1 files changed, 94 insertions, 24 deletions

diff --git a/internal/store/blogs.go b/internal/store/blogs.go
index b7edee0..a2e88a8 100644
--- a/internal/store/blogs.go
+++ b/internal/store/blogs.go
@@ -3,34 +3,52 @@ package store
 import (
 	"context"
 	"encoding/json"
+	"errors"
+	"fmt"
 	"time"
 
+	"github.com/gramanas/blogspace/internal/db"
 	"github.com/jackc/pgx/v5"
 )
 
+// Blog is a registry row (control database) plus the settings row of the
+// blog's own database, which Store.Open fills in.
 type Blog struct {
 	ID        int64
 	OwnerID   int64
 	Subdomain string
+	DBName    string
+	CreatedAt time.Time
+	// from the blog database
 	Title     string
 	Tagline   string
 	ThemeJSON json.RawMessage
-	CreatedAt time.Time
 	UpdatedAt time.Time
 }
 
-const blogCols = `id, owner_id, subdomain, title, tagline, theme, created_at, updated_at`
+const blogCols = `id, owner_id, subdomain, db_name, created_at`
 
 func scanBlog(row interface{ Scan(...any) error }) (*Blog, error) {
 	var b Blog
-	err := row.Scan(&b.ID, &b.OwnerID, &b.Subdomain, &b.Title, &b.Tagline, &b.ThemeJSON, &b.CreatedAt, &b.UpdatedAt)
+	err := row.Scan(&b.ID, &b.OwnerID, &b.Subdomain, &b.DBName, &b.CreatedAt)
 	if err != nil {
 		return nil, wrap(err)
 	}
 	return &b, nil
 }
 
-// CreateBlogger creates a user, their blog and a default home page in one transaction.
+func (bs *BlogStore) loadSettings(ctx context.Context, b *Blog) error {
+	err := bs.db.QueryRow(ctx, `SELECT title, tagline, theme, updated_at FROM settings`).Scan(&b.Title, &b.Tagline, &b.ThemeJSON, &b.UpdatedAt)
+	if errors.Is(err, pgx.ErrNoRows) { // registered, but the database is empty: not a 404
+		return fmt.Errorf("database %s of blog %q has no settings row (empty or wrong dump?)", b.DBName, b.Subdomain)
+	}
+	if err != nil {
+		return fmt.Errorf("settings of %s: %w", b.DBName, err)
+	}
+	return nil
+}
+
+// CreateBlogger creates a user, their blog and a default home page.
 func (s *Store) CreateBlogger(ctx context.Context, username, passwordHash, subdomain, title string) (*User, *Blog, error) {
 	tx, err := s.db.Begin(ctx)
 	if err != nil {
@@ -43,13 +61,10 @@ func (s *Store) CreateBlogger(ctx context.Context, username, passwordHash, subdo
 	if err != nil {
 		return nil, nil, err
 	}
-	b, err := createBlog(ctx, tx, u.ID, subdomain, title)
+	b, err := s.createBlog(ctx, tx, u.ID, subdomain, title)
 	if err != nil {
 		return nil, nil, err
 	}
-	if err := tx.Commit(ctx); err != nil {
-		return nil, nil, err
-	}
 	return u, b, nil
 }
 
@@ -60,30 +75,64 @@ func (s *Store) CreateBlog(ctx context.Context, ownerID int64, subdomain, title
 		return nil, err
 	}
 	defer tx.Rollback(ctx)
-	b, err := createBlog(ctx, tx, ownerID, subdomain, title)
+	return s.createBlog(ctx, tx, ownerID, subdomain, title)
+}
+
+// createBlog registers the blog in tx, then creates and fills its database and
+// commits. The registry insert goes first so a taken subdomain fails before
+// any DDL; if anything after that fails the transaction rolls back and the new
+// database is dropped again.
+func (s *Store) createBlog(ctx context.Context, tx pgx.Tx, ownerID int64, subdomain, title string) (*Blog, error) {
+	name := db.DBName(subdomain)
+	b, err := scanBlog(tx.QueryRow(ctx, `INSERT INTO blogs (owner_id, subdomain, db_name) VALUES ($1,$2,$3) RETURNING `+blogCols,
+		ownerID, subdomain, name))
+	if err != nil {
+		return nil, err
+	}
+	if err := s.cluster.CreateBlogDB(ctx, name); err != nil {
+		return nil, err
+	}
+	bs, err := s.fillNewBlog(ctx, b, title)
+	if err == nil {
+		err = tx.Commit(ctx)
+	}
 	if err != nil {
+		s.cluster.DropBlogDB(ctx, name)
 		return nil, err
 	}
-	return b, tx.Commit(ctx)
+	if err := bs.loadSettings(ctx, b); err != nil {
+		return nil, err
+	}
+	return b, nil
 }
 
-func createBlog(ctx context.Context, tx pgx.Tx, ownerID int64, subdomain, title string) (*Blog, error) {
-	b, err := scanBlog(tx.QueryRow(ctx, `INSERT INTO blogs (owner_id, subdomain, title) VALUES ($1,$2,$3) RETURNING `+blogCols,
-		ownerID, subdomain, title))
+// fillNewBlog writes what every new blog starts with: its settings, a home
+// page in the menu and the default layout.
+func (s *Store) fillNewBlog(ctx context.Context, b *Blog, title string) (*BlogStore, error) {
+	pool, err := s.cluster.Blog(ctx, b.DBName)
 	if err != nil {
 		return nil, err
 	}
+	bs := &BlogStore{db: pool}
+	btx, err := pool.Begin(ctx)
+	if err != nil {
+		return nil, err
+	}
+	defer btx.Rollback(ctx)
+	if _, err := btx.Exec(ctx, `INSERT INTO settings (title, created_at, updated_at) VALUES ($1,$2,$2)`, title, b.CreatedAt); err != nil {
+		return nil, err
+	}
 	var homeID int64
-	if err := tx.QueryRow(ctx, `INSERT INTO pages (blog_id, slug, title, nav_order, is_home) VALUES ($1,'home','Home',0,true) RETURNING id`, b.ID).Scan(&homeID); err != nil {
+	if err := btx.QueryRow(ctx, `INSERT INTO pages (slug, title, nav_order, is_home) VALUES ('home','Home',0,true) RETURNING id`).Scan(&homeID); err != nil {
 		return nil, wrap(err)
 	}
-	if err := addMenuPage(ctx, tx, b.ID, homeID); err != nil {
+	if err := addMenuPage(ctx, btx, homeID); err != nil {
 		return nil, err
 	}
-	if err := insertDefaultModules(ctx, tx, b.ID); err != nil {
+	if err := insertDefaultModules(ctx, btx); err != nil {
 		return nil, err
 	}
-	return b, nil
+	return bs, btx.Commit(ctx)
 }
 
 func (s *Store) BlogByID(ctx context.Context, id int64) (*Blog, error) {
@@ -98,17 +147,38 @@ func (s *Store) BlogByOwner(ctx context.Context, ownerID int64) (*Blog, error) {
 	return scanBlog(s.db.QueryRow(ctx, `SELECT `+blogCols+` FROM blogs WHERE owner_id=$1`, ownerID))
 }
 
-func (s *Store) UpdateBlogSettings(ctx context.Context, id int64, title, tagline string) error {
-	_, err := s.db.Exec(ctx, `UPDATE blogs SET title=$2, tagline=$3, updated_at=now() WHERE id=$1`, id, title, tagline)
-	return err
+// ListBlogs returns every registered blog, oldest first.
+func (s *Store) ListBlogs(ctx context.Context) ([]Blog, error) {
+	rows, err := s.db.Query(ctx, `SELECT `+blogCols+` FROM blogs ORDER BY id`)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	var out []Blog
+	for rows.Next() {
+		b, err := scanBlog(rows)
+		if err != nil {
+			return nil, err
+		}
+		out = append(out, *b)
+	}
+	return out, rows.Err()
+}
+
+// DeleteBlog unregisters the blog and drops its database.
+func (s *Store) DeleteBlog(ctx context.Context, b *Blog) error {
+	if _, err := s.db.Exec(ctx, `DELETE FROM blogs WHERE id=$1`, b.ID); err != nil {
+		return err
+	}
+	return s.cluster.DropBlogDB(ctx, b.DBName)
 }
 
-func (s *Store) UpdateBlogTheme(ctx context.Context, id int64, theme json.RawMessage) error {
-	_, err := s.db.Exec(ctx, `UPDATE blogs SET theme=$2, updated_at=now() WHERE id=$1`, id, theme)
+func (bs *BlogStore) UpdateSettings(ctx context.Context, title, tagline string) error {
+	_, err := bs.db.Exec(ctx, `UPDATE settings SET title=$1, tagline=$2, updated_at=now()`, title, tagline)
 	return err
 }
 
-func (s *Store) DeleteBlog(ctx context.Context, id int64) error {
-	_, err := s.db.Exec(ctx, `DELETE FROM blogs WHERE id=$1`, id)
+func (bs *BlogStore) UpdateTheme(ctx context.Context, theme json.RawMessage) error {
+	_, err := bs.db.Exec(ctx, `UPDATE settings SET theme=$1, updated_at=now()`, theme)
 	return err
 }