MCP Toolbox for Databases

// Copyright 2025 Google LLC // // 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 elasticsearchesql import ( "bytes" "context" "encoding/json" "fmt" "time" "github.com/elastic/go-elasticsearch/v9/esapi" "github.com/googleapis/genai-toolbox/internal/util" "github.com/googleapis/genai-toolbox/internal/util/parameters" "github.com/goccy/go-yaml" "github.com/googleapis/genai-toolbox/internal/sources" es "github.com/googleapis/genai-toolbox/internal/sources/elasticsearch" "github.com/googleapis/genai-toolbox/internal/tools" ) const kind string = "elasticsearch-esql" func init() { if !tools.Register(kind, newConfig) { panic(fmt.Sprintf("tool kind %q already registered", kind)) } } type compatibleSource interface { ElasticsearchClient() es.EsClient } type Config struct { Name string `yaml:"name" validate:"required"` Kind string `yaml:"kind" validate:"required"` Source string `yaml:"source" validate:"required"` Description string `yaml:"description" validate:"required"` AuthRequired []string `yaml:"authRequired" validate:"required"` Query string `yaml:"query"` Format string `yaml:"format"` Timeout int `yaml:"timeout"` Parameters parameters.Parameters `yaml:"parameters"` } var _ tools.ToolConfig = Config{} func (c Config) ToolConfigKind() string { return kind } func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (tools.ToolConfig, error) { actual := Config{Name: name} if err := decoder.DecodeContext(ctx, &actual); err != nil { return nil, err } return actual, nil } type Tool struct { Config manifest tools.Manifest mcpManifest tools.McpManifest } var _ tools.Tool = Tool{} func (c Config) Initialize(srcs map[string]sources.Source) (tools.Tool, error) { mcpManifest := tools.GetMcpManifest(c.Name, c.Description, c.AuthRequired, c.Parameters, nil) return Tool{ Config: c, manifest: tools.Manifest{Description: c.Description, Parameters: c.Parameters.Manifest(), AuthRequired: c.AuthRequired}, mcpManifest: mcpManifest, }, nil } func (t Tool) ToConfig() tools.ToolConfig { return t.Config } type esqlColumn struct { Name string `json:"name"` Type string `json:"type"` } type esqlResult struct { Columns []esqlColumn `json:"columns"` Values [][]any `json:"values"` } func (t Tool) Invoke(ctx context.Context, resourceMgr tools.SourceProvider, params parameters.ParamValues, accessToken tools.AccessToken) (any, error) { source, err := tools.GetCompatibleSource[compatibleSource](resourceMgr, t.Source, t.Name, t.Kind) if err != nil { return nil, err } var cancel context.CancelFunc if t.Timeout > 0 { ctx, cancel = context.WithTimeout(ctx, time.Duration(t.Timeout)*time.Second) defer cancel() } else { ctx, cancel = context.WithTimeout(ctx, time.Minute) defer cancel() } bodyStruct := struct { Query string `json:"query"` Params []map[string]any `json:"params,omitempty"` }{ Query: t.Query, Params: make([]map[string]any, 0, len(params)), } paramMap := params.AsMap() // If a query is provided in the params and not already set in the tool, use it. if query, ok := paramMap["query"]; ok { if str, ok := query.(string); ok && bodyStruct.Query == "" { bodyStruct.Query = str } // Drop the query param if not a string or if the tool already has a query. delete(paramMap, "query") } for _, param := range t.Parameters { if param.GetType() == "array" { return nil, fmt.Errorf("array parameters are not supported yet") } bodyStruct.Params = append(bodyStruct.Params, map[string]any{param.GetName(): paramMap[param.GetName()]}) } body, err := json.Marshal(bodyStruct) if err != nil { return nil, fmt.Errorf("failed to marshal query body: %w", err) } res, err := esapi.EsqlQueryRequest{ Body: bytes.NewReader(body), Format: t.Format, FilterPath: []string{"columns", "values"}, Instrument: source.ElasticsearchClient().InstrumentationEnabled(), }.Do(ctx, source.ElasticsearchClient()) if err != nil { return nil, err } defer res.Body.Close() if res.IsError() { // Try to extract error message from response var esErr json.RawMessage err = util.DecodeJSON(res.Body, &esErr) if err != nil { return nil, fmt.Errorf("elasticsearch error: status %s", res.Status()) } return esErr, nil } var result esqlResult err = util.DecodeJSON(res.Body, &result) if err != nil { return nil, fmt.Errorf("failed to decode response body: %w", err) } output := t.esqlToMap(result) return output, nil } // esqlToMap converts the esqlResult to a slice of maps. func (t Tool) esqlToMap(result esqlResult) []map[string]any { output := make([]map[string]any, 0, len(result.Values)) for _, value := range result.Values { row := make(map[string]any) if value == nil { output = append(output, row) continue } for i, col := range result.Columns { if i < len(value) { row[col.Name] = value[i] } else { row[col.Name] = nil } } output = append(output, row) } return output } func (t Tool) ParseParams(data map[string]any, claims map[string]map[string]any) (parameters.ParamValues, error) { return parameters.ParseParams(t.Parameters, data, claims) } func (t Tool) Manifest() tools.Manifest { return t.manifest } func (t Tool) McpManifest() tools.McpManifest { return t.mcpManifest } func (t Tool) Authorized(verifiedAuthServices []string) bool { return tools.IsAuthorized(t.AuthRequired, verifiedAuthServices) } func (t Tool) RequiresClientAuthorization(resourceMgr tools.SourceProvider) (bool, error) { return false, nil } func (t Tool) GetAuthTokenHeaderName(resourceMgr tools.SourceProvider) (string, error) { return "Authorization", nil }