PowerShell

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.

PowerShell

Add-Type -Path "C:\chilkat\ChilkatDotNet47-x64\ChilkatDotNet47.dll"

$success = $false

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

$oauth2 = New-Object Chilkat.OAuth2

# The port should match the Authorized Redirect URL in your Dropbox app, 
# which would look like "http://localhost:3017/"
$oauth2.ListenPort = 3017

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

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

# Replace this with your actual Dropbox App Key
$oauth2.ClientId = "DROPBOX_APP_KEY"

# This is for Require Proof Key for Code Exchange (PKCE)
# See OAuth2 PKCE Explained
$oauth2.CodeChallenge = $true
$oauth2.CodeChallengeMethod = "S256"

# Add token_access_type=offline to also get a refresh token in the response
$oauth2.AddAuthQueryParam("token_access_type","offline")

# Begin the OAuth2 Authorization code flow.  This returns a URL that should be loaded in a browser.
$url = $oauth2.StartAuth()
if ($oauth2.LastMethodSuccess -ne $true) {
    $($oauth2.LastErrorText)
    exit
}

$("url = " + $url)

# Launch the default browser on the system and navigate to the url.
# The LaunchBrowser method was added in Chilkat v10.1.2.
$success = $oauth2.LaunchBrowser($url)
if ($success -eq $false) {
    $($oauth2.LastErrorText)
    exit
}

# Wait for the user to approve or deny authorization in the browser.
$numMsWaited = 0
while (($numMsWaited -lt 90000) -and ($oauth2.AuthFlowState -lt 3)) {
    $oauth2.SleepMs(100)
    $numMsWaited = $numMsWaited + 100
}

# 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 ($oauth2.AuthFlowState -lt 3) {
    $oauth2.Cancel()
    $("No response from the browser!")
    exit
}

# 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 ($oauth2.AuthFlowState -eq 5) {
    $("OAuth2 failed to complete.")
    $($oauth2.FailureInfo)
    exit
}

if ($oauth2.AuthFlowState -eq 4) {
    $("OAuth2 authorization was denied.")
    $($oauth2.AccessTokenResponse)
    exit
}

if ($oauth2.AuthFlowState -ne 3) {
    $("Unexpected AuthFlowState:" + $oauth2.AuthFlowState)
    exit
}

$("OAuth2 authorization granted!")

$json = New-Object Chilkat.JsonObject
$json.Load($oauth2.AccessTokenResponse)
$json.EmitCompact = $false

$("Access Token Response = " + $json.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 = " + $oauth2.AccessToken)

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