read lambroll.json(net) as default options.

refs #449

README.md

@@ -196,6 +196,49 @@ Commands:
 Run "lambroll <command> --help" for more information on a command.
 ```
 
+### Global flags
+
+lambroll has global flags for all commands.
+
+These flags can be set by environment variables or option file (`lambroll.json` or `lambroll.jsonnet`).
+
+#### Environment variables
+
+For example, `--log-level=debug` can be set by `LAMBROLL_LOGLEVEL=debug`.
+
+See the above usage for the environment variable names.
+
+#### Option file
+
+`lambroll.json` or `lambroll.jsonnet` can be used as an option file.
+
+If the option file is found in the current directory, lambroll reads the file and applies the options.
+
+```jsonnet
+{
+  logLevel: 'info',
+  color: true,
+  region: 'ap-northeast-1',
+  profile: 'default',
+  tfstate: 's3://my-bucket/terraform.tfstate',
+  prefixedTfstate: {
+    my_first_: 's3://my-bucket/first.tfstate',
+    my_second_: 's3://my-bucket/second.tfstate',
+  },
+  endpoint: 'http://localhost:9001',
+  envfile: ['.env1', '.env2'],
+  extStr: {
+    accountID: '0123456789012',
+  },
+  extCode: {
+    memorySize: '128 * 4',
+  },
+}
+```
+
+All fields are optional. If the field is not defined, the default value is used.
+When passed by command line options, the command line option takes precedence over the option file.
+
 ### Init
 
 `lambroll init` initialize function.json by existing function.

cli.go

@@ -1,7 +1,10 @@
 package lambroll
 
 import (
+	"bytes"
 	"context"
+	"encoding/json"
+	"errors"
 	"fmt"
 	"log"
 	"os"
@@ -13,18 +16,18 @@ import (
 )
 
 type Option struct {
-	Function string `help:"Function file path" env:"LAMBROLL_FUNCTION"`
-	LogLevel string `help:"log level (trace, debug, info, warn, error)" default:"info" enum:"trace,debug,info,warn,error" env:"LAMBROLL_LOGLEVEL"`
-	Color    bool   `help:"enable colored output" default:"true" env:"LAMBROLL_COLOR" negatable:""`
-
-	Region          *string           `help:"AWS region" env:"AWS_REGION"`
-	Profile         *string           `help:"AWS credential profile name" env:"AWS_PROFILE"`
-	TFState         *string           `name:"tfstate" help:"URL to terraform.tfstate" env:"LAMBROLL_TFSTATE"`
-	PrefixedTFState map[string]string `name:"prefixed-tfstate" help:"key value pair of the prefix for template function name and URL to terraform.tfstate" env:"LAMBROLL_PREFIXED_TFSTATE"`
-	Endpoint        *string           `help:"AWS API Lambda Endpoint" env:"AWS_LAMBDA_ENDPOINT"`
-	Envfile         []string          `help:"environment files" env:"LAMBROLL_ENVFILE"`
-	ExtStr          map[string]string `help:"external string values for Jsonnet" env:"LAMBROLL_EXTSTR"`
-	ExtCode         map[string]string `help:"external code values for Jsonnet" env:"LAMBROLL_EXTCODE"`
+	Function string `help:"Function file path" env:"LAMBROLL_FUNCTION" json:"function,omitempty"`
+	LogLevel string `help:"log level (trace, debug, info, warn, error)" default:"info" enum:",trace,debug,info,warn,error" env:"LAMBROLL_LOGLEVEL" json:"log_level"`
+	Color    bool   `help:"enable colored output" default:"true" env:"LAMBROLL_COLOR" negatable:"" json:"color,omitempty"`
+
+	Region          *string           `help:"AWS region" env:"AWS_REGION" json:"region,omitempty"`
+	Profile         *string           `help:"AWS credential profile name" env:"AWS_PROFILE" json:"profile,omitempty"`
+	TFState         *string           `name:"tfstate" help:"URL to terraform.tfstate" env:"LAMBROLL_TFSTATE" json:"tfstate,omitempty"`
+	PrefixedTFState map[string]string `name:"prefixed-tfstate" help:"key value pair of the prefix for template function name and URL to terraform.tfstate" env:"LAMBROLL_PREFIXED_TFSTATE" json:"prefixed_tfstate,omitempty"`
+	Endpoint        *string           `help:"AWS API Lambda Endpoint" env:"AWS_LAMBDA_ENDPOINT" json:"endpoint,omitempty"`
+	Envfile         []string          `help:"environment files" env:"LAMBROLL_ENVFILE" json:"envfile,omitempty"`
+	ExtStr          map[string]string `help:"external string values for Jsonnet" env:"LAMBROLL_EXTSTR" json:"extstr,omitempty"`
+	ExtCode         map[string]string `help:"external code values for Jsonnet" env:"LAMBROLL_EXTCODE" json:"extcode,omitempty"`
 }
 
 type CLIOptions struct {
@@ -54,8 +57,30 @@ func ParseCLI(args []string) (string, *CLIOptions, func(), error) {
 		args = []string{"--help"}
 	}
 
+	kongOpts := []kong.Option{kong.Vars{"version": Version}}
+
+	// load default options from lambroll.json or .jsonnet
+	defaultOpt, err := loadDefinitionFile[Option](nil, "", DefaultOptionFilenames)
+	if err != nil {
+		if errors.Is(err, os.ErrNotExist) {
+			// ignore not found error
+		} else {
+			return "", nil, nil, fmt.Errorf("failed to load default options: %w", err)
+		}
+	} else {
+		defaultOptBytes, err := json.Marshal(defaultOpt)
+		if err != nil {
+			return "", nil, nil, fmt.Errorf("failed to marshal default options: %w", err)
+		}
+		resolver, err := kong.JSON(bytes.NewReader(defaultOptBytes))
+		if err != nil {
+			return "", nil, nil, fmt.Errorf("failed to parse default options: %w", err)
+		}
+		kongOpts = append(kongOpts, kong.Resolvers(resolver))
+	}
+
 	var opts CLIOptions
-	parser, err := kong.New(&opts, kong.Vars{"version": Version})
+	parser, err := kong.New(&opts, kongOpts...)
 	if err != nil {
 		return "", nil, nil, fmt.Errorf("failed to new kong: %w", err)
 	}
@@ -74,6 +99,9 @@ func CLI(ctx context.Context, parse CLIParseFunc) (int, error) {
 	}
 
 	color.NoColor = !opts.Color
+	if opts.LogLevel == "" {
+		opts.LogLevel = DefaultLogLevel
+	}
 	filter := &logutils.LevelFilter{
 		Levels: []logutils.LogLevel{"trace", "debug", "info", "warn", "error"},
 		ModifierFuncs: []logutils.ModifierFunc{

lambroll.go

@@ -6,6 +6,7 @@ import (
 	"log"
 	"os"
 	"path/filepath"
+	"reflect"
 	"text/template"
 	"time"
 
@@ -53,6 +54,9 @@ func (app *App) functionArn(ctx context.Context, name string) string {
 }
 
 var (
+	// DefaultLogLevel is default log level
+	DefaultLogLevel = "info"
+
 	// IgnoreFilename defines file name includes ignore patterns at creating zip archive.
 	IgnoreFilename = ".lambdaignore"
 
@@ -62,11 +66,18 @@ var (
 		"function.jsonnet",
 	}
 
+	// DefaultFunctionURLFilenames defines file name for function URL definition.
 	DefaultFunctionURLFilenames = []string{
 		"function_url.json",
 		"function_url.jsonnet",
 	}
 
+	// DefaultOptionFilenames defines file name for option definition.
+	DefaultOptionFilenames = []string{
+		"lambroll.json",
+		"lambroll.jsonnet",
+	}
+
 	// FunctionZipFilename defines file name for zip archive downloaded at init.
 	FunctionZipFilename = "function.zip"
 
@@ -77,6 +88,8 @@ var (
 		DefaultFunctionFilenames[1],
 		DefaultFunctionURLFilenames[0],
 		DefaultFunctionURLFilenames[1],
+		DefaultOptionFilenames[0],
+		DefaultOptionFilenames[1],
 		FunctionZipFilename,
 		".git/*",
 		".terraform/*",
@@ -222,6 +235,9 @@ func loadDefinitionFile[T any](app *App, path string, defaults []string) (*T, er
 		}
 		path = p
 	}
+	var instance T
+	typeName := reflect.TypeOf(instance).Name()
+	log.Printf("[info] loading %s from %s", typeName, path)
 
 	var (
 		src []byte
@@ -230,27 +246,41 @@ func loadDefinitionFile[T any](app *App, path string, defaults []string) (*T, er
 	switch filepath.Ext(path) {
 	case ".jsonnet":
 		vm := jsonnet.MakeVM()
-		for _, f := range app.nativeFuncs {
-			vm.NativeFunction(f)
-		}
-		for k, v := range app.extStr {
-			vm.ExtVar(k, v)
-		}
-		for k, v := range app.extCode {
-			vm.ExtCode(k, v)
+		if app != nil {
+			for _, f := range app.nativeFuncs {
+				vm.NativeFunction(f)
+			}
+			for k, v := range app.extStr {
+				vm.ExtVar(k, v)
+			}
+			for k, v := range app.extCode {
+				vm.ExtCode(k, v)
+			}
 		}
 		jsonStr, err := vm.EvaluateFile(path)
 		if err != nil {
 			return nil, err
 		}
-		src, err = app.loader.ReadWithEnvBytes([]byte(jsonStr))
-		if err != nil {
-			return nil, err
+		if app != nil {
+			src, err = app.loader.ReadWithEnvBytes([]byte(jsonStr))
+			if err != nil {
+				return nil, err
+			}
+		} else {
+			// no app, just return jsonnet result
+			src = []byte(jsonStr)
 		}
 	default:
-		src, err = app.loader.ReadWithEnv(path)
-		if err != nil {
-			return nil, err
+		if app != nil {
+			src, err = app.loader.ReadWithEnv(path)
+			if err != nil {
+				return nil, err
+			}
+		} else {
+			src, err = os.ReadFile(path)
+			if err != nil {
+				return nil, err
+			}
 		}
 	}
 	var v T

utils.go

@@ -99,7 +99,7 @@ func findDefinitionFile(preferred string, defaults []string) (string, error) {
 			return name, nil
 		}
 	}
-	return "", fmt.Errorf("function file (%s) not found", strings.Join(DefaultFunctionFilenames, " or "))
+	return "", fmt.Errorf("file (%s) not found: %w", strings.Join(DefaultFunctionFilenames, " or "), os.ErrNotExist)
 }
 
 func jsonToJsonnet(src []byte, filepath string) ([]byte, error) {