Pass buildArgs to ACR remote build task (#7997)

* Pass buildArgs to ACR remote build task

Docker buildArgs and buildEnv defined in azure.yaml were silently dropped when `remoteBuild: true` was set because runRemoteBuild never forwarded them to the ACR DockerBuildRequest.

Resolve buildArgs (with environment variable substitution and parameter resolution) and buildEnv the same way the local Docker build does, then convert each entry into an armcontainerregistry.Argument and attach it to the build request. Shorthand `NAME` entries are looked up from os.Environ, the azd environment, and buildEnv (in increasing precedence).

The shared resolution logic is extracted into resolveDockerBuildArgs / resolveDockerParameters so local and remote builds stay in sync.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Address PR feedback: fix stale comment, preallocate slice, clarify error

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

---------

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: JeffreyCA

cli/azd/pkg/project/container_helper.go

@@ -356,42 +356,13 @@ func (ch *ContainerHelper) Build(
 	dockerOptions := getDockerOptionsWithDefaults(serviceConfig.Docker)
 	resolveDockerPaths(serviceConfig, &dockerOptions)
 
-	resolveParameters := func(source []string) ([]string, error) {
-		result := make([]string, len(source))
-		for i, arg := range source {
-			evaluatedString, err := apphost.EvalString(arg, func(match string) (string, error) {
-				path := match
-				value, has := env.Config.GetString(path)
-				if !has {
-					return "", fmt.Errorf("parameter %s not found", path)
-				}
-				return value, nil
-			})
-			if err != nil {
-				return nil, err
-			}
-			result[i] = evaluatedString
-		}
-		return result, nil
-	}
-
-	dockerBuildArgs := []string{}
-	for _, arg := range dockerOptions.BuildArgs {
-		buildArgValue, err := arg.Envsubst(env.Getenv)
-		if err != nil {
-			return nil, fmt.Errorf("substituting environment variables in build args: %w", err)
-		}
-
-		dockerBuildArgs = append(dockerBuildArgs, buildArgValue)
-	}
-
-	// resolve parameters for build args and secrets
-	resolvedBuildArgs, err := resolveParameters(dockerBuildArgs)
+	resolvedBuildArgs, err := resolveDockerBuildArgs(dockerOptions.BuildArgs, env)
 	if err != nil {
 		return nil, err
 	}
 
-	resolvedBuildEnv, err := resolveParameters(dockerOptions.BuildEnv)
+	// resolve parameters for build env
+	resolvedBuildEnv, err := resolveDockerParameters(dockerOptions.BuildEnv, env)
 	if err != nil {
 		return nil, err
 	}
@@ -525,6 +496,40 @@ func (ch *ContainerHelper) Build(
 	}, nil
 }
 
+func resolveDockerBuildArgs(buildArgs []osutil.ExpandableString, env *environment.Environment) ([]string, error) {
+	dockerBuildArgs := make([]string, 0, len(buildArgs))
+	for _, arg := range buildArgs {
+		buildArgValue, err := arg.Envsubst(env.Getenv)
+		if err != nil {
+			return nil, fmt.Errorf("substituting environment variables in build args: %w", err)
+		}
+
+		dockerBuildArgs = append(dockerBuildArgs, buildArgValue)
+	}
+
+	return resolveDockerParameters(dockerBuildArgs, env)
+}
+
+func resolveDockerParameters(source []string, env *environment.Environment) ([]string, error) {
+	result := make([]string, len(source))
+	for i, arg := range source {
+		evaluatedString, err := apphost.EvalString(arg, func(match string) (string, error) {
+			path := match
+			value, has := env.Config.GetString(path)
+			if !has {
+				return "", fmt.Errorf("parameter %s not found", path)
+			}
+			return value, nil
+		})
+		if err != nil {
+			return nil, err
+		}
+		result[i] = evaluatedString
+	}
+
+	return result, nil
+}
+
 func (ch *ContainerHelper) Package(
 	ctx context.Context,
 	serviceConfig *ServiceConfig,
@@ -812,6 +817,24 @@ func (ch *ContainerHelper) runRemoteBuild(
 		return "", fmt.Errorf("remote build only supports the linux/amd64 platform")
 	}
 
+	resolvedBuildArgs, err := resolveDockerBuildArgs(dockerOptions.BuildArgs, env)
+	if err != nil {
+		return "", err
+	}
+
+	resolvedBuildEnv, err := resolveDockerParameters(dockerOptions.BuildEnv, env)
+	if err != nil {
+		return "", err
+	}
+
+	acrBuildArgs, err := dockerBuildArgsToAcrArguments(
+		resolvedBuildArgs,
+		dockerBuildArgEnvResolver(env, resolvedBuildEnv),
+	)
+	if err != nil {
+		return "", err
+	}
+
 	progress.SetProgress(NewServiceProgress("Packing remote build context"))
 
 	contextPath, dockerPath, err := containerregistry.PackRemoteBuildSource(ctx, dockerOptions.Context, dockerOptions.Path)
@@ -872,6 +895,9 @@ func (ch *ContainerHelper) runRemoteBuild(
 			Architecture: to.Ptr(armcontainerregistry.ArchitectureAmd64),
 		},
 	}
+	if len(acrBuildArgs) > 0 {
+		buildRequest.Arguments = acrBuildArgs
+	}
 
 	previewerWriter := ch.console.ShowPreviewer(ctx,
 		&input.ShowPreviewerOptions{
@@ -889,6 +915,75 @@ func (ch *ContainerHelper) runRemoteBuild(
 	return imageName, nil
 }
 
+func dockerBuildArgsToAcrArguments(
+	buildArgs []string,
+	lookupEnv func(string) (string, bool),
+) ([]*armcontainerregistry.Argument, error) {
+	if len(buildArgs) == 0 {
+		return nil, nil
+	}
+
+	acrArgs := make([]*armcontainerregistry.Argument, 0, len(buildArgs))
+	for i, arg := range buildArgs {
+		name, value, hasValue := strings.Cut(arg, "=")
+		if name == "" {
+			return nil, fmt.Errorf("docker build arg at index %d has an empty name", i)
+		}
+
+		if !hasValue {
+			var ok bool
+			value, ok = lookupEnv(name)
+			if !ok {
+				return nil, fmt.Errorf(
+					"resolving docker build arg %q for remote build: environment variable is not set; "+
+						"use %s=<value> or set environment variable %s",
+					name,
+					name,
+					name,
+				)
+			}
+		}
+
+		acrArgs = append(acrArgs, &armcontainerregistry.Argument{
+			Name:     new(name),
+			Value:    new(value),
+			IsSecret: new(false),
+		})
+	}
+
+	return acrArgs, nil
+}
+
+func dockerBuildArgEnvResolver(
+	env *environment.Environment,
+	buildEnv []string,
+) func(string) (string, bool) {
+	effectiveEnv := map[string]string{}
+	for _, envVar := range os.Environ() {
+		key, value, ok := strings.Cut(envVar, "=")
+		if ok {
+			effectiveEnv[key] = value
+		}
+	}
+	for _, envVar := range env.Environ() {
+		key, value, ok := strings.Cut(envVar, "=")
+		if ok {
+			effectiveEnv[key] = value
+		}
+	}
+	for _, envVar := range buildEnv {
+		key, value, ok := strings.Cut(envVar, "=")
+		if ok {
+			effectiveEnv[key] = value
+		}
+	}
+
+	return func(key string) (string, bool) {
+		value, ok := effectiveEnv[key]
+		return value, ok
+	}
+}
+
 // runDotnetPublish builds and publishes the container image using `dotnet publish`. It returns the full remote image name.
 func (ch *ContainerHelper) runDotnetPublish(
 	ctx context.Context,