Redmine is an open-source project management/issue tracking system. I wanted to copy issues out of Redmine and import them into a Visual Studio Team Services project.

Extracting issues can be done by using the "CSV" link at the bottom of the Issues list for a project in Redmine. This CSV file doesn't contain absolutely everything for each issue (eg. attachments and custom data from any plugins). Another alternative would be to query the database directly, but that wasn't necessary for my scenario.

To migrate the data to VSTS you can use a simple PowerShell script, making use of the VSTS REST API.

You'll need to create a Personal Access Token. Be aware that all items will be created under the account linked to this token - there's no way that I'm aware of that you can set the "CreatedBy" field to point to another user.

Notice in the script how we handle different fields for different work items types (eg. Product Backlog Items use the 'Description' field, whereas Bugs use 'Repro Steps'), and for optional fields (eg. not all Redmine issues had the 'Assignee' field set).

The full set of fields (and which work item types they apply to) is documented here. If you have more fields in Redmine that can be mapped to ones in VSTS then go ahead and add them.