fix(redpanda): temporary file use

Fix Redpanda compatibility with read only environments by eliminating
the use of local filesystem any more, it now uses io.Reader now to copy
files to the container.

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 {