streaming functions for doobie and slick with tests

.github/workflows/build.yml

@@ -29,14 +29,14 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - scala: 2.11.12
-            scalaShort: "2.11"
-            overall: 0.0
-            changed: 80.0
           - scala: 2.12.17
             scalaShort: "2.12"
             overall: 0.0
             changed: 80.0
+          - scala: 2.13.12
+            scalaShort: "2.13"
+            overall: 0.0
+            changed: 80.0
     name: Build and test
     steps:
       - name: Checkout code
@@ -53,6 +53,7 @@ jobs:
             ${{ github.workspace }}/core/target/scala-${{ matrix.scalaShort }}/jacoco/report/jacoco.xml
             ${{ github.workspace }}/examples/target/scala-${{ matrix.scalaShort }}/jacoco/report/jacoco.xml
             ${{ github.workspace }}/slick/target/scala-${{ matrix.scalaShort }}/jacoco/report/jacoco.xml
+            ${{ github.workspace }}/doobie/target/scala-${{ matrix.scalaShort }}/jacoco/report/jacoco.xml
           key: ${{ runner.os }}-${{ matrix.scalaShort }}-${{ hashFiles('**/jacoco.xml') }}
 
   jacoco:
@@ -62,14 +63,14 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - scala: 2.11.12
-            scalaShort: "2.11"
-            overall: 0.0
-            changed: 80.0
           - scala: 2.12.17
             scalaShort: "2.12"
             overall: 0.0
             changed: 80.0
+          - scala: 2.13.12
+            scalaShort: "2.13"
+            overall: 0.0
+            changed: 80.0
     name: JaCoCo Code Coverage ${{matrix.scala}}
     steps:
       - name: Checkout code
@@ -80,6 +81,7 @@ jobs:
             ${{ github.workspace }}/core/target/scala-${{ matrix.scalaShort }}/jacoco/report/jacoco.xml
             ${{ github.workspace }}/examples/target/scala-${{ matrix.scalaShort }}/jacoco/report/jacoco.xml
             ${{ github.workspace }}/slick/target/scala-${{ matrix.scalaShort }}/jacoco/report/jacoco.xml
+            ${{ github.workspace }}/doobie/target/scala-${{ matrix.scalaShort }}/jacoco/report/jacoco.xml
           key: ${{ runner.os }}-${{ matrix.scalaShort }}-${{ hashFiles('**/jacoco.xml') }}
       - name: Setup Scala
         uses: olafurpg/setup-scala@v10
@@ -92,6 +94,7 @@ jobs:
           paths: >
             ${{ github.workspace }}/core/target/scala-${{ matrix.scalaShort }}/jacoco/report/jacoco.xml,
             ${{ github.workspace }}/slick/target/scala-${{ matrix.scalaShort }}/jacoco/report/jacoco.xml
+            ${{ github.workspace }}/doobie/target/scala-${{ matrix.scalaShort }}/jacoco/report/jacoco.xml
           # examples don't need code coverage - at least not now
           token: ${{ secrets.GITHUB_TOKEN }}
           min-coverage-overall: ${{ matrix.overall }}

.gitignore

@@ -46,3 +46,5 @@ dist
 test-output
 build.log
 .bsp
+/.bloop/
+/.metals/

.scalafmt.conf

@@ -0,0 +1,32 @@
+version = "3.5.3"
+runner.dialect = scala213
+
+maxColumn = 120
+
+align.preset = some
+align.multiline = false
+
+align.tokens = [
+  {
+    code = "<-"
+  },
+  {
+    code = "=>"
+    owners = [{
+      regex = "Case"
+    }]
+  }
+]
+
+indent.main = 2
+indent.defnSite = 2
+
+lineEndings = unix
+
+docstrings.blankFirstLine = yes
+docstrings.style = AsteriskSpace
+docstrings.wrap = no
+docstrings.removeEmpty = true
+
+align.openParenDefnSite = false
+align.openParenCallSite = false

README.md

@@ -54,48 +54,50 @@ Currently, the library is developed with Postgres as the target DB. But the appr
 
 #### Sbt
 
+Import one of the two available module at the moment. Slick module works with Scala Futures. Doobie module works with any effect type (typically IO or ZIO) provided cats effect's Async instance is available.
+
 ```scala
-libraryDependencies ++= Seq(
-  "za.co.absa.fa-db" %% "core"  % "X.Y.Z",
-  "za.co.absa.fa-db" %% "slick" % "X.Y.Z"
-)
+libraryDependencies *= "za.co.absa.fa-db" %% "slick"  % "X.Y.Z"
+libraryDependencies *= "za.co.absa.fa-db" %% "doobie"  % "X.Y.Z"
 ```
 
 #### Maven
 
-##### Scala 2.11
+##### Scala 2.12
 
 Modules:
-* Core [![Maven Central](https://maven-badges.herokuapp.com/maven-central/za.co.absa.fa-db/core_2.11/badge.svg)](https://maven-badges.herokuapp.com/maven-central/za.co.absa.fa-db/core_2.11)
-* Slick [![Maven Central](https://maven-badges.herokuapp.com/maven-central/za.co.absa.fa-db/slick_2.11/badge.svg)](https://maven-badges.herokuapp.com/maven-central/za.co.absa.fa-db/slick_2.11)
+* Core [![Maven Central](https://maven-badges.herokuapp.com/maven-central/za.co.absa.fa-db/core_2.12/badge.svg)](https://maven-badges.herokuapp.com/maven-central/za.co.absa.fa-db/core_2.12)
+* Slick [![Maven Central](https://maven-badges.herokuapp.com/maven-central/za.co.absa.fa-db/slick_2.12/badge.svg)](https://maven-badges.herokuapp.com/maven-central/za.co.absa.fa-db/slick_2.12)
+* Doobie [![Maven Central](https://maven-badges.herokuapp.com/maven-central/za.co.absa.fa-db/doobie_2.12/badge.svg)](https://maven-badges.herokuapp.com/maven-central/za.co.absa.fa-db/doobie_2.12)
 
 ```xml
 <dependency>
-   <groupId>za.co.absa.fa-db</groupId>
-   <artifactId>core_2.11</artifactId>
-   <version>${latest_version}</version>
+    <groupId>za.co.absa.fa-db</groupId>
+    <artifactId>slick_2.12</artifactId>
+    <version>${latest_version}</version>
 </dependency>
 <dependency>
-<groupId>za.co.absa.fa-db</groupId>
-<artifactId>slick_2.11</artifactId>
-<version>${latest_version}</version>
+    <groupId>za.co.absa.fa-db</groupId>
+    <artifactId>doobie_2.12</artifactId>
+    <version>${latest_version}</version>
 </dependency>
 ```
 
-### Scala 2.12 
+### Scala 2.13
 Modules:
-* Core [![Maven Central](https://maven-badges.herokuapp.com/maven-central/za.co.absa.fa-db/core_2.12/badge.svg)](https://maven-badges.herokuapp.com/maven-central/za.co.absa.fa-db/core_2.12)
-* Slick [![Maven Central](https://maven-badges.herokuapp.com/maven-central/za.co.absa.fa-db/slick_2.12/badge.svg)](https://maven-badges.herokuapp.com/maven-central/za.co.absa.fa-db/slick_2.12)
+* Core [![Maven Central](https://maven-badges.herokuapp.com/maven-central/za.co.absa.fa-db/core_2.13/badge.svg)](https://maven-badges.herokuapp.com/maven-central/za.co.absa.fa-db/core_2.13)
+* Slick [![Maven Central](https://maven-badges.herokuapp.com/maven-central/za.co.absa.fa-db/slick_2.13/badge.svg)](https://maven-badges.herokuapp.com/maven-central/za.co.absa.fa-db/slick_2.13)
+* Doobie [![Maven Central](https://maven-badges.herokuapp.com/maven-central/za.co.absa.fa-db/doobie_2.13/badge.svg)](https://maven-badges.herokuapp.com/maven-central/za.co.absa.fa-db/doobie_2.13)
 
 ```xml
 <dependency>
-   <groupId>za.co.absa.fa-db</groupId>
-   <artifactId>core_2.12</artifactId>
-   <version>${latest_version}</version>
+    <groupId>za.co.absa.fa-db</groupId>
+    <artifactId>slick_2.13</artifactId>
+    <version>${latest_version}</version>
 </dependency>
 <dependency>
     <groupId>za.co.absa.fa-db</groupId>
-    <artifactId>slick_2.12</artifactId>
+    <artifactId>doobie_2.13</artifactId>
     <version>${latest_version}</version>
 </dependency>
 ```
@@ -109,13 +111,17 @@ Text about status codes returned from the database function can be found [here](
 
 ## Slick module
 
-Slick module is the first (and so far only) implementation of fa-db able to execute. As the name suggests it runs on 
-[Slick library](https://github.com/slick/slick) and also brings in the [Slickpg library](https://github.com/tminglei/slick-pg/) for extended Postgres type support.
+As the name suggests it runs on [Slick library](https://github.com/slick/slick) and also brings in the [Slickpg library](https://github.com/tminglei/slick-pg/) for extended Postgres type support.
 
 It brings:
 
 * `class SlickPgEngine` - implementation of _Core_'s `DBEngine` executing the queries via Slick
-* `trait SlickFunction` and `trait SlickFunctionWithStatusSupport` - mix-in traits to use with `FaDbFunction` descendants
+* `class SlickPgStreamingEngine` - implementation of _Core_'s `DBStreamingEngine` executing the queries via Slick in a streaming fashion
+* `class SlickSingleResultFunction` - abstract class for DB functions returning single result
+* `class SlickMultipleResultFunction` - abstract class for DB functions returning sequence of results
+* `class SlickOptionalResultFunction` - abstract class for DB functions returning optional result
+* `class SlickSingleResultFunctionWithStatus` - abstract class for DB functions with status handling; it requires an implementation of `StatusHandling` to be mixed-in (`StandardStatusHandling` available out-of-the-box)
+* `class SlickStreamingResultFunction` - abstract class for DB functions returning sequence of results (fs2.Stream) in a streaming fashion
 * `trait FaDbPostgresProfile` - to bring support for Postgres and its extended data types in one class (except JSON, as there are multiple implementations for this data type in _Slick-Pg_)
 * `object FaDbPostgresProfile` - instance of the above trait for direct use
 
@@ -137,6 +143,21 @@ val hStore: Option[Map[String, String]] = pr.nextHStoreOption
 val macAddr: Option[MacAddrString] = pr.nextMacAddrOption
 ```
 
+## Doobie module
+
+As the name suggests it runs on [Doobie library](https://tpolecat.github.io/doobie/). The main benefit of the module is that it allows to use any effect type (typically IO or ZIO) therefore is more suitable for functional programming. It also brings in the [Doobie-Postgres library](https://tpolecat.github.io/doobie/docs/14-PostgreSQL.html) for extended Postgres type support.
+
+It brings:
+
+* `class DoobieEngine` - implementation of _Core_'s `DBEngine` executing the queries via Doobie. The class is type parameterized with the effect type.
+* `class DoobieStreamingEngine` - implementation of _Core_'s `DBStreamingEngine` executing the queries via Doobie in a streaming fashion. The class is type parameterized with the effect type.
+* `class DoobieSingleResultFunction` - abstract class for DB functions returning single result
+* `class DoobieMultipleResultFunction` - abstract class for DB functions returning sequence of results
+* `class DoobieOptionalResultFunction` - abstract class for DB functions returning optional result
+* `class DoobieSingleResultFunctionWithStatus` - abstract class for DB functions with status handling; it requires an implementation of `StatusHandling` to be mixed-in (`StandardStatusHandling` available out-of-the-box)
+* `class DoobieStreamingResultFunction` - abstract class for DB functions returning sequence of results (fs2.Stream) in a streaming fashion
+Since Doobie also interoperates with ZIO, there is an example of how a database connection can be properly established within a ZIO application. Please see [this file](doobie/zio-setup.md) for more details.
+
 ## Testing
 
 ### How to generate unit tests code coverage report

build.sbt

@@ -19,11 +19,11 @@ import com.github.sbt.jacoco.report.JacocoReportSettings
 
 ThisBuild / organization := "za.co.absa.fa-db"
 
-lazy val scala211 = "2.11.12"
 lazy val scala212 = "2.12.17"
+lazy val scala213 = "2.13.12"
 
-ThisBuild / scalaVersion := scala211
-ThisBuild / crossScalaVersions := Seq(scala211, scala212)
+ThisBuild / scalaVersion := scala213
+ThisBuild / crossScalaVersions := Seq(scala212, scala213)
 
 ThisBuild / versionScheme := Some("early-semver")
 
@@ -49,7 +49,7 @@ lazy val commonJacocoExcludes: Seq[String] = Seq(
 )
 
 lazy val parent = (project in file("."))
-  .aggregate(faDbCore, faDBSlick, faDBExamples)
+  .aggregate(faDbCore, faDBSlick, faDBDoobie, faDBExamples)
   .settings(
     name := "root",
     libraryDependencies ++= rootDependencies(scalaVersion.value),
@@ -88,6 +88,20 @@ lazy val faDBSlick = (project in file("slick"))
     jacocoExcludes := commonJacocoExcludes
   )
 
+lazy val faDBDoobie = (project in file("doobie"))
+  .configs(IntegrationTest)
+  .settings(
+    name := "doobie",
+    libraryDependencies ++= doobieDependencies(scalaVersion.value),
+    javacOptions ++= commonJavacOptions,
+    scalacOptions ++= commonScalacOptions,
+    Defaults.itSettings,
+  ).dependsOn(faDbCore)
+  .settings(
+    jacocoReportSettings := commonJacocoReportSettings.withTitle(s"doobie:slick Jacoco Report - scala:${scalaVersion.value}"),
+    jacocoExcludes := commonJacocoExcludes
+  )
+
 lazy val faDBExamples = (project in file("examples"))
   .configs(IntegrationTest)
   .settings(

core/src/main/scala/za/co/absa/fadb/DBEngine.scala

@@ -16,57 +16,69 @@
 
 package za.co.absa.fadb
 
-import scala.concurrent.{ExecutionContext, Future}
+import cats.Monad
+import cats.implicits.toFunctorOps
+import za.co.absa.fadb.exceptions.StatusException
+
 import scala.language.higherKinds
 
 /**
-  * A basis to represent a database executor
-  */
-trait DBEngine {
+ *  `DBEngine` is an abstract class that represents a database engine.
+ *  It provides methods to execute queries and fetch results from a database.
+ *  @tparam F - The type of the context in which the database queries are executed.
+ */
+abstract class DBEngine[F[_]: Monad] {
 
   /**
-    * A type representing the (SQL) query within the engine
-    * @tparam T - the return type of the query
-    */
-  type QueryType[T] <: Query[T]
+   *  A type representing the (SQL) query within the engine
+   *  @tparam R - the return type of the query
+   */
+  type QueryType[R] <: Query[R]
+  type QueryWithStatusType[R] <: QueryWithStatus[_, _, R]
 
-  implicit val executor: ExecutionContext
+  /**
+   *  The actual query executioner of the queries of the engine
+   *  @param query  - the query to execute
+   *  @tparam R     - return type of the query
+   *  @return       - sequence of the results of database query
+   */
+  protected def run[R](query: QueryType[R]): F[Seq[R]]
 
   /**
-    * The actual query executioner of the queries of the engine
-    * @param query  - the query to execute
-    * @tparam R     - return the of the query
-    * @return       - sequence of the results of database query
-    */
-  protected def run[R](query: QueryType[R]): Future[Seq[R]]
+   *  The actual query executioner of the queries of the engine with status
+   *  @param query  - the query to execute
+   *  @tparam R     - return type of the query
+   *  @return       - result of database query with status
+   */
+  def runWithStatus[R](query: QueryWithStatusType[R]): F[Either[StatusException, R]]
 
   /**
-    * Public method to execute when query is expected to return multiple results
-    * @param query  - the query to execute
-    * @tparam R     - return the of the query
-    * @return       - sequence of the results of database query
-    */
-  def fetchAll[R](query: QueryType[R]): Future[Seq[R]] = run(query)
+   *  Public method to execute when query is expected to return multiple results
+   *  @param query  - the query to execute
+   *  @tparam R     - return type of the query
+   *  @return       - sequence of the results of database query
+   */
+  def fetchAll[R](query: QueryType[R]): F[Seq[R]] = {
+    run(query)
+  }
 
   /**
-    * Public method to execute when query is expected to return exactly one row
-    * @param query  - the query to execute
-    * @tparam R     - return the of the query
-    * @return       - sequence of the results of database query
-    */
-  def fetchHead[R](query: QueryType[R]): Future[R] = {
+   *  Public method to execute when query is expected to return exactly one row
+   *  @param query  - the query to execute
+   *  @tparam R     - return type of the query
+   *  @return       - sequence of the results of database query
+   */
+  def fetchHead[R](query: QueryType[R]): F[R] = {
     run(query).map(_.head)
   }
 
   /**
-    * Public method to execute when query is expected to return one or no results
-    * @param query  - the query to execute
-    * @tparam R     - return the of the query
-    * @return       - sequence of the results of database query
-    */
-
-  def fetchHeadOption[R](query:  QueryType[R]): Future[Option[R]] = {
+   *  Public method to execute when query is expected to return one or no results
+   *  @param query  - the query to execute
+   *  @tparam R     - return type of the query
+   *  @return       - sequence of the results of database query
+   */
+  def fetchHeadOption[R](query: QueryType[R]): F[Option[R]] = {
     run(query).map(_.headOption)
   }
 }
-