Lookups
The Project Structure docs explains how modules and stacks are generally defined in the app folder. Modules and stacks can also be defined in the vendor folder also.
Terraspace commands like terraspace build and terraspace up search for modules in the app/modules and vendor/modules folders. It similar to how LOAD_PATH works. This allows 3rd party modules to be neatly organized.
Example
Here’s an example with some modules in the vendor folder.
├── app
│ └── modules
│ └── instance
└── vendor
└── modules
├── database
└── network
In this case, there are database and network 3rd parties modules. There’s also a normal project module called instance.
Precedence
When there are 2 modules with the same name in both the app/modules and vendor/modules folder, the module in the app/modules folder takes higher precedence and wins.
Eventually, terraspace builds all the modules to the .terraspace-cache folder. Example:
.terraspace-cache/us-west-2/dev/modules/database
.terraspace-cache/us-west-2/dev/modules/instance
.terraspace-cache/us-west-2/dev/modules/network
terraspace bundle
The vendor additional lookup location can be particularly useful with modules declared in a Terrafile. You can add modules to your Terrafile definition and download them to the vendor/modules folder with:
terraspace bundle
For more info, see the Terrafile docs.