From 1f48684ca7849699cd06ff557e8018bbd34eef29 Mon Sep 17 00:00:00 2001
From: twsl <45483159+twsl@users.noreply.github.com>
Date: Mon, 31 Mar 2025 17:22:35 +0200
Subject: [PATCH 1/8] Update devcontainer_test.go
---
devcontainer/devcontainer_test.go | 3 +++
1 file changed, 3 insertions(+)
diff --git a/devcontainer/devcontainer_test.go b/devcontainer/devcontainer_test.go
index d304e76..5ebd0bf 100644
--- a/devcontainer/devcontainer_test.go
+++ b/devcontainer/devcontainer_test.go
@@ -204,6 +204,9 @@ func TestImageFromDockerfile(t *testing.T) {
}, {
content: "ARG VARIANT=\"3.10\"\nFROM mcr.microsoft.com/devcontainers/python:0-${VARIANT}",
image: "mcr.microsoft.com/devcontainers/python:0-3.10",
+ }, {
+ content: "ARG VARIANT=3-bookworm\nFROM mcr.microsoft.com/devcontainers/python:1-${VARIANT}",
+ image: "mcr.microsoft.com/devcontainers/python:1-3-bookworm",
}, {
content: "ARG VARIANT=\"3.10\"\nFROM mcr.microsoft.com/devcontainers/python:0-$VARIANT ",
image: "mcr.microsoft.com/devcontainers/python:0-3.10",
From b8b3dcc7c9d04d92ed209110cbc8d466f21c5c26 Mon Sep 17 00:00:00 2001
From: twsl <45483159+twsl@users.noreply.github.com>
Date: Mon, 31 Mar 2025 17:41:07 +0200
Subject: [PATCH 2/8] Update devcontainer_test.go
---
devcontainer/devcontainer_test.go | 35 +++++++++++++++++++++++++++++++
1 file changed, 35 insertions(+)
diff --git a/devcontainer/devcontainer_test.go b/devcontainer/devcontainer_test.go
index 5ebd0bf..dab7d35 100644
--- a/devcontainer/devcontainer_test.go
+++ b/devcontainer/devcontainer_test.go
@@ -221,6 +221,41 @@ func TestImageFromDockerfile(t *testing.T) {
}
}
+func TestImageFromDockerfileWithArgs(t *testing.T) {
+ t.Parallel()
+ dc := &devcontainer.Spec{
+ Build: devcontainer.BuildSpec{
+ Dockerfile: "Dockerfile",
+ Context: ".",
+ Args: map[string]string{
+ "VARIANT": "3.11-bookworm",
+ },
+ },
+ }
+ fs := memfs.New()
+ params, err := dc.Compile(fs, "", workingDir, "", "", false, stubLookupEnv)
+ require.Equal(t, "VARIANT=3.11-bookworm", params.BuildArgs[0])
+
+ for _, tc := range []struct {
+ content string
+ image string
+ }{{
+ content: "ARG VARIANT=3-bookworm\nFROM mcr.microsoft.com/devcontainers/python:1-${VARIANT}",
+ image: "mcr.microsoft.com/devcontainers/python:1-3.11-bookworm",
+ }, {
+ content: "ARG VARIANT=\"3.10\"\nFROM mcr.microsoft.com/devcontainers/python:1-$VARIANT ",
+ image: "mcr.microsoft.com/devcontainers/python:1-3.11-bookworm",
+ }} {
+ tc := tc
+ t.Run(tc.image, func(t *testing.T) {
+ t.Parallel()
+ ref, err := devcontainer.ImageFromDockerfile(tc.content)
+ require.NoError(t, err)
+ require.Equal(t, tc.image, ref.Name())
+ })
+ }
+}
+
func TestUserFrom(t *testing.T) {
t.Parallel()
From 1fa47ec9b86b5a91509be37c86531c4cd75d16be Mon Sep 17 00:00:00 2001
From: twsl <45483159+twsl@users.noreply.github.com>
Date: Mon, 31 Mar 2025 17:52:31 +0200
Subject: [PATCH 3/8] Update devcontainer_test.go
---
devcontainer/devcontainer_test.go | 18 +++++++++++++++---
1 file changed, 15 insertions(+), 3 deletions(-)
diff --git a/devcontainer/devcontainer_test.go b/devcontainer/devcontainer_test.go
index dab7d35..a43fb05 100644
--- a/devcontainer/devcontainer_test.go
+++ b/devcontainer/devcontainer_test.go
@@ -232,9 +232,6 @@ func TestImageFromDockerfileWithArgs(t *testing.T) {
},
},
}
- fs := memfs.New()
- params, err := dc.Compile(fs, "", workingDir, "", "", false, stubLookupEnv)
- require.Equal(t, "VARIANT=3.11-bookworm", params.BuildArgs[0])
for _, tc := range []struct {
content string
@@ -249,6 +246,21 @@ func TestImageFromDockerfileWithArgs(t *testing.T) {
tc := tc
t.Run(tc.image, func(t *testing.T) {
t.Parallel()
+
+ fs := memfs.New()
+ dcDir := "/workspaces/coder/.devcontainer"
+ err := fs.MkdirAll(dcDir, 0o755)
+ require.NoError(t, err)
+ file, err := fs.OpenFile(filepath.Join(dcDir, "Dockerfile"), os.O_CREATE|os.O_WRONLY, 0o644)
+ require.NoError(t, err)
+ _, err = io.WriteString(file, tc.content)
+ require.NoError(t, err)
+ _ = file.Close()
+ params, err := dc.Compile(fs, dcDir, workingDir, "", "/var/workspace", false, stubLookupEnv)
+
+ require.Equal(t, "VARIANT=3.11-bookworm", params.BuildArgs[0])
+ require.Equal(t, params.DockerfileContent, tc.content)
+
ref, err := devcontainer.ImageFromDockerfile(tc.content)
require.NoError(t, err)
require.Equal(t, tc.image, ref.Name())
From 3d03c86751ee82125b28c8a08014814fe99f456e Mon Sep 17 00:00:00 2001
From: twsl <45483159+twsl@users.noreply.github.com>
Date: Mon, 31 Mar 2025 18:01:24 +0200
Subject: [PATCH 4/8] Update devcontainer_test.go
---
devcontainer/devcontainer_test.go | 24 ++++++++++--------------
1 file changed, 10 insertions(+), 14 deletions(-)
diff --git a/devcontainer/devcontainer_test.go b/devcontainer/devcontainer_test.go
index a43fb05..d0cf973 100644
--- a/devcontainer/devcontainer_test.go
+++ b/devcontainer/devcontainer_test.go
@@ -222,17 +222,7 @@ func TestImageFromDockerfile(t *testing.T) {
}
func TestImageFromDockerfileWithArgs(t *testing.T) {
- t.Parallel()
- dc := &devcontainer.Spec{
- Build: devcontainer.BuildSpec{
- Dockerfile: "Dockerfile",
- Context: ".",
- Args: map[string]string{
- "VARIANT": "3.11-bookworm",
- },
- },
- }
-
+ t.Parallel()
for _, tc := range []struct {
content string
image string
@@ -246,7 +236,15 @@ func TestImageFromDockerfileWithArgs(t *testing.T) {
tc := tc
t.Run(tc.image, func(t *testing.T) {
t.Parallel()
-
+ dc := &devcontainer.Spec{
+ Build: devcontainer.BuildSpec{
+ Dockerfile: "Dockerfile",
+ Context: ".",
+ Args: map[string]string{
+ "VARIANT": "3.11-bookworm",
+ },
+ },
+ }
fs := memfs.New()
dcDir := "/workspaces/coder/.devcontainer"
err := fs.MkdirAll(dcDir, 0o755)
@@ -257,10 +255,8 @@ func TestImageFromDockerfileWithArgs(t *testing.T) {
require.NoError(t, err)
_ = file.Close()
params, err := dc.Compile(fs, dcDir, workingDir, "", "/var/workspace", false, stubLookupEnv)
-
require.Equal(t, "VARIANT=3.11-bookworm", params.BuildArgs[0])
require.Equal(t, params.DockerfileContent, tc.content)
-
ref, err := devcontainer.ImageFromDockerfile(tc.content)
require.NoError(t, err)
require.Equal(t, tc.image, ref.Name())
From e503d3feca8f9574892cdf8bbaaf359085d139d6 Mon Sep 17 00:00:00 2001
From: twsl <45483159+twsl@users.noreply.github.com>
Date: Mon, 31 Mar 2025 18:08:49 +0200
Subject: [PATCH 5/8] Update devcontainer_test.go
---
devcontainer/devcontainer_test.go | 1 +
1 file changed, 1 insertion(+)
diff --git a/devcontainer/devcontainer_test.go b/devcontainer/devcontainer_test.go
index d0cf973..949e541 100644
--- a/devcontainer/devcontainer_test.go
+++ b/devcontainer/devcontainer_test.go
@@ -255,6 +255,7 @@ func TestImageFromDockerfileWithArgs(t *testing.T) {
require.NoError(t, err)
_ = file.Close()
params, err := dc.Compile(fs, dcDir, workingDir, "", "/var/workspace", false, stubLookupEnv)
+ require.NoError(t, err)
require.Equal(t, "VARIANT=3.11-bookworm", params.BuildArgs[0])
require.Equal(t, params.DockerfileContent, tc.content)
ref, err := devcontainer.ImageFromDockerfile(tc.content)
From f60fff8784c6c383c6ee6f7909993e3d6e25288a Mon Sep 17 00:00:00 2001
From: twsl <45483159+twsl@users.noreply.github.com>
Date: Mon, 31 Mar 2025 18:10:48 +0200
Subject: [PATCH 6/8] Update devcontainer_test.go
---
devcontainer/devcontainer_test.go | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/devcontainer/devcontainer_test.go b/devcontainer/devcontainer_test.go
index 949e541..9582c99 100644
--- a/devcontainer/devcontainer_test.go
+++ b/devcontainer/devcontainer_test.go
@@ -222,7 +222,7 @@ func TestImageFromDockerfile(t *testing.T) {
}
func TestImageFromDockerfileWithArgs(t *testing.T) {
- t.Parallel()
+ t.Parallel()
for _, tc := range []struct {
content string
image string
From 5784366c3f7bec3a5a8f23017a3e0e1715afa748 Mon Sep 17 00:00:00 2001
From: twsl <45483159+twsl@users.noreply.github.com>
Date: Sat, 24 May 2025 21:35:03 +0000
Subject: [PATCH 7/8] Attempt to fix arg parsing
---
devcontainer/devcontainer.go | 102 ++++++++++++++++++++++++++----
devcontainer/devcontainer_test.go | 77 +++++++++++++++++++++-
envbuilder.go | 2 +-
3 files changed, 163 insertions(+), 18 deletions(-)
diff --git a/devcontainer/devcontainer.go b/devcontainer/devcontainer.go
index 0bf7cc3..c57e490 100644
--- a/devcontainer/devcontainer.go
+++ b/devcontainer/devcontainer.go
@@ -204,7 +204,7 @@ func (s *Spec) Compile(fs billy.Filesystem, devcontainerDir, scratchDir string,
// We should make a best-effort attempt to find the user.
// Features must be executed as root, so we need to swap back
// to the running user afterwards.
- params.User, err = UserFromDockerfile(params.DockerfileContent)
+ params.User, err = UserFromDockerfile(params.DockerfileContent, buildArgs)
if err != nil {
return nil, fmt.Errorf("user from dockerfile: %w", err)
}
@@ -308,12 +308,57 @@ func (s *Spec) compileFeatures(fs billy.Filesystem, devcontainerDir, scratchDir
// UserFromDockerfile inspects the contents of a provided Dockerfile
// and returns the user that will be used to run the container.
-func UserFromDockerfile(dockerfileContent string) (user string, err error) {
+// Optionally accepts build args that may override default values in the Dockerfile.
+func UserFromDockerfile(dockerfileContent string, buildArgs ...[]string) (user string, err error) {
+ var args []string
+ if len(buildArgs) > 0 {
+ args = buildArgs[0]
+ }
+
res, err := parser.Parse(strings.NewReader(dockerfileContent))
if err != nil {
return "", fmt.Errorf("parse dockerfile: %w", err)
}
+ // Parse build args and ARG instructions to build the substitution context
+ lexer := shell.NewLex('\\')
+
+ // Start with build args provided externally (e.g., from devcontainer.json)
+ argsCopy := make([]string, len(args))
+ copy(argsCopy, args)
+
+ // Parse build args into a map for easy lookup
+ buildArgsMap := make(map[string]string)
+ for _, arg := range args {
+ if parts := strings.SplitN(arg, "=", 2); len(parts) == 2 {
+ buildArgsMap[parts[0]] = parts[1]
+ }
+ }
+
+ // Process ARG instructions to add default values if not overridden
+ lines := strings.Split(dockerfileContent, "\n")
+ for _, line := range lines {
+ if arg, ok := strings.CutPrefix(line, "ARG "); ok {
+ arg = strings.TrimSpace(arg)
+ if strings.Contains(arg, "=") {
+ parts := strings.SplitN(arg, "=", 2)
+ key, _, err := lexer.ProcessWord(parts[0], shell.EnvsFromSlice(argsCopy))
+ if err != nil {
+ return "", fmt.Errorf("processing %q: %w", line, err)
+ }
+
+ // Only use the default value if no build arg was provided
+ if _, exists := buildArgsMap[key]; !exists {
+ val, _, err := lexer.ProcessWord(parts[1], shell.EnvsFromSlice(argsCopy))
+ if err != nil {
+ return "", fmt.Errorf("processing %q: %w", line, err)
+ }
+ argsCopy = append(argsCopy, key+"="+val)
+ }
+ }
+ }
+ }
+
// Parse stages and user commands to determine the relevant user
// from the final stage.
var (
@@ -371,10 +416,16 @@ func UserFromDockerfile(dockerfileContent string) (user string, err error) {
}
// If we can't find a user command, try to find the user from
- // the image.
- ref, err := name.ParseReference(strings.TrimSpace(stage.BaseName))
+ // the image. First, substitute any ARG variables in the image name.
+ imageRef := stage.BaseName
+ imageRef, _, err := lexer.ProcessWord(imageRef, shell.EnvsFromSlice(argsCopy))
if err != nil {
- return "", fmt.Errorf("parse image ref %q: %w", stage.BaseName, err)
+ return "", fmt.Errorf("processing image ref %q: %w", stage.BaseName, err)
+ }
+
+ ref, err := name.ParseReference(strings.TrimSpace(imageRef))
+ if err != nil {
+ return "", fmt.Errorf("parse image ref %q: %w", imageRef, err)
}
user, err := UserFromImage(ref)
if err != nil {
@@ -388,27 +439,50 @@ func UserFromDockerfile(dockerfileContent string) (user string, err error) {
// ImageFromDockerfile inspects the contents of a provided Dockerfile
// and returns the image that will be used to run the container.
-func ImageFromDockerfile(dockerfileContent string) (name.Reference, error) {
- lexer := shell.NewLex('\\')
+// Optionally accepts build args that may override default values in the Dockerfile.
+func ImageFromDockerfile(dockerfileContent string, buildArgs ...[]string) (name.Reference, error) {
var args []string
+ if len(buildArgs) > 0 {
+ args = buildArgs[0]
+ }
+
+ lexer := shell.NewLex('\\')
+
+ // Start with build args provided externally (e.g., from devcontainer.json)
+ // These have higher precedence than default values in ARG instructions
+ argsCopy := make([]string, len(args))
+ copy(argsCopy, args)
+
+ // Parse build args into a map for easy lookup
+ buildArgsMap := make(map[string]string)
+ for _, arg := range args {
+ if parts := strings.SplitN(arg, "=", 2); len(parts) == 2 {
+ buildArgsMap[parts[0]] = parts[1]
+ }
+ }
+
var imageRef string
lines := strings.Split(dockerfileContent, "\n")
- // Iterate over lines in reverse
+ // Iterate over lines in reverse to find ARG declarations and FROM instruction
for i := len(lines) - 1; i >= 0; i-- {
line := lines[i]
if arg, ok := strings.CutPrefix(line, "ARG "); ok {
arg = strings.TrimSpace(arg)
if strings.Contains(arg, "=") {
parts := strings.SplitN(arg, "=", 2)
- key, _, err := lexer.ProcessWord(parts[0], shell.EnvsFromSlice(args))
+ key, _, err := lexer.ProcessWord(parts[0], shell.EnvsFromSlice(argsCopy))
if err != nil {
return nil, fmt.Errorf("processing %q: %w", line, err)
}
- val, _, err := lexer.ProcessWord(parts[1], shell.EnvsFromSlice(args))
- if err != nil {
- return nil, fmt.Errorf("processing %q: %w", line, err)
+
+ // Only use the default value if no build arg was provided
+ if _, exists := buildArgsMap[key]; !exists {
+ val, _, err := lexer.ProcessWord(parts[1], shell.EnvsFromSlice(argsCopy))
+ if err != nil {
+ return nil, fmt.Errorf("processing %q: %w", line, err)
+ }
+ argsCopy = append(argsCopy, key+"="+val)
}
- args = append(args, key+"="+val)
}
continue
}
@@ -421,7 +495,7 @@ func ImageFromDockerfile(dockerfileContent string) (name.Reference, error) {
if imageRef == "" {
return nil, fmt.Errorf("no FROM directive found")
}
- imageRef, _, err := lexer.ProcessWord(imageRef, shell.EnvsFromSlice(args))
+ imageRef, _, err := lexer.ProcessWord(imageRef, shell.EnvsFromSlice(argsCopy))
if err != nil {
return nil, fmt.Errorf("processing %q: %w", imageRef, err)
}
diff --git a/devcontainer/devcontainer_test.go b/devcontainer/devcontainer_test.go
index 9582c99..6f9cd23 100644
--- a/devcontainer/devcontainer_test.go
+++ b/devcontainer/devcontainer_test.go
@@ -224,13 +224,76 @@ func TestImageFromDockerfile(t *testing.T) {
func TestImageFromDockerfileWithArgs(t *testing.T) {
t.Parallel()
for _, tc := range []struct {
+ default_image string
+ content string
+ image string
+ }{{
+ default_image: "mcr.microsoft.com/devcontainers/python:1-3-bookworm",
+ content: "ARG VARIANT=3-bookworm\nFROM mcr.microsoft.com/devcontainers/python:1-${VARIANT}",
+ image: "mcr.microsoft.com/devcontainers/python:1-3.11-bookworm",
+ }, {
+ default_image: "mcr.microsoft.com/devcontainers/python:1-3.10",
+ content: "ARG VARIANT=\"3.10\"\nFROM mcr.microsoft.com/devcontainers/python:1-$VARIANT",
+ image: "mcr.microsoft.com/devcontainers/python:1-3.11-bookworm",
+ }, {
+ default_image: "mcr.microsoft.com/devcontainers/python:1-3.10",
+ content: "ARG VARIANT=\"3.10\"\nFROM mcr.microsoft.com/devcontainers/python:1-$VARIANT\nUSER app",
+ image: "mcr.microsoft.com/devcontainers/python:1-3.11-bookworm",
+ }} {
+ tc := tc
+ t.Run(tc.image, func(t *testing.T) {
+ t.Parallel()
+ dc := &devcontainer.Spec{
+ Build: devcontainer.BuildSpec{
+ Dockerfile: "Dockerfile",
+ Context: ".",
+ Args: map[string]string{
+ "VARIANT": "3.11-bookworm",
+ },
+ },
+ }
+ fs := memfs.New()
+ dcDir := "/workspaces/coder/.devcontainer"
+ err := fs.MkdirAll(dcDir, 0o755)
+ require.NoError(t, err)
+ file, err := fs.OpenFile(filepath.Join(dcDir, "Dockerfile"), os.O_CREATE|os.O_WRONLY, 0o644)
+ require.NoError(t, err)
+ _, err = io.WriteString(file, tc.content)
+ require.NoError(t, err)
+ _ = file.Close()
+ params, err := dc.Compile(fs, dcDir, workingDir, "", "/var/workspace", false, stubLookupEnv)
+ require.NoError(t, err)
+ require.Equal(t, "VARIANT=3.11-bookworm", params.BuildArgs[0])
+ require.Equal(t, params.DockerfileContent, tc.content)
+ ref, err := devcontainer.ImageFromDockerfile(tc.content, params.BuildArgs)
+ require.NoError(t, err)
+ require.Equal(t, tc.image, ref.Name())
+ // Test without args (using defaults)
+ fmt.Println("Testing ImageFromDockerfile without args...")
+ ref1, err := devcontainer.ImageFromDockerfile(tc.content)
+ require.NoError(t, err)
+ require.Equal(t, tc.default_image, ref1.Name())
+ })
+ }
+}
+
+func TestUserFromDockerfileWithArgs(t *testing.T) {
+ t.Parallel()
+ for _, tc := range []struct {
+ user string
content string
image string
}{{
+ user: "root",
content: "ARG VARIANT=3-bookworm\nFROM mcr.microsoft.com/devcontainers/python:1-${VARIANT}",
image: "mcr.microsoft.com/devcontainers/python:1-3.11-bookworm",
}, {
- content: "ARG VARIANT=\"3.10\"\nFROM mcr.microsoft.com/devcontainers/python:1-$VARIANT ",
+ user: "root",
+ content: "ARG VARIANT=\"3.10\"\nFROM mcr.microsoft.com/devcontainers/python:1-$VARIANT",
+ image: "mcr.microsoft.com/devcontainers/python:1-3.11-bookworm",
+ }, {
+ user: "app",
+ content: "ARG VARIANT=\"3.10\"\nFROM mcr.microsoft.com/devcontainers/python:1-$VARIANT\nUSER app",
image: "mcr.microsoft.com/devcontainers/python:1-3.11-bookworm",
}} {
tc := tc
@@ -258,9 +321,17 @@ func TestImageFromDockerfileWithArgs(t *testing.T) {
require.NoError(t, err)
require.Equal(t, "VARIANT=3.11-bookworm", params.BuildArgs[0])
require.Equal(t, params.DockerfileContent, tc.content)
- ref, err := devcontainer.ImageFromDockerfile(tc.content)
+ // Test UserFromDockerfile without args
+ fmt.Println("\nTesting UserFromDockerfile without args...")
+ user1, err := devcontainer.UserFromDockerfile(tc.content)
require.NoError(t, err)
- require.Equal(t, tc.image, ref.Name())
+ require.Equal(t, tc.user, user1)
+ // Test UserFromDockerfile with args
+ fmt.Println("\nTesting UserFromDockerfile with args...")
+ user2, err := devcontainer.UserFromDockerfile(tc.content, params.BuildArgs)
+ require.NoError(t, err)
+ require.Equal(t, tc.user, user2)
+
})
}
}
diff --git a/envbuilder.go b/envbuilder.go
index ad2c84f..df90227 100644
--- a/envbuilder.go
+++ b/envbuilder.go
@@ -493,7 +493,7 @@ func run(ctx context.Context, opts options.Options, execArgs *execArgsInfo) erro
defer cleanupBuildContext()
if runtimeData.Built && opts.SkipRebuild {
endStage := startStage("🏗️ Skipping build because of cache...")
- imageRef, err := devcontainer.ImageFromDockerfile(buildParams.DockerfileContent)
+ imageRef, err := devcontainer.ImageFromDockerfile(buildParams.DockerfileContent, buildParams.BuildArgs)
if err != nil {
return nil, fmt.Errorf("image from dockerfile: %w", err)
}
From 85a20eb7028631bb4cab43fa1a607272693b8d38 Mon Sep 17 00:00:00 2001
From: twsl <45483159+twsl@users.noreply.github.com>
Date: Sat, 24 May 2025 21:38:58 +0000
Subject: [PATCH 8/8] Fix format
---
devcontainer/devcontainer_test.go | 1 -
1 file changed, 1 deletion(-)
diff --git a/devcontainer/devcontainer_test.go b/devcontainer/devcontainer_test.go
index 6f9cd23..650703c 100644
--- a/devcontainer/devcontainer_test.go
+++ b/devcontainer/devcontainer_test.go
@@ -331,7 +331,6 @@ func TestUserFromDockerfileWithArgs(t *testing.T) {
user2, err := devcontainer.UserFromDockerfile(tc.content, params.BuildArgs)
require.NoError(t, err)
require.Equal(t, tc.user, user2)
-
})
}
}