Terraform 0.13 has an entirely new provider installer that allows for greater control over individual provider installation methods. The breaking change is a new, required, subdirectory hierarchy for provider binaries.

The key differences between Terraform v0.12 and v0.13 are the directory hierarchy. Terraform v0.12 would look for a provider binary under the following directories:

• $PATH/wherever the terraform executable lives

The following command-line options are available to override the default search and installation behavior:

• -plugin-dir: disables registry lookup; only search that directory

• -plugin-cache-dir: does not change search paths; installs providers into the specified directory

Install from registry if not found

A major implication of the provider source work is that terraform can no longer assume that provider types are unique: a user could have multiple provides with the same type in a given configuration. To support this, terraform now requires the all provider binaries are in a specific directory hierarchy corresponding with the source:

$BASEDIR/$SOURCEHOST/$NAMESPACE/$TYPE/$VERSION/$OS_$ARCH/

1. Filesystem
2. Terraform Registry

• terraform.d/plugins in the current working directory (documented in terraform-bundle as a place to put plugins as a way to include them in bundles uploaded to Terraform Cloud)

OS-specific paths:

• Windows: %APPDATA%/HashiCorp/Terraform/plugins
• Mac OS X: ~/Library/Application Support/io.terraform/plugins and /Library/Application Support/io.terraform/plugins
• Linux and other Unix-like systems: Terraform implements the XDG Base Directory specification and appends terraform/plugins to all of the specified data directories. Without any XDG environment variables set, Terraform will use ~/.local/share/terraform/plugins, /usr/local/share/terraform/plugins, and /usr/share/terraform/plugins.

Maybe $HOME/.terraform.d/plugins?

Same use-facing behavior as 0.12: terraform queries the registry to find providers. If a provider is found in one of the search paths, terraform will not query the registry for that provider (TODO: check that -upgrade overrides that as expected).

-plugin-dir: only that directory will be searched (no registry lookup) Q: does this override CLI config?

We've added a CLI configuration setting to let users declare plugin search locations for all configurations on a given workstation.

1. filesystem_mirror
2. direct
3. network_mirror [targeting future release]

Default: .terraform/plugins/$SOURCEHOST/$NAMESPACE/$TYPE/$VERSION/$OS_$ARCH/ Options:

• -plugin-cache-dir command-line flag: does not change search behavior, just install: plugins will be downloaded into, and installed from, the cache dir
• plugin_cache_dir CLI config setting: same as above.