IFileService
Overview
A file service class is defined in a TypeScript or JavaScript file that’s created in the src/services
directory.
The class must extend the AbstractFileService
class imported from the @medusajs/medusa
package.
Based on services’ naming conventions, the file’s name should be the slug version of the file service’s name
without service
, and the class’s name should be the pascal case of the file service’s name following by Service
.
For example, create the file src/services/local-file.ts
with the following content:
import { AbstractFileService } from "@medusajs/medusa"
import {
DeleteFileType,
FileServiceGetUploadStreamResult,
FileServiceUploadResult,
GetUploadedFileType,
UploadStreamDescriptorType,
} from "@medusajs/types"
class LocalFileService extends AbstractFileService {
async upload(
fileData: Express.Multer.File
): Promise<FileServiceUploadResult> {
throw new Error("Method not implemented.")
}
async uploadProtected(
fileData: Express.Multer.File
): Promise<FileServiceUploadResult> {
throw new Error("Method not implemented.")
}
async delete(fileData: DeleteFileType): Promise<void> {
throw new Error("Method not implemented.")
}
async getUploadStreamDescriptor(
fileData: UploadStreamDescriptorType
): Promise<FileServiceGetUploadStreamResult> {
throw new Error("Method not implemented.")
}
async getDownloadStream(
fileData: GetUploadedFileType
): Promise<NodeJS.ReadableStream> {
throw new Error("Method not implemented.")
}
async getPresignedDownloadUrl(
fileData: GetUploadedFileType
): Promise<string> {
throw new Error("Method not implemented.")
}
}
export default LocalFileService
The examples implement a file service supporting local uploads.
If you’re using TypeScript and you're following along with the implementation, you should install the Multer types package in the root of your Medusa backend to resolve errors within your file service types:
Properties
manager_
EntityManagerRequiredtransactionManager_
undefined | EntityManagerRequired__container__
anyRequired__configModule__
Record<string, unknown>__moduleDeclaration__
Record<string, unknown>Accessors
activeManager_
Returns
EntityManager
EntityManagerRequiredMethods
upload
This method is used to upload a file to the Medusa backend.
Example
class LocalFileService extends AbstractFileService {
// ...
async upload(
fileData: Express.Multer.File
): Promise<FileServiceUploadResult> {
const filePath =
`${this.publicPath}/${fileData.originalname}`
fs.copyFileSync(fileData.path, filePath)
return {
url: `${this.serverUrl}/${filePath}`,
key: filePath,
}
}
// ...
}
This example does not account for duplicate names to maintain simplicity in this guide. So, an uploaded file can replace another existing file that has the same name.
Parameters
file
FileRequiredpath
property of the file object.Returns
The details of the upload's result.
uploadProtected
This method is used to upload a file to the Medusa backend, but to a protected storage. Typically, this would be used to store files that shouldn’t be accessible by using the file’s URL or should only be accessible by authenticated users. For example, exported or imported CSV files.
Example
class LocalFileService extends AbstractFileService {
// ...
async uploadProtected(
fileData: Express.Multer.File
): Promise<FileServiceUploadResult> {
const filePath =
`${this.protectedPath}/${fileData.originalname}`
fs.copyFileSync(fileData.path, filePath)
return {
url: `${this.serverUrl}/${filePath}`,
key: filePath
}
}
// ...
}
This example does not account for duplicate names to maintain simplicity in this guide. So, an uploaded file can replace another existing file that has the same name.
Parameters
file
FileRequiredpath
property of the file object.Returns
The details of the upload's result.
delete
This method is used to delete a file from storage.
Example
Parameters
The details of the file to remove.
Returns
Promise
Promise<void>RequiredgetUploadStreamDescriptor
This method is used to retrieve a write stream to be used to upload a file.
Example
// ...
import { Stream } from "stream"
class LocalFileService extends AbstractFileService {
// ...
async getUploadStreamDescriptor({
name,
ext,
isPrivate = true,
}: UploadStreamDescriptorType
): Promise<FileServiceGetUploadStreamResult> {
const filePath = `${isPrivate ?
this.publicPath : this.protectedPath
}/${name}.${ext}`
const pass = new Stream.PassThrough()
const writeStream = fs.createWriteStream(filePath)
pass.pipe(writeStream)
return {
writeStream: pass,
promise: Promise.resolve(),
url: `${this.serverUrl}/${filePath}`,
fileKey: filePath,
}
}
// ...
}
Parameters
The details of the file being uploaded.
Returns
The result of the file-stream upload.
getDownloadStream
This method is used to retrieve a read stream for a file, which can then be used to download the file.
Example
class LocalFileService extends AbstractFileService {
async getDownloadStream({
fileKey,
isPrivate = true,
}: GetUploadedFileType
): Promise<NodeJS.ReadableStream> {
const filePath = `${isPrivate ?
this.publicPath : this.protectedPath
}/${fileKey}`
const readStream = fs.createReadStream(filePath)
return readStream
}
// ...
}
Parameters
The details of the file.
Returns
Promise
Promise<ReadableStream>RequiredThe read stream to read and download the file.
Promise
Promise<ReadableStream>RequiredgetPresignedDownloadUrl
This method is used to retrieve a download URL of the file. For some file services, such as S3, a presigned URL indicates a temporary URL to get access to a file.
If your file service doesn’t perform or offer a similar functionality, you can just return the URL to download the file.
Example
class LocalFileService extends AbstractFileService {
async getPresignedDownloadUrl({
fileKey,
isPrivate = true,
}: GetUploadedFileType
): Promise<string> {
// Local upload doesn't provide
// support for presigned URLs,
// so just return the file's URL.
const filePath = `${isPrivate ?
this.publicPath : this.protectedPath
}/${fileKey}`
return `${this.serverUrl}/${filePath}`
}
// ...
}
Parameters
The details of the file.
Returns
Promise
Promise<string>RequiredThe presigned URL to download the file
Promise
Promise<string>RequiredwithTransaction
Parameters
transactionManager
EntityManagerReturns
this
thisRequiredshouldRetryTransaction_
Parameters
err
Record<string, unknown> | objectRequiredReturns
boolean
booleanRequiredatomicPhase_
Wraps some work within a transactional block. If the service already has a transaction manager attached this will be reused, otherwise a new transaction manager is created.
Type Parameters
TResult
objectRequiredTError
objectRequiredParameters
work
(transactionManager: EntityManager) => Promise<TResult>RequiredisolationOrErrorHandler
IsolationLevel | (error: TError) => Promise<void | TResult>maybeErrorHandlerOrDontFail
(error: TError) => Promise<void | TResult>Returns
Promise
Promise<TResult>Requiredthe result of the transactional work
Promise
Promise<TResult>Required