hook up global networks

.drone.yml

@@ -78,6 +78,16 @@ steps:
     - refs/heads/master
     - refs/tags/*
 
+volumes:
+- name: go
+  temp: {}
+
+---
+kind: pipeline
+type: docker
+name: manifest
+
+steps:
 - name: manifest
   image: plugins/manifest
   settings:
@@ -88,11 +98,11 @@ steps:
       from_secret: docker_password
     username:
       from_secret: docker_username
-  when:
-    ref:
-    - refs/heads/master
-    - refs/tags/*
 
-volumes:
+depends_on:
-- name: go
+- linux
-  temp: {}
+
+trigger:
+  ref:
+  - refs/heads/master
+  - refs/tags/*

engine/compiler/util.go

@@ -63,6 +63,9 @@ func configureSerial(spec *engine.Spec) {
 func convertStaticEnv(src map[string]*manifest.Variable) map[string]string {
 	dst := map[string]string{}
 	for k, v := range src {
+		if v == nil {
+			continue
+		}
 		if strings.TrimSpace(v.Secret) == "" {
 			dst[k] = v.Value
 		}
@@ -76,6 +79,9 @@ func convertStaticEnv(src map[string]*manifest.Variable) map[string]string {
 func convertSecretEnv(src map[string]*manifest.Variable) []*engine.Secret {
 	dst := []*engine.Secret{}
 	for k, v := range src {
+		if v == nil {
+			continue
+		}
 		if strings.TrimSpace(v.Secret) != "" {
 			dst = append(dst, &engine.Secret{
 				Name: v.Secret,

engine/convert.go

@@ -251,7 +251,9 @@ func toVolumeType(from *Volume) mount.Type {
 func toEnv(env map[string]string) []string {
 	var envs []string
 	for k, v := range env {
-		envs = append(envs, k+"="+v)
+		if v != "" {
+			envs = append(envs, k+"="+v)
+		}
 	}
 	return envs
 }

engine/engine_impl.go

@@ -16,6 +16,7 @@ import (
 
 	"docker.io/go-docker"
 	"docker.io/go-docker/api/types"
+	"docker.io/go-docker/api/types/network"
 	"docker.io/go-docker/api/types/volume"
 )
 
@@ -214,6 +215,19 @@ func (e *Docker) create(ctx context.Context, spec *Spec, step *Step, output io.W
 		return err
 	}
 
+	// attach the container to user-defined networks.
+	// primarily used to attach global user-defined networks.
+	if step.Network == "" {
+		for _, net := range step.Networks {
+			err = e.client.NetworkConnect(ctx, net, step.ID, &network.EndpointSettings{
+				Aliases: []string{net},
+			})
+			if err != nil {
+				return nil
+			}
+		}
+	}
+
 	return nil
 }