CloudBridge

Multiple clouds, one Kotlin Multiplatform bridge. Currently supporting web and desktop (JVM), but Android and iOS support is planned.

⚠️ Under construction

This library is not yet stable. The API will change and docs may be outdated.

✨ Features

• ⚡ Unified: One library to access Dropbox, Google Drive and OneDrive.
• 🪶 Lightweight: No need to integrate different SDKs for different platforms.
• 📱 Cross-platform: Currently supports web, but mobile (Android) and desktop (JVM) are planned.

Limited access scopes by using app folders are preferred by the library wherever possible.

☁️ Cloud Services

	Mobile (Android)	Mobile (iOS)	Desktop (JVM)	Web (JS/WASM)
Dropbox	⏳	⏳	✅	✅
Google Drive	⏳	⏳	✅	✅
Microsoft OneDrive	⏳	⏳	✅	✅

✅ = Supported.
⏳ = Planned.

See Compatibility.md for important remarks about each service.

💾 Supported operations

• Folders
  • List content
  • Create/delete folder
• Files
  • Create/update/delete file
  • Download file content
• User
  • Get name and email address

See Compatibility.md for details.

💿 Installation

The library is published to Maven Central.

dependencies {
    implementation("nl.jacobras:cloudbridge:0.5.0")
}

🚀 Quick Start

The main entry point is CloudBridge.dropbox(), CloudBridge.googleDrive() or CloudBridge.oneDrive().

Here's an example with Dropbox. First instantiate the service:

val service = CloudBridge.dropbox() // Pass in token=... if you already have one

Then, have the user authenticate.

Desktop

val authServer = LocalAuthenticationServer()

// Build auth URL and open it in the browser
val url = service.authenticate(
    authServer = authServer,
    clientId = "yourClientId",
    onSuccess = { token -> TODO() })
openBrowser(url)

Web

service.completeAuthentication() // Always call this

// When user wants to authenticate:
service.startAuthenticationByRedirect(
    clientId = "yourClientId",
    redirectUri = "yourRedirectUri"
)

Securely store the token and pass it to the constructor of the service to use it.

Listing files

val service = CloudBridge.dropbox(clientId = "yourClientId")

try {
    service.listFiles()
} catch (e: CloudServiceException) {
    // Handle...
}

📐 Design decisions

Privacy

The library only supports limited/private app folders, no full access.

Paths

The library prefers to work with IDs over paths.

Accounts

Only one account per service is supported as of now.

Types

id and path variables are typed as much as possible, to prevent accidental mix-ups.

Unified error handling

Dropbox will throw 409 when it can't find a path. Other services throw 404 CloudBridge turns them both into CloudServiceException.NotFoundException.

Feel free to open an issue if you have a different use case for any of these.

🔗 Underlying dependencies

Next to Kotlin Multiplatform, this library uses:

• Ktor and Ktorfit for network requests.
• KotlinCrypto hash for SHA256 hashing.
• multiplatform-settings to persist tokens.
• urlencoder for URL encoding.