0.5.4 • Published 4 years ago
@paroi/media-engine v0.5.4
@paroi/media-engine
A backend library to upload and store files in SQLite, then to serve them.
How to create a MediaStorage
The MediaStorage
stores the files in a relational database. It resizes images in the configured dimensions.
Open a connection with LADC using the adapter for SQLite and the integration with the query builder SQL Bricks:
npm install @paroi/media-engine ladc @ladc/sqlite3-adapter @ladc/sql-bricks-modifier
import ladc from "ladc"
import sqlite3Adapter from "@ladc/sqlite3-adapter"
import sqlBricksModifier from "@ladc/sql-bricks-modifier"
let cn = ladc({
adapter: sqlite3Adapter({ fileName: "path/to/db.sqlite" }),
modifier: sqlBricksModifier()
}
Then, create the storage:
export async function createStorage(cn: import("@ladc/sql-bricks-modifier").SBMainConnection, execDdl: boolean) {
return await createMediaStorage({
execInitScript: execDdl ? "sqlite" : undefined,
cn,
imagesConf: IMAGES_CONF
})
}
const IMAGES_CONF: import("@paroi/media-engine").ImageVariantsConfiguration = {
"imageType1": [
{
code: "34x34",
width: 68,
height: 68,
mediaType: "image/png"
},
{
code: "200x200",
width: 200,
height: 200,
mediaType: "image/jpeg"
}
],
"imageType2": [
{
code: "200x100",
width: 200,
height: 100,
embed: true,
mediaType: "image/jpeg"
}
]
}
Notice: The MediaStorage
can be used without an UploadEngine
.
How to create an UploadEngine
The UploadEngine
declares and implements the routes to express
.
Here is how to create an UploadEngine
:
import { Request } from "express"
import { ExternalRef, MediaRef, Media, MulterFile, MediaStorage, createMediaStorage, isSupportedImage } from "@paroi/media-engine"
import { createUploadEngine, UploadEngine, UploadEngineManager } from "@paroi/media-engine/upload"
export async function createUpload(storage: MediaStorage) {
return createUploadEngine({
manager: createUploadEngineManager(storage),
storage,
baseUrl: `url/to/medias`
})
}
function createUploadEngineManager(storage: MediaStorage): UploadEngineManager {
return {
canUpload(req: Request, externalRef: ExternalRef, overwrite: boolean, file: MulterFile) {
return {
canUpload: true,
ownerId: "123"
}
},
async makeJsonResponseForUpload(req: Request, mediaId: string, overwritten: boolean) {
return { /* your JSON response */ }
},
canRead(req: Request, mediaRef: MediaRef) {
return true
},
canDelete(req: Request, mediaRef: MediaRef) {
return true
},
async makeJsonResponseForDelete(req: Request, deletedMedia: Media) {
return { /* your JSON response */ }
}
}
}
Then, let it declare the routes:
const express = require("express")
let router = express.Router()
uploadEngine.declareRoutes(router)
let app = express()
app.use(router)
let server = http.createServer(app)
server.listen(8080)
Now, three routes are available:
url/to/medias/upload
(POST
) Upload a file and create a media. A JSON object of typeUploadedFile
must be sent as a parameter with the file.url/to/medias/delete
(POST
) Delete a media. A JSON object of type{ mediaId: string }
must be sent as a request body.url/to/medias/:year/:variantId/:fileName?download=1
(GET
) Serve a file. An optional URL parameterdownload
can be set.
The UploadedFile
type:
interface UploadedFile {
ref {
type: string
id: string
}
overwrite?: boolean
}