Cmdlets for Trello

Build 24.0.9060

Establishing a Connection

With the CData Cmdlets users can install a data module, set the connection properties, and start scripting. This section provides examples of using our Trello Cmdlets with native PowerShell cmdlets, like the CSV import and export cmdlets.

Installing and Connecting

If you have PSGet, installing the cmdlets can be accomplished from the PowerShell Gallery with the following command. You can also obtain a setup from the CData site. 

Install-Module TrelloCmdlets

The following line is then added to your profile, loading the cmdlets on the next session: 

Import-Module TrelloCmdlets;

You can then use the Connect-Trello cmdlet to create a connection object that can be passed to other cmdlets: 

$conn = Connect-Trello -APIKey "myApiKey" -Token="myGeneratedToken"

Connecting to Trello

Trello uses token-based authentication to grant third-party applications access to their API. When a user has granted an application access to their data, the application is given a token that can be used to make requests to Trello's API.

The Trello API can be accessed either via Trello's own Authorization Route, or via OAuth.

Trello Authorization Route

At the moment of registration, Trello assigns an API key and Token to the account.

To activate access via Authorization Route:

  1. Set AuthScheme to Token.
  2. Retrieve the account's API key:
    • Log into Trello
    • Visit https://trello.com/app-key.
  3. Adjust this url: https://trello.com/1/authorize?expiration=never&name=MyPersonalToken&scope=read,write,account&response_type=token&key={Key} changing key to the API key you just obtained.
  4. Visit the url.
  5. To change the token's expiration time, modify the expiration= field. Legal values are 1hour, 1day, 30days, and never.
  6. To authorize the application to use your account, click Allow. Trello redirects you to a page with your token.
  7. Set the following connection properties:
    • APIKey = the key found at https://trello.com/app-key.
    • Token = the token you just obtained.

After you have secured both the API key and the Token, you are ready to make requests to the Trello API.

OAuth

Similar to using Authorization, OAuth creates an Application Id and Secret when you create your account. To authenticate via OAuth, from the Web, a Desktop, or a Headless Server, you must set AuthScheme to OAuth, and you must create a custom OAuth application, as described in Creating a Custom OAuth Application.

The following subsections describe how to authenticate to Trello from three common authentication flows:

  • Desktop: a connection to a server on the user's local machine, frequently used for testing and prototyping.
  • Web: access to data via a shared website.
  • Headless Server: a dedicated computer that provides services to other computers and their users, which is configured to operate without a monitor and keyboard.

For information about how to create a custom OAuth application, see Creating a Custom OAuth Application.

For a complete list of connection string properties available in Trello, see Connection.

Desktop Applications

To authenticate with the credentials for a custom OAuth application, you must get and refresh the OAuth access token. After you do that, you are ready to connect.

Get and refresh the OAuth access token:

  • InitiateOAuth = GETANDREFRESH. Used to automatically get and refresh the OAuthAccessToken.
  • OAuthClientId = the client Id assigned when you registered your application.
  • OAuthClientSecret = the client secret that was assigned when you registered your application.
  • CallbackURL = the redirect URI that was defined when you registered your application.

When you connect, the cmdlet opens Trello's OAuth endpoint in your default browser. Log in and grant permissions to the application.

When the access token expires, the cmdlet refreshes it automatically.

Automatic refresh of the OAuth access token:

To have the cmdlet automatically refresh the OAuth access token, do the following:

  1. Before connecting to data for the first time, set the following connection parameters:
    • InitiateOAuth = REFRESH.
    • OAuthClientId = the client Id in your application settings.
    • OAuthClientSecret = the client secret in your application settings.
    • OAuthAccessToken = the access token returned by GetOAuthAccessToken.
    • OAuthSettingsLocation = the path where you want the cmdlet to save the OAuth values, which persist across connections.
  2. On subsequent data connections, set the following:
    • InitiateOAuth
    • OAuthSettingsLocation

Headless Machines

If you need to log in to a resource that resides on a headless machine, you must authenticate on another device that has an internet browser. You can do this in either of the following ways:

  • Option 1: Obtain the OAuthVerifier value.
  • Option 2: Install the cmdlet on a machine with an internet browser and transfer the OAuth authentication values after you authenticate through the usual browser-based flow.

After you execute either Option 1 or Option 2, configure the driver to automatically refresh the access token on the headless machine.

Option 1: Obtaining and Exchanging a Verifier Code

To obtain a verifier code, you must authenticate at the OAuth authorization URL. Do the following:

  1. Authenticate from the machine with an internet browser, and obtain the OAuthVerifier connection property.

    Set the following properties:

    • InitiateOAuth = OFF.
    • OAuthClientId = the client Id assigned when you registered your application.
    • OAuthClientSecret = the client secret assigned when you registered your application.

  2. Call the GetOAuthAuthorizationURL stored procedure. The stored procedure returns the CallbackURL established when the custom OAuth application was registered. (See Creating a Custom OAuth Application.)

    Copy this URL and paste it into a new browser tab.

  3. Log in and grant permissions to the cmdlet. The OAuth application redirects you the redirect URI, with a parameter called code appended. Note the value of this parameter; you will need it later, to configure the OAuthVerifier connection property.

  4. Exchange the OAuth verifier code for OAuth refresh and access tokens. On the headless machine, set the following connection properties to obtain the OAuth authentication values:

    • InitiateOAuth = REFRESH.
    • OAuthVerifier = the noted verifier code (the value of the code parameter in the redirect URI).
    • OAuthSettingsLocation = persist the encrypted OAuth authentication values to the specified file.
    • OAuthClientId = the client Id in your custom OAuth application settings.
    • OAuthClientSecret = the client secret in the custom OAuth application settings.

  5. Test the connection to generate the OAuth settings file.

  6. After you re-set the following properties, you are ready to connect:

    • InitiateOAuth = REFRESH.
    • OAuthSettingsLocation = the file containing the encrypted OAuth authentication values. To enable the automatic refreshing of the access token, be sure that this file gives read and write permissions to the cmdlet.
    • OAuthClientId = the client Id assigned when you registered your application.
    • OAuthClientSecret = the client secret assigned when you registered your application.

Option 2: Transferring OAuth Settings

Prior to connecting on a headless machine, you must install and create a connection with the driver on a device that supports an internet browser. Set the connection properties as described above in "Desktop Applications".

After completing the instructions in "Desktop Applications", the resulting authentication values are encrypted and written to the path specified by OAuthSettingsLocation. The default filename is OAuthSettings.txt.

Test the connection to generate the OAuth settings file, then copy the OAuth settings file to your headless machine.

To connect to data via the headless machine, set the following connection properties:

  • InitiateOAuth = REFRESH
  • OAuthSettingsLocation = the path to the OAuth settings file you copied from the machine with the browser. To enable automatic refreshing of the access token, ensure that this file gives read and write permissions to the cmdlet.
  • OAuthClientId = the client Id assigned when you registered your custom OAuth application.
  • OAuthClientSecret = the client secret assigned when you registered your custom OAuth application.

Retrieving Data

The Select-Trello cmdlet provides a native PowerShell interface for retrieving data: 

$results = Select-Trello -Connection $conn -Table "Cards" -Columns @("Name, ListId") -Where "CardId='614060b2c37da423f30dc7d6'"
The Invoke-Trello cmdlet provides an SQL interface. This cmdlet can be used to execute an SQL query via the Query parameter.

Piping Cmdlet Output

The cmdlets return row objects to the pipeline one row at a time. The following line exports results to a CSV file: 

Select-Trello -Connection $conn -Table Cards -Where "CardId = '614060b2c37da423f30dc7d6'" | Select -Property * -ExcludeProperty Connection,Table,Columns | Export-Csv -Path c:\myCardsData.csv -NoTypeInformation

You will notice that we piped the results from Select-Trello into a Select-Object cmdlet and excluded some properties before piping them into an Export-CSV cmdlet. We do this because the CData Cmdlets append Connection, Table, and Columns information onto each row object in the result set, and we do not necessarily want that information in our CSV file.

However, this makes it easy to pipe the output of one cmdlet to another. The following is an example of converting a result set to JSON: 

 
PS C:\> $conn  = Connect-Trello -APIKey "myApiKey" -Token="myGeneratedToken"
PS C:\> $row = Select-Trello -Connection $conn -Table "Cards" -Columns (Name, ListId) -Where "CardId = '614060b2c37da423f30dc7d6'" | select -first 1
PS C:\> $row | ConvertTo-Json
{
  "Connection":  {

  },
  "Table":  "Cards",
  "Columns":  [

  ],
  "Name":  "MyName",
  "ListId":  "MyListId"
}

Deleting Data

The following line deletes any records that match the criteria: 

Select-Trello -Connection $conn -Table Cards -Where "CardId = '614060b2c37da423f30dc7d6'" | Remove-Trello

Modifying Data

The cmdlets make data transformation easy as well as data cleansing. The following example loads data from a CSV file into Trello, checking first whether a record already exists and needs to be updated instead of inserted. 

Import-Csv -Path C:\MyCardsUpdates.csv | %{
  $record = Select-Trello -Connection $conn -Table Cards -Where ("CardId = `'"+$_.CardId+"`'")
  if($record){
    Update-Trello -Connection $conn -Table Cards -Columns @("Name","ListId") -Values @($_.Name, $_.ListId) -Where "CardId  = `'$_.CardId`'"
  }else{
    Add-Trello -Connection $conn -Table Cards -Columns @("Name","ListId") -Values @($_.Name, $_.ListId)
  }
}

Copyright (c) 2024 CData Software, Inc. - All rights reserved.
Build 24.0.9060