Go Requires Chilkat v10.1.2+

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.

Go

    success := false

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

    oauth2 := chilkat.NewOAuth2()

    //  The port should match the Authorized Redirect URL in your Dropbox app, 
    //  which would look like "http://localhost:3017/"
    oauth2.SetListenPort(3017)

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

    oauth2.SetAuthorizationEndpoint("https://www.dropbox.com/oauth2/authorize")
    oauth2.SetTokenEndpoint("https://api.dropboxapi.com/oauth2/token")

    //  Replace this with your actual Dropbox App Key
    oauth2.SetClientId("DROPBOX_APP_KEY")

    //  This is for Require Proof Key for Code Exchange (PKCE)
    //  See OAuth2 PKCE Explained
    oauth2.SetCodeChallenge(true)
    oauth2.SetCodeChallengeMethod("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() == false {
        fmt.Println(oauth2.LastErrorText())
        oauth2.DisposeOAuth2()
        return
    }

    fmt.Println("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 == false {
        fmt.Println(oauth2.LastErrorText())
        oauth2.DisposeOAuth2()
        return
    }

    //  Wait for the user to approve or deny authorization in the browser.
    numMsWaited := 0
    for (numMsWaited < 90000) && (oauth2.AuthFlowState() < 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() < 3 {
        oauth2.Cancel()
        fmt.Println("No response from the browser!")
        oauth2.DisposeOAuth2()
        return
    }

    //  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() == 5 {
        fmt.Println("OAuth2 failed to complete.")
        fmt.Println(oauth2.FailureInfo())
        oauth2.DisposeOAuth2()
        return
    }

    if oauth2.AuthFlowState() == 4 {
        fmt.Println("OAuth2 authorization was denied.")
        fmt.Println(oauth2.AccessTokenResponse())
        oauth2.DisposeOAuth2()
        return
    }

    if oauth2.AuthFlowState() != 3 {
        fmt.Println("Unexpected AuthFlowState:", oauth2.AuthFlowState())
        oauth2.DisposeOAuth2()
        return
    }

    fmt.Println("OAuth2 authorization granted!")

    json := chilkat.NewJsonObject()
    json.Load(oauth2.AccessTokenResponse())
    json.SetEmitCompact(false)

    fmt.Println("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"
    //  }

    fmt.Println("Access Token = ", oauth2.AccessToken())

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

    oauth2.DisposeOAuth2()
    json.DisposeJsonObject()