Skip Alter ADD CONSTRAINT when changing the table schema (#39)

* skip unsupported table definitions

* improve test

* add test

* cast only if `table.Op == rel.SchemaAlter`

go.mod

@@ -4,7 +4,7 @@ go 1.16
 
 require (
 	github.com/go-rel/rel v0.38.0
-	github.com/go-rel/sql v0.12.0
+	github.com/go-rel/sql v0.12.1-0.20221010124958-ac6e8b8d87f0
 	github.com/mattn/go-sqlite3 v1.14.15
 	github.com/stretchr/testify v1.8.0
 )

go.sum

@@ -8,6 +8,8 @@ github.com/go-rel/rel v0.38.0 h1:XooFDMrzHNaZSNvH1ZrEpcn/7TvPz37z1kA66N3Ahjo=
 github.com/go-rel/rel v0.38.0/go.mod h1:Zq18pQqXZbDh2JBCo29jgt+y90nZWkUvI+W9Ls29ans=
 github.com/go-rel/sql v0.12.0 h1:1iIm2JgUr854TjN2C2403A9nZKH1RwbMJp09SQC4HO8=
 github.com/go-rel/sql v0.12.0/go.mod h1:Usxy37iCTA5aIqoJGekV4ATdCUOK5w2FiR00/VvvLJQ=
+github.com/go-rel/sql v0.12.1-0.20221010124958-ac6e8b8d87f0 h1:C6KJcSVP+f8ZDgDgVJiA1/2OxkuViNB6z8TpDKaBMxI=
+github.com/go-rel/sql v0.12.1-0.20221010124958-ac6e8b8d87f0/go.mod h1:LJHx6rhOHC4PIFFzqoR6RA7QYJ2jCOrW7spUmJq9Raw=
 github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/golang/protobuf v1.4.0-rc.1/go.mod h1:ceaxUfeHdC40wWswd/P6IGgMaK3YpKi5j83Wpe3EHw8=
 github.com/golang/protobuf v1.4.0-rc.1.0.20200221234624-67d41d38c208/go.mod h1:xKAWHe0F5eneWXFV3EuXVDTCmh+JuBKY0li0aMyXATA=

sqlite3.go

@@ -14,6 +14,7 @@ package sqlite3
 
 import (
 	db "database/sql"
+	"log"
 	"strings"
 
 	"github.com/go-rel/rel"
@@ -34,7 +35,7 @@ func New(database *db.DB) rel.Adapter {
 		deleteBuilder     = builder.Delete{BufferFactory: bufferFactory, Query: queryBuilder, Filter: filterBuilder}
 		ddlBufferFactory  = builder.BufferFactory{InlineValues: true, BoolTrueValue: "1", BoolFalseValue: "0", Quoter: builder.Quote{IDPrefix: "\"", IDSuffix: "\"", IDSuffixEscapeChar: "\"", ValueQuote: "'", ValueQuoteEscapeChar: "'"}}
 		ddlQueryBuilder   = builder.Query{BufferFactory: ddlBufferFactory, Filter: filterBuilder}
-		tableBuilder      = builder.Table{BufferFactory: ddlBufferFactory, ColumnMapper: columnMapper}
+		tableBuilder      = builder.Table{BufferFactory: ddlBufferFactory, ColumnMapper: columnMapper, DefinitionFilter: definitionFilter}
 		indexBuilder      = builder.Index{BufferFactory: ddlBufferFactory, Query: ddlQueryBuilder, Filter: filterBuilder, SupportFilter: true}
 	)
 
@@ -119,3 +120,18 @@ func columnMapper(column *rel.Column) (string, int, int) {
 
 	return typ, m, n
 }
+
+func definitionFilter(table rel.Table, def rel.TableDefinition) bool {
+	if table.Op == rel.SchemaAlter {
+		// https://www.sqlite.org/omitted.html
+		// > Only the RENAME TABLE, ADD COLUMN, RENAME COLUMN, and DROP COLUMN variants of the ALTER TABLE command are supported.
+		_, ok := def.(rel.Key)
+		if ok {
+			log.Print("[REL] SQLite3 adapter does not support adding keys when modifying tables")
+
+			return false
+		}
+	}
+
+	return true
+}

sqlite3_test.go

@@ -6,6 +6,7 @@ import (
 	"testing"
 
 	"github.com/go-rel/rel"
+	"github.com/go-rel/sql"
 	"github.com/go-rel/sql/specs"
 	_ "github.com/mattn/go-sqlite3"
 	"github.com/stretchr/testify/assert"
@@ -123,3 +124,45 @@ func TestAdapter_Exec_error(t *testing.T) {
 	_, _, err = adapter.Exec(ctx, "error", nil)
 	assert.NotNil(t, err)
 }
+
+func TestAdapter_TableBuilder(t *testing.T) {
+	adapter, err := Open(dsn())
+	assert.Nil(t, err)
+	defer adapter.Close()
+
+	tests := []struct {
+		result string
+		table  rel.Table
+	}{
+		{
+			result: `ALTER TABLE "columns" ADD COLUMN "verified" BOOL;ALTER TABLE "columns" RENAME COLUMN "string" TO "name";ALTER TABLE "columns" ;ALTER TABLE "columns" DROP COLUMN "blob";`,
+			table: rel.Table{
+				Op:   rel.SchemaAlter,
+				Name: "columns",
+				Definitions: []rel.TableDefinition{
+					rel.Column{Name: "verified", Type: rel.Bool, Op: rel.SchemaCreate},
+					rel.Column{Name: "string", Rename: "name", Op: rel.SchemaRename},
+					rel.Column{Name: "bool", Type: rel.Int, Op: rel.SchemaAlter},
+					rel.Column{Name: "blob", Op: rel.SchemaDrop},
+
+					// unsupported and will be skipped
+					rel.Key{Op: rel.SchemaCreate, Columns: []string{"user_id"}, Type: rel.ForeignKey, Reference: rel.ForeignKeyReference{Table: "products", Columns: []string{"id", "name"}}},
+				},
+			},
+		},
+		{
+			result: `ALTER TABLE "table" RENAME TO "table1";`,
+			table: rel.Table{
+				Op:     rel.SchemaRename,
+				Name:   "table",
+				Rename: "table1",
+			},
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.result, func(t *testing.T) {
+			assert.Equal(t, test.result, adapter.(*sql.SQL).TableBuilder.Build(test.table))
+		})
+	}
+}