Merge 08492bf31b034a544e5d329164806abcd4d47db8 into 600ea5482c36d3705fbca1d9ab749d9bdafd6f80

plugins/host/storage.go

@@ -0,0 +1,13 @@
+package host
+
+import "context"
+
+// StorageService provides access to a plugin-specific directory with read/write permissions
+//
+//nd:hostservice name=Storage permission=storage
+type StorageService interface {
+	// GetStoragePath retrieves the persistent storage path, if allowed
+	//
+	//nd:hostfunc
+	GetStoragePath(ctx context.Context) string
+}

plugins/host/storage_gen.go

@@ -0,0 +1,67 @@
+// Code generated by ndpgen. DO NOT EDIT.
+
+package host
+
+import (
+	"context"
+	"encoding/json"
+
+	extism "github.com/extism/go-sdk"
+)
+
+// StorageGetStoragePathResponse is the response type for Storage.GetStoragePath.
+type StorageGetStoragePathResponse struct {
+	Result string `json:"result,omitempty"`
+}
+
+// RegisterStorageHostFunctions registers Storage service host functions.
+// The returned host functions should be added to the plugin's configuration.
+func RegisterStorageHostFunctions(service StorageService) []extism.HostFunction {
+	return []extism.HostFunction{
+		newStorageGetStoragePathHostFunction(service),
+	}
+}
+
+func newStorageGetStoragePathHostFunction(service StorageService) extism.HostFunction {
+	return extism.NewHostFunctionWithStack(
+		"storage_getstoragepath",
+		func(ctx context.Context, p *extism.CurrentPlugin, stack []uint64) {
+
+			// Call the service method
+			result := service.GetStoragePath(ctx)
+
+			// Write JSON response to plugin memory
+			resp := StorageGetStoragePathResponse{
+				Result: result,
+			}
+			storageWriteResponse(p, stack, resp)
+		},
+		[]extism.ValueType{extism.ValueTypePTR},
+		[]extism.ValueType{extism.ValueTypePTR},
+	)
+}
+
+// storageWriteResponse writes a JSON response to plugin memory.
+func storageWriteResponse(p *extism.CurrentPlugin, stack []uint64, resp any) {
+	respBytes, err := json.Marshal(resp)
+	if err != nil {
+		storageWriteError(p, stack, err)
+		return
+	}
+	respPtr, err := p.WriteBytes(respBytes)
+	if err != nil {
+		stack[0] = 0
+		return
+	}
+	stack[0] = respPtr
+}
+
+// storageWriteError writes an error response to plugin memory.
+func storageWriteError(p *extism.CurrentPlugin, stack []uint64, err error) {
+	errResp := struct {
+		Error string `json:"error"`
+	}{Error: err.Error()}
+	respBytes, _ := json.Marshal(errResp)
+	respPtr, _ := p.WriteBytes(respBytes)
+	stack[0] = respPtr
+}

plugins/host_storage.go

@@ -0,0 +1,34 @@
+package plugins
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/navidrome/navidrome/conf"
+	"github.com/navidrome/navidrome/plugins/host"
+)
+
+const storageMount = "/storage"
+
+type storageServiceImpl struct{}
+
+func getHostStoragePath(pluginName string) string {
+	return filepath.Join(conf.Server.DataFolder.String(), "plugins", pluginName, "storage")
+}
+
+func newStorageService(pluginName string) (host.StorageService, error) {
+	dataDir := getHostStoragePath(pluginName)
+	if err := os.MkdirAll(dataDir, 0700); err != nil {
+		return nil, fmt.Errorf("creating plugin data directory: %w", err)
+	}
+
+	return &storageServiceImpl{}, nil
+}
+
+func (s *storageServiceImpl) GetStoragePath(ctx context.Context) string {
+	return storageMount
+}
+
+var _ host.StorageService = (*storageServiceImpl)(nil)

plugins/host_storage_test.go

@@ -0,0 +1,264 @@
+//go:build !windows
+
+package plugins
+
+import (
+	"context"
+	"crypto/sha256"
+	"encoding/hex"
+	"fmt"
+	"os"
+	"path/filepath"
+
+	extism "github.com/extism/go-sdk"
+	"github.com/navidrome/navidrome/conf"
+	"github.com/navidrome/navidrome/conf/configtest"
+	"github.com/navidrome/navidrome/model"
+	"github.com/navidrome/navidrome/tests"
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("utility functions", Ordered, func() {
+	var tmpDir string
+
+	BeforeAll(func() {
+		var err error
+		tmpDir, err = os.MkdirTemp("", "storage-test-*")
+		Expect(err).ToNot(HaveOccurred())
+
+		DeferCleanup(configtest.SetupConfig())
+		conf.Server.DataFolder = conf.NewDir(tmpDir)
+
+		DeferCleanup(func() {
+			_ = os.RemoveAll(tmpDir)
+		})
+	})
+
+	Describe("GetHostStoragePath", func() {
+		It("should join data folder, plugins, plugin name, and storage", func() {
+			actual := getHostStoragePath("plugin-name")
+			expected := filepath.Join(tmpDir, "plugins", "plugin-name", "storage")
+			Expect(actual).To(Equal(expected))
+		})
+	})
+
+	Describe("GetStoragePath", func() {
+		It("should return the fixed path", func() {
+			impl := storageServiceImpl{}
+			Expect(impl.GetStoragePath(context.TODO())).To(Equal("/storage"))
+		})
+	})
+
+	Describe("netStorageService", func() {
+		It("should create the directory on init", func() {
+			svc, err := newStorageService("plugin-name")
+			Expect(err).ToNot(HaveOccurred())
+			Expect(svc).ToNot(BeNil())
+
+			dataDir := filepath.Join(tmpDir, "plugins", "plugin-name", "storage")
+			Expect(dataDir).To(BeADirectory())
+		})
+	})
+})
+
+var _ = Describe("Storage Host Function", Ordered, func() {
+	const ID = "test-storage-plugin"
+
+	var (
+		manager   *Manager
+		tmpDir    string
+		router    *fakeSubsonicRouter
+		userRepo  *tests.MockedUserRepo
+		dataStore *tests.MockDataStore
+	)
+
+	BeforeAll(func() {
+		var err error
+		tmpDir, err = os.MkdirTemp("", "storage-test-*")
+		Expect(err).ToNot(HaveOccurred())
+
+		// Setup mock router and data store
+		router = &fakeSubsonicRouter{}
+		userRepo = tests.CreateMockUserRepo()
+		dataStore = &tests.MockDataStore{MockedUser: userRepo}
+
+		// Create and configure manager
+		manager = &Manager{
+			plugins: make(map[string]*plugin),
+			ds:      dataStore,
+		}
+		manager.SetSubsonicRouter(router)
+
+		mockPluginRepo := dataStore.Plugin(GinkgoT().Context()).(*tests.MockPluginRepo)
+		mockPluginRepo.Permitted = true
+
+		// Setup config
+		DeferCleanup(configtest.SetupConfig())
+		conf.Server.DataFolder = conf.NewDir(tmpDir)
+		conf.Server.Plugins.Enabled = true
+		conf.Server.Plugins.Folder = conf.NewDir(tmpDir)
+		conf.Server.Plugins.AutoReload = false
+
+		pluginPaths := []string{ID, ID + "-2"}
+		plugins := []model.Plugin{}
+
+		for idx := range pluginPaths {
+			path := pluginPaths[idx] + PackageExtension
+			// Copy test plugin to temp dir
+			srcPath := filepath.Join(testdataDir, path)
+			destPath := filepath.Join(tmpDir, path)
+			data, err := os.ReadFile(srcPath)
+			Expect(err).ToNot(HaveOccurred())
+			err = os.WriteFile(destPath, data, 0600)
+			Expect(err).ToNot(HaveOccurred())
+
+			// Pre-enable the plugin in the mock repo so it loads on startup
+			// Compute SHA256 of the plugin file to match what syncPlugins will compute
+			pluginPath := filepath.Join(tmpDir, path)
+			wasmData, err := os.ReadFile(pluginPath)
+			Expect(err).ToNot(HaveOccurred())
+			hash := sha256.Sum256(wasmData)
+			hashHex := hex.EncodeToString(hash[:])
+
+			plugins = append(plugins, model.Plugin{
+				ID:       pluginPaths[idx],
+				Path:     pluginPath,
+				SHA256:   hashHex,
+				Enabled:  true,
+				AllUsers: true, // Allow all users for test plugin
+			})
+		}
+
+		mockPluginRepo.SetData(plugins)
+
+		// Start the manager
+		err = manager.Start(GinkgoT().Context())
+		Expect(err).ToNot(HaveOccurred())
+
+		DeferCleanup(func() {
+			_ = manager.Stop()
+			_ = os.RemoveAll(tmpDir)
+		})
+	})
+
+	Describe("Read", func() {
+		var plugin *plugin
+
+		BeforeAll(func() {
+			path := filepath.Join(getHostStoragePath(ID), "real")
+			err := os.WriteFile(path, []byte("1234"), 0600)
+			Expect(err).ToNot(HaveOccurred())
+		})
+
+		BeforeEach(func() {
+			manager.mu.RLock()
+			plugin = manager.plugins[ID]
+			manager.mu.RUnlock()
+			Expect(plugin).ToNot(BeNil())
+		})
+
+		It("should fail to read missing file", func() {
+			instance, err := plugin.instance(GinkgoT().Context())
+			Expect(err).ToNot(HaveOccurred())
+			defer instance.Close(GinkgoT().Context())
+
+			exit, _, err := instance.Call("call_read", []byte("missing"))
+			Expect(exit).To(Equal(uint32(1)))
+			Expect(err).To(HaveOccurred())
+		})
+
+		It("should read an existing file", func() {
+			instance, err := plugin.instance(GinkgoT().Context())
+			Expect(err).ToNot(HaveOccurred())
+			defer instance.Close(GinkgoT().Context())
+
+			exit, output, err := instance.Call("call_read", []byte("real"))
+			Expect(exit).To(Equal(uint32(0)))
+			Expect(err).ToNot(HaveOccurred())
+			Expect(output).To(Equal([]byte("1234")))
+		})
+	})
+
+	Describe("Write", func() {
+		var p *plugin
+
+		BeforeAll(func() {
+			path := filepath.Join(getHostStoragePath(ID), "real")
+			err := os.WriteFile(path, []byte("1234"), 0600)
+			Expect(err).ToNot(HaveOccurred())
+		})
+
+		BeforeEach(func() {
+			manager.mu.RLock()
+			p = manager.plugins[ID]
+			manager.mu.RUnlock()
+			Expect(p).ToNot(BeNil())
+		})
+
+		It("should fail to write to nested file", func() {
+			instance, err := p.instance(GinkgoT().Context())
+			Expect(err).ToNot(HaveOccurred())
+			defer instance.Close(GinkgoT().Context())
+
+			exit, _, err := instance.Call("call_write", []byte(`{"path":"nested/file","contents":"1234"}`))
+			Expect(exit).To(Equal(uint32(1)))
+			Expect(err).To(HaveOccurred())
+		})
+
+		It("should write to a file", func() {
+			instance, err := p.instance(GinkgoT().Context())
+			Expect(err).ToNot(HaveOccurred())
+			defer instance.Close(GinkgoT().Context())
+
+			exit, _, err := instance.Call("call_write", []byte(`{"path":"new","contents":"contents"}`))
+			Expect(exit).To(Equal(uint32(0)))
+			Expect(err).ToNot(HaveOccurred())
+
+			data, err := os.ReadFile(filepath.Join(getHostStoragePath(ID), "new"))
+			Expect(err).ToNot(HaveOccurred())
+			Expect(data).To(Equal([]byte("contents")))
+
+			exit, output, err := instance.Call("call_read", []byte("new"))
+			Expect(exit).To(Equal(uint32(0)))
+			Expect(err).ToNot(HaveOccurred())
+			Expect(output).To(Equal([]byte("contents")))
+		})
+
+		It("should have independent storage for multiple plugins", func() {
+			manager.mu.RLock()
+			plugin2 := manager.plugins[ID+"-2"]
+			manager.mu.RUnlock()
+
+			Expect(plugin2).ToNot(BeNil())
+
+			plugins := []*plugin{p, plugin2}
+			instances := []*extism.Plugin{}
+			names := []string{ID, ID + "-2"}
+
+			for idx := range plugins {
+				instance, err := plugins[idx].instance(GinkgoT().Context())
+				instances = append(instances, instance)
+				Expect(err).ToNot(HaveOccurred())
+				defer instance.Close(GinkgoT().Context())
+
+				exit, _, err := instance.Call("call_write", fmt.Appendf(nil, `{"path":"new","contents":"%s"}`, names[idx]))
+				Expect(exit).To(Equal(uint32(0)))
+				Expect(err).ToNot(HaveOccurred())
+			}
+
+			for idx := range names {
+				data, err := os.ReadFile(filepath.Join(getHostStoragePath(names[idx]), "new"))
+				Expect(err).ToNot(HaveOccurred())
+				Expect(data).To(Equal([]byte(names[idx])))
+			}
+
+			for idx := range plugins {
+				exit, output, err := instances[idx].Call("call_read", []byte("new"))
+				Expect(exit).To(Equal(uint32(0)))
+				Expect(err).ToNot(HaveOccurred())
+				Expect(output).To(Equal([]byte(names[idx])))
+			}
+		})
+	})
+})

plugins/manager_loader.go

@@ -5,6 +5,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
+	"maps"
 	"time"
 
 	extism "github.com/extism/go-sdk"
@@ -166,6 +167,17 @@ var hostServices = []hostServiceEntry{
 			return host.RegisterTaskHostFunctions(service), service, nil
 		},
 	},
+	{
+		name:          "Storage",
+		hasPermission: func(p *Permissions) bool { return p != nil && p.Storage != nil },
+		create: func(ctx *serviceContext) ([]extism.HostFunction, io.Closer, error) {
+			service, err := newStorageService(ctx.pluginName)
+			if err != nil {
+				return nil, nil, err
+			}
+			return host.RegisterStorageHostFunctions(service), nil, nil
+		},
+	},
 }
 
 // extractManifest reads manifest from an .ndp package and computes its SHA-256 hash.
@@ -323,14 +335,24 @@ func (m *Manager) loadPluginWithConfig(p *model.Plugin) error {
 	}
 
 	// Configure filesystem access for library permission
-	if pkg.Manifest.HasLibraryFilesystemPermission() {
-		adminCtx := adminContext(ctx)
-		libraries, err := m.ds.Library(adminCtx).GetAll()
-		if err != nil {
-			return fmt.Errorf("failed to get libraries for filesystem access: %w", err)
+	if pkg.Manifest.HasLibraryFilesystemPermission() || pkg.Manifest.HasStoragePermissions() {
+		allowedPaths := map[string]string{}
+
+		if pkg.Manifest.HasLibraryFilesystemPermission() {
+			adminCtx := adminContext(ctx)
+			libraries, err := m.ds.Library(adminCtx).GetAll()
+			if err != nil {
+				return fmt.Errorf("failed to get libraries for filesystem access: %w", err)
+			}
+
+			libraryPaths := buildAllowedPaths(ctx, libraries, allowedLibraries, p.AllLibraries, p.AllowWriteAccess)
+			maps.Copy(allowedPaths, libraryPaths)
+		}
+
+		if pkg.Manifest.HasStoragePermissions() {
+			allowedPaths[getHostStoragePath(p.ID)] = storageMount
 		}
 
-		allowedPaths := buildAllowedPaths(ctx, libraries, allowedLibraries, p.AllLibraries, p.AllowWriteAccess)
 		pluginManifest.AllowedPaths = allowedPaths
 	}
 

plugins/manifest-schema.json

@@ -92,6 +92,9 @@
         },
         "matcher": {
           "$ref": "#/$defs/MatcherPermission"
+        },
+        "storage": {
+          "$ref": "#/$defs/StoragePermission"
         }
       }
     },
@@ -244,6 +247,17 @@
           "description": "Explanation for why matcher access is needed"
         }
       }
+    },
+    "StoragePermission": {
+      "type": "object",
+      "description": "Storage permissions for enabling persistent read-write storage exclusively for the plugin",
+      "additionalProperties": false,
+      "properties": {
+        "reason": {
+          "type": "string",
+          "description": "Explanation for why storage access is needed"
+        }
+      }
     }
   }
 }

plugins/manifest.go

@@ -123,3 +123,7 @@ func (m *Manifest) HasLibraryFilesystemPermission() bool {
 		m.Permissions.Library != nil &&
 		m.Permissions.Library.Filesystem
 }
+
+func (m *Manifest) HasStoragePermissions() bool {
+	return m.Permissions != nil && m.Permissions.Storage != nil
+}

plugins/manifest_gen.go

@@ -178,6 +178,9 @@ type Permissions struct {
 	// Scheduler corresponds to the JSON schema field "scheduler".
 	Scheduler *SchedulerPermission `json:"scheduler,omitempty" yaml:"scheduler,omitempty" mapstructure:"scheduler,omitempty"`
 
+	// Storage corresponds to the JSON schema field "storage".
+	Storage *StoragePermission `json:"storage,omitempty" yaml:"storage,omitempty" mapstructure:"storage,omitempty"`
+
 	// Subsonicapi corresponds to the JSON schema field "subsonicapi".
 	Subsonicapi *SubsonicAPIPermission `json:"subsonicapi,omitempty" yaml:"subsonicapi,omitempty" mapstructure:"subsonicapi,omitempty"`
 
@@ -197,6 +200,13 @@ type SchedulerPermission struct {
 	Reason *string `json:"reason,omitempty" yaml:"reason,omitempty" mapstructure:"reason,omitempty"`
 }
 
+// Storage permissions for enabling persistent read-write storage exclusively for
+// the plugin
+type StoragePermission struct {
+	// Explanation for why storage access is needed
+	Reason *string `json:"reason,omitempty" yaml:"reason,omitempty" mapstructure:"reason,omitempty"`
+}
+
 // SubsonicAPI service permissions. Requires 'users' permission to be declared.
 type SubsonicAPIPermission struct {
 	// Explanation for why SubsonicAPI access is needed

plugins/pdk/go/host/doc.go

@@ -43,6 +43,7 @@ The following host services are available:
   - Library: provides access to music library metadata for plugins.
   - Matcher: resolves externally-obtained songs to local library tracks,
   - Scheduler: provides task scheduling capabilities for plugins.
+  - Storage: provides access to a plugin-specific directory with read/write permissions
   - SubsonicAPI: provides access to Navidrome's Subsonic API from plugins.
   - Task: provides persistent task queues for plugins.
   - Users: provides access to user information for plugins.

plugins/pdk/go/host/nd_host_storage.go

@@ -0,0 +1,46 @@
+// Code generated by ndpgen. DO NOT EDIT.
+//
+// This file contains client wrappers for the Storage host service.
+// It is intended for use in Navidrome plugins built with TinyGo.
+//
+//go:build wasip1
+
+package host
+
+import (
+	"encoding/json"
+
+	"github.com/navidrome/navidrome/plugins/pdk/go/pdk"
+)
+
+// storage_getstoragepath is the host function provided by Navidrome.
+//
+//go:wasmimport extism:host/user storage_getstoragepath
+func storage_getstoragepath(uint64) uint64
+
+type storageGetStoragePathResponse struct {
+	Result string `json:"result,omitempty"`
+}
+
+// StorageGetStoragePath calls the storage_getstoragepath host function.
+// GetStoragePath retrieves the persistent storage path, if allowed
+func StorageGetStoragePath() string {
+	// No parameters - allocate empty JSON object
+	reqMem := pdk.AllocateBytes([]byte("{}"))
+	defer reqMem.Free()
+
+	// Call the host function
+	responsePtr := storage_getstoragepath(reqMem.Offset())
+
+	// Read the response from memory
+	responseMem := pdk.FindMemory(responsePtr)
+	responseBytes := responseMem.ReadBytes()
+
+	// Parse the response
+	var response storageGetStoragePathResponse
+	if err := json.Unmarshal(responseBytes, &response); err != nil {
+		return ""
+	}
+
+	return response.Result
+}

plugins/pdk/go/host/nd_host_storage_stub.go

@@ -0,0 +1,34 @@
+// Code generated by ndpgen. DO NOT EDIT.
+//
+// This file contains mock implementations for non-WASM builds.
+// These mocks allow IDE support, compilation, and unit testing on non-WASM platforms.
+// Plugin authors can use the exported mock instances to set expectations in tests.
+//
+//go:build !wasip1
+
+package host
+
+import (
+	"github.com/stretchr/testify/mock"
+)
+
+// mockStorageService is the mock implementation for testing.
+type mockStorageService struct {
+	mock.Mock
+}
+
+// StorageMock is the auto-instantiated mock instance for testing.
+// Use this to set expectations: host.StorageMock.On("MethodName", args...).Return(values...)
+var StorageMock = &mockStorageService{}
+
+// GetStoragePath is the mock method for StorageGetStoragePath.
+func (m *mockStorageService) GetStoragePath() string {
+	args := m.Called()
+	return args.String(0)
+}
+
+// StorageGetStoragePath delegates to the mock instance.
+// GetStoragePath retrieves the persistent storage path, if allowed
+func StorageGetStoragePath() string {
+	return StorageMock.GetStoragePath()
+}

plugins/pdk/rust/nd-pdk-host/src/lib.rs

@@ -40,6 +40,7 @@
 //! - [`library`] - provides access to music library metadata for plugins.
 //! - [`matcher`] - resolves externally-obtained songs to local library tracks,
 //! - [`scheduler`] - provides task scheduling capabilities for plugins.
+//! - [`storage`] - provides access to a plugin-specific directory with read/write permissions
 //! - [`subsonicapi`] - provides access to Navidrome's Subsonic API from plugins.
 //! - [`task`] - provides persistent task queues for plugins.
 //! - [`users`] - provides access to user information for plugins.
@@ -101,6 +102,13 @@ pub mod scheduler {
     pub use super::nd_host_scheduler::*;
 }
 
+#[doc(hidden)]
+mod nd_host_storage;
+/// provides access to a plugin-specific directory with read/write permissions
+pub mod storage {
+    pub use super::nd_host_storage::*;
+}
+
 #[doc(hidden)]
 mod nd_host_subsonicapi;
 /// provides access to Navidrome's Subsonic API from plugins.

plugins/pdk/rust/nd-pdk-host/src/nd_host_storage.rs

@@ -0,0 +1,34 @@
+// Code generated by ndpgen. DO NOT EDIT.
+//
+// This file contains client wrappers for the Storage host service.
+// It is intended for use in Navidrome plugins built with extism-pdk.
+
+use extism_pdk::*;
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, Clone, Deserialize)]
+#[serde(rename_all = "camelCase")]
+struct StorageGetStoragePathResponse {
+    #[serde(default)]
+    result: String,
+}
+
+#[host_fn]
+extern "ExtismHost" {
+    fn storage_getstoragepath(input: Json<serde_json::Value>) -> Json<StorageGetStoragePathResponse>;
+}
+
+/// GetStoragePath retrieves the persistent storage path, if allowed
+///
+/// # Returns
+/// The result value.
+///
+/// # Errors
+/// Returns an error if the host function call fails.
+pub fn get_storage_path() -> Result<String, Error> {
+    let response = unsafe {
+        storage_getstoragepath(Json(serde_json::json!({})))?
+    };
+
+    Ok(response.0.result)
+}

plugins/testdata/test-storage-plugin-2

@@ -0,0 +1 @@
+test-storage-plugin

plugins/testdata/test-storage-plugin/go.mod

@@ -0,0 +1,16 @@
+module test-storage-plugin
+
+go 1.25
+
+require github.com/navidrome/navidrome/plugins/pdk/go v0.0.0
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/extism/go-pdk v1.1.3 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/stretchr/objx v0.5.2 // indirect
+	github.com/stretchr/testify v1.11.1 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)
+
+replace github.com/navidrome/navidrome/plugins/pdk/go => ../../pdk/go

plugins/testdata/test-storage-plugin/go.sum

@@ -0,0 +1,14 @@
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/extism/go-pdk v1.1.3 h1:hfViMPWrqjN6u67cIYRALZTZLk/enSPpNKa+rZ9X2SQ=
+github.com/extism/go-pdk v1.1.3/go.mod h1:Gz+LIU/YCKnKXhgge8yo5Yu1F/lbv7KtKFkiCSzW/P4=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/objx v0.5.2 h1:xuMeJ0Sdp5ZMRXx/aWO6RZxdr3beISkG5/G/aIRr3pY=
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+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
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plugins/testdata/test-storage-plugin/main.go

@@ -0,0 +1,50 @@
+// Test plugin for Storage host function integration tests.
+// Build with: tinygo build -o ../test-subsonicapi-plugin.wasm -target wasip1 -buildmode=c-shared ./main.go
+package main
+
+import (
+	"os"
+	"path/filepath"
+
+	"github.com/navidrome/navidrome/plugins/pdk/go/host"
+	"github.com/navidrome/navidrome/plugins/pdk/go/pdk"
+)
+
+//go:wasmexport call_read
+func callRead() int32 {
+	path := filepath.Join(host.StorageGetStoragePath(), pdk.InputString())
+	content, err := os.ReadFile(path)
+	if err != nil {
+		pdk.SetErrorString("failed to read file: " + err.Error())
+		return 1
+	}
+	pdk.Output(content)
+	return 0
+}
+
+type WriteInput struct {
+	Path     string `json:"path"`
+	Contents string `json:"contents"`
+}
+
+//go:wasmexport call_write
+func callWrite() int32 {
+	var config WriteInput
+	err := pdk.InputJSON(&config)
+
+	if err != nil {
+		pdk.SetErrorString("failed to parse json: " + err.Error())
+		return 1
+	}
+
+	path := filepath.Join(host.StorageGetStoragePath(), config.Path)
+	err = os.WriteFile(path, []byte(config.Contents), 0600)
+	if err != nil {
+		pdk.SetErrorString("failed to write file: " + err.Error())
+		return 1
+	}
+
+	return 0
+}
+
+func main() {}

plugins/testdata/test-storage-plugin/manifest.json

@@ -0,0 +1,11 @@
+{
+  "name": "Test SubsonicAPI Plugin",
+  "author": "Navidrome Test",
+  "version": "1.0.0",
+  "description": "Test plugin for SubsonicAPI host function",
+  "permissions": {
+    "storage": {
+      "reason": "persistent storage for testing"
+    }
+  }
+}