feat: add Postgres source and tool

internal/sources/postgres.go

@@ -0,0 +1,79 @@
+// 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 sources
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/jackc/pgx/v5/pgxpool"
+)
+
+const PostgresKind string = "postgres"
+
+// validate interface
+var _ Config = PostgresConfig{}
+
+type PostgresConfig struct {
+	Name     string `yaml:"name"`
+	Kind     string `yaml:"kind"`
+	Host     string `yaml:"host"`
+	Port     string `yaml:"port"`
+	User     string `yaml:"user"`
+	Password string `yaml:"password"`
+	Database string `yaml:"database"`
+}
+
+func (r PostgresConfig) sourceKind() string {
+	return PostgresKind
+}
+
+func (r PostgresConfig) Initialize() (Source, error) {
+	pool, err := initPostgresConnectionPool(r.Host, r.Port, r.User, r.Password, r.Database)
+	if err != nil {
+		return nil, fmt.Errorf("Unable to create pool: %w", err)
+	}
+
+	err = pool.Ping(context.Background())
+	if err != nil {
+		return nil, fmt.Errorf("Unable to connect successfully: %w", err)
+	}
+
+	s := PostgresSource{
+		Name: r.Name,
+		Kind: PostgresKind,
+		Pool: pool,
+	}
+	return s, nil
+}
+
+var _ Source = PostgresSource{}
+
+type PostgresSource struct {
+	Name string `yaml:"name"`
+	Kind string `yaml:"kind"`
+	Pool *pgxpool.Pool
+}
+
+func initPostgresConnectionPool(host, port, user, pass, dbname string) (*pgxpool.Pool, error) {
+    // urlExample := "postgres:dd//username:password@localhost:5432/database_name"
+	i := fmt.Sprintf("postgres://%s:%s@%s:%s/%s", user, pass, host, port, dbname)
+    pool, err := pgxpool.New(context.Background(), i)
+	if err != nil {
+		return nil, fmt.Errorf("Unable to create connection pool: %w", err)
+	}
+
+	return pool, nil
+}

internal/sources/postgres_test.go

@@ -0,0 +1,69 @@
+// 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 sources_test
+
+import (
+	"testing"
+
+	"github.com/google/go-cmp/cmp"
+	"github.com/googleapis/genai-toolbox/internal/sources"
+	"github.com/googleapis/genai-toolbox/internal/testutils"
+	"gopkg.in/yaml.v3"
+)
+
+func TestParseFromYamlPostgres(t *testing.T) {
+	tcs := []struct {
+		desc string
+		in   string
+		want sources.Configs
+	}{
+		{
+			desc: "basic example",
+			in: `
+			sources:
+				my-pg-instance:
+					kind: postgres
+					host: my-host
+					port: 0000
+					database: my_db
+			`,
+			want: sources.Configs{
+				"my-pg-instance": sources.PostgresConfig{
+					Name:     "my-pg-instance",
+					Kind:     sources.PostgresKind,
+					Host:  "my-host",
+					Port:   "0000",
+					Database: "my_db",
+				},
+			},
+		},
+	}
+	for _, tc := range tcs {
+		t.Run(tc.desc, func(t *testing.T) {
+			got := struct {
+				Sources sources.Configs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
+			if err != nil {
+				t.Fatalf("unable to unmarshal: %s", err)
+			}
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
+			}
+		})
+	}
+
+}

internal/sources/sources.go

@@ -54,6 +54,12 @@ func (c *Configs) UnmarshalYAML(node *yaml.Node) error {
 				return fmt.Errorf("unable to parse as %q: %w", k.Kind, err)
 			}
 			(*c)[name] = actual
+		case PostgresKind:
+			actual := PostgresConfig{Name: name}
+			if err := n.Decode(&actual); err != nil {
+				return fmt.Errorf("unable to parse as %q: %w", k.Kind, err)
+			}
+			(*c)[name] = actual
 		default:
 			return fmt.Errorf("%q is not a valid kind of data source", k.Kind)
 		}

internal/tools/postgres.go

@@ -0,0 +1,105 @@
+// 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 tools
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	"github.com/googleapis/genai-toolbox/internal/sources"
+)
+
+const PostgresSQLGenericKind string = "postgres-generic"
+
+// validate interface
+var _ Config = PostgresGenericConfig{}
+
+type PostgresGenericConfig struct {
+	Name        string      `yaml:"name"`
+	Kind        string      `yaml:"kind"`
+	Source      string      `yaml:"source"`
+	Description string      `yaml:"description"`
+	Statement   string      `yaml:"statement"`
+	Parameters  []Parameter `yaml:"parameters"`
+}
+
+func (cfg PostgresGenericConfig) toolKind() string {
+	return PostgresSQLGenericKind
+}
+
+func (cfg PostgresGenericConfig) Initialize(srcs map[string]sources.Source) (Tool, error) {
+	// verify source exists
+	rawS, ok := srcs[cfg.Source]
+	if !ok {
+		return nil, fmt.Errorf("no source named %q configured", cfg.Source)
+	}
+
+	// verify the source is the right kind
+	s, ok := rawS.(sources.PostgresSource)
+	if !ok {
+		return nil, fmt.Errorf("sources for %q tools must be of kind %q", PostgresSQLGenericKind, sources.PostgresKind)
+	}
+
+	// finish tool setup
+	t := PostgresGenericTool{
+		Name:       cfg.Name,
+		Kind:       PostgresSQLGenericKind,
+		Source:     s,
+		Statement:  cfg.Statement,
+		Parameters: cfg.Parameters,
+		manifest:   Manifest{cfg.Description, cfg.Parameters},
+	}
+	return t, nil
+}
+
+// validate interface
+var _ Tool = PostgresGenericTool{}
+
+type PostgresGenericTool struct {
+	Name       string `yaml:"name"`
+	Kind       string `yaml:"kind"`
+	Source     sources.PostgresSource
+	Statement  string
+	Parameters []Parameter `yaml:"parameters"`
+	manifest   Manifest
+}
+
+func (t PostgresGenericTool) Invoke(params []any) (string, error) {
+	fmt.Printf("Invoked tool %s\n", t.Name)
+	results, err := t.Source.Pool.Query(context.Background(), t.Statement, params...)
+	if err != nil {
+		return "", fmt.Errorf("unable to execute query: %w", err)
+	}
+
+	var out strings.Builder
+	for results.Next() {
+		v, err := results.Values()
+		if err != nil {
+			return "", fmt.Errorf("unable to parse row: %w", err)
+		}
+		out.WriteString(fmt.Sprintf("%s", v))
+	}
+
+	return fmt.Sprintf("Stub tool call for %q! Parameters parsed: %q \n Output: %s", t.Name, params, out.String()), nil
+}
+
+func (t PostgresGenericTool) ParseParams(data map[string]any) ([]any, error) {
+	return ParseParams(t.Parameters, data)
+}
+
+func (t PostgresGenericTool) Manifest() Manifest {
+	return t.manifest
+}

internal/tools/postgres_test.go

@@ -0,0 +1,81 @@
+// 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 tools_test
+
+import (
+	"testing"
+
+	"github.com/google/go-cmp/cmp"
+	"github.com/googleapis/genai-toolbox/internal/testutils"
+	"github.com/googleapis/genai-toolbox/internal/tools"
+	"gopkg.in/yaml.v3"
+)
+
+func TestParseFromYamlPostgres(t *testing.T) {
+	tcs := []struct {
+		desc string
+		in   string
+		want tools.Configs
+	}{
+		{
+			desc: "basic example",
+			in: `
+			tools:
+				example_tool:
+					kind: postgres-generic
+					source: my-pg-instance
+					description: some description
+					statement: |
+						SELECT * FROM SQL_STATEMENT;
+					parameters:
+						- name: country
+						  type: string
+						  description: some description
+			`,
+			want: tools.Configs{
+				"example_tool": tools.PostgresGenericConfig{
+					Name:        "example_tool",
+					Kind:        tools.PostgresSQLGenericKind,
+					Source:      "my-pg-instance",
+					Description: "some description",
+					Statement:   "SELECT * FROM SQL_STATEMENT;\n",
+					Parameters: []tools.Parameter{
+						{
+							Name:        "country",
+							Type:        "string",
+							Description: "some description",
+						},
+					},
+				},
+			},
+		},
+	}
+	for _, tc := range tcs {
+		t.Run(tc.desc, func(t *testing.T) {
+			got := struct {
+				Tools tools.Configs `yaml:"tools"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
+			if err != nil {
+				t.Fatalf("unable to unmarshal: %s", err)
+			}
+			if diff := cmp.Diff(tc.want, got.Tools); diff != "" {
+				t.Fatalf("incorrect parse: diff %v", diff)
+			}
+		})
+	}
+
+}

internal/tools/tools.go

@@ -55,6 +55,12 @@ func (c *Configs) UnmarshalYAML(node *yaml.Node) error {
 				return fmt.Errorf("unable to parse as %q: %w", k.Kind, err)
 			}
 			(*c)[name] = actual
+		case PostgresSQLGenericKind:
+			actual := PostgresGenericConfig{Name: name}
+			if err := n.Decode(&actual); err != nil {
+				return fmt.Errorf("unable to parse as %q: %w", k.Kind, err)
+			}
+			(*c)[name] = actual
 		default:
 			return fmt.Errorf("%q is not a valid kind of tool", k.Kind)
 		}