upd README.md

README.md

@@ -1,2 +1,71 @@
 # repo
 
+This module is mainly an exercise with generics. Although it is a fully functional repository for any Go structs. 
+
+Might be useful for pet-projects and like. 
+
+Example usage.
+
+```go
+import (
+    "code.uint32.ru/tiny/repo"
+    _ "github.com/mattn/go-sqlite3"
+)
+
+type My struct {
+	A string
+	B int
+}
+
+func main() {
+    db, err := sql.Open("sqlite3", "test.db")
+    if err != nil {
+		panic(err)
+	}
+
+    defer db.Close()
+
+    ctx := context.Background()
+
+    // init repository for our type "My"
+    r, err := repo.OpenOrCreate[My](ctx, db, "my_test_table")
+    if err != nil {
+        panic(err)
+    }
+
+    first := &My{
+		A: "hello",
+		B: 42,
+	}
+
+	if err := r.Create(ctx, "first_record", first); err != nil {
+		panic(err)
+	}
+
+    duplicate, err = r.Read(ctx, "first_record")
+	if err != nil {
+		panic(err)
+	}
+
+    fmt.Printf("Type: %T, Value: %+v", duplicate)
+}
+```
+
+The interface is a plain CRUD.
+```go
+type Repo[T any] interface {
+	// Create inserts object into repository table. If id already exists
+	// in the database it is an error.
+	Create(ctx context.Context, id string, v *T) error
+	// Read returns object with specified id or ErrNotFound
+	Read(ctx context.Context, id string) (*T, error)
+	// Update updates object with id.
+	Update(ctx context.Context, id string, v *T) error
+	// Delete performs soft-delete (actually marks object as unavailable).
+	Delete(ctx context.Context, id string) error
+	// Purge actually deletes database record with id.
+	Purge(ctx context.Context, id string) error
+}
+```
+
+

test/example.go

@@ -0,0 +1,49 @@
+package main
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+
+	"code.uint32.ru/tiny/repo"
+	_ "github.com/mattn/go-sqlite3"
+)
+
+type My struct {
+	A string
+	B int
+}
+
+func main() {
+	db, err := sql.Open("sqlite3", "test.db")
+	if err != nil {
+		panic(err)
+	}
+
+	defer db.Close()
+
+	ctx := context.Background()
+
+	// init repository for our type "My"
+	r, err := repo.OpenOrCreate[My](ctx, db, "my_test_table")
+	if err != nil {
+		panic(err)
+	}
+
+	first := &My{
+		A: "hello",
+		B: 42,
+	}
+
+	if err := r.Create(ctx, "first_record", first); err != nil {
+		panic(err)
+	}
+
+	duplicate, err := r.Read(ctx, "first_record")
+	if err != nil {
+		panic(err)
+	}
+
+	// prints Type: *main.My, Value: &{A:hello B:42}
+	fmt.Printf("Type: %T, Value: %+v\n", duplicate, duplicate)
+}

test/repo_test.go

@@ -1,4 +1,4 @@
-package repo_test
+package main
 
 import (
 	"context"
@@ -15,11 +15,6 @@ import (
 	"code.uint32.ru/tiny/repo"
 )
 
-type My struct {
-	A string
-	B int
-}
-
 func TestSqlite3(t *testing.T) {
 	db, err := sql.Open("sqlite3", "test.db")
 	if err != nil {