Create, drop, insert table in postgres

src/main/resources/db/create_weather_table.sql

@@ -0,0 +1,19 @@
+CREATE TABLE IF NOT EXISTS weather (
+    dateTime TIMESTAMPTZ NOT NULL,
+    city VARCHAR(255) NOT NULL,
+    tempMax DOUBLE PRECISION,
+    tempMin DOUBLE PRECISION,
+    tempAvg DOUBLE PRECISION,
+    precipitation DOUBLE PRECISION,
+    windAvg DOUBLE PRECISION,
+    windMax DOUBLE PRECISION,
+    visibilityMin DOUBLE PRECISION,
+    visibilityAvg DOUBLE PRECISION,
+    snowAvg DOUBLE PRECISION,
+    atmPressure DOUBLE PRECISION,
+    dewPoint DOUBLE PRECISION,
+    humidity DOUBLE PRECISION,
+    sunDuration DOUBLE PRECISION,
+    phenomena TEXT[],
+    UNIQUE(city, dateTime)
+)

src/main/resources/db/drop_weather_table.sql

@@ -0,0 +1 @@
+DROP TABLE weather

src/main/resources/db/insert_weather_table.sql

@@ -0,0 +1,18 @@
+INSERT INTO weather (dateTime, city, tempMax, tempMin, tempAvg, precipitation, windAvg, windMax, visibilityMin, visibilityAvg, snowAvg, atmPressure, dewPoint, humidity, sunDuration, phenomena)
+    VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
+    ON CONFLICT (city, dateTime)
+    DO UPDATE SET
+        tempMax = excluded.tempMax,
+        tempMin = excluded.tempMin,
+        tempAvg = excluded.tempAvg,
+        precipitation = excluded.precipitation,
+        windAvg = excluded.windAvg,
+        windMax = excluded.windMax,
+        visibilityMin = excluded.visibilityMin,
+        visibilityAvg = excluded.visibilityAvg,
+        snowAvg = excluded.snowAvg,
+        atmPressure = excluded.atmPressure,
+        dewPoint = excluded.dewPoint,
+        humidity = excluded.humidity,
+        sunDuration = excluded.sunDuration,
+        phenomena = excluded.phenomena;

src/main/scala/db/Postgres.scala

@@ -0,0 +1,81 @@
+package db
+
+import cats.effect._
+import cats.effect.unsafe.implicits.global
+import doobie._
+import doobie.implicits._
+
+import java.time.format.DateTimeFormatter
+import java.time.{LocalDateTime, ZoneId, ZonedDateTime}
+import doobie.postgres.implicits._
+
+case class SqlContent(value: String)
+
+object Postgres {
+  def transactor[F[_]: Async]: Transactor[F] = Transactor.fromDriverManager[F](
+    "org.postgresql.Driver",
+    "jdbc:postgresql://localhost:5432/weather-tool",
+    "postgres",
+    "mysecretpassword"
+  )
+
+  def getResourceContent(path: String): IO[String] = {
+    val streamResource = Resource.make(IO(getClass.getResourceAsStream(path))) { stream =>
+      IO(stream.close()).handleErrorWith(_ => IO.unit)
+    }
+
+    streamResource.use { stream =>
+      IO(scala.io.Source.fromInputStream(stream).mkString)
+    }
+  }
+
+//  def findUserById(userId: Int)(implicit xa: Transactor[IO]): IO[Option[User]] = {
+//    sql"SELECT id, name FROM users WHERE id = $userId"
+//      .query[User]
+//      .option
+//      .transact(xa)
+//  }
+
+  def createWeatherTable(implicit xa: Transactor[IO]): IO[Int] = {
+    for {
+      createTableSql <- getResourceContent("/db/create_weather_table.sql")
+      result <- Update0(createTableSql, None).run.transact(xa)
+    } yield result
+  }
+
+  implicit val doubleOptionMeta: Meta[Option[Double]] = Meta[Double].imap(Option(_))(_.getOrElse(Double.NaN))
+
+  def insertInWeatherTable(xa: Transactor[IO]): IO[Int] = {
+    val formatter = DateTimeFormatter.ofPattern("yyyyMMdd_HHmm")
+    val dateTime = LocalDateTime.parse("20230516_1500", formatter)
+
+    val rigaZone = ZoneId.of("Europe/Riga")
+    val zonedTime: ZonedDateTime = dateTime.atZone(rigaZone)
+
+    // in pgAdmin run: ```SET TIMEZONE = 'Europe/Riga';```
+
+    for {
+      insertTableSql <- getResourceContent("/db/insert_weather_table.sql")
+      result <- Update[(ZonedDateTime, String, Option[Double], Option[Double], Option[Double], Option[Double], Option[Double], Option[Double], Option[Double], Option[Double], Option[Double], Option[Double], Option[Double], Option[Double], Option[Double], List[String])](
+        insertTableSql
+      ).run((zonedTime, "Rīga", Some(20.2), Some(8.8), Some(15.6), None, None, None, None, None, None, None, None, None, None, List("hail", "rain"))).transact(xa)
+    } yield result
+  }
+
+  def dropWeatherTable(implicit xa: Transactor[IO]): IO[Int] = {
+    for {
+      dropTableSql <- getResourceContent("/db/drop_weather_table.sql")
+      result <- Update0(dropTableSql, None).run.transact(xa)
+    } yield result
+  }
+
+  def main(args: Array[String]): Unit = {
+    val xa = transactor[IO]
+
+//    val result = createWeatherTable(xa).unsafeRunSync()
+    val result = insertInWeatherTable(xa).unsafeRunSync()
+//    val result = dropWeatherTable(xa).unsafeRunSync()
+
+    println(s"result: $result")
+  }
+}