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Announcing the "Schema Import Initiative" and protoc-gen-ent

Migrating to a new ORM is not an easy process, and the transition cost can be prohibitive to many organizations. As much as we developers are enamoured by "Shiny New Things", the truth is that we rarely get a chance to work on a truly "green-field" project. Most of our careers, we operate in contexts where many technical and business constraints (a.k.a legacy systems) dictate and limit our options for moving forward. Developers of new technologies that want to succeed must offer interoperability capability and integration paths to help organizations seamlessly transition to a new way of solving an existing problem.

To help lower the cost of transitioning to Ent (or simply experimenting with it), we have started the "Schema Import Initiative" to help support many use cases for generating Ent schemas from external resources. The centrepiece of this effort is the schemast package (source code, docs) which enables developers to easily write programs that generate and manipulate Ent schemas. Using this package, developers can program in a high-level API, relieving them from worrying about code parsing and AST manipulations.

Protobuf Import Support#

The first project to use this new API, is protoc-gen-ent, a protoc plugin to generate Ent schemas from .proto files (docs). Organizations that have existing schemas defined in Protobuf can use this tool to generate Ent code automatically. For example, taking a simple message definition:

syntax = "proto3";
package entpb;
option go_package = "github.com/yourorg/project/ent/proto/entpb";
message User {
string name = 1;
string email_address = 2;
}

And setting the ent.schema.gen option to true:

syntax = "proto3";
package entpb;
+import "options/opts.proto";
option go_package = "github.com/yourorg/project/ent/proto/entpb";
message User {
+ option (ent.schema).gen = true; // <-- tell protoc-gen-ent you want to generate a schema from this message
string name = 1;
string email_address = 2;
}

Developers can invoke the standard protoc (protobuf compiler) command to use this plugin:

protoc -I=proto/ --ent_out=. --ent_opt=schemadir=./schema proto/entpb/user.proto

To generate Ent schemas from these definitions:

package schema
import (
"entgo.io/ent"
"entgo.io/ent/schema/field"
)
type User struct {
ent.Schema
}
func (User) Fields() []ent.Field {
return []ent.Field{field.String("name"), field.String("email_address")}
}
func (User) Edges() []ent.Edge {
return nil
}

To start using protoc-gen-ent today, and read about all of the different configuration options, head over to the documentation!

Join the Schema Import Initiative#

Do you have schemas defined elsewhere that you would like to automatically import in to Ent? With the schemast package, it is easier than ever to write the tool that you need to do that. Not sure how to start? Want to collaborate with the community in planning and building out your idea? Reach out to our great community via our Slack channel or start a discussion on GitHub!

For more Ent news and updates: