feat: propagate proxy variables to jobs, services and builds (#1112)

Set `http_proxy`, `https_proxy` and `no_proxy` in the runner's environment and everything the runner controls uses them.

Go already read them for the runner's own requests. This adds jobs, in lower and upper case, service containers, and Dockerfile action builds.

Some hosts are added to `no_proxy` for jobs so they stay direct: the cache server, loopback, the job's service containers, and a `tcp://` Docker daemon. Without the last one the Docker client sends its API calls to the proxy and docker-in-docker breaks. Gitea is not added.

Images are pulled by the Docker daemon, which has its own proxy setting. In the `dind` images it reads these same variables. The runner warns at startup if it has a proxy and the daemon does not.

Fixes https://gitea.com/gitea/runner/issues/1118, originally reported as https://gitea.com/gitea/runner/issues/708.

---------

Co-authored-by: silverwind <2021+silverwind@noreply.gitea.com>
Co-authored-by: silverwind <me@silverwind.io>
Reviewed-on: https://gitea.com/gitea/runner/pulls/1112
Reviewed-by: silverwind <2021+silverwind@noreply.gitea.com>
Co-authored-by: bircni <bircni@icloud.com>

act/container/container_types.go

@@ -82,6 +82,7 @@ type NewDockerBuildExecutorInput struct {
 	BuildContext io.Reader
 	ImageTag     string
 	Platform     string
+	BuildArgs    map[string]*string
 }
 
 // NewDockerNetworkCreateExecutorInput the input for the NewDockerNetworkCreateExecutor function

act/container/docker_build.go

@@ -49,6 +49,7 @@ func NewDockerBuildExecutor(input NewDockerBuildExecutorInput) common.Executor {
 			Remove:      true,
 			AuthConfigs: LoadDockerAuthConfigs(ctx),
 			Dockerfile:  input.Dockerfile,
+			BuildArgs:   input.BuildArgs,
 		}
 		platform, err := parsePlatform(input.Platform)
 		if err != nil {

act/runner/action.go

@@ -372,6 +372,7 @@ func execAsDocker(ctx context.Context, step actionStep, actionName, actionDir, b
 				ImageTag:     image,
 				BuildContext: buildContext,
 				Platform:     rc.Config.ContainerArchitecture,
+				BuildArgs:    rc.proxyBuildArgs(),
 			})
 			if buildContext == nil {
 				// Held across the whole build: the daemon drains contextDir lazily.

act/runner/run_context.go

@@ -435,7 +435,9 @@ func (rc *RunContext) startJobContainer() common.Executor {
 				continue
 			}
 			// interpolate env
-			interpolatedEnvs := make(map[string]string, len(spec.Env))
+			interpolatedEnvs := make(map[string]string, len(spec.Env)+len(rc.Config.ProxyEnv))
+			// a service reaches the internet the way the job does; its own env still wins
+			maps0.Copy(interpolatedEnvs, rc.Config.ProxyEnv)
 			for k, v := range spec.Env {
 				interpolatedEnvs[k] = rc.ExprEval.Interpolate(ctx, v)
 			}
@@ -969,6 +971,20 @@ func (rc *RunContext) isEnabled(ctx context.Context) (bool, error) {
 	return true, nil
 }
 
+// proxyBuildArgs returns the job's proxy variables as docker build args. The docker CLI
+// pre-populates these from its own client configuration, but act builds through the API,
+// so without them a Dockerfile action's RUN steps have no network behind a proxy.
+func (rc *RunContext) proxyBuildArgs() map[string]*string {
+	if len(rc.Config.ProxyEnv) == 0 {
+		return nil
+	}
+	args := make(map[string]*string, len(rc.Config.ProxyEnv))
+	for name, value := range rc.Config.ProxyEnv {
+		args[name] = &value
+	}
+	return args
+}
+
 func mergeMaps(maps ...map[string]string) map[string]string {
 	rtnMap := make(map[string]string)
 	for _, m := range maps {

act/runner/run_context_test.go

@@ -292,6 +292,83 @@ jobs:
 	require.Equal(t, [2]string{"", ""}, credentials["redis:latest"])
 }
 
+// A service container reaches the internet the same way the job does, so it inherits the
+// job's proxy; a service that sets the variable itself keeps its own value.
+func TestStartJobContainerGivesServicesTheJobProxy(t *testing.T) {
+	workflow, err := model.ReadWorkflow(strings.NewReader(`
+name: test
+on: push
+jobs:
+  job:
+    runs-on: ubuntu-latest
+    container:
+      image: registry.example/job:latest
+    services:
+      redis:
+        image: redis:latest
+      db:
+        image: postgres:latest
+        env:
+          no_proxy: db-only.example
+    steps: []
+`))
+	require.NoError(t, err)
+
+	var inputs []*container.NewContainerInput
+	origNewContainer := newContainer
+	newContainer = func(input *container.NewContainerInput) container.ExecutionsEnvironment {
+		inputs = append(inputs, input)
+		return fakeContainer{}
+	}
+	t.Cleanup(func() { newContainer = origNewContainer })
+
+	rc := &RunContext{
+		Name: "test",
+		Config: &Config{
+			Workdir:              "/tmp",
+			ContainerNetworkMode: "host",
+			ReuseContainers:      true,
+			Env:                  map[string]string{},
+			ProxyEnv:             map[string]string{"http_proxy": "http://proxy:3128", "no_proxy": "internal.example"},
+			Secrets:              map[string]string{},
+		},
+		Env: map[string]string{},
+		Run: &model.Run{
+			JobID:    "job",
+			Workflow: workflow,
+		},
+	}
+	rc.ExprEval = rc.NewExpressionEvaluator(t.Context())
+
+	require.NoError(t, rc.startJobContainer()(t.Context()))
+
+	env := map[string][]string{}
+	for _, in := range inputs {
+		env[in.Image] = in.Env
+	}
+
+	require.Contains(t, env["redis:latest"], "http_proxy=http://proxy:3128")
+	require.Contains(t, env["redis:latest"], "no_proxy=internal.example")
+	// the service's own env wins over what the runner injected, without dropping the rest
+	require.Contains(t, env["postgres:latest"], "no_proxy=db-only.example")
+	require.NotContains(t, env["postgres:latest"], "no_proxy=internal.example")
+	require.Contains(t, env["postgres:latest"], "http_proxy=http://proxy:3128")
+}
+
+// act builds Dockerfile actions through the API, which does not pre-populate the proxy
+// build args the docker CLI would, so the RUN steps would have no network behind a proxy.
+func TestProxyBuildArgs(t *testing.T) {
+	rc := &RunContext{Config: &Config{ProxyEnv: map[string]string{"http_proxy": "http://proxy:3128"}}}
+
+	args := rc.proxyBuildArgs()
+
+	require.Len(t, args, 1)
+	require.Equal(t, "http://proxy:3128", *args["http_proxy"])
+
+	// a job without a proxy builds exactly as it does today
+	require.Nil(t, (&RunContext{Config: &Config{}}).proxyBuildArgs())
+}
+
 func TestRunContext_GetBindsAndMounts(t *testing.T) {
 	rctemplate := &RunContext{
 		Name: "TestRCName",

act/runner/runner.go

@@ -73,6 +73,7 @@ type Config struct {
 	ContainerNetworkMode               docker_container.NetworkMode                  // the network mode of job containers (the value of --network)
 	ContainerNetworkCreateOptions      container.NewDockerNetworkCreateExecutorInput // the default network create options
 	ActionCache                        ActionCache                                   // Use a custom ActionCache Implementation
+	ProxyEnv                           map[string]string                             // the proxy variables the job runs with, also given to service containers and image builds
 
 	PresetGitHubContext   *model.GithubContext // the preset github context, overrides some fields like DefaultBranch, Env, Secrets etc.
 	EventJSON             string               // the content of JSON file to use for event.json in containers, overrides EventPath