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 postgreslistsequences import ( "context" "fmt" yaml "github.com/goccy/go-yaml" "github.com/googleapis/genai-toolbox/internal/sources" "github.com/googleapis/genai-toolbox/internal/tools" "github.com/googleapis/genai-toolbox/internal/util/parameters" "github.com/jackc/pgx/v5/pgxpool" ) const kind string = "postgres-list-sequences" const listSequencesStatement = ` SELECT sequencename as sequence_name, schemaname as schema_name, sequenceowner as sequence_owner, data_type, start_value, min_value, max_value, increment_by, last_value FROM pg_sequences WHERE ($1::text IS NULL OR schemaname LIKE '%' || $1 || '%') AND ($2::text IS NULL OR sequencename LIKE '%' || $2 || '%') ORDER BY schema_name, sequence_name LIMIT COALESCE($3::int, 50); ` func init() { if !tools.Register(kind, newConfig) { panic(fmt.Sprintf("tool kind %q already registered", 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 compatibleSource interface { PostgresPool() *pgxpool.Pool } 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"` AuthRequired []string `yaml:"authRequired"` } // validate interface var _ tools.ToolConfig = Config{} func (cfg Config) ToolConfigKind() string { return kind } func (cfg Config) Initialize(srcs map[string]sources.Source) (tools.Tool, error) { allParameters := parameters.Parameters{ parameters.NewStringParameterWithDefault("schema_name", "", "Optional: A specific schema name pattern to search for."), parameters.NewStringParameterWithDefault("sequence_name", "", "Optional: A specific sequence name pattern to search for."), parameters.NewIntParameterWithDefault("limit", 50, "Optional: The maximum number of rows to return. Default is 50"), } if cfg.Description == "" { cfg.Description = "Lists sequences in the database. Returns sequence name, schema name, sequence owner, data type of the sequence, starting value, minimum value, maximum value of the sequence, the value by which the sequence is incremented, and the last value generated by the sequence in the current session" } mcpManifest := tools.GetMcpManifest(cfg.Name, cfg.Description, cfg.AuthRequired, allParameters, nil) // finish tool setup return Tool{ Config: cfg, allParams: allParameters, manifest: tools.Manifest{ Description: cfg.Description, Parameters: allParameters.Manifest(), AuthRequired: cfg.AuthRequired, }, mcpManifest: mcpManifest, }, nil } // validate interface var _ tools.Tool = Tool{} type Tool struct { Config allParams parameters.Parameters `yaml:"allParams"` manifest tools.Manifest mcpManifest tools.McpManifest } func (t Tool) ToConfig() tools.ToolConfig { return t.Config } 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 } paramsMap := params.AsMap() newParams, err := parameters.GetParams(t.allParams, paramsMap) if err != nil { return nil, fmt.Errorf("unable to extract standard params %w", err) } sliceParams := newParams.AsSlice() results, err := source.PostgresPool().Query(ctx, listSequencesStatement, sliceParams...) if err != nil { return nil, fmt.Errorf("unable to execute query: %w", err) } defer results.Close() fields := results.FieldDescriptions() var out []map[string]any for results.Next() { values, err := results.Values() if err != nil { return nil, fmt.Errorf("unable to parse row: %w", err) } rowMap := make(map[string]any) for i, field := range fields { rowMap[string(field.Name)] = values[i] } out = append(out, rowMap) } // this will catch actual query execution errors if err := results.Err(); err != nil { return nil, fmt.Errorf("unable to execute query: %w", err) } return out, nil } func (t Tool) ParseParams(data map[string]any, claims map[string]map[string]any) (parameters.ParamValues, error) { return parameters.ParseParams(t.allParams, 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 }