docker: extra_hosts argument to add hosts to a container’s /etc/hosts…

internal/build/options.go

@@ -24,6 +24,7 @@ func Options(archive io.Reader, spec v1alpha1.DockerImageSpec) docker.BuildOptio
  CacheFrom: spec.CacheFrom,
  PullParent: spec.Pull,
  Platform: spec.Platform,
+ ExtraHosts: spec.ExtraHosts,
  }
 }
 

internal/docker/client.go

@@ -543,6 +543,7 @@ func (c *Cli) ImageBuild(ctx context.Context, g *errgroup.Group, buildContext io
  opts.CacheFrom = options.CacheFrom
  opts.PullParent = options.PullParent
  opts.Platform = options.Platform
+ opts.ExtraHosts = append([]string{}, options.ExtraHosts...)
 
  if options.DirSource != nil {
  opts.RemoteContext = clientSessionRemote

internal/docker/options.go

@@ -21,4 +21,5 @@ type BuildOptions struct {
  ExtraTags []string
  ForceLegacyBuilder bool
  DirSource filesync.DirSource
+ ExtraHosts []string
 }

internal/tiltfile/docker.go

@@ -79,6 +79,8 @@ type dockerImage struct {
 
  dockerComposeService string
  dockerComposeLocalVolumePaths []string
+
+ extraHosts []string
 }
 
 func (d *dockerImage) ID() model.TargetID {
@@ -114,7 +116,7 @@ func (s *tiltfileState) dockerBuild(thread *starlark.Thread, fn *starlark.Builti
  entrypoint starlark.Value
  var buildArgs value.StringStringMap
  var network, platform value.Stringable
- var ssh, secret, extraTags, cacheFrom value.StringOrStringList
+ var ssh, secret, extraTags, cacheFrom, extraHosts value.StringOrStringList
  var matchInEnvVars, pullParent bool
  var overrideArgsVal starlark.Sequence
  if err := s.unpackArgs(fn.Name(), args, kwargs,
@@ -138,6 +140,7 @@ func (s *tiltfileState) dockerBuild(thread *starlark.Thread, fn *starlark.Builti
  "cache_from?", &cacheFrom,
  "pull?", &pullParent,
  "platform?", &platform,
+ "extra_hosts?", &extraHosts,
  ); err != nil {
  return nil, err
  }
@@ -256,6 +259,7 @@ func (s *tiltfileState) dockerBuild(thread *starlark.Thread, fn *starlark.Builti
  pullParent: pullParent,
  platform: platform.Value,
  tiltfilePath: starkit.CurrentExecPath(thread),
+ extraHosts: extraHosts.Values,
  }
  err = s.buildIndex.addImage(r)
  if err != nil {

internal/tiltfile/docker_test.go

@@ -3,6 +3,7 @@ package tiltfile
 import (
  "fmt"
  "path/filepath"
+ "strings"
  "testing"
 
  "github.com/stretchr/testify/assert"
@@ -204,3 +205,55 @@ custom_build('gcr.io/fe', 'export MY_REF="gcr.io/fe:dev" && docker build -t $MY_
 
  f.loadErrString("Cannot specify both tag= and outputs_image_ref_to=")
 }
+
+func TestExtraHosts(t *testing.T) {
+ type tc struct {
+ name string
+ argValue []string
+ expected []string
+ }
+ tcs := []tc{
+ {
+ //docker_build('gcr.io/fe', '.')
+ name: "No Extra Hosts",
+ },
+ {
+ // docker_build('gcr.io/fe', '.', extra_hosts='testing.example.com:10.0.0.1')
+ name: "One Extra Host Only",
+ argValue: []string{"testing.example.com:10.0.0.1"},
+ expected: []string{"testing.example.com:10.0.0.1"},
+ },
+ {
+ // docker_build('gcr.io/fe', '.', extra_hosts=["testing.example.com:10.0.0.1","app.testing.example.com:10.0.0.3"])
+ name: "Two Extra Hosts",
+ argValue: []string{"testing.example.com:10.0.0.1", "app.testing.example.com:10.0.0.3"},
+ expected: []string{"testing.example.com:10.0.0.1", "app.testing.example.com:10.0.0.3"},
+ },
+ }
+
+ for _, tt := range tcs {
+ t.Run(
+ tt.name, func(t *testing.T) {
+ f := newFixture(t)
+
+ f.yaml("fe.yaml", deployment("fe", image("gcr.io/fe")))
+ f.file("Dockerfile", `FROM alpine`)
+
+ tf := "k8s_yaml('fe.yaml')\ndocker_build('gcr.io/fe', '.'"
+ if len(tt.argValue) == 1 {
+ tf += fmt.Sprintf(", extra_hosts='%s'", tt.argValue[0])
+ } else if len(tt.argValue) > 1 {
+ tf += `, extra_hosts=["` + strings.Join(tt.argValue, `","`) + `"]`
+ }
+ tf += ")"
+ fmt.Println(tf)
+
+ f.file("Tiltfile", tf)
+
+ f.load()
+ m := f.assertNextManifest("fe")
+ require.Equal(t, tt.expected, m.ImageTargetAt(0).DockerBuildInfo().ExtraHosts)
+ },
+ )
+ }
+}

internal/tiltfile/tiltfile_state.go

@@ -1456,6 +1456,7 @@ func (s *tiltfileState) imgTargetsForDepsHelper(mn model.ManifestName, imageMapD
  Platform: image.platform,
  ExtraTags: image.extraTags,
  ContextIgnores: contextIgnores,
+ ExtraHosts: image.extraHosts,
  }
  iTarget = iTarget.WithBuildDetails(model.DockerBuild{DockerImageSpec: spec})
  case CustomBuild:

pkg/apis/core/v1alpha1/dockerimage_types.go

@@ -174,6 +174,13 @@ type DockerImageSpec struct {
  //
  // +optional
  ClusterNeeds ClusterImageNeeds `json:"clusterNeeds,omitempty" protobuf:"bytes,15,opt,name=clusterNeeds,casttype=ClusterImageNeeds"`
+
+ // Other hosts to be added into a container’s /etc/hosts file
+ //
+ // https://docs.docker.com/engine/reference/commandline/build/#add-host
+ //
+ // Equivalent to `--add-host` in the Docker CLI.
+ ExtraHosts []string `json:"extraHosts,omitempty" protobuf:"bytes,17,opt,name=extraHosts"`
 }
 
 var _ resource.Object = &DockerImage{}