chore: import upstream snapshot with attribution

server/node/create_extension.go

@@ -0,0 +1,204 @@
+// Copyright 2025 Dolthub, Inc.
+//
+// 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 node
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	"github.com/cockroachdb/errors"
+	"github.com/dolthub/go-mysql-server/sql"
+	"github.com/dolthub/go-mysql-server/sql/plan"
+	vitess "github.com/dolthub/vitess/go/vt/sqlparser"
+
+	"github.com/dolthub/doltgresql/core"
+	"github.com/dolthub/doltgresql/core/extensions"
+	"github.com/dolthub/doltgresql/core/id"
+	"github.com/dolthub/doltgresql/postgres/parser/parser"
+	"github.com/dolthub/doltgresql/postgres/parser/sem/tree"
+	pgexprs "github.com/dolthub/doltgresql/server/expression"
+)
+
+// CreateExtension implements CREATE EXTENSION.
+type CreateExtension struct {
+	Name        string
+	IfNotExists bool
+	SchemaName  string
+	Version     string
+	Cascade     bool
+	Runner      pgexprs.StatementRunner
+}
+
+var _ sql.ExecSourceRel = (*CreateExtension)(nil)
+var _ sql.Expressioner = (*CreateExtension)(nil)
+var _ vitess.Injectable = (*CreateExtension)(nil)
+
+// NewCreateExtension returns a new *CreateExtension.
+func NewCreateExtension(name string, ifNotExists bool, schemaName string, version string, cascade bool) *CreateExtension {
+	return &CreateExtension{
+		Name:        name,
+		IfNotExists: ifNotExists,
+		SchemaName:  schemaName,
+		Version:     version,
+		Cascade:     cascade,
+	}
+}
+
+// Children implements the interface sql.ExecSourceRel.
+func (c *CreateExtension) Children() []sql.Node {
+	return nil
+}
+
+// Expressions implements the interface sql.Expressioner.
+func (c *CreateExtension) Expressions() []sql.Expression {
+	return []sql.Expression{c.Runner}
+}
+
+// IsReadOnly implements the interface sql.ExecSourceRel.
+func (c *CreateExtension) IsReadOnly() bool {
+	return false
+}
+
+// Resolved implements the interface sql.ExecSourceRel.
+func (c *CreateExtension) Resolved() bool {
+	return true
+}
+
+// RowIter implements the interface sql.ExecSourceRel.
+func (c *CreateExtension) RowIter(ctx *sql.Context, r sql.Row) (sql.RowIter, error) {
+	extCollection, err := core.GetExtensionsCollectionFromContext(ctx, "")
+	if err != nil {
+		return nil, err
+	}
+	if extCollection.HasLoadedExtension(ctx, id.NewExtension(c.Name)) {
+		if c.IfNotExists {
+			return sql.RowsToRowIter(), nil
+		}
+		return nil, errors.Errorf(`extension "%s" already exists`, c.Name)
+	}
+	ext, err := extensions.GetExtension(c.Name)
+	if err != nil {
+		return nil, err
+	}
+	// The returned files are in their proper order of execution, so we can iterate and execute
+	sqlFiles, err := ext.LoadSQLFiles()
+	if err != nil {
+		return nil, err
+	}
+	// save the current search_path
+	originalSchema, err := ctx.GetSessionVariable(ctx, "search_path")
+	if err != nil {
+		return nil, err
+	}
+
+	if c.SchemaName != "" {
+		defer func() {
+			_ = ctx.SetSessionVariable(ctx, "search_path", originalSchema)
+		}()
+
+		spErr := ctx.SetSessionVariable(ctx, "search_path", c.SchemaName)
+		if spErr != nil {
+			return nil, spErr
+		}
+	}
+
+	for _, sqlFile := range sqlFiles {
+		// Remove echo PSQL control statements
+		for {
+			echoStartIdx := strings.Index(sqlFile, `\echo`)
+			if echoStartIdx == -1 {
+				break
+			}
+			echoEndIdx := strings.Index(sqlFile[echoStartIdx:], "\n")
+			if echoEndIdx != -1 {
+				// Set the correct absolute position if there is a newline
+				echoEndIdx += echoStartIdx
+			} else {
+				// Set the position at the end of the file if there's no newline (comment appears before EOF)
+				echoEndIdx = len(sqlFile)
+			}
+			sqlFile = strings.Replace(sqlFile, sqlFile[echoStartIdx:echoEndIdx], "", 1)
+		}
+		statements, err := parser.Parse(sqlFile)
+		if err != nil {
+			return nil, err
+		}
+		for _, statement := range statements {
+			statementSQL := statement.SQL
+			if _, ok := statement.AST.(*tree.CreateFunction); ok {
+				statementSQL = strings.ReplaceAll(statementSQL, `'MODULE_PATHNAME'`, fmt.Sprintf(`'%s'`, c.Name))
+			}
+			_, err = sql.RunInterpreted(ctx, func(subCtx *sql.Context) ([]sql.Row, error) {
+				_, rowIter, _, err := c.Runner.Runner.QueryWithBindings(subCtx, statementSQL, nil, nil, nil)
+				if err != nil {
+					return nil, err
+				}
+				return sql.RowIterToRows(subCtx, rowIter)
+			})
+			if err != nil {
+				return nil, err
+			}
+		}
+	}
+
+	namespace := id.NullNamespace
+	if len(ext.Control.Schema) > 0 {
+		namespace = id.NewNamespace(ext.Control.Schema)
+	}
+	err = extCollection.AddLoadedExtension(ctx, extensions.Extension{
+		ExtName:       id.NewExtension(c.Name),
+		Namespace:     namespace,
+		Relocatable:   ext.Control.Relocatable,
+		LibIdentifier: extensions.CreateLibraryIdentifier(c.Name, ext.Control.DefaultVersion),
+	})
+	if err != nil {
+		return nil, err
+	}
+	return sql.RowsToRowIter(), nil
+}
+
+// Schema implements the interface sql.ExecSourceRel.
+func (c *CreateExtension) Schema(ctx *sql.Context) sql.Schema {
+	return nil
+}
+
+// String implements the interface sql.ExecSourceRel.
+func (c *CreateExtension) String() string {
+	return "CREATE EXTENSION"
+}
+
+// WithChildren implements the interface sql.ExecSourceRel.
+func (c *CreateExtension) WithChildren(ctx *sql.Context, children ...sql.Node) (sql.Node, error) {
+	return plan.NillaryWithChildren(c, children...)
+}
+
+// WithExpressions implements the interface sql.Expressioner.
+func (c *CreateExtension) WithExpressions(ctx *sql.Context, expressions ...sql.Expression) (sql.Node, error) {
+	if len(expressions) != 1 {
+		return nil, sql.ErrInvalidChildrenNumber.New(c, len(expressions), 1)
+	}
+	newC := *c
+	newC.Runner = expressions[0].(pgexprs.StatementRunner)
+	return &newC, nil
+}
+
+// WithResolvedChildren implements the interface vitess.Injectable.
+func (c *CreateExtension) WithResolvedChildren(ctx context.Context, children []any) (any, error) {
+	if len(children) != 0 {
+		return nil, ErrVitessChildCount.New(0, len(children))
+	}
+	return c, nil
+}