activeso

README

ActiveSo

ActiveSo is a small active record-like persistence layer for Go structs backed by Turso.

Table of contents

• Quick start
• Mapping a model to SQL
• Constraint options
• API
• Browser example

Quick start

package main

import (
	"context"
	"database/sql"

	"github.com/sectionco/activeso"
	turso "turso.tech/database/tursogo"
)

type User struct {
	activeso.Record

	ID        string             `db:"id"`
	Email     string             `db:"email" activeso:"not_null,unique"`
	Embedding activeso.Vector32 `db:"embedding"`
}

func example(ctx context.Context) error {

	// Create a Turso connector and open a database/sql handle over it.
	connector, err := turso.NewConnector("app.db")
	if err != nil {
		return err
	}
	db := sql.OpenDB(connector)
	defer db.Close()

	// Initialize the User model.
	userModel := activeso.Model[User](db)

	// Optional: run during application setup to create or update the schema.
	if err := userModel.AutoMigrate(ctx); err != nil {
		return err
	}

	// Create a new User record.
	user, err := userModel.Create(ctx, User{Email: "hello@null.live"})
	if err != nil {
		return err
	}

	// Update the user's email.
	user.Email = "updated@null.live"
	if err := user.Save(ctx); err != nil {
		return err
	}

	// Delete the user.
	return user.Delete(ctx)
}

Model uses plural snake_case table names by default (User maps to users).

Implement TableName() string on a model for an explicit table name.

Run AutoMigrate(ctx) separately during application setup or deployment when you want ActiveSo to create the table, add missing nullable columns, and create tagged unique indexes; it is not required for normal model initialization or record operations.

Mapping a model to SQL

For example, the User model maps to the following Turso table.

type User struct {
	activeso.Record

	ID    string `db:"id"`
	Email string `db:"email" activeso:"not_null,unique"`
}

CREATE TABLE users (
	id TEXT PRIMARY KEY,
	email TEXT NOT NULL
);

CREATE UNIQUE INDEX activeso_7573657273_656d61696c_unique ON users (email);

Record holds ActiveSo's runtime persistence binding and is not a database column. The db tags select column names; without them, ActiveSo derives snake_case names from exported field names. The activeso:"not_null,unique" tag adds NOT NULL and a unique index when AutoMigrate(ctx) runs.

When loading a plain Go string, ActiveSo reads SQL NULL as "". This is the default: it lets a nullable string column added by AutoMigrate remain readable for pre-existing rows. A plain string write always stores text, so NULL and an empty string become indistinguishable after the value is loaded or saved.

Plain numeric and boolean fields also read NULL as their Go zero values (0, 0.0, and false) so rows created before an additive nullable migration remain readable. Use nullable database/sql value types when the distinction between NULL and a zero value matters.

ActiveSo supports sql.NullString as TEXT, sql.NullInt64 as INTEGER, sql.NullFloat64 as REAL, and sql.NullBool as INTEGER. Use sql.NullString when your application needs to preserve the distinction between a missing string and an empty string. Import database/sql and use it directly in the model; ActiveSo retains Valid when loading and saving:

type User struct {
	activeso.Record

	ID       string         `db:"id"`
	Nickname sql.NullString `db:"nickname"`
}

sql.NullString{Valid: false} represents SQL NULL; sql.NullString{String: "", Valid: true} represents an empty string.

Constraint options

Add comma-separated constraint options in an activeso struct tag:

type User struct {
	activeso.Record

	ID    string `db:"id"`
	Email string `db:"email" activeso:"not_null,unique"`
}

Option	AutoMigrate(ctx) behavior	Write behavior
not_null	Adds NOT NULL when creating a table. ActiveSo refuses to add a new required column to an existing table automatically.	Turso rejects NULL values.
unique	Creates a stable, unambiguous unique index for the table and column.	Create and Save check for an existing value first and return an error matching activeso.ErrUnique; the Turso index remains the concurrency-safe authority.
primary_key	Declares the field as the table primary key.	Selects the identity used by Find, Save, and Delete; the field must use a supported immutable scalar type.

If no field has primary_key, ActiveSo uses the field mapped to id. Exactly one primary key is required. Supported primary-key types are strings, booleans, signed integers, uint8, uint16, uint32, and floats. uint and uint64 are rejected because their full range cannot be represented by Turso's signed 64-bit INTEGER.

An unknown activeso constraint causes activeso.Model[T](db) to panic so schema mistakes are caught during setup.

API

Contents

• Model
• AutoMigrate
• Explicit migrations
• Create
• Find
• All
• Where
• OrderBy
• Limit
• Nearest
• First
• Bind
• Save
• Delete

Model

activeso.Model[T](db) creates the persistence model for your Go struct type. In this example, T is User, so activeso.Model[User](db) maps User values to the users table.

userModel := activeso.Model[User](db)

AutoMigrate

AutoMigrate(ctx) creates the table, adds missing nullable columns, and creates tagged unique indexes. Call it once during application setup or deployment, separately from normal record operations.

For an existing table, the model's ID column must be protected by a sole primary key or a single-column unique index. ActiveSo rejects composite primary keys that do not make the modeled ID independently unique, preventing Save and Delete from targeting multiple rows.

if err := userModel.AutoMigrate(ctx); err != nil {
	return err
}

Explicit migrations

AutoMigrate(ctx) is intentionally additive and safe: it never drops data, removes indexes, changes column types, or tightens existing constraints. Make destructive schema changes deliberately by first updating the model definition, then calling the matching operation during deployment.

Operation	Required model change	Effect
DropUnique(ctx, column)	Remove unique from the column's activeso tag.	Drops ActiveSo's named unique index.
DropColumn(ctx, column)	Remove the field from the model.	Rebuilds the table without the column.
ChangeColumnType(ctx, column)	Change the Go field's type.	Rebuilds the table using the newly inferred Turso column type.
SetNotNull(ctx, column)	Add not_null to the field's activeso tag.	Rebuilds the table with NOT NULL; it fails if any existing row contains NULL.

For example, to stop requiring unique emails, remove unique from the tag and run an explicit migration:

type User struct {
	activeso.Record

	ID    string `db:"id"`
	Email string `db:"email" activeso:"not_null"`
}

userModel := activeso.Model[User](db)
if err := userModel.DropUnique(ctx, "email"); err != nil {
	return err
}

Each column migration changes only its named target. Existing columns omitted from your Go struct, their data, and unrelated defaults, constraints, and indexes are preserved. For example, ChangeColumnType(ctx, "email") leaves an existing nickname column intact even if the struct no longer contains it. Removing a struct field alone never drops its database column; call DropColumn explicitly.

These operations rebuild the existing database schema inside a transaction. Unsupported dependencies cause an error, and failed migrations roll back. Remove indexes or constraints referencing a column before dropping it. Rebuilds currently reject dependent views/triggers, foreign keys involving the table, generated columns, autoincrement columns, primary-key type changes, and dropping inline primary-key columns; those require a dedicated migration. Explicit NULL expressions and fully shadowed row IDs can also require a dedicated migration. Run destructive migrations during a controlled deployment and back up production data first.

Create

Create(ctx, value) inserts value, generates an ID when its string ID field is empty, and returns the bound record.

user, err := userModel.Create(ctx, User{Email: "hello@null.live"})

Find

Find(ctx, id) loads the record with id. It returns activeso.ErrNotFound when no record exists.

user, err := userModel.Find(ctx, "8b291a21-e69b-47ed-a3e0-f43e7609b26d")

All

All(ctx) loads every record from the model's table.

users, err := userModel.All(ctx)

Where

Where(predicate, arguments...) starts a parameterized query. Pass one argument for each ? placeholder.

user, err := userModel.Where("email = ?", "hello@null.live").First(ctx)

Use multiple arguments for predicates with multiple placeholders:

excludedID := "8b291a21-e69b-47ed-a3e0-f43e7609b26d"
users, err := userModel.Where("email LIKE ? AND id <> ?", "%@null.live", excludedID).All(ctx)

OrderBy

OrderBy(expression) applies an ORDER BY expression to a query. Calling it after Nearest replaces the vector-distance ordering and discards that ordering's embedding argument.

users, err := userModel.Where("email LIKE ?", "%@null.live").
	OrderBy("email ASC").
	All(ctx)

Limit

Limit(limit) applies a positive maximum row count to a query.

users, err := userModel.Where("email LIKE ?", "%@null.live").
	Limit(10).
	All(ctx)

Nearest

Nearest(column, embedding) orders records by cosine distance from a Vector32 embedding in the specified Turso vector32 column. Lower distance is more similar; combine it with Limit to perform a nearest-neighbor search.

queryEmbedding := activeso.Vector32{0.12, -0.08, 0.63}
users, err := userModel.Nearest("embedding", queryEmbedding).Limit(10).All(ctx)

You can also use a vector as a Where argument when the predicate explicitly calls Turso's vector32(?) function:

queryEmbedding := activeso.Vector32{0.12, -0.08, 0.63}
users, err := userModel.Where(
	"vector_distance_cos(embedding, vector32(?)) < ?",
	queryEmbedding,
	0.2,
).All(ctx)

First

First(ctx) loads the first matching query result. It returns activeso.ErrNotFound when no record matches.

user, err := userModel.Where("email LIKE ?", "%@null.live").
	OrderBy("email ASC").
	First(ctx)

Bind

Bind(value) attaches persistence behavior to an existing record pointer, such as one loaded outside ActiveSo.

externalUser := &User{ID: "8b291a21-e69b-47ed-a3e0-f43e7609b26d", Email: "hello@null.live"}
user, err := userModel.Bind(externalUser)

Save

Save(ctx) updates all persisted fields except the primary key. It is available on records returned by Create, Find, query methods, or Bind.

A record's ID is captured when it becomes bound and cannot be changed. If you modify it, Save and Delete return activeso.ErrIDChanged; create a new record when you need a new identity.

user.Email = "updated@null.live"
err := user.Save(ctx)

Delete

Delete(ctx) deletes a bound record by primary key.

err := user.Delete(ctx)

Browser example

The example/ directory contains a small Echo v5 server with a single HTML page for creating, editing, and deleting users. It creates a local activeso-example.db file and listens on http://localhost:8080.

go -C example run .

Documentation

Index

• Variables
• func Model[T any](db *sql.DB) *model[T]
• type Record
  • func (record *Record) Delete(ctx context.Context) error
  • func (record *Record) Save(ctx context.Context) error
• type UniqueError
  • func (error UniqueError) Error() string
  • func (error UniqueError) Is(target error) bool
• type Vector32

Variables

var (
	// ErrNotFound reports that a query did not return a matching record.
	ErrNotFound = errors.New("activeso: record not found")

	// ErrUnboundRecord reports that a record was not created, loaded, or bound through a Model.
	ErrUnboundRecord = errors.New("activeso: record is not bound to a model")

	// ErrIDChanged reports that a bound record's primary key was modified.
	ErrIDChanged = errors.New("activeso: bound record ID cannot be changed")

	// ErrUnique reports that a value conflicts with a field marked activeso:"unique".
	ErrUnique = errors.New("activeso: unique constraint violated")
)

Functions

func Model

func Model[T any](db *sql.DB) *model[T]

Model binds an application-defined struct type to its Turso table using db. T must embed activeso.Record and expose one primary_key field or an id column.

Types

type Record

type Record struct {
	// contains filtered or unexported fields
}

Record embeds active-record persistence methods into an application-defined model.

func (*Record) Delete

func (record *Record) Delete(ctx context.Context) error

Delete removes the owning record from its bound model's table.

func (*Record) Save

func (record *Record) Save(ctx context.Context) error

Save persists the owning record's current field values through its bound model.

type UniqueError

type UniqueError struct {
	Field string
}

UniqueError identifies the model field that conflicts with a unique constraint.

func (UniqueError) Error

func (error UniqueError) Error() string

Error returns a human-readable unique-constraint validation error.

func (UniqueError) Is

func (error UniqueError) Is(target error) bool

Is allows errors.Is to match a UniqueError against ErrUnique.

type Vector32

type Vector32 []float32

Vector32 is a dense, 32-bit floating point vector stored with Turso's vector32 type.