storage layer

README.md

@@ -2,23 +2,18 @@
 **Fog** is a **F**orum mixed with a Bl**og**, intended to encourage fruitful
 discussion and the spread of knowledge.
 
-## Posts
+To get started:
-These are your typical blog posts, written in Markdown. They can include video,
+1. Install [Go](https://go.dev).
-images and (one day) custom JS for interactivity.
+2. Install [migrate](https://github.com/golang-migrate/migrate):
+```sh
+$ go install -tags 'postgres' github.com/golang-migrate/migrate/v4/cmd/migrate@latest
+```
+3. Install [PostgreSQL](https://postgresql.org).
+4. Create a new Postgres user and database.
+5. Set your environment variables. See [`docs/envvars.mds`](docs/envvars.md)
+for an list of variables that need to be set.
+6. Run `scripts/migrateup` to setup the database tables.
+7. Run `go run cmd/api` to start the backend.
 
-Posts can be replies to other posts and will be directly linked underneath the
+Frontend has a seperate setup. See [`web/README.md`](web/README.md) for more
-main post. You can reply to multiple posts at once, and you will be linked in
+info.
-the replies of all posts. Neighbouring posts which reply to the same parent post
-will be linked under the reply post.
-
-After you make a post, you must wait a customizable amount of time before
-making another (default is a day). Think before you speak.
-
-There is no voting system and no comments system. If you have something to say
-about a post, say it. Views on a post are also not recorded.
-
-## Channels
-Channels are a way of sorting posts by their general theme. All posts made to a
-channel can be sorted by newest (default), oldest and random.
-
-Moderators can pin posts to the top of channels.

cmd/api/api.go

@@ -8,15 +8,27 @@ import (
 	"path"
 	"strings"
 	"time"
+
+	"midnadimple.com/fog/internal/store"
 )
 
 type application struct {
 	config config
-	v1     *v1Handler
+	store  store.Storage
+
+	v1 *v1Handler
 }
 
 type config struct {
 	addr string
+	db   dbConfig
+}
+
+type dbConfig struct {
+	addr         string
+	maxOpenConns int
+	maxIdleConns int
+	maxIdleTime  time.Duration
 }
 
 func (h *application) ServeHTTP(w http.ResponseWriter, r *http.Request) {
@@ -71,6 +83,10 @@ func (h *application) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 }
 
 func (app *application) run() error {
+	app.v1 = &v1Handler{
+		healthCheck: &healthCheckHandler{},
+	}
+
 	srv := &http.Server{
 		Addr:         app.config.addr,
 		Handler:      app,

cmd/api/main.go

@@ -2,22 +2,39 @@ package main
 
 import (
 	"log"
+	"time"
 
+	"midnadimple.com/fog/internal/db"
 	"midnadimple.com/fog/internal/env"
+	"midnadimple.com/fog/internal/store/postgres"
 )
 
 func main() {
 	cfg := config{
 		addr: env.GetString("FOG_ADDR", ":8080"),
+		db: dbConfig{
+			addr:         env.GetString("FOG_DB_ADDR", "postgres://foguser:fogpass@localhost/fog?sslmode=disable"),
+			maxOpenConns: env.GetInt("FOG_DB_MAX_OPEN_CONNS", 30),
+			maxIdleConns: env.GetInt("FOG_DB_MAX_IDLE_CONNS", 30),
+			maxIdleTime:  env.GetDuration("FOG_DB_MAX_IDLE_TIME", 15*time.Minute),
+		},
 	}
 
-	v1 := &v1Handler{
+	db, err := db.New(
-		healthCheck: &healthCheckHandler{},
+		cfg.db.addr,
+		cfg.db.maxOpenConns,
+		cfg.db.maxIdleConns,
+		cfg.db.maxIdleTime,
+	)
+	if err != nil {
+		log.Fatalln(err)
 	}
 
+	store := postgres.NewPostgresStorage(db)
+
 	app := &application{
 		config: cfg,
-		v1:     v1,
+		store:  store,
 	}
 
 	log.Fatal(app.run())

cmd/migrate/migrations/000001_create_users.down.sql

@@ -0,0 +1 @@
+DROP TABLE IF EXISTS users;

cmd/migrate/migrations/000001_create_users.up.sql

@@ -0,0 +1,9 @@
+CREATE EXTENSION IF NOT EXISTS citext;
+
+CREATE TABLE IF NOT EXISTS users(
+	id bigserial PRIMARY KEY,
+	username varchar(255) UNIQUE NOT NULL,
+	email citext UNIQUE NOT NULL,
+	password bytea NOT NULL,
+	created_at timestamp(0) with time zone NOT NULL DEFAULT NOW()
+);

cmd/migrate/migrations/000002_create_posts.down.sql

@@ -0,0 +1 @@
+DROP TABLE IF EXISTS posts

cmd/migrate/migrations/000002_create_posts.up.sql

@@ -0,0 +1,10 @@
+CREATE TABLE IF NOT EXISTS posts(
+	id bigserial PRIMARY KEY,
+	content text NOT NULL,
+	title text NOT NULL,
+	user_id bigserial NOT NULL,
+	tags text[],
+	reply_ids integer[],
+	created_at timestamp(0) with time zone NOT NULL DEFAULT NOW(),
+	updated_at timestamp(0) with time zone NOT NULL DEFAULT NOW()
+);

cmd/migrate/migrations/000003_alter_posts.down.sql

@@ -0,0 +1,3 @@
+ALTER TABLE
+	posts
+DROP CONSTRAINT fk_user;

cmd/migrate/migrations/000003_alter_posts.up.sql

@@ -0,0 +1,3 @@
+ALTER TABLE
+	posts
+ADD CONSTRAINT fk_user FOREIGN KEY (user_id) REFERENCES users (id);

docs/design.md

@@ -0,0 +1,22 @@
+# Posts
+These are your typical blog posts, written in Markdown. They can include video,
+images and (one day) custom JS for interactivity.
+
+Posts can be replies to other posts and will be directly linked underneath the
+main post. You can reply to multiple posts at once, and you will be linked in
+the replies of all posts. Neighbouring posts which reply to the same parent post
+will be linked under the reply post.
+
+After you make a post, you must wait a customizable amount of time before
+making another (default is a day). Think before you speak.
+
+There is no voting system and no comments system. If you have something to say
+about a post, say it. Views on a post are also not recorded.
+
+# Channels
+Channels are a way of sorting posts by their general theme. All posts in a given
+channel can be sorted by newest (default), oldest and random.
+
+Moderators can pin posts to the top of channels.
+
+A post must belong to one or more channels.

docs/envvars.md

@@ -0,0 +1,20 @@
+# List of all Environment Variables
+You should set these in your `.profile`. Even though there are defaults, the
+scripts still expect to have these variables in order to perform migrations,
+so you should set them.
+
+## FOG_ADDR
+Address the backend server listens on. Default is ":8080"
+
+## FOG_DB_ADDR
+Address of the Postgres database. Default is:
+"postgres://foguser:fogpass@localhost/fog?sslmode=disable"
+
+## FOG_DB_MAX_OPEN_CONNS
+How many database connections can be open at once. Default is 30
+
+## FOG_DB_MAX_IDLE_CONNS
+How many database connections can be idling at once. Default is 30
+
+## FOG_DB_MAX_IDLE_TIME
+How long a database connection should idle before being closed Default is "15m"

go.mod

@@ -1,3 +1,5 @@
 module midnadimple.com/fog
 
 go 1.23.4
+
+require github.com/lib/pq v1.10.9

go.sum

@@ -0,0 +1,2 @@
+github.com/lib/pq v1.10.9 h1:YXG7RB+JIjhP29X+OtkiDnYaXQwpS4JEWq7dtCCRUEw=
+github.com/lib/pq v1.10.9/go.mod h1:AlVN5x4E4T544tWzH6hKfbfQvm3HdbOxrmggDNAPY9o=

internal/db/db.go

@@ -0,0 +1,31 @@
+package db
+
+import (
+	"context"
+	"database/sql"
+	"log"
+	"time"
+)
+
+func New(addr string, maxOpenConns, maxIdleConns int, maxIdleTime time.Duration) (*sql.DB, error) {
+	db, err := sql.Open("postgres", addr)
+	if err != nil {
+		return nil, err
+	}
+
+	defer db.Close()
+	log.Println("database connection pool established")
+
+	db.SetMaxOpenConns(maxOpenConns)
+	db.SetMaxIdleConns(maxIdleConns)
+	db.SetConnMaxIdleTime(maxIdleTime)
+
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	if err := db.PingContext(ctx); err != nil {
+		return nil, err
+	}
+
+	return db, nil
+}

internal/env/env.go

@@ -4,11 +4,13 @@ import (
 	"log"
 	"os"
 	"strconv"
+	"time"
 )
 
 func GetString(key, fallback string) string {
 	val, ok := os.LookupEnv(key)
 	if !ok {
+		log.Printf("Failed to lookup enviornment variable with key %s. Using fallback value '%s'", key, fallback)
 		return fallback
 	}
 
@@ -18,6 +20,7 @@ func GetString(key, fallback string) string {
 func GetInt(key string, fallback int) int {
 	val, ok := os.LookupEnv(key)
 	if !ok {
+		log.Printf("Failed to lookup enviornment variable with key %s. Using fallback value '%d'", key, fallback)
 		return fallback
 	}
 
@@ -29,3 +32,19 @@ func GetInt(key string, fallback int) int {
 
 	return valInt
 }
+
+func GetDuration(key string, fallback time.Duration) time.Duration {
+	val, ok := os.LookupEnv(key)
+	if !ok {
+		log.Printf("Failed to lookup enviornment variable with key %s. Using fallback value '%s'", key, fallback)
+		return fallback
+	}
+
+	duration, err := time.ParseDuration(val)
+	if err != nil {
+		log.Printf("Failed to convert environment variable with key %s and value %s to duration. Using fallback %d. (err: %s)", key, val, fallback, err)
+		return fallback
+	}
+
+	return duration
+}

internal/store/postgres/postgres.go

@@ -0,0 +1,20 @@
+package postgres
+
+import (
+	"database/sql"
+	"time"
+
+	"midnadimple.com/fog/internal/store"
+)
+
+func NewPostgresStorage(db *sql.DB) store.Storage {
+	return store.Storage{
+		Posts: &PostsStore{db},
+		Users: &UsersStore{db},
+	}
+}
+
+func parseTimestamp(valPtr *time.Time, str string) error {
+
+	return nil
+}

internal/store/postgres/posts.go

@@ -0,0 +1,52 @@
+package postgres
+
+import (
+	"context"
+	"database/sql"
+	"time"
+
+	"github.com/lib/pq"
+
+	"midnadimple.com/fog/internal/store"
+)
+
+type PostsStore struct {
+	DB *sql.DB
+}
+
+func (s *PostsStore) Create(ctx context.Context, post *store.Post) error {
+	query := `
+	INSERT INTO posts (content, title, user_id, tags, reply_ids)
+	VALUES ($1, $2, $3, $4) RETURNING id, created_at, updated_at
+`
+	var createdAtStr, updatedAtStr string
+	err := s.DB.QueryRowContext(
+		ctx,
+		query,
+		post.Content,
+		post.Title,
+		post.UserID,
+		pq.Array(post.Tags),
+		pq.Array(post.ReplyIDs),
+	).Scan(
+		&post.ID,
+		&createdAtStr,
+		&updatedAtStr,
+	)
+
+	if err != nil {
+		return err
+	}
+
+	post.CreatedAt, err = pq.ParseTimestamp(time.UTC, createdAtStr)
+	if err != nil {
+		return err
+	}
+
+	post.UpdatedAt, err = pq.ParseTimestamp(time.UTC, updatedAtStr)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}

internal/store/postgres/users.go

@@ -0,0 +1,44 @@
+package postgres
+
+import (
+	"context"
+	"database/sql"
+	"time"
+
+	"github.com/lib/pq"
+	"midnadimple.com/fog/internal/store"
+)
+
+type UsersStore struct {
+	DB *sql.DB
+}
+
+func (s *UsersStore) Create(ctx context.Context, user *store.User) error {
+	query := `
+	INSERT INTO users (username, password, email) VALUES($1, $2, $3) RETURNING id, created_at
+	`
+
+	var createdAtStr string
+
+	err := s.DB.QueryRowContext(
+		ctx,
+		query,
+		user.Username,
+		user.Password,
+		user.Email,
+	).Scan(
+		&user.ID,
+		&createdAtStr,
+	)
+
+	if err != nil {
+		return err
+	}
+
+	user.CreatedAt, err = pq.ParseTimestamp(time.UTC, createdAtStr)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}

internal/store/storage.go

@@ -0,0 +1,34 @@
+package store
+
+import (
+	"context"
+	"time"
+)
+
+type Post struct {
+	ID        int64     `json:"id"`
+	Content   string    `json:"content"`
+	Title     string    `json:"title"`
+	UserID    int64     `json:"user_id"`
+	Tags      []int64   `json:"tags"`
+	ReplyIDs  []int64   `json:"reply_ids"`
+	CreatedAt time.Time `json:"created_at"`
+	UpdatedAt time.Time `json:"updated_at"`
+}
+
+type User struct {
+	ID        int64     `json:"id"`
+	Username  string    `json:"username"`
+	Email     int64     `json:"email"`
+	Password  string    `json:"-"`
+	CreatedAt time.Time `json:"created_at"`
+}
+
+type Storage struct {
+	Posts interface {
+		Create(context.Context, *Post) error
+	}
+	Users interface {
+		Create(context.Context, *User) error
+	}
+}

scripts/migratedown.ps1

@@ -0,0 +1 @@
+migrate -path="./cmd/migrate/migrations" -database="$env:FOG_DB_ADDR" down

scripts/migratenew.ps1

@@ -0,0 +1 @@
+migrate create -seq -ext sql -dir "./cmd/migrate/migrations" $args[0]

scripts/migrateup.ps1

@@ -0,0 +1 @@
+migrate -path="./cmd/migrate/migrations" -database="$env:FOG_DB_ADDR" up