Merge pull request #15 from jensteichert/f/custom-ids

support custom doc ids

README.md

@@ -1,5 +1,5 @@
 # Colt
-The mongodb ODM for Go i've always wanted
+The [MongoDB](https://www.mongodb.com) ODM for [Go](https://go.dev) i've always wanted.
 
 ![Build & Tests](https://github.com/jensteichert/webvitals_exporter/workflows/Build/badge.svg)
 ![CodeQL](https://github.com/jensteichert/colt/workflows/CodeQL/badge.svg)
@@ -8,7 +8,11 @@ The mongodb ODM for Go i've always wanted
 [![Go Report Card](https://goreportcard.com/badge/github.com/jensteichert/colt)](https://goreportcard.com/report/github.com/jensteichert/colt)
 [![Coverage Status](https://coveralls.io/repos/github/jensteichert/colt/badge.svg?branch=main)](https://coveralls.io/github/jensteichert/colt?branch=main)
 
-Colt leverages Generics to provide type-safe methods and decoding of documents. It therefor requires [Go 1.18+](https://tip.golang.org/doc/go1.18). 
+Colt is a wrapper around the official [mongo-go-driver](https://github.com/mongodb/mongo-go-driver).
+
+### Requirements
+- [Go 1.18](https://tip.golang.org/doc/go1.18) or higher. Colt leverages Generics to provide type-safe methods and decoding of documents.
+
 ### Installation
 To install Colt, use `go get`:
 ```
@@ -81,13 +85,22 @@ func(t *Todo) BeforeUpdate() error {
 }
 ```
 
+#### ``NewID`` Hook
+Can be used to generate custom ids for documents within a collection
+```golang
+func(t *Todo) BeforeUpdate() error {
+	t.DocWithTimestamps.BeforeUpdate()
+
+        // Do something with t here
+	return nil
+}
+```
 
 ### ToDo
 - [x] CRUD
 - [x] Hooks
 - [x] Disconnect
 - [ ] Context
-- [ ] Aggregations
 - [ ] Transactions
 
 

collection.go

@@ -14,7 +14,7 @@ type Collection[T Document] struct {
 
 func (repo *Collection[T]) Insert(model T) (T, error) {
 	if model.GetID() == "" {
-		model.SetID(repo.NewId().Hex())
+		model.SetID(model.NewID())
 	}
 
 	if hook, ok := any(model).(BeforeInsertHook); ok {

document.go

@@ -1,17 +1,26 @@
 package colt
 
-import "time"
+import (
+	"go.mongodb.org/mongo-driver/bson/primitive"
+	"time"
+)
 
 type Document interface {
 	SetID(id string)
 	GetID() string
+
+	NewID() string
 	//CastID(id interface{}) (interface{}, error)
 }
 
 type Doc struct {
 	ID    string `bson:"_id,omitempty" json:"_id,omitempty"`
 }
 
+func (doc *Doc) NewID() string {
+	return primitive.NewObjectID().Hex()
+}
+
 func (doc *Doc) SetID(id string) {
 	doc.ID = id
 }

document_test.go

@@ -2,6 +2,8 @@ package colt
 
 import (
 	"github.com/stretchr/testify/assert"
+	"go.mongodb.org/mongo-driver/bson/primitive"
+	"strings"
 	"testing"
 )
 
@@ -24,4 +26,28 @@ func TestCDocument_GetID(t *testing.T) {
 	doc.SetID("638cda03871d719a9020c855")
 
 	assert.Equal(t, doc.ID, "638cda03871d719a9020c855")
+}
+
+func TestCDocument_NewID(t *testing.T) {
+	doc := todoWithCustomId{}
+	assert.Empty(t, doc.GetID())
+
+	assert.NotEmpty(t, doc.NewID())
+}
+
+type todoWithCustomId struct {
+	Doc   `bson:",inline"`
+	Title string `bson:"title" json:"title"`
+}
+
+func (t *todoWithCustomId) NewID() string {
+	return "td_" + primitive.NewObjectID().Hex()
+}
+
+func TestCDocument_NewID_Custom(t *testing.T) {
+	doc := todoWithCustomId{}
+	assert.Empty(t, doc.GetID())
+
+	assert.NotEmpty(t, doc.NewID())
+	assert.True(t, strings.HasPrefix(doc.NewID(), "td_"))
 }