Do not write files to file system

modules/redpanda/redpanda.go

@@ -10,7 +10,6 @@ import (
 	"fmt"
 	"math"
 	"net/http"
-	"os"
 	"path/filepath"
 	"strings"
 	"text/template"
@@ -61,12 +60,6 @@ func RunContainer(ctx context.Context, opts ...testcontainers.ContainerCustomize
 
 // Run creates an instance of the Redpanda container type
 func Run(ctx context.Context, img string, opts ...testcontainers.ContainerCustomizer) (*Container, error) {
-	tmpDir, err := os.MkdirTemp("", "redpanda")
-	if err != nil {
-		return nil, fmt.Errorf("create temporary directory: %w", err)
-	}
-	defer os.RemoveAll(tmpDir)
-
 	// 1. Create container request.
 	// Some (e.g. Image) may be overridden by providing an option argument to this function.
 	req := testcontainers.GenericContainerRequest{
@@ -114,66 +107,47 @@ func Run(ctx context.Context, img string, opts ...testcontainers.ContainerCustom
 		settings.EnableWasmTransform = false
 	}
 
-	// 3. Create temporary entrypoint file. We need a custom entrypoint that waits
-	// until the actual Redpanda node config is mounted. Once the redpanda config is
-	// mounted we will call the original entrypoint with the same parameters.
-	// We have to do this kind of two-step process, because we need to know the mapped
-	// port, so that we can use this in Redpanda's advertised listeners configuration for
-	// the Kafka API.
-	entrypointPath := filepath.Join(tmpDir, entrypointFile)
-	if err := os.WriteFile(entrypointPath, entrypoint, 0o700); err != nil {
-		return nil, fmt.Errorf("write entrypoint file: %w", err)
-	}
-
-	// 4. Register extra kafka listeners if provided, network aliases will be
+	// 3. Register extra kafka listeners if provided, network aliases will be
 	// set
 	if err := registerListeners(settings, req); err != nil {
 		return nil, fmt.Errorf("register listeners: %w", err)
 	}
 
 	// Bootstrap config file contains cluster configurations which will only be considered
 	// the very first time you start a cluster.
-	bootstrapConfigPath := filepath.Join(tmpDir, bootstrapConfigFile)
 	bootstrapConfig, err := renderBootstrapConfig(settings)
 	if err != nil {
 		return nil, err
 	}
-	if err := os.WriteFile(bootstrapConfigPath, bootstrapConfig, 0o600); err != nil {
-		return nil, fmt.Errorf("write bootstrap config: %w", err)
-	}
 
+	// We need a custom entrypoint that waits until the actual Redpanda node config is mounted.
+	// Once the redpanda config is mounted we will call the original entrypoint with the same parameters.
+	// We have to do this kind of two-step process, because we need to know the mapped
+	// port, so that we can use this in Redpanda's advertised listeners configuration for
+	// the Kafka API.
 	req.Files = append(req.Files,
 		testcontainers.ContainerFile{
-			HostFilePath:      entrypointPath,
+			Reader:            bytes.NewReader(entrypoint),
 			ContainerFilePath: entrypointFile,
 			FileMode:          700,
 		},
 		testcontainers.ContainerFile{
-			HostFilePath:      bootstrapConfigPath,
+			Reader:            bytes.NewReader(bootstrapConfig),
 			ContainerFilePath: filepath.Join(redpandaDir, bootstrapConfigFile),
 			FileMode:          600,
 		},
 	)
 
-	// 5. Create certificate and key for TLS connections.
+	// 4. Create certificate and key for TLS connections.
 	if settings.EnableTLS {
-		certPath := filepath.Join(tmpDir, certFile)
-		if err := os.WriteFile(certPath, settings.cert, 0o600); err != nil {
-			return nil, fmt.Errorf("write certificate file: %w", err)
-		}
-		keyPath := filepath.Join(tmpDir, keyFile)
-		if err := os.WriteFile(keyPath, settings.key, 0o600); err != nil {
-			return nil, fmt.Errorf("write key file: %w", err)
-		}
-
 		req.Files = append(req.Files,
 			testcontainers.ContainerFile{
-				HostFilePath:      certPath,
+				Reader:            bytes.NewReader(settings.cert),
 				ContainerFilePath: filepath.Join(redpandaDir, certFile),
 				FileMode:          600,
 			},
 			testcontainers.ContainerFile{
-				HostFilePath:      keyPath,
+				Reader:            bytes.NewReader(settings.key),
 				ContainerFilePath: filepath.Join(redpandaDir, keyFile),
 				FileMode:          600,
 			},
@@ -189,7 +163,7 @@ func Run(ctx context.Context, img string, opts ...testcontainers.ContainerCustom
 		return c, fmt.Errorf("generic container: %w", err)
 	}
 
-	// 6. Get mapped port for the Kafka API, so that we can render and then mount
+	// 5. Get mapped port for the Kafka API, so that we can render and then mount
 	// the Redpanda config with the advertised Kafka address.
 	hostIP, err := ctr.Host(ctx)
 	if err != nil {
@@ -201,7 +175,7 @@ func Run(ctx context.Context, img string, opts ...testcontainers.ContainerCustom
 		return c, fmt.Errorf("mapped kafka port: %w", err)
 	}
 
-	// 7. Render redpanda.yaml config and mount it.
+	// 6. Render redpanda.yaml config and mount it.
 	nodeConfig, err := renderNodeConfig(settings, hostIP, kafkaPort.Int())
 	if err != nil {
 		return c, err
@@ -212,7 +186,7 @@ func Run(ctx context.Context, img string, opts ...testcontainers.ContainerCustom
 		return c, fmt.Errorf("copy to container: %w", err)
 	}
 
-	// 8. Wait until Redpanda is ready to serve requests.
+	// 7. Wait until Redpanda is ready to serve requests.
 	waitHTTP := wait.ForHTTP(defaultAdminAPIPort).
 		WithStatusCodeMatcher(func(status int) bool {
 			// Redpanda's admin API returns 404 for requests to "/".
@@ -248,7 +222,7 @@ func Run(ctx context.Context, img string, opts ...testcontainers.ContainerCustom
 		c.urlScheme += "s"
 	}
 
-	// 9. Create Redpanda Service Accounts if configured to do so.
+	// 8. Create Redpanda Service Accounts if configured to do so.
 	if len(settings.ServiceAccounts) > 0 {
 		adminAPIPort, err := ctr.MappedPort(ctx, nat.Port(defaultAdminAPIPort))
 		if err != nil {