Allow for multistatement migrations in Neo4j (golang-migrate#328)

* allow for multistatement migrations

* multi statement option

* parse bool and package const

* default false multi, change package var to byte[]

database/cassandra/README.md

@@ -3,7 +3,7 @@
 * Drop command will not work on Cassandra 2.X because it rely on
 system_schema table which comes with 3.X
 * Other commands should work properly but are **not tested**
-* The Cassandra driver (gocql) does not natively support executing multipe statements in a single query. To allow for multiple statements in a single migration, you can use the `x-multi-statement` param. There are two important caveats:
+* The Cassandra driver (gocql) does not natively support executing multiple statements in a single query. To allow for multiple statements in a single migration, you can use the `x-multi-statement` param. There are two important caveats:
   * This mode splits the migration text into separately-executed statements by a semi-colon `;`. Thus `x-multi-statement` cannot be used when a statement in the migration contains a string with a semi-colon.
   * The queries are not executed in any sort of transaction/batch, meaning you are responsible for fixing partial migrations.
 

database/neo4j/README.md

@@ -1,9 +1,14 @@
 # neo4j
+The Neo4j driver (bolt) does not natively support executing multiple statements in a single query. To allow for multiple statements in a single migration, you can use the `x-multi-statement` param. 
+This mode splits the migration text into separately-executed statements by a semi-colon `;`. Thus `x-multi-statement` cannot be used when a statement in the migration contains a string with a semi-colon.
+The queries **should** run in a single transaction, so partial migrations should not be a concern, but this is untested.
+
 
 `neo4j://user:password@host:port/`
 
 | URL Query  | WithInstance Config | Description |
 |------------|---------------------|-------------|
+| `x-multi-statement` | `MultiStatement` | Enable multiple statements to be ran in a single migration (See note above) |
 | `user` | Contained within `AuthConfig` | The user to sign in as |
 | `password` | Contained within `AuthConfig` | The user's password |
 | `host` | | The host to connect to. Values that start with / are for unix domain sockets. (default is localhost) |

database/neo4j/examples/migrations/1578421726_multistatement_test.up.cypher

@@ -0,0 +1,3 @@
+CREATE (:Movie {name: "Hollow Man"});
+CREATE (:Movie {name: "Mystic River"});
+;;;

database/neo4j/neo4j.go

@@ -2,14 +2,16 @@ package neo4j
 
 import (
 	"C" // import C so that we can't compile with CGO_ENABLED=0
+	"bytes"
 	"fmt"
-	"github.com/hashicorp/go-multierror"
 	"io"
 	"io/ioutil"
 	neturl "net/url"
+	"strconv"
 	"sync/atomic"
 
 	"github.com/golang-migrate/migrate/v4/database"
+	"github.com/hashicorp/go-multierror"
 	"github.com/neo4j/neo4j-go-driver/neo4j"
 )
 
@@ -18,7 +20,9 @@ func init() {
 	database.Register("neo4j", &db)
 }
 
-var DefaultMigrationsLabel = "SchemaMigration"
+const DefaultMigrationsLabel = "SchemaMigration"
+
+var StatementSeparator = []byte(";")
 
 var (
 	ErrNilConfig = fmt.Errorf("no config")
@@ -28,6 +32,7 @@ type Config struct {
 	AuthToken       neo4j.AuthToken
 	URL             string // if using WithInstance, don't provide auth in the URL, it will be ignored
 	MigrationsLabel string
+	MultiStatement  bool
 }
 
 type Neo4j struct {
@@ -69,11 +74,21 @@ func (n *Neo4j) Open(url string) (database.Driver, error) {
 	authToken := neo4j.BasicAuth(uri.User.Username(), password, "")
 	uri.User = nil
 	uri.Scheme = "bolt"
+	msQuery := uri.Query().Get("x-multi-statement")
+	multi := false
+	if msQuery != "" {
+		multi, err = strconv.ParseBool(uri.Query().Get("x-multi-statement"))
+		if err != nil {
+			return nil, err
+		}
+	}
+	uri.RawQuery = ""
 
 	return WithInstance(&Config{
 		URL:             uri.String(),
 		AuthToken:       authToken,
 		MigrationsLabel: DefaultMigrationsLabel,
+		MultiStatement:  multi,
 	})
 }
 
@@ -113,9 +128,30 @@ func (n *Neo4j) Run(migration io.Reader) (err error) {
 		}
 	}()
 
-	if _, err := neo4j.Collect(session.Run(string(body[:]), nil)); err != nil {
-		return err
+	if n.config.MultiStatement {
+		statements := bytes.Split(body, StatementSeparator)
+		_, err = session.WriteTransaction(func(transaction neo4j.Transaction) (interface{}, error) {
+			for _, stmt := range statements {
+				trimStmt := bytes.TrimSpace(stmt)
+				if len(trimStmt) == 0 {
+					continue
+				}
+				result, err := transaction.Run(string(trimStmt[:]), nil)
+				if _, err := neo4j.Collect(result, err); err != nil {
+					return nil, err
+				}
+			}
+			return nil, nil
+		})
+		if err != nil {
+			return err
+		}
+	} else {
+		if _, err := neo4j.Collect(session.Run(string(body[:]), nil)); err != nil {
+			return err
+		}
 	}
+
 	return nil
 }
 

database/neo4j/neo4j_test.go

@@ -1,6 +1,7 @@
 package neo4j
 
 import (
+	"bytes"
 	"context"
 	"fmt"
 	"log"
@@ -88,7 +89,8 @@ func TestMigrate(t *testing.T) {
 		}
 
 		n := &Neo4j{}
-		d, err := n.Open(neoConnectionString(ip, port))
+		neoUrl := neoConnectionString(ip, port) + "/?x-multi-statement=true"
+		d, err := n.Open(neoUrl)
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -104,3 +106,28 @@ func TestMigrate(t *testing.T) {
 		dt.TestMigrate(t, m)
 	})
 }
+
+func TestMalformed(t *testing.T) {
+	dktesting.ParallelTest(t, specs, func(t *testing.T, c dktest.ContainerInfo) {
+		ip, port, err := c.Port(7687)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		n := &Neo4j{}
+		d, err := n.Open(neoConnectionString(ip, port))
+		if err != nil {
+			t.Fatal(err)
+		}
+		defer func() {
+			if err := d.Close(); err != nil {
+				t.Error(err)
+			}
+		}()
+
+		migration := bytes.NewReader([]byte("CREATE (a {qid: 1) RETURN a"))
+		if err := d.Run(migration); err == nil {
+			t.Fatal("expected failure for malformed migration")
+		}
+	})
+}

internal/cli/build_clickhouse.go

@@ -3,6 +3,6 @@
 package cli
 
 import (
-	_ "github.com/golang-migrate/migrate/v4/database/clickhouse"
 	_ "github.com/ClickHouse/clickhouse-go"
+	_ "github.com/golang-migrate/migrate/v4/database/clickhouse"
 )

internal/cli/build_neo4j.go

@@ -4,4 +4,4 @@ package cli
 
 import (
 	_ "github.com/golang-migrate/migrate/v4/database/neo4j"
-)
+)