Lianja

Dropbox: OAuth2 Authorization to Obtain an Access Token

See more Dropbox Examples

Demonstrates how to get a Dropbox OAuth2 access token from a desktop application or script.

This example runs the OAuth 2.0 authorization flow that lets the user sign in to Dropbox and authorize your app.

Lianja

llSuccess = .F.

// For more information about the OAuth2, see OAuth 2.0 Authorization Flow

loOauth2 = createobject("CkOAuth2")

// The port should match the Authorized Redirect URL in your Dropbox app, 
// which would look like "http://localhost:3017/"
loOauth2.ListenPort = 3017

// IMPORTANT: One of the OAuth2 redirect URIs for your Dropbox app must be
// exactly this string:  http://localhost:3017/

loOauth2.AuthorizationEndpoint = "https://www.dropbox.com/oauth2/authorize"
loOauth2.TokenEndpoint = "https://api.dropboxapi.com/oauth2/token"

// Replace this with your actual Dropbox App Key
loOauth2.ClientId = "DROPBOX_APP_KEY"

// This is for Require Proof Key for Code Exchange (PKCE)
// See OAuth2 PKCE Explained
loOauth2.CodeChallenge = .T.
loOauth2.CodeChallengeMethod = "S256"

// Add token_access_type=offline to also get a refresh token in the response
loOauth2.AddAuthQueryParam("token_access_type","offline")

// Begin the OAuth2 Authorization code flow.  This returns a URL that should be loaded in a browser.
lcUrl = loOauth2.StartAuth()
if (loOauth2.LastMethodSuccess <> .T.) then
    ? loOauth2.LastErrorText
    release loOauth2
    return
endif

? "url = " + lcUrl

// Launch the default browser on the system and navigate to the url.
// The LaunchBrowser method was added in Chilkat v10.1.2.
llSuccess = loOauth2.LaunchBrowser(lcUrl)
if (llSuccess = .F.) then
    ? loOauth2.LastErrorText
    release loOauth2
    return
endif

// Wait for the user to approve or deny authorization in the browser.
lnNumMsWaited = 0
do while (lnNumMsWaited < 90000) and (loOauth2.AuthFlowState < 3)
    loOauth2.SleepMs(100)
    lnNumMsWaited = lnNumMsWaited + 100
enddo

// If the browser does not respond within the specified time, AuthFlowState will be:
// 
// 1: Waiting for Redirect - The OAuth2 background thread is waiting for the browser's redirect request.
// 2: Waiting for Final Response - The thread is awaiting the final access token response.
// In either case, cancel the background task initiated by StartAuth.

if (loOauth2.AuthFlowState < 3) then
    loOauth2.Cancel()
    ? "No response from the browser!"
    release loOauth2
    return
endif

// Check AuthFlowState to determine if authorization was granted, denied, or failed:
// 
// 3: Success - OAuth2 flow completed, the background thread exited, and the successful response is in AccessTokenResponse.
// 4: Access Denied - OAuth2 flow completed, the background thread exited, and the error response is in AccessTokenResponse.
// 5: Failure - OAuth2 flow failed before completion, the background thread exited, and error details are in FailureInfo.

if (loOauth2.AuthFlowState = 5) then
    ? "OAuth2 failed to complete."
    ? loOauth2.FailureInfo
    release loOauth2
    return
endif

if (loOauth2.AuthFlowState = 4) then
    ? "OAuth2 authorization was denied."
    ? loOauth2.AccessTokenResponse
    release loOauth2
    return
endif

if (loOauth2.AuthFlowState <> 3) then
    ? "Unexpected AuthFlowState:" + str(loOauth2.AuthFlowState)
    release loOauth2
    return
endif

? "OAuth2 authorization granted!"

loJson = createobject("CkJsonObject")
loJson.Load(loOauth2.AccessTokenResponse)
loJson.EmitCompact = .F.

? "Access Token Response = " + loJson.Emit()

// A sample access token response:

// {
//   "access_token": "...",
//   "token_type": "bearer",
//   "expires_in": 14399,
//   "refresh_token": "...",
//   "scope": "account_info.read",
//   "uid": "562542581",
//   "account_id": "dbid:AACQhDS0E3_Vb72Ynd0F-GxGWdTI2qcTHzA"
// }

? "Access Token = " + loOauth2.AccessToken

// Save the JSON access token response to a file for subsequent use..
loJson.WriteFile("qa_data/tokens/dropbox.json")


release loOauth2
release loJson