MCP Toolbox for Databases

// Copyright 2024 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 spannersql import ( "context" "fmt" "strings" "cloud.google.com/go/spanner" 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" "google.golang.org/api/iterator" ) const kind string = "spanner-sql" 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 { SpannerClient() *spanner.Client DatabaseDialect() string } 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"` Statement string `yaml:"statement" validate:"required"` ReadOnly bool `yaml:"readOnly"` AuthRequired []string `yaml:"authRequired"` Parameters parameters.Parameters `yaml:"parameters"` TemplateParameters parameters.Parameters `yaml:"templateParameters"` } // 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, paramManifest, err := parameters.ProcessParameters(cfg.TemplateParameters, cfg.Parameters) if err != nil { return nil, err } mcpManifest := tools.GetMcpManifest(cfg.Name, cfg.Description, cfg.AuthRequired, allParameters, nil) // finish tool setup t := Tool{ Config: cfg, AllParams: allParameters, manifest: tools.Manifest{Description: cfg.Description, Parameters: paramManifest, AuthRequired: cfg.AuthRequired}, mcpManifest: mcpManifest, } return t, nil } // validate interface var _ tools.Tool = Tool{} type Tool struct { Config AllParams parameters.Parameters `yaml:"allParams"` manifest tools.Manifest mcpManifest tools.McpManifest } func getMapParams(params parameters.ParamValues, dialect string) (map[string]interface{}, error) { switch strings.ToLower(dialect) { case "googlesql": return params.AsMap(), nil case "postgresql": return params.AsMapByOrderedKeys(), nil default: return nil, fmt.Errorf("invalid dialect %s", dialect) } } // processRows iterates over the spanner.RowIterator and converts each row to a map[string]any. func processRows(iter *spanner.RowIterator) ([]any, error) { var out []any defer iter.Stop() for { row, err := iter.Next() if err == iterator.Done { break } if err != nil { return nil, fmt.Errorf("unable to parse row: %w", err) } vMap := make(map[string]any) cols := row.ColumnNames() for i, c := range cols { vMap[c] = row.ColumnValue(i) } out = append(out, vMap) } return out, nil } 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() newStatement, err := parameters.ResolveTemplateParams(t.TemplateParameters, t.Statement, paramsMap) if err != nil { return nil, fmt.Errorf("unable to extract template params %w", err) } newParams, err := parameters.GetParams(t.Parameters, paramsMap) if err != nil { return nil, fmt.Errorf("unable to extract standard params %w", err) } for i, p := range t.Parameters { name := p.GetName() value := newParams[i].Value // Spanner only accepts typed slices as input // This checks if the param is an array. // If yes, convert []any to typed slice (e.g []string, []int) switch arrayParam := p.(type) { case *parameters.ArrayParameter: arrayParamValue, ok := value.([]any) if !ok { return nil, fmt.Errorf("unable to convert parameter `%s` to []any %w", name, err) } itemType := arrayParam.GetItems().GetType() var err error value, err = parameters.ConvertAnySliceToTyped(arrayParamValue, itemType) if err != nil { return nil, fmt.Errorf("unable to convert parameter `%s` from []any to typed slice: %w", name, err) } } newParams[i] = parameters.ParamValue{Name: name, Value: value} } mapParams, err := getMapParams(newParams, source.DatabaseDialect()) if err != nil { return nil, fmt.Errorf("fail to get map params: %w", err) } var results []any var opErr error stmt := spanner.Statement{ SQL: newStatement, Params: mapParams, } if t.ReadOnly { iter := source.SpannerClient().Single().Query(ctx, stmt) results, opErr = processRows(iter) } else { _, opErr = source.SpannerClient().ReadWriteTransaction(ctx, func(ctx context.Context, txn *spanner.ReadWriteTransaction) error { iter := txn.Query(ctx, stmt) results, err = processRows(iter) if err != nil { return err } return nil }) } if opErr != nil { return nil, fmt.Errorf("unable to execute client: %w", opErr) } return results, 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) ToConfig() tools.ToolConfig { return t.Config } func (t Tool) GetAuthTokenHeaderName(resourceMgr tools.SourceProvider) (string, error) { return "Authorization", nil }