Trello Channel

See the Channel Catalog to see which Plans have access to this channel.

Trello is a web-based, Kanban-style, list-making application. Trello is a collaboration tool that organizes your projects into boards. Trello brings a visual perspective to projects, allowing you to see the status of who’s working on what, and what needs to get done in a single glance.

How to Connect

1. On the My pipelines page, click Create Pipelines. 
   
2. Search for the first step for your new pipeline. You can always add more steps later.
3. To use the legacy builder, click the Pipeline Designer toggle to use the legacy version of the pipeline builder.
   

For more information about connections, see How to connect to a channel.

Connect to Trello

1. On the right side of the page, choose All to list all channels enabled for your realm. Make sure Trello is enabled.
2. Expand Trello and click Connect to Trello.​ You will see a dialog form that asks you to authorize Pipelines. Click on Connect to Trello.
   
3. You will be prompted with the following screen. Trello will ask you if you grant QuickBase access to your profile. Click on Log In.
   
4. After that you will be redirected to the Trello Login page and asked to log in with email and password or credentials using other platforms.
   

How to reconnect

You may need to reconnect your account to a channel. Reasons may be (but not limited to):

• If you need to connect a different account.
• Authorization updates, such as a changed password.
• Editing the access rights that Pipelines has to the channel.

To reconnect:

1. Select a pipeline that already has this channel in it.
2. Open a step that contains this channel.
3. Under account, select Connect (or reconnect) and follow the process above, How to connect.
   

Steps

The steps you can use with Trello fall under five categories: Board, List, Card, Comments, and Attachments.

Note: You cannot use jinja expressions in trigger conditions unless explicitly specified as possible.

Limits

Trello limits the number of objects that can exist on a board or card. The limits for each type of object and whether they are limited at the card or board level are available via the cards and boards API resources.

Notice: Limits may vary by boards and accounts. You should adjust your application to handle the responses and their values appropriately.

Board-level Limits

There are a number of objects in Trello that are limited at the board level. For instance, to see the limits that exist on a board, we can make the following request:

curl https://api.trello.com/1/boards/552595baa7b650edb7a0f8ff/?fields=limits

​The following enumerated limits for cards can be taken from the returned response:

The first set of values for the key openPerBoard indicates that Trello allows for 5000 open cards to exist per a board and that the Trello clients (web, mobile, desktop) will begin to warn users when they have 4500 cards open on a bard. The second object for key totalPerBoard means that Trello allows for 2000000 total cards (open or closed) to be on a board and that the clients will begin warning when there are 1800000.

The disableAt limit is the count at which the clients will no longer allow users to add objects of that kind. ​The status field indicates whether the board is in violation of the current limits. In this case, the board hasn't exceeded these limits. When a board has exceeded one of the types of limits, the status will change and a count field and value appear.

For example, if our board were to have more cards than allowed for by the disableAt the limits would be updated:

Similarly, if the count is above the warnAt limit, the status will change to warn.

Additionally, there is a maximum number for each limit above which the API will return an error if more objects are attempted to be added. The status of objects that exceeded the limits prior to their creation is maxExceeded.

Card-level Limits

We can also see limits that are specific to cards by including limits as a value for the fields query parameter when making requests to card resources:

curl https://trello.com/1/boards/552595baa7b650edb7a0f8ff/cards/?fields=limits&limit=1

The received response will look similar to the boards-level limits. The card-level limits function the exact same as the board-level limits outlined above.

Webhooks and Limits

​In addition to limiting the number of different types of objects that can exist on a board or card, Trello disallows creating new webhooks on objects that have exceeded their limits.

Attempting to create a webhook on an object that has exceeded its limits will result in the following error message: HTTP/1.1 500 Model exceeds limits​. Webhooks that exist on models that have a limit status of maxExceeded will be deleted.

API Rate Limits

To help prevent strain on Trello’s servers, Trello’s API imposes rate limits per API key for all issued tokens. There is a limit of 300 requests per 10 seconds for each API key and no more than 100 requests per 10 second interval for each token. If a request exceeds the limit, Trello will return a 429 error.

For more detailed information about Trello restrictions and limitations click here.

Use case examples

The following are some example of using the Trello channel.

In this example, a Quickbase app that contains information about tasks that need to be done. It would be convenient every time we update a card in Trello to transfer that information to the Quickbase app. If the card is not in the QB table a new record would be created, otherwise the card information would be updated. The following example shows the steps to create this pipeline.

1. First you must create a Quickbase application that has a table containing records with the following fields:
   

2. Create a new pipeline and connect to your Trello and Quickbase profiles.

3. The first step to be added is Card Updated from Trello. This step would trigger whenever someone updates a card in the specified board.
   

4. The second step to be added is Search Records from Quickbase. Fill in the required information and add a condition to search by ID, which is taken from the trigger step.
   

5. In the Loop statement after the search step add a new Update Record step from Quickbase and fill in the information from the trigger step.
   

6. Now, click Insert a Condition to add an IF statement to check if the search step has returned an empty list.
   

7. If the list is empty, then add a new Create Record step from Quickbase and fill in the information. The Else clause will remain empty.
   

8. After triggering the pipeline we see the following in our Activity log: