Update README.md

README.md

@@ -1,4 +1,4 @@
-# yowrap
+# 🌮 yowrap 🌮
 
 [![GoDoc](https://img.shields.io/static/v1?label=godoc&message=reference&color=blue)](https://pkg.go.dev/github.com/jferrl/yowrap)
 [![Test Status](https://github.com/jferrl/yowrap/workflows/tests/badge.svg)](https://github.com/jferrl/yowrap/actions?query=workflow%3Atests)
@@ -7,5 +7,157 @@
 
 Lightweight Go package designed to effortlessly wrap the [Yo](https://github.com/cloudspannerecosystem/yo) package for enhanced functionality.
 
+## Context
 
+[Yo](https://github.com/cloudspannerecosystem/yo) is a command-line tool that generates Go code from SQL DDL files. The generated code is used to interact with Google Cloud Spanner databases, representing the table and a set of methods to interact with the table.
 
+Yo is a great tool to generate the boilerplate code needed to interact with a Google Cloud Spanner database. However, the generated code is not intended to be modified by the user, as it is overwritten every time the `yo` tool is executed. This package provides a way to extend a model with custom methods, without modifying the generated code.
+
+The main idea of this pkg is extending the `yo` generated code functionality in order to create a more capable model.
+
+This package is designed to be used in conjunction with the `yo` tool, not as a replacement.
+
+See [Yo](https://github.com/cloudspannerecosystem/yo) for more information about the `yo` tool.
+
+## Features
+
+- **Commit transaction**: This feature allows the client to commit a model transaction directly from the model instance without using the spanner.Mutation outside the model. Now, the model has the responsibility of writing the changes to the database.
+- **Custom model hooks**: This feature allows the client to define custom hooks that will be executed before or after a specific method is called. This is useful for adding custom logic to the model methods.
+- **Inheric model methods**: All the method signatures from the generated code are inherited by the model. This allows the client to call the generated methods directly from the model instance.
+
+## Usage
+
+Use `yowrap` as a wrapper for the generated model but committing the transaction outside the model. This mantains the ability to use the generated methods-
+
+```go
+package main
+
+import (
+    "context"
+    "fmt"
+    "log"
+
+    "cloud.google.com/go/spanner"
+    "github.com/jferrl/yowrap"
+)
+
+
+func main() {
+    spannerClient, err := spanner.NewClient(ctx, "projects/my-project/instances/my-instance/databases/my-database")
+    if err != nil {
+        log.Fatalf("Failed to create a Spanner client: %v", err)
+    }
+    defer spannerClient.Close()
+
+    // Go struct generated by the yo tool
+    user := &User{
+        ID:    1,
+        Name:  "John Doe",
+        Email: " [email protected]",
+    }
+
+    // Create a new user model
+    user := yowrap.NewModel(user)
+
+    mut := user.Insert(ctx)
+
+
+
+    _, err = spannerClient.Apply(ctx, []*spanner.Mutation{mut})
+    if err != nil {
+        log.Fatalf("Failed to apply the mutation: %v", err)
+    }
+}
+```
+
+Use `yowrap` as a wrapper for the generated model and commit the transaction directly from the model.
+
+```go
+
+package main
+
+import (
+    "context"
+    "fmt"
+    "log"
+
+    "cloud.google.com/go/spanner"
+    "github.com/jferrl/yowrap"
+)
+
+func main() {
+    spannerClient, err := spanner.NewClient(ctx, "projects/my-project/instances/my-instance/databases/my-database")
+    if err != nil {
+        log.Fatalf("Failed to create a Spanner client: %v", err)
+    }
+    defer spannerClient.Close()
+
+    // Go struct generated by the yo tool
+    user := &User{
+        ID:    1,
+        Name:  "John Doe",
+        Email: " [email protected]",
+    }
+
+    // Create a new user model
+    user := yowrap.NewModel(user, yowrap.WithSpannerClientOption(spannerClient))
+
+    // Commit the transaction
+    _, err = user.Apply(ctx, yowrap.Insert)
+    if err != nil {
+        log.Fatalf("Failed to insert and commit the user: %v", err)
+    }
+}
+```
+
+Use `yowrap` with a custom hook.
+
+```go
+
+package main
+
+import (
+    "context"
+    "fmt"
+    "log"
+
+    "cloud.google.com/go/spanner"
+    "github.com/jferrl/yowrap"
+)
+
+func main() {
+    spannerClient, err := spanner.NewClient(ctx, "projects/my-project/instances/my-instance/databases/my-database")
+    if err != nil {
+        log.Fatalf("Failed to create a Spanner client: %v", err)
+    }
+    defer spannerClient.Close()
+
+    // Go struct generated by the yo tool
+    user := &User{
+        ID:    1,
+        Name:  "John Doe",
+        Email: " [email protected]",
+    }
+
+    // Create a new user model
+    user := yowrap.NewModel(user, yowrap.WithSpannerClientOption(spannerClient))
+
+    // Add a custom hook
+    user.On(yowrap.BeforeInsert, func(_ context.Context, m *yowrap.Model[*user.User], _ *spanner.ReadWriteTransaction) error {
+        log.Println("Before insert")
+        return nil
+    })
+
+    // Commit the transaction
+    _, err = user.Apply(ctx, yowrap.Insert)
+    if err != nil {
+        log.Fatalf("Failed to insert and commit the user: %v", err)
+    }
+}
+```
+
+## License
+
+Copyright 2024, jferrl
+
+yowrap is released under the MIT license.