (b *Builder) Build(ctx context.Context, taskRun *v1beta1.TaskRun, taskSpec
 		podTemplate = *taskRun.Spec.PodTemplate
 	}
 
+	// Add envs specified in podtemplate to all step containers
+	// Envs specified in podtemplate should take precedence over
+	// the one specified in step and step template
+	for i := range stepContainers {
+		envs := updateAndMergeEnv(stepContainers[i].Env, podTemplate.Env)
+		stepContainers[i].Env = envs
+	}
+
+	// Add envs specified in podtemplate to all sidecar containers
+	// Envs specified in podtemplate should take precedence over
+	// the one specified in sidecar and step template
+	for i := range sidecarContainers {
+		envs := updateAndMergeEnv(sidecarContainers[i].Env, podTemplate.Env)
+		sidecarContainers[i].Env = envs
+	}
+
+	// Add envs specified in podtemplate to all initContainers
+	// Envs specified in podtemplate should take precedence over
+	// the one specified in init and step template
+	for i := range initContainers {
+		envs := updateAndMergeEnv(initContainers[i].Env, podTemplate.Env)
+		initContainers[i].Env = envs
+	}
+
 	// Add podTemplate Volumes to the explicitly declared use volumes
 	volumes = append(volumes, taskSpec.Volumes...)
 	volumes = append(volumes, podTemplate.Volumes...)
@@ -403,3 +427,22 @@ func shouldAddReadyAnnotationOnPodCreate(ctx context.Context, sidecars []v1beta1
 	cfg := config.FromContextOrDefaults(ctx)
 	return !cfg.FeatureFlags.RunningInEnvWithInjectedSidecars
 }
+
+// updateAndMergeEnv will merge two slices of env
+// precedence will be given to second input if exist with same name key
+func updateAndMergeEnv(containerenvs []corev1.EnvVar, podtemplateEnvs []corev1.EnvVar) []corev1.EnvVar {
+	for _, env := range podtemplateEnvs {
+		var updated bool
+		for i := range containerenvs {
+			if env.Name == containerenvs[i].Name {
+				containerenvs[i].Value = env.Value
+				containerenvs[i].ValueFrom = env.ValueFrom
+				updated = true
+			}
+		}
+		if !updated {
+			containerenvs = append(containerenvs, env)
+		}
+	}
+	return containerenvs
+}