Trello to Snowflake

This page provides you with instructions on how to extract data from Trello and load it into Snowflake. (If this manual process sounds onerous, check out Stitch, which can do all the heavy lifting for you in just a few clicks.)

What is Trello?

Trello is a collaboration tool that organizes projects into boards, each of which can be filled with lists of notes that outline tasks for a team, complete with photos, documents, and other attachments. It includes tools to comment and collaborate among teammates. You can use it as a web-based project management application.

What is Snowflake?

Snowflake is a cloud-based data warehouse that's fast, flexible, and easy to work with. It runs on Amazon Web Services EC2 and S3 instances, and separates compute and storage resources, enabling users to scale the two independently and pay only for resources used. Snowflake can natively load and optimize both structured and semi-structured data and make it available via SQL. It provides native support for JSON, Avro, XML, and Parquet data, and can provide access to the same data for multiple workgroups or workloads simultaneously with no contention roadblocks or performance degradation.

Getting data out of Trello

To claim your data from Trello, you can extract it from Trello's servers using the Trello API, a REST API that exposes endpoints that provide information on boards, lists, cards, and actions. For instance, to get data about a list, you might run /lists/[id].

Sample Trello data

The Trello API returns JSON-formatted data. Here's an example of the kind of response you might see when querying for the details of a list.

[{
    "id": "4efe314cc72846af4e00008a",
    "data": {
        "list": {
            "id": "4eea4ffc91e31d174600004a",
            "name": "To Do Soon"
        },
        "board": {
            "id": "4eea4ffc91e31d1746000046",
            "name": "Example Board"
        },
        "old": {
            "name": "To Do Later"
        }
    },
    "date": "2017-12-30T21:46:52.874Z",
    "idMemberCreator": "4ee7deffe582acdec80000ac",
    "type": "updateList",
    "memberCreator": {
        "id": "4ee7deffe582acdec80000ac",
        "avatarHash": null,
        "fullName": "Joe Tester",
        "initials": "JT",
        "username": "joetester"
    }
}, {
    "id": "4efe3147c72846af4e00006d",
    "data": {
        "list": {
            "id": "4eea4ffc91e31d174600004a",
            "name": "To Do Later"
        },
        "board": {
            "id": "4eea4ffc91e31d1746000046",
            "name": "Example Board"
        },
        "old": {
            "name": "To Do Eventually"
        }
    },
    "date": "2017-12-30T21:46:47.843Z",
    "idMemberCreator": "4ee7deffe582acdec80000ac",
    "type": "updateList",
    "memberCreator": {
        "id": "4ee7deffe582acdec80000ac",
        "avatarHash": null,
        "fullName": "Joe Tester",
        "initials": "JT",
        "username": "joetester"
    }
}]

Preparing Trello data

This part can get tricky: You need to parse the JSON in the API response and map each field to a corresponding table in the destination database. You'll need a solid handle on the datatypes for each endpoint. The Stitch Trello Docs can give you a sense of what datatypes will come through the API.

Preparing data for Snowflake

You may need to prepare your data before loading it. Check Snowflake's supported data types and make sure that your data maps neatly to them.

Note that you won't need to define a schema in advance when loading JSON or XML data into Snowflake.

Loading data into Snowflake

Snowflake's documentation outlines a Data Loading Overview that can lead you through the task of loading your data. If you're not loading a lot of data, Snowflake's data loading wizard may be helpful, but for many organizations, its limitations make it unacceptable. Instead, you can:

  • Use the PUT command to stage files.
  • Use the COPY INTO table command to load prepared data into an awaiting table.

You can copy data from your local drive or from Amazon S3. Snowflake lets you make a virtual warehouse that can power the insertion process.

Keeping Trello data up to date

At this point you've coded up a script or written a program to get the data you want and successfully moved it into your data warehouse. But how will you load new or updated data? It's not a good idea to replicate all of your data each time you have updated records. That process would be painfully slow and resource-intensive.

Instead, identify key fields that your script can use to bookmark its progression through the data and use to pick up where it left off as it looks for updated data. Auto-incrementing fields such as updated_at or created_at work best for this. When you've built in this functionality, you can set up your script as a cron job or continuous loop to get new data as it appears in Trello.

And remember, as with any code, once you write it, you have to maintain it. If Trello modifies its API, or the API sends a field with a datatype your code doesn't recognize, you may have to modify the script. If your users want slightly different information, you definitely will have to.

Other data warehouse options

Snowflake is great, but sometimes you need to optimize for different things when you're choosing a data warehouse. Some folks choose to go with Amazon Redshift, Google BigQuery, or PostgreSQL, which are RDBMSes that use similar SQL syntax, or Panoply, which works with Redshift instances. If you're interested in seeing the relevant steps for loading data into one of these platforms, check out To Redshift, To BigQuery, To Postgres, and To Panoply.

Easier and faster alternatives

If all this sounds a bit overwhelming, don’t be alarmed. If you have all the skills necessary to go through this process, chances are building and maintaining a script like this isn’t a very high-leverage use of your time.

Thankfully, products like Stitch were built to solve this problem automatically. With just a few clicks, Stitch starts extracting your Trello data via the API, structuring it in a way that is optimized for analysis, and inserting that data into your Snowflake data warehouse.