add: generate scoped search keys function (#142)

typesense/keys.go

@@ -2,13 +2,19 @@ package typesense
 
 import (
 	"context"
+	"crypto/hmac"
+	"crypto/sha256"
+	"encoding/base64"
+	"encoding/json"
+	"fmt"
 
 	"github.com/typesense/typesense-go/typesense/api"
 )
 
 type KeysInterface interface {
 	Create(key *api.ApiKeySchema) (*api.ApiKey, error)
 	Retrieve() ([]*api.ApiKey, error)
+	GenerateScopedSearchKey(searchKey string, params map[string]interface{}) (string, error)
 }
 
 type keys struct {
@@ -37,3 +43,17 @@ func (k *keys) Retrieve() ([]*api.ApiKey, error) {
 	}
 	return response.JSON200.Keys, nil
 }
+
+func (k *keys) GenerateScopedSearchKey(searchKey string, params map[string]interface{}) (string, error) {
+	paramsStr, err := json.Marshal(params)
+	if err != nil {
+		return "", err
+	}
+
+	mac := hmac.New(sha256.New, []byte(searchKey))
+	mac.Write(paramsStr)
+
+	digest := base64.StdEncoding.EncodeToString(mac.Sum(nil))
+	rawScopedKey := fmt.Sprintf("%s%s%s", digest, searchKey[0:4], paramsStr)
+	return base64.StdEncoding.EncodeToString([]byte(rawScopedKey)), nil
+}

typesense/keys_test.go

@@ -161,3 +161,16 @@ func TestKeysRetrieveOnHttpStatusErrorCodeReturnsError(t *testing.T) {
 	_, err := client.Keys().Retrieve()
 	assert.NotNil(t, err)
 }
+
+func TestKeysGenerateScopedSearchKey(t *testing.T) {
+	// setup example from the docs
+	searchKey := "RN23GFr1s6jQ9kgSNg2O7fYcAUXU7127"
+	scopedSearchKey := "SC9sT0hncHFwTHNFc3U3d3psRDZBUGNXQUViQUdDNmRHSmJFQnNnczJ4VT1STjIzeyJmaWx0ZXJfYnkiOiJjb21wYW55X2lkOjEyNCJ9"
+
+	scopedKey, err := (&keys{}).GenerateScopedSearchKey(searchKey, map[string]interface{}{
+		"filter_by": "company_id:124",
+	})
+
+	assert.NoError(t, err)
+	assert.Equal(t, scopedKey, scopedSearchKey)
+}