feat: add conduit config (#2033)

* start working on config command

* start working on config command

* config cmd works

* implement config cmd

* refactor

* fix spelling

* fix lint

cmd/conduit/root/config.go

@@ -0,0 +1,88 @@
+// Copyright © 2024 Meroxa, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package root
+
+import (
+	"context"
+	"fmt"
+	"reflect"
+
+	"github.com/conduitio/ecdysis"
+)
+
+var (
+	_ ecdysis.CommandWithExecute = (*ConfigCommand)(nil)
+	_ ecdysis.CommandWithDocs    = (*ConfigCommand)(nil)
+	_ ecdysis.CommandWithFlags   = (*ConfigCommand)(nil)
+	_ ecdysis.CommandWithConfig  = (*ConfigCommand)(nil)
+)
+
+type ConfigCommand struct {
+	rootCmd *RootCommand
+}
+
+func (c *ConfigCommand) Config() ecdysis.Config {
+	return c.rootCmd.Config()
+}
+
+func (c *ConfigCommand) Flags() []ecdysis.Flag {
+	return c.rootCmd.Flags()
+}
+
+func (c *ConfigCommand) Docs() ecdysis.Docs {
+	return ecdysis.Docs{
+		Short: "Shows the configuration to be used when running Conduit.",
+		Long: `Conduit will run based on the default configuration jointly with a provided configuration file (optional), 
+the set environment variables, and the flags used. This command will show the configuration that will be used.`,
+	}
+}
+
+func printStruct(v reflect.Value, parentPath string) {
+	if v.Kind() == reflect.Ptr {
+		v = v.Elem()
+	}
+
+	t := v.Type()
+	for i := 0; i < v.NumField(); i++ {
+		field := t.Field(i)
+		fieldValue := v.Field(i)
+		longName := field.Tag.Get("long")
+
+		fullPath := longName
+		if parentPath != "" && longName != "" {
+			fullPath = parentPath + "." + longName
+		}
+
+		if fieldValue.Kind() == reflect.Struct ||
+			(fieldValue.Kind() == reflect.Ptr && !fieldValue.IsNil() && fieldValue.Elem().Kind() == reflect.Struct) {
+			printStruct(fieldValue, fullPath)
+			continue
+		}
+
+		if longName != "" {
+			value := fmt.Sprintf("%v", fieldValue.Interface())
+			if value != "" {
+				fmt.Printf("%s: %s\n", fullPath, value)
+			}
+		}
+	}
+}
+
+func (c *ConfigCommand) Usage() string { return "config" }
+
+func (c ConfigCommand) Execute(_ context.Context) error {
+	printStruct(reflect.ValueOf(c.rootCmd.cfg), "")
+	return nil
+}

cmd/conduit/root/config_test.go

@@ -0,0 +1,76 @@
+// Copyright © 2024 Meroxa, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package root
+
+import (
+	"bytes"
+	"io"
+	"os"
+	"reflect"
+	"strings"
+	"testing"
+
+	"github.com/conduitio/conduit/pkg/conduit"
+	"github.com/matryer/is"
+)
+
+func TestPrintStructOutput(t *testing.T) {
+	is := is.New(t)
+
+	cfg := conduit.DefaultConfig()
+
+	oldStdout := os.Stdout
+	defer func() { os.Stdout = oldStdout }()
+
+	r, w, err := os.Pipe()
+	is.NoErr(err)
+
+	os.Stdout = w
+	t.Cleanup(func() { os.Stdout = oldStdout })
+
+	printStruct(reflect.ValueOf(cfg), "")
+
+	err = w.Close()
+	is.NoErr(err)
+
+	var buf bytes.Buffer
+	_, err = io.Copy(&buf, r)
+	is.NoErr(err)
+
+	output := buf.String()
+
+	expectedLines := []string{
+		"db.type: badger",
+		"db.postgres.table: conduit_kv_store",
+		"db.sqlite.table: conduit_kv_store",
+		"api.enabled: true",
+		"http.address: :8080",
+		"grpc.address: :8084",
+		"log.level: info",
+		"log.format: cli",
+		"pipelines.exit-on-degraded: false",
+		"pipelines.error-recovery.min-delay: 1s",
+		"pipelines.error-recovery.max-delay: 10m0s",
+		"pipelines.error-recovery.backoff-factor: 2",
+		"pipelines.error-recovery.max-retries: -1",
+		"pipelines.error-recovery.max-retries-window: 5m0s",
+		"schema-registry.type: builtin",
+		"preview.pipeline-arch-v2: false",
+	}
+
+	for _, line := range expectedLines {
+		is.True(strings.Contains(output, line))
+	}
+}

cmd/conduit/root/root.go

@@ -113,6 +113,9 @@ func (c *RootCommand) Docs() ecdysis.Docs {
 
 func (c *RootCommand) SubCommands() []ecdysis.Command {
 	return []ecdysis.Command{
+		&ConfigCommand{
+			rootCmd: c,
+		},
 		&InitCommand{cfg: &c.cfg},
 		&pipelines.PipelinesCommand{},
 	}