refactor es client config to have a common base config for elasticsearch url

CHANGELOG.md

@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+- Show error if ELASTICSEARCH_URL is not set when using credentials provider ([#68](https://github.com/hasura/ndc-elasticsearch/pull/68))
+
 ## [1.5.0]
 
 - Add support for a credentials provider service ([#65](https://github.com/hasura/ndc-elasticsearch/pull/65))

elasticsearch/config.go

@@ -19,29 +19,23 @@ var (
 	credentailsProviderKeyEnvVar       = "ELASTICSEARCH_CREDENTIALS_PROVIDER_KEY"
 	credentailsProviderMechanismEnvVar = "ELASTICSEARCH_CREDENTIALS_PROVIDER_MECHANISM"
 	credentialsProviderUri             = "HASURA_CREDENTIALS_PROVIDER_URI"
+	elasticsearchUrl                   = "ELASTICSEARCH_URL"
 )
 
 var (
 	errCredentialProviderKeyNotSet        = fmt.Errorf("%s is not set", credentailsProviderKeyEnvVar)
 	errCredentialProviderMechanismNotSet  = fmt.Errorf("%s is not set", credentailsProviderMechanismEnvVar)
 	errCredentialProviderMechanismInvalid = fmt.Errorf("invalid value for %s, should be either \"api-key\" or \"service-token\"", credentailsProviderMechanismEnvVar)
+	errElasticsearchUrlNotSet             = fmt.Errorf("%s is not set", elasticsearchUrl)
 )
 
 // getConfigFromEnv retrieves elastic search configuration from environment variables.
 func getConfigFromEnv() (*elasticsearch.Config, error) {
-	esConfig := elasticsearch.Config{}
-
-	// Read the address
-	address := os.Getenv("ELASTICSEARCH_URL")
-	if address == "" {
-		return nil, errors.New("ELASTICSEARCH_URL is not set")
+	esConfig, err := getBaseConfig()
+	if err != nil {
+		return nil, err
 	}
 
-	// Split the address by comma
-	addresses := make([]string, 0)
-	addresses = append(addresses, strings.Split(address, ",")...)
-	esConfig.Addresses = addresses
-
 	// Read the credentials if provided
 	username := os.Getenv("ELASTICSEARCH_USERNAME")
 	password := os.Getenv("ELASTICSEARCH_PASSWORD")
@@ -65,42 +59,52 @@ func getConfigFromEnv() (*elasticsearch.Config, error) {
 		esConfig.CACert = cert
 	}
 
-	return &esConfig, nil
+	return esConfig, nil
 }
 
 func shouldUseCredentialsProvider() bool {
 	return os.Getenv(credentialsProviderUri) != ""
 }
 
 func getConfigFromCredentialsProvider(ctx context.Context, forceRefresh bool) (*elasticsearch.Config, error) {
+	esConfig, err := getBaseConfig()
+	if err != nil {
+		return nil, err
+	}
+
 	key := os.Getenv(credentailsProviderKeyEnvVar)
 	mechanism := os.Getenv(credentailsProviderMechanismEnvVar)
-	return useCredentialsProvider(ctx, key, mechanism, forceRefresh)
+	err = setupCredentailsUsingCredentialsProvider(ctx, esConfig, key, mechanism, forceRefresh)
+	if err != nil {
+		return nil, err
+	}
+	return esConfig, nil
 }
 
-func useCredentialsProvider(ctx context.Context, key string, mechanism string, forceRefresh bool) (*elasticsearch.Config, error) {
+// setupCredentailsUsingCredentialsProvider sets up the credentials in the elasticsearch config.
+// It returns the updated config.
+func setupCredentailsUsingCredentialsProvider(ctx context.Context, esConfig *elasticsearch.Config, key string, mechanism string, forceRefresh bool) error {
 	if key == "" {
-		return nil, errCredentialProviderKeyNotSet
+		return errCredentialProviderKeyNotSet
 	}
 	if mechanism == "" {
-		return nil, errCredentialProviderMechanismNotSet
+		return errCredentialProviderMechanismNotSet
 	}
 	if mechanism != "api-key" && mechanism != "service-token" {
-		return nil, errCredentialProviderMechanismInvalid
+		return errCredentialProviderMechanismInvalid
 	}
 
 	credential, err := credentials.AcquireCredentials(ctx, key, forceRefresh)
 	if err != nil {
-		return nil, err
+		return err
 	}
 
-	esConfig := elasticsearch.Config{}
 	if mechanism == "api-key" {
 		esConfig.APIKey = credential
 	} else {
 		esConfig.ServiceToken = credential
 	}
-	return &esConfig, nil
+	return nil
 }
 
 func GetDefaultResultSize() int {
@@ -116,3 +120,23 @@ func GetDefaultResultSize() int {
 
 	return size
 }
+
+// getBaseConfig returns a new elasticsearch client with only the address set.
+// This function should be used to setup the config with properties
+// that will be common across all configs (credentials provieder based configs or env based configs).
+func getBaseConfig() (*elasticsearch.Config, error) {
+	esConfig := elasticsearch.Config{}
+
+	// Read the address
+	address := os.Getenv(elasticsearchUrl)
+	if address == "" {
+		return nil, errElasticsearchUrlNotSet
+	}
+
+	// Split the address by comma
+	addresses := make([]string, 0)
+	addresses = append(addresses, strings.Split(address, ",")...)
+	esConfig.Addresses = addresses
+
+	return &esConfig, nil
+}

elasticsearch/config_test.go

@@ -4,26 +4,31 @@ import (
 	"context"
 	"errors"
 	"testing"
+
+	"github.com/elastic/go-elasticsearch/v8"
 )
 
-func TestUseCredentailsProvider(t *testing.T) {
+func TestSetupCredentailsUsingCredentialsProvider(t *testing.T) {
 	t.Run("should return error if key is not set", func(t *testing.T) {
-		_, err := useCredentialsProvider(context.Background(), "", "", false)
+		esConfig := elasticsearch.Config{}
+		err := setupCredentailsUsingCredentialsProvider(context.Background(), &esConfig, "", "", false)
 		if !errors.Is(err, errCredentialProviderKeyNotSet) {
 			t.Errorf("expected error to be errCredentialProviderKeyNotSet, got %v", err)
 		}
 	})
 
 	t.Run("key is set", func(t *testing.T) {
 		t.Run("should return error if mechanism is not set", func(t *testing.T) {
-			_, err := useCredentialsProvider(context.Background(), "key", "", false)
+			esConfig := elasticsearch.Config{}
+			err := setupCredentailsUsingCredentialsProvider(context.Background(), &esConfig, "key", "", false)
 			if !errors.Is(err, errCredentialProviderMechanismNotSet) {
 				t.Errorf("expected error to be errCredentialProviderMechanismNotSet, got %v", err)
 			}
 		})
 
 		t.Run("should return error if mechanism is invalid", func(t *testing.T) {
-			_, err := useCredentialsProvider(context.Background(), "key", "invalid", false)
+			esConfig := elasticsearch.Config{}
+			err := setupCredentailsUsingCredentialsProvider(context.Background(), &esConfig, "key", "invalid", false)
 			if !errors.Is(err, errCredentialProviderMechanismInvalid) {
 				t.Errorf("expected error to be errCredentialProviderMechanismInvalid, got %v", err)
 			}