feat: opensearch客户端初始化 feat: 索引模板接口 ai: 开发准则 chore: TDD流水线脚本

operations/index/template.go

@@ -0,0 +1,217 @@
+// Package index provides index-level operations for OpenSearch.
+package index
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"os"
+
+	"es-demo/client"
+
+	"github.com/opensearch-project/opensearch-go/v2/opensearchapi"
+)
+
+var (
+	// ErrInvalidTemplate is returned when the template configuration is invalid.
+	ErrInvalidTemplate = errors.New("invalid template configuration")
+
+	// ErrTemplateNotFound is returned when the specified template does not exist.
+	ErrTemplateNotFound = errors.New("template not found")
+)
+
+// Template represents an OpenSearch index template.
+type Template struct {
+	// IndexPatterns defines the index patterns this template applies to.
+	IndexPatterns []string `json:"index_patterns"`
+
+	// Settings contains index settings like number of shards and replicas.
+	Settings map[string]any `json:"settings,omitempty"`
+
+	// Mappings defines the field mappings for the index.
+	Mappings map[string]any `json:"mappings,omitempty"`
+
+	// Aliases defines index aliases.
+	Aliases map[string]any `json:"aliases,omitempty"`
+
+	// Priority determines template precedence when multiple templates match.
+	Priority int `json:"priority,omitempty"`
+
+	// Version is used for external version management.
+	Version int `json:"version,omitempty"`
+}
+
+// TemplateResponse represents the response when getting a template.
+type TemplateResponse struct {
+	IndexTemplates []struct {
+		Name          string   `json:"name"`
+		IndexTemplate Template `json:"index_template"`
+	} `json:"index_templates"`
+}
+
+// PutTemplate creates or updates an index template.
+func PutTemplate(ctx context.Context, c *client.Client, name string, template *Template) error {
+	if err := validateTemplate(template); err != nil {
+		return err
+	}
+
+	if name == "" {
+		return fmt.Errorf("%w: template name is required", ErrInvalidTemplate)
+	}
+
+	body, err := json.Marshal(template)
+	if err != nil {
+		return fmt.Errorf("failed to marshal template: %w", err)
+	}
+
+	req := opensearchapi.IndicesPutIndexTemplateRequest{
+		Name: name,
+		Body: bytes.NewReader(body),
+	}
+
+	res, err := req.Do(ctx, c.GetClient())
+	if err != nil {
+		return fmt.Errorf("failed to execute put template request: %w", err)
+	}
+	defer func() {
+		if closeErr := res.Body.Close(); closeErr != nil {
+			fmt.Fprintf(os.Stderr, "warning: failed to close response body: %v\n", closeErr)
+		}
+	}()
+
+	if res.IsError() {
+		bodyBytes, _ := io.ReadAll(res.Body)
+		return fmt.Errorf("put template failed with status %s: %s", res.Status(), string(bodyBytes))
+	}
+
+	return nil
+}
+
+// GetTemplate retrieves an index template by name.
+func GetTemplate(ctx context.Context, c *client.Client, name string) (*Template, error) {
+	if name == "" {
+		return nil, fmt.Errorf("%w: template name is required", ErrInvalidTemplate)
+	}
+
+	req := opensearchapi.IndicesGetIndexTemplateRequest{
+		Name: []string{name},
+	}
+
+	res, err := req.Do(ctx, c.GetClient())
+	if err != nil {
+		return nil, fmt.Errorf("failed to execute get template request: %w", err)
+	}
+	defer func() {
+		if closeErr := res.Body.Close(); closeErr != nil {
+			fmt.Fprintf(os.Stderr, "warning: failed to close response body: %v\n", closeErr)
+		}
+	}()
+
+	if res.IsError() {
+		if res.StatusCode == 404 {
+			return nil, ErrTemplateNotFound
+		}
+		bodyBytes, _ := io.ReadAll(res.Body)
+		return nil, fmt.Errorf("get template failed with status %s: %s", res.Status(), string(bodyBytes))
+	}
+
+	var response TemplateResponse
+	if err := json.NewDecoder(res.Body).Decode(&response); err != nil {
+		return nil, fmt.Errorf("failed to decode template response: %w", err)
+	}
+
+	if len(response.IndexTemplates) == 0 {
+		return nil, ErrTemplateNotFound
+	}
+
+	return &response.IndexTemplates[0].IndexTemplate, nil
+}
+
+// DeleteTemplate deletes an index template.
+func DeleteTemplate(ctx context.Context, c *client.Client, name string) error {
+	if name == "" {
+		return fmt.Errorf("%w: template name is required", ErrInvalidTemplate)
+	}
+
+	req := opensearchapi.IndicesDeleteIndexTemplateRequest{
+		Name: name,
+	}
+
+	res, err := req.Do(ctx, c.GetClient())
+	if err != nil {
+		return fmt.Errorf("failed to execute delete template request: %w", err)
+	}
+	defer func() {
+		if closeErr := res.Body.Close(); closeErr != nil {
+			fmt.Fprintf(os.Stderr, "warning: failed to close response body: %v\n", closeErr)
+		}
+	}()
+
+	if res.IsError() {
+		if res.StatusCode == 404 {
+			return ErrTemplateNotFound
+		}
+		bodyBytes, _ := io.ReadAll(res.Body)
+		return fmt.Errorf("delete template failed with status %s: %s", res.Status(), string(bodyBytes))
+	}
+
+	return nil
+}
+
+// ListTemplates retrieves all index templates or templates matching a pattern.
+func ListTemplates(ctx context.Context, c *client.Client, names ...string) (map[string]*Template, error) {
+	var nameList []string
+	if len(names) > 0 {
+		nameList = names
+	}
+
+	req := opensearchapi.IndicesGetIndexTemplateRequest{
+		Name: nameList,
+	}
+
+	res, err := req.Do(ctx, c.GetClient())
+	if err != nil {
+		return nil, fmt.Errorf("failed to execute list templates request: %w", err)
+	}
+	defer func() {
+		if closeErr := res.Body.Close(); closeErr != nil {
+			fmt.Fprintf(os.Stderr, "warning: failed to close response body: %v\n", closeErr)
+		}
+	}()
+
+	if res.IsError() {
+		if res.StatusCode == 404 {
+			return make(map[string]*Template), nil
+		}
+		bodyBytes, _ := io.ReadAll(res.Body)
+		return nil, fmt.Errorf("list templates failed with status %s: %s", res.Status(), string(bodyBytes))
+	}
+
+	var response TemplateResponse
+	if err := json.NewDecoder(res.Body).Decode(&response); err != nil {
+		return nil, fmt.Errorf("failed to decode templates response: %w", err)
+	}
+
+	templates := make(map[string]*Template)
+	for _, item := range response.IndexTemplates {
+		templates[item.Name] = &item.IndexTemplate
+	}
+
+	return templates, nil
+}
+
+// validateTemplate validates the template configuration.
+func validateTemplate(template *Template) error {
+	if template == nil {
+		return fmt.Errorf("%w: template cannot be nil", ErrInvalidTemplate)
+	}
+
+	if len(template.IndexPatterns) == 0 {
+		return fmt.Errorf("%w: index patterns are required", ErrInvalidTemplate)
+	}
+
+	return nil
+}