feat(index): Index module foundation (#9095)

**What**
Index module foundation

Co-authored-by: Carlos R. L. Rodrigues <37986729+carlos-r-l-rodrigues@users.noreply.github.com>

packages/modules/index/src/models/index-data.ts

@@ -0,0 +1,45 @@
+import {
+  Cascade,
+  Collection,
+  Entity,
+  Index,
+  ManyToMany,
+  OptionalProps,
+  PrimaryKey,
+  PrimaryKeyType,
+  Property,
+} from "@mikro-orm/core"
+import { IndexRelation } from "./index-relation"
+
+type OptionalRelations = "parents"
+
+@Entity({
+  tableName: "index_data",
+})
+export class IndexData {
+  [OptionalProps]: OptionalRelations
+
+  @PrimaryKey({ columnType: "text" })
+  @Index({ name: "IDX_index_data_id" })
+  id!: string
+
+  @PrimaryKey({ columnType: "text" })
+  @Index({ name: "IDX_index_data_name" })
+  name: string;
+
+  [PrimaryKeyType]?: [string, string]
+
+  @Index({ name: "IDX_index_data_gin", type: "GIN" })
+  @Property({ columnType: "jsonb", default: "{}" })
+  data: Record<string, unknown>
+
+  @ManyToMany({
+    owner: true,
+    entity: () => IndexData,
+    pivotEntity: () => IndexRelation,
+    cascade: [Cascade.REMOVE],
+    inverseJoinColumns: ["parent_id", "parent_name"],
+    joinColumns: ["child_id", "child_name"],
+  })
+  parents = new Collection<IndexData>(this)
+}

packages/modules/index/src/models/index-relation.ts

@@ -0,0 +1,64 @@
+import {
+  Entity,
+  Index,
+  ManyToOne,
+  OptionalProps,
+  PrimaryKey,
+  Property,
+  Ref,
+} from "@mikro-orm/core"
+import { IndexData } from "./index-data"
+
+type OptionalRelations =
+  | "parent"
+  | "child"
+  | "parent_id"
+  | "child_id"
+  | "parent_name"
+  | "child_name"
+
+@Entity({
+  tableName: "index_relation",
+})
+@Index({
+  name: "IDX_index_relation_child_id",
+  properties: ["child_id"],
+})
+export class IndexRelation {
+  [OptionalProps]: OptionalRelations
+
+  @PrimaryKey({ columnType: "integer", autoincrement: true })
+  id!: string
+
+  // if added as PK, BeforeCreate value isn't set
+  @Property({
+    columnType: "text",
+  })
+  pivot: string
+
+  @Property({ columnType: "text" })
+  parent_id?: string
+
+  @Property({ columnType: "text" })
+  parent_name?: string
+
+  @Property({ columnType: "text" })
+  child_id?: string
+
+  @Property({ columnType: "text" })
+  child_name?: string
+
+  @ManyToOne({
+    entity: () => IndexData,
+    onDelete: "cascade",
+    persist: false,
+  })
+  parent?: Ref<IndexData>
+
+  @ManyToOne({
+    entity: () => IndexData,
+    onDelete: "cascade",
+    persist: false,
+  })
+  child?: Ref<IndexData>
+}

packages/modules/index/src/models/index.ts

@@ -0,0 +1,2 @@
+export { IndexData } from "./index-data"
+export { IndexRelation } from "./index-relation"