metadata.md

Provider Metadata

Bridged providers may need to persist information between different invocations of make tfgen, or between tfgen time and normal runtime. The bridge provides a mechanism to do that: metadata.

Provider metadata is required for PF based providers, muxed providers and AutoAliasing.

Setup

Adding provider metadata has three steps.

1. Creating the metadata file.
2. Embedding the metadata file.
3. Giving ProviderInfo a reference to the metadata file.

Creating the metadata file

The bridge expects the metadata file to live next to schema.json at cmd/pulumi-resource-${PROVIDER_NAME}/bridge-metadata.json (where ${PROVIDER_NAME} is replaced with the name of your provider). To bootstrap the file, the metadata file should be an empty JSON file.

To create the metadata file, run:

echo {} > cmd/pulumi-resource-${PROVIDER_NAME}/bridge-metadata.json

Embedding the metadata file

The bridge uses go:embed to access bridge-metadata.json at runtime. To embed a bridge-metadata.json, add _ "embed" to the imports section of resources.go:

import (
	_ "embed"

    ...
)

The _ in _ "embed" tells Go that you don't need to use any items from "embed", just to import the module.

Finally, we need to link the file to a variable so the Go compiler includes it during builds:

//go:embed cmd/pulumi-resource-${PROVIDER_NAME}/bridge-metadata.json
var metadata []byte

Giving ProviderInfo a reference to the metadata file

Now that bridge-metadata.json is embedded as the metadata variable, we need to give the returned tfbridge.ProviderInfo access. We do that by setting the MetadataInfo field on tfbridge.ProviderInfo:

import "github.com/pulumi/pulumi-terraform-bridge/v3/pkg/tfbridge"

func Provider() tfbridge.ProviderInfo {
	info := tfbridge.ProviderInfo{
    	MetadataInfo: tfbridge.NewProviderMetadata(metadata),
        ...
    }

    ...

	return info
}