feat(mssql): add WithInitSQL function

docs/modules/mssql.md

@@ -48,6 +48,23 @@ func Run(ctx context.Context, img string, opts ...testcontainers.ContainerCustom
 
 When starting the MS SQL Server container, you can pass options in a variadic way to configure it.
 
+#### Init Scripts
+
+- Not available until the next release of testcontainers-go <a href="https://github.com/testcontainers/testcontainers-go"><span class="tc-version">:material-tag: main</span></a>
+
+If you need to execute SQL files when the container starts, you can use `mssql.WithInitSQL(files
+...io.Reader)` with one or more `*.sql` files. The files will be executed in order after the
+container is ready.
+
+<!--codeinclude-->
+[Example of SQL script](../../modules/mssql/testdata/seed.sql)
+<!--/codeinclude-->
+
+This will:
+
+1. Copy each file into the container.
+2. Execute them using `sqlcmd` after the container is ready.
+
 #### Image
 
 If you need to set a different MS SQL Server Docker image, you can set a valid Docker image as the second argument in the `Run` function.

modules/mssql/mssql.go

@@ -3,9 +3,11 @@ package mssql
 import (
 	"context"
 	"fmt"
+	"io"
 	"strings"
 
 	"github.com/testcontainers/testcontainers-go"
+	tcexec "github.com/testcontainers/testcontainers-go/exec"
 	"github.com/testcontainers/testcontainers-go/wait"
 )
 
@@ -41,6 +43,58 @@ func WithPassword(password string) testcontainers.CustomizeRequestOption {
 	}
 }
 
+// WithInitSQL adds SQL scripts to be executed after the container is ready.
+// The scripts are executed in the order they are provided using sqlcmd tool.
+func WithInitSQL(files ...io.Reader) testcontainers.CustomizeRequestOption {
+	return func(req *testcontainers.GenericContainerRequest) error {
+		hooks := make([]testcontainers.ContainerHook, 0, len(files))
+
+		for i, script := range files {
+			content, err := io.ReadAll(script)
+			if err != nil {
+				return fmt.Errorf("failed to read script: %w", err)
+			}
+
+			hook := func(ctx context.Context, c testcontainers.Container) error {
+				password := defaultPassword
+				if req.Env["MSSQL_SA_PASSWORD"] != "" {
+					password = req.Env["MSSQL_SA_PASSWORD"]
+				}
+
+				// targetPath is a dummy path to store the script in the container
+				targetPath := "/tmp/" + fmt.Sprintf("script_%d.sql", i)
+				if err := c.CopyToContainer(ctx, content, targetPath, 0o644); err != nil {
+					return fmt.Errorf("failed to copy script to container: %w", err)
+				}
+
+				// NOTE: we add both legacy and new mssql-tools paths to ensure compatibility
+				envOpts := tcexec.WithEnv([]string{
+					"PATH=/opt/mssql-tools18/bin:/opt/mssql-tools/bin:$PATH",
+				})
+				cmd := []string{
+					"sqlcmd",
+					"-S", "localhost",
+					"-U", defaultUsername,
+					"-P", password,
+					"-No",
+					"-i", targetPath,
+				}
+				if _, _, err := c.Exec(ctx, cmd, envOpts); err != nil {
+					return fmt.Errorf("failed to execute SQL script %q using sqlcmd: %w", targetPath, err)
+				}
+				return nil
+			}
+			hooks = append(hooks, hook)
+		}
+
+		req.LifecycleHooks = append(req.LifecycleHooks, testcontainers.ContainerLifecycleHooks{
+			PostReadies: hooks,
+		})
+
+		return nil
+	}
+}
+
 // Deprecated: use Run instead
 // RunContainer creates an instance of the MSSQLServer container type
 func RunContainer(ctx context.Context, opts ...testcontainers.ContainerCustomizer) (*MSSQLServerContainer, error) {

modules/mssql/mssql_test.go

@@ -1,8 +1,10 @@
 package mssql_test
 
 import (
+	"bytes"
 	"context"
 	"database/sql"
+	_ "embed"
 	"testing"
 
 	_ "github.com/microsoft/go-mssqldb"
@@ -128,3 +130,84 @@ func TestMSSQLServerWithInvalidPassword(t *testing.T) {
 	testcontainers.CleanupContainer(t, ctr)
 	require.NoError(t, err)
 }
+
+//go:embed testdata/seed.sql
+var seedSQLContent []byte
+
+// tests that a container can be created with a DDL script
+func TestMSSQLServerWithScriptsDDL(t *testing.T) {
+	const password = "MyCustom@Passw0rd"
+
+	// assertContainer contains the logic for asserting the test
+	assertContainer := func(t *testing.T, ctx context.Context, image string, options ...testcontainers.ContainerCustomizer) {
+		t.Helper()
+
+		ctr, err := mssql.Run(ctx,
+			image,
+			append([]testcontainers.ContainerCustomizer{mssql.WithAcceptEULA()}, options...)...,
+		)
+		testcontainers.CleanupContainer(t, ctr)
+		require.NoError(t, err)
+
+		connectionString, err := ctr.ConnectionString(ctx)
+		require.NoError(t, err)
+
+		db, err := sql.Open("sqlserver", connectionString)
+		require.NoError(t, err)
+		defer db.Close()
+
+		err = db.PingContext(ctx)
+		require.NoError(t, err)
+
+		rows, err := db.QueryContext(ctx, "SELECT * FROM pizza_palace.pizzas")
+		require.NoError(t, err)
+		defer rows.Close()
+
+		type Pizza struct {
+			ID            int
+			ToppingName   string
+			Deliciousness string
+		}
+
+		want := []Pizza{
+			{1, "Pineapple", "Controversial but tasty"},
+			{2, "Pepperoni", "Classic never fails"},
+		}
+		got := make([]Pizza, 0, len(want))
+
+		for rows.Next() {
+			var p Pizza
+			err := rows.Scan(&p.ID, &p.ToppingName, &p.Deliciousness)
+			require.NoError(t, err)
+			got = append(got, p)
+		}
+
+		require.EqualValues(t, want, got)
+	}
+
+	ctx := context.Background()
+
+	t.Run("WithPassword/beforeWithScripts", func(t *testing.T) {
+		assertContainer(t, ctx,
+			"mcr.microsoft.com/mssql/server:2022-CU14-ubuntu-22.04",
+			mssql.WithPassword(password),
+			mssql.WithInitSQL(bytes.NewReader(seedSQLContent)),
+		)
+	})
+
+	t.Run("WithPassword/afterWithScripts", func(t *testing.T) {
+		assertContainer(t, ctx,
+			"mcr.microsoft.com/mssql/server:2022-CU14-ubuntu-22.04",
+			mssql.WithInitSQL(bytes.NewReader(seedSQLContent)),
+			mssql.WithPassword(password),
+		)
+	})
+
+	t.Run("2019-CU30-ubuntu-20.04/oldSQLCmd", func(t *testing.T) {
+		assertContainer(t, ctx,
+			"mcr.microsoft.com/mssql/server:2019-CU30-ubuntu-20.04",
+			mssql.WithPassword(password),
+			mssql.WithInitSQL(bytes.NewReader(seedSQLContent)),
+		)
+	})
+}

modules/mssql/testdata/seed.sql

@@ -0,0 +1,14 @@
+CREATE SCHEMA pizza_palace;
+GO
+
+CREATE TABLE pizza_palace.pizzas (
+    ID INT PRIMARY KEY IDENTITY,
+    ToppingName NVARCHAR(100),
+    Deliciousness NVARCHAR(100) UNIQUE
+);
+GO
+
+INSERT INTO pizza_palace.pizzas (ToppingName, Deliciousness) VALUES
+    ('Pineapple', 'Controversial but tasty'),
+    ('Pepperoni', 'Classic never fails')
+GO