Support setting Python version when generating Dockerfile

main.go

@@ -65,9 +65,6 @@ func main() {
 
 	ctx := context.Background()
 	if err := app.Run(ctx, os.Args); err != nil {
-		style.Print(
-			fmt.Sprintf("\n\nERROR: %s", err),
-			&style.PrintOptions{Color: "red"},
-		)
+		style.PrintError(fmt.Sprintf("\n\nERROR: %s", err))
 	}
 }

pkg/build/Dockerfile.python.tmpl

@@ -1,4 +1,4 @@
-FROM ghcr.io/astral-sh/uv:python3.12-bookworm-slim AS build
+FROM ghcr.io/astral-sh/uv:python{{ .PythonVersion }}-bookworm-slim AS build
 LABEL maintainer="[email protected]"
 
 ENV UV_COMPILE_BYTECODE=1 UV_LINK_MODE=copy
@@ -16,7 +16,7 @@ RUN --mount=type=cache,target=/root/.cache/uv \
     uv sync --frozen --no-dev
 
 
-FROM python:3.12-slim-bookworm
+FROM python:{{ .PythonVersion }}-slim-bookworm
 LABEL maintainer="[email protected]"
 
 RUN addgroup application-group --gid 1001 && \

pkg/build/_test/Dockerfile.python.test1

@@ -0,0 +1,39 @@
+FROM ghcr.io/astral-sh/uv:python3.13-bookworm-slim AS build
+LABEL maintainer="[email protected]"
+
+ENV UV_COMPILE_BYTECODE=1 UV_LINK_MODE=copy
+
+WORKDIR /app
+
+RUN --mount=type=cache,target=/root/.cache/uv \
+    --mount=type=bind,source=uv.lock,target=uv.lock \
+    --mount=type=bind,source=pyproject.toml,target=pyproject.toml \
+    uv sync --frozen --no-install-project --no-dev
+
+ADD . /app
+
+RUN --mount=type=cache,target=/root/.cache/uv \
+    uv sync --frozen --no-dev
+
+
+FROM python:3.13-slim-bookworm
+LABEL maintainer="[email protected]"
+
+RUN addgroup application-group --gid 1001 && \
+    adduser application-user --uid 1001 \
+        --ingroup application-group \
+        --disabled-password
+
+WORKDIR /app
+
+COPY --from=build /app .
+
+ENV PATH="/app/.venv/bin:$PATH"
+
+RUN chown --recursive application-user .
+USER application-user
+
+EXPOSE 8080
+
+CMD ["fastapi", "run", "--host", "0.0.0.0", "--port", "8080", "/app/app/main.py"]
+

pkg/build/_test/Dockerfile.python.test3

@@ -0,0 +1,39 @@
+FROM ghcr.io/astral-sh/uv:python3.10-bookworm-slim AS build
+LABEL maintainer="[email protected]"
+
+ENV UV_COMPILE_BYTECODE=1 UV_LINK_MODE=copy
+
+WORKDIR /app
+
+RUN --mount=type=cache,target=/root/.cache/uv \
+    --mount=type=bind,source=uv.lock,target=uv.lock \
+    --mount=type=bind,source=pyproject.toml,target=pyproject.toml \
+    uv sync --frozen --no-install-project --no-dev
+
+ADD . /app
+
+RUN --mount=type=cache,target=/root/.cache/uv \
+    uv sync --frozen --no-dev
+
+
+FROM python:3.10-slim-bookworm
+LABEL maintainer="[email protected]"
+
+RUN addgroup application-group --gid 1001 && \
+    adduser application-user --uid 1001 \
+        --ingroup application-group \
+        --disabled-password
+
+WORKDIR /app
+
+COPY --from=build /app .
+
+ENV PATH="/app/.venv/bin:$PATH"
+
+RUN chown --recursive application-user .
+USER application-user
+
+EXPOSE 8080
+
+CMD ["fastapi", "run", "--host", "0.0.0.0", "--port", "8080", "/app/app/main.py"]
+

pkg/build/build.go

@@ -129,9 +129,8 @@ func Build(_ context.Context, c *cli.Command) error {
 		possibleSystemName := c.String("system-name")
 
 		if possibleSystemName == "" {
-			style.Print(
+			style.PrintInfo(
 				"System name not provided, will try to use the current git repository name.",
-				nil,
 			)
 
 			repositoryName, err := utils.ResolveRepositoryName("")
@@ -163,9 +162,8 @@ func Build(_ context.Context, c *cli.Command) error {
 	}
 
 	if c.Bool("generate-only") {
-		style.Print(
+		style.PrintSuccess(
 			fmt.Sprintf("Dockerfile generated at %s\n", dockerfilePath),
-			nil,
 		)
 
 		return nil
@@ -178,7 +176,7 @@ func Build(_ context.Context, c *cli.Command) error {
 	skipAuthentication := c.Bool("skip-authentication") || !push
 
 	if strings.Contains(registry, "azurecr.io") && !skipAuthentication {
-		style.Print("Azure registry detected, will try to authenticate with Azure.", nil)
+		style.PrintInfo("Azure registry detected, will try to authenticate with Azure.")
 
 		azureTenantID := utils.StringWithDefault(
 			c.String("azure-tenant-id"),

pkg/build/generate.go

@@ -49,14 +49,6 @@ func generateDockerfile(
 		}
 
 		return dockerfile, buildContext, nil
-	} else if strings.HasPrefix(projectFile, "Dockerfile") ||
-		strings.HasSuffix(projectFile, "Dockerfile") ||
-		strings.Contains(projectFile, "Dockerfile") {
-		if options.BuildContext == "" {
-			return projectFile, path.Dir(projectFile), nil
-		}
-
-		return projectFile, options.BuildContext, nil
 	} else if strings.HasSuffix(projectFile, "uv.lock") {
 		dockerfile, buildContext, err := generateDockerfileForPython(
 			projectFile,
@@ -68,6 +60,14 @@ func generateDockerfile(
 		}
 
 		return dockerfile, buildContext, nil
+	} else if strings.HasPrefix(projectFile, "Dockerfile") ||
+		strings.HasSuffix(projectFile, "Dockerfile") ||
+		strings.Contains(projectFile, "Dockerfile") {
+		if options.BuildContext == "" {
+			return projectFile, path.Dir(projectFile), nil
+		}
+
+		return projectFile, options.BuildContext, nil
 	}
 
 	return "", "", fmt.Errorf(

pkg/build/generate_python.go

@@ -1,10 +1,20 @@
 package build
 
 import (
+	"fmt"
+	"io"
+	"os"
+	"path"
+	"slices"
+	"strings"
+
+	"github.com/3lvia/cli/pkg/style"
 	"github.com/3lvia/cli/pkg/utils"
 )
 
-type DockerfileVariablesPython struct{}
+type DockerfileVariablesPython struct {
+	PythonVersion string
+}
 
 func generateDockerfileForPython(
 	projectFile string,
@@ -16,7 +26,14 @@ func generateDockerfileForPython(
 		options.BuildContext,
 	)
 
-	dockerfileVariables := DockerfileVariablesPython{}
+	pythonVersion := getPythonVersion(
+		path.Dir(projectFile),
+		buildContext,
+	)
+
+	dockerfileVariables := DockerfileVariablesPython{
+		PythonVersion: pythonVersion,
+	}
 
 	const templateFile = "Dockerfile.python.tmpl"
 
@@ -33,3 +50,80 @@ func generateDockerfileForPython(
 
 	return dockerfilePath, buildContext, nil
 }
+
+func getPythonVersion(directories ...string) string {
+	const defaultPythonVersion = "3.13"
+
+	// removes duplicates
+	slices.Sort(directories)
+	directories = slices.Compact(directories)
+
+	style.PrintInfo(
+		fmt.Sprintf(
+			"Looking for .python-version file in directories: '%v'.",
+			strings.Join(directories, ", "),
+		),
+	)
+
+	for _, directory := range directories {
+		versionFile := path.Join(directory, ".python-version")
+
+		if _, err := os.Stat(versionFile); os.IsNotExist(err) {
+			style.PrintWarning(
+				fmt.Sprintf(
+					"No .python-version file found in '%s', will try next directory.\n",
+					directory,
+				),
+			)
+
+			continue
+		}
+
+		file, err := os.Open(versionFile)
+		if err != nil {
+			style.PrintWarning(
+				fmt.Sprintf(
+					"Failed to open .python-version file in '%s', will try next directory.\n",
+					directory,
+				),
+			)
+
+			continue
+		}
+
+		defer file.Close()
+
+		contents, err := io.ReadAll(file)
+		if err != nil {
+			style.PrintWarning(
+				fmt.Sprintf(
+					"Failed to read .python-version file in '%s', will try next directory.\n",
+					directory,
+				),
+			)
+
+			continue
+		}
+
+		pythonVersion := strings.TrimSpace(string(contents))
+
+		style.PrintInfo(
+			fmt.Sprintf(
+				"Found .python-version file in '%s' with version %s.\n",
+				directory,
+				pythonVersion,
+			),
+		)
+
+		return pythonVersion
+	}
+
+	style.PrintWarning(
+		fmt.Sprintf(
+			"Did not find any .python-version files, using default version %s.",
+			defaultPythonVersion,
+		),
+	)
+
+	return defaultPythonVersion
+}

pkg/build/generate_test.go

@@ -3,6 +3,7 @@ package build
 import (
 	"os"
 	"path/filepath"
+	"strconv"
 	"testing"
 )
 
@@ -296,10 +297,10 @@ func TestGenerateGoDockerfile(t *testing.T) {
 	}
 }
 
-func TestGeneratePythonDockerfile(t *testing.T) {
+func TestGeneratePythonDockerfile1(t *testing.T) {
 	t.Parallel()
 
-	expectedDockerfile, err := os.ReadFile("_test/Dockerfile.python.test")
+	expectedDockerfile, err := os.ReadFile("_test/Dockerfile.python.test1")
 	if err != nil {
 		t.Errorf("Error reading file: %v", err)
 	}
@@ -334,6 +335,54 @@ func TestGeneratePythonDockerfile(t *testing.T) {
 	}
 }
 
+func TestGeneratePythonDockerfile2(t *testing.T) {
+	t.Parallel()
+
+	for i, version := range []string{"3.12", "3.10"} {
+		expectedDockerfile, err := os.ReadFile("_test/Dockerfile.python.test" + strconv.FormatInt(int64(i+2), 10))
+		if err != nil {
+			t.Errorf("Error reading file: %v", err)
+		}
+
+		tempDir := t.TempDir()
+		projectFile := filepath.Join(tempDir, "uv.lock")
+		expectedBuildContext := tempDir
+
+		const applicationName = "demo-api-python"
+
+		file, err := os.Create(filepath.Join(tempDir, ".python-version"))
+		if err != nil {
+			t.Errorf("Error creating file: %v", err)
+		}
+
+		if _, err := file.WriteString(version + "\n"); err != nil {
+			t.Errorf("Error writing to file: %v", err)
+		}
+
+		actualDockerfilePath, actualBuildContext, err := generateDockerfile(
+			projectFile,
+			applicationName,
+			GenerateDockerfileOptions{},
+		)
+		if err != nil {
+			t.Errorf("Error generating Dockerfile: %v", err)
+		}
+
+		actualDockerfile, err := os.ReadFile(actualDockerfilePath)
+		if err != nil {
+			t.Errorf("Error reading file: %v", err)
+		}
+
+		if string(expectedDockerfile) != string(actualDockerfile) {
+			t.Errorf("Dockerfile mismatch: expected %s, got %s", expectedDockerfile, actualDockerfile)
+		}
+
+		if expectedBuildContext != actualBuildContext {
+			t.Errorf("Build context mismatch: expected %s, got %s", expectedBuildContext, actualBuildContext)
+		}
+	}
+}
+
 func TestGenerateDockerfileWithDockerfile1(t *testing.T) {
 	t.Parallel()
 

pkg/create/create.go

@@ -132,20 +132,14 @@ func Create(ctx context.Context, c *cli.Command) error {
 				log.Fatal("pipx, which is required for installing cookiecutter, is not installed. Please install it first.")
 			}
 
-			style.Print(
-				"Installing cookiecutter...",
-				nil,
-			)
+			style.PrintInfo("Installing cookiecutter...")
 
 			installCookiecutterOutput := installCookiecutterCommand(nil)
 			if command.IsError(installCookiecutterOutput) {
 				return cli.Exit("Failed to install cookiecutter.", 1)
 			}
 
-			style.Print(
-				"Cookiecutter installed!",
-				&style.PrintOptions{Color: "green"},
-			)
+			style.PrintSuccess("Cookiecutter installed!")
 		} else {
 			return cli.Exit("Cookiecutter is required for creating a new project. Please install it first.", 1)
 		}
@@ -200,10 +194,7 @@ func Create(ctx context.Context, c *cli.Command) error {
 		return cli.Exit(err, 1)
 	}
 
-	style.Print(
-		fmt.Sprintf("Successfully created project at '%s'!", projectDirectory),
-		&style.PrintOptions{Color: "green"},
-	)
+	style.PrintSuccess(fmt.Sprintf("Successfully created project at '%s'!", projectDirectory))
 
 	return nil
 }