diff --git a/.gitattributes b/.gitattributes new file mode 100644 index 0000000..097f9f9 --- /dev/null +++ b/.gitattributes @@ -0,0 +1,9 @@ +# +# https://help.github.com/articles/dealing-with-line-endings/ +# +# Linux start script should use lf +/gradlew text eol=lf + +# These are Windows script files and should use crlf +*.bat text eol=crlf + diff --git a/.gitignore b/.gitignore index f409a90..816f381 100644 --- a/.gitignore +++ b/.gitignore @@ -23,4 +23,9 @@ hs_err_pid* replay_pid* -.idea \ No newline at end of file +.idea +# Ignore Gradle project-specific cache directory +.gradle + +# Ignore Gradle build output directory +build diff --git a/build.gradle.kts b/build.gradle.kts new file mode 100644 index 0000000..57762d3 --- /dev/null +++ b/build.gradle.kts @@ -0,0 +1,30 @@ +plugins { + id("org.jetbrains.kotlin.jvm") version "1.7.10" + + // Apply the java-library plugin for API and implementation separation. + `java-library` +} + +repositories { + // Use Maven Central for resolving dependencies. + mavenCentral() +} + +dependencies { + implementation("com.zaxxer:HikariCP:7.0.2") + implementation("org.postgresql:postgresql:42.7.9") + implementation("com.fasterxml.jackson.core:jackson-databind:2.17.1") + implementation("com.fasterxml.jackson.datatype:jackson-datatype-jsr310:2.17.1") + implementation("com.fasterxml.jackson.datatype:jackson-datatype-jdk8:2.17.1") + implementation("com.google.guava:guava:32.1.3-jre") + testImplementation("org.junit.jupiter:junit-jupiter:5.9.2") + testImplementation("org.assertj:assertj-core:3.24.2") +} + +testing { + suites { + val test by getting(JvmTestSuite::class) { + useJUnitJupiter("5.9.2") + } + } +} \ No newline at end of file diff --git a/gradlew b/gradlew new file mode 100755 index 0000000..65dcd68 --- /dev/null +++ b/gradlew @@ -0,0 +1,244 @@ +#!/bin/sh + +# +# Copyright © 2015-2021 the original authors. +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# https://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. +# + +############################################################################## +# +# Gradle start up script for POSIX generated by Gradle. +# +# Important for running: +# +# (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is +# noncompliant, but you have some other compliant shell such as ksh or +# bash, then to run this script, type that shell name before the whole +# command line, like: +# +# ksh Gradle +# +# Busybox and similar reduced shells will NOT work, because this script +# requires all of these POSIX shell features: +# * functions; +# * expansions «$var», «${var}», «${var:-default}», «${var+SET}», +# «${var#prefix}», «${var%suffix}», and «$( cmd )»; +# * compound commands having a testable exit status, especially «case»; +# * various built-in commands including «command», «set», and «ulimit». +# +# Important for patching: +# +# (2) This script targets any POSIX shell, so it avoids extensions provided +# by Bash, Ksh, etc; in particular arrays are avoided. +# +# The "traditional" practice of packing multiple parameters into a +# space-separated string is a well documented source of bugs and security +# problems, so this is (mostly) avoided, by progressively accumulating +# options in "$@", and eventually passing that to Java. +# +# Where the inherited environment variables (DEFAULT_JVM_OPTS, JAVA_OPTS, +# and GRADLE_OPTS) rely on word-splitting, this is performed explicitly; +# see the in-line comments for details. +# +# There are tweaks for specific operating systems such as AIX, CygWin, +# Darwin, MinGW, and NonStop. +# +# (3) This script is generated from the Groovy template +# https://github.com/gradle/gradle/blob/HEAD/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt +# within the Gradle project. +# +# You can find Gradle at https://github.com/gradle/gradle/. +# +############################################################################## + +# Attempt to set APP_HOME + +# Resolve links: $0 may be a link +app_path=$0 + +# Need this for daisy-chained symlinks. +while + APP_HOME=${app_path%"${app_path##*/}"} # leaves a trailing /; empty if no leading path + [ -h "$app_path" ] +do + ls=$( ls -ld "$app_path" ) + link=${ls#*' -> '} + case $link in #( + /*) app_path=$link ;; #( + *) app_path=$APP_HOME$link ;; + esac +done + +# This is normally unused +# shellcheck disable=SC2034 +APP_BASE_NAME=${0##*/} +APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit + +# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script. +DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"' + +# Use the maximum available, or set MAX_FD != -1 to use that value. +MAX_FD=maximum + +warn () { + echo "$*" +} >&2 + +die () { + echo + echo "$*" + echo + exit 1 +} >&2 + +# OS specific support (must be 'true' or 'false'). +cygwin=false +msys=false +darwin=false +nonstop=false +case "$( uname )" in #( + CYGWIN* ) cygwin=true ;; #( + Darwin* ) darwin=true ;; #( + MSYS* | MINGW* ) msys=true ;; #( + NONSTOP* ) nonstop=true ;; +esac + +CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar + + +# Determine the Java command to use to start the JVM. +if [ -n "$JAVA_HOME" ] ; then + if [ -x "$JAVA_HOME/jre/sh/java" ] ; then + # IBM's JDK on AIX uses strange locations for the executables + JAVACMD=$JAVA_HOME/jre/sh/java + else + JAVACMD=$JAVA_HOME/bin/java + fi + if [ ! -x "$JAVACMD" ] ; then + die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME + +Please set the JAVA_HOME variable in your environment to match the +location of your Java installation." + fi +else + JAVACMD=java + which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. + +Please set the JAVA_HOME variable in your environment to match the +location of your Java installation." +fi + +# Increase the maximum file descriptors if we can. +if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then + case $MAX_FD in #( + max*) + # In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked. + # shellcheck disable=SC3045 + MAX_FD=$( ulimit -H -n ) || + warn "Could not query maximum file descriptor limit" + esac + case $MAX_FD in #( + '' | soft) :;; #( + *) + # In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked. + # shellcheck disable=SC3045 + ulimit -n "$MAX_FD" || + warn "Could not set maximum file descriptor limit to $MAX_FD" + esac +fi + +# Collect all arguments for the java command, stacking in reverse order: +# * args from the command line +# * the main class name +# * -classpath +# * -D...appname settings +# * --module-path (only if needed) +# * DEFAULT_JVM_OPTS, JAVA_OPTS, and GRADLE_OPTS environment variables. + +# For Cygwin or MSYS, switch paths to Windows format before running java +if "$cygwin" || "$msys" ; then + APP_HOME=$( cygpath --path --mixed "$APP_HOME" ) + CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" ) + + JAVACMD=$( cygpath --unix "$JAVACMD" ) + + # Now convert the arguments - kludge to limit ourselves to /bin/sh + for arg do + if + case $arg in #( + -*) false ;; # don't mess with options #( + /?*) t=${arg#/} t=/${t%%/*} # looks like a POSIX filepath + [ -e "$t" ] ;; #( + *) false ;; + esac + then + arg=$( cygpath --path --ignore --mixed "$arg" ) + fi + # Roll the args list around exactly as many times as the number of + # args, so each arg winds up back in the position where it started, but + # possibly modified. + # + # NB: a `for` loop captures its iteration list before it begins, so + # changing the positional parameters here affects neither the number of + # iterations, nor the values presented in `arg`. + shift # remove old arg + set -- "$@" "$arg" # push replacement arg + done +fi + +# Collect all arguments for the java command; +# * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of +# shell script including quotes and variable substitutions, so put them in +# double quotes to make sure that they get re-expanded; and +# * put everything else in single quotes, so that it's not re-expanded. + +set -- \ + "-Dorg.gradle.appname=$APP_BASE_NAME" \ + -classpath "$CLASSPATH" \ + org.gradle.wrapper.GradleWrapperMain \ + "$@" + +# Stop when "xargs" is not available. +if ! command -v xargs >/dev/null 2>&1 +then + die "xargs is not available" +fi + +# Use "xargs" to parse quoted args. +# +# With -n1 it outputs one arg per line, with the quotes and backslashes removed. +# +# In Bash we could simply go: +# +# readarray ARGS < <( xargs -n1 <<<"$var" ) && +# set -- "${ARGS[@]}" "$@" +# +# but POSIX shell has neither arrays nor command substitution, so instead we +# post-process each arg (as a line of input to sed) to backslash-escape any +# character that might be a shell metacharacter, then use eval to reverse +# that process (while maintaining the separation between arguments), and wrap +# the whole thing up as a single "set" statement. +# +# This will of course break if any of these variables contains a newline or +# an unmatched quote. +# + +eval "set -- $( + printf '%s\n' "$DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS" | + xargs -n1 | + sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' | + tr '\n' ' ' + )" '"$@"' + +exec "$JAVACMD" "$@" diff --git a/gradlew.bat b/gradlew.bat new file mode 100644 index 0000000..93e3f59 --- /dev/null +++ b/gradlew.bat @@ -0,0 +1,92 @@ +@rem +@rem Copyright 2015 the original author or authors. +@rem +@rem Licensed under the Apache License, Version 2.0 (the "License"); +@rem you may not use this file except in compliance with the License. +@rem You may obtain a copy of the License at +@rem +@rem https://www.apache.org/licenses/LICENSE-2.0 +@rem +@rem Unless required by applicable law or agreed to in writing, software +@rem distributed under the License is distributed on an "AS IS" BASIS, +@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +@rem See the License for the specific language governing permissions and +@rem limitations under the License. +@rem + +@if "%DEBUG%"=="" @echo off +@rem ########################################################################## +@rem +@rem Gradle startup script for Windows +@rem +@rem ########################################################################## + +@rem Set local scope for the variables with windows NT shell +if "%OS%"=="Windows_NT" setlocal + +set DIRNAME=%~dp0 +if "%DIRNAME%"=="" set DIRNAME=. +@rem This is normally unused +set APP_BASE_NAME=%~n0 +set APP_HOME=%DIRNAME% + +@rem Resolve any "." and ".." in APP_HOME to make it shorter. +for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi + +@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script. +set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m" + +@rem Find java.exe +if defined JAVA_HOME goto findJavaFromJavaHome + +set JAVA_EXE=java.exe +%JAVA_EXE% -version >NUL 2>&1 +if %ERRORLEVEL% equ 0 goto execute + +echo. +echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. +echo. +echo Please set the JAVA_HOME variable in your environment to match the +echo location of your Java installation. + +goto fail + +:findJavaFromJavaHome +set JAVA_HOME=%JAVA_HOME:"=% +set JAVA_EXE=%JAVA_HOME%/bin/java.exe + +if exist "%JAVA_EXE%" goto execute + +echo. +echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME% +echo. +echo Please set the JAVA_HOME variable in your environment to match the +echo location of your Java installation. + +goto fail + +:execute +@rem Setup the command line + +set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar + + +@rem Execute Gradle +"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %* + +:end +@rem End local scope for the variables with windows NT shell +if %ERRORLEVEL% equ 0 goto mainEnd + +:fail +rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of +rem the _cmd.exe /c_ return code! +set EXIT_CODE=%ERRORLEVEL% +if %EXIT_CODE% equ 0 set EXIT_CODE=1 +if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE% +exit /b %EXIT_CODE% + +:mainEnd +if "%OS%"=="Windows_NT" endlocal + +:omega diff --git a/settings.gradle.kts b/settings.gradle.kts new file mode 100644 index 0000000..3554503 --- /dev/null +++ b/settings.gradle.kts @@ -0,0 +1 @@ +rootProject.name = "appendix" \ No newline at end of file diff --git a/src/main/kotlin/org/bvd/appendix/Aggregate.kt b/src/main/kotlin/org/bvd/appendix/Aggregate.kt new file mode 100644 index 0000000..648eca2 --- /dev/null +++ b/src/main/kotlin/org/bvd/appendix/Aggregate.kt @@ -0,0 +1,10 @@ +package org.bvd.appendix + +import java.util.UUID + +interface Aggregate { + + fun getId(): UUID + + fun applyEvent(event: Event): T +} diff --git a/src/main/kotlin/org/bvd/appendix/Appendix.kt b/src/main/kotlin/org/bvd/appendix/Appendix.kt new file mode 100644 index 0000000..4c10d1f --- /dev/null +++ b/src/main/kotlin/org/bvd/appendix/Appendix.kt @@ -0,0 +1,44 @@ +package org.bvd.appendix + +import com.fasterxml.jackson.databind.ObjectMapper +import java.util.* +import javax.sql.DataSource + +class Appendix { + private val transactionRunner: TransactionRunner + private val eventStore: EventStore + + constructor(dataSource: DataSource) { + this.transactionRunner = TransactionRunner(dataSource) + this.eventStore = EventStore(ObjectMapper().findAndRegisterModules()) + validateConnection(dataSource) + } + + private fun validateConnection(dataSource: DataSource) { + dataSource.connection.use { connection -> + connection.prepareStatement("SELECT version();").use { preparedStatement -> + preparedStatement.executeQuery().use { resultSet -> + while (resultSet.next()) { + println( + "Appendix initialized with connection: ${dataSource.connection.metaData}, database version: ${ + resultSet.getString( + 1 + ) + }" + ) + } + } + } + } + } + + fun appendEvents(streamId: UUID, events: List, expectedVersion: Long) { + transactionRunner.runInTransaction { connection -> + eventStore.append(connection, events, streamId, expectedVersion) + } + } + + fun loadEvents(streamId: UUID): List { + return transactionRunner.runInTransaction { connection -> eventStore.loadEvents(connection, streamId) } + } +} \ No newline at end of file diff --git a/src/main/kotlin/org/bvd/appendix/Event.kt b/src/main/kotlin/org/bvd/appendix/Event.kt new file mode 100644 index 0000000..f89a41c --- /dev/null +++ b/src/main/kotlin/org/bvd/appendix/Event.kt @@ -0,0 +1,3 @@ +package org.bvd.appendix + +interface Event diff --git a/src/main/kotlin/org/bvd/appendix/EventStore.kt b/src/main/kotlin/org/bvd/appendix/EventStore.kt new file mode 100644 index 0000000..bbe61f2 --- /dev/null +++ b/src/main/kotlin/org/bvd/appendix/EventStore.kt @@ -0,0 +1,60 @@ +package org.bvd.appendix + +import com.fasterxml.jackson.databind.ObjectMapper +import java.sql.Connection +import java.time.Instant +import java.util.* + +class EventStore(val mapper: ObjectMapper) { + private companion object { + const val INSERT_EVENTS_SQL: String = + "INSERT INTO events (event_id, stream_id, version, event_type, payload, emitted_at) VALUES (?, ?, ?, ?, ?, ?)" + const val READ_EVENTS_SQL: String = + "SELECT event_id, stream_id, version, event_type, payload, emitted_at FROM events WHERE stream_id = ? ORDER BY version ASC" + } + + fun append( + connection: Connection, + events: List, + streamId: UUID, + expectedVersion: Long + ) { + if (events.isEmpty()) { + return + } + + connection.prepareStatement(INSERT_EVENTS_SQL).use { statement -> + + for (event in events) { + statement.setObject(1, UUID.randomUUID()) + statement.setObject(2, streamId) + statement.setLong(3, expectedVersion + 1) + statement.setString(4, event::class.qualifiedName) + statement.setBytes(5, mapper.writeValueAsBytes(event)) + statement.setObject(6, Instant.now()) + statement.addBatch() + } + } + } + + fun loadEvents(connection: Connection, streamId: UUID): List { + connection.prepareStatement(READ_EVENTS_SQL).use { statement -> + statement.setObject(1, streamId) + + statement.executeQuery().use { resultSet -> + val events = mutableListOf() + + while (resultSet.next()) { + val eventType = resultSet.getString("event_type") + val payloadBytes: ByteArray = resultSet.getBytes("payload") + + val payloadClass = Class.forName(eventType) + + events.add(mapper.readValue(payloadBytes, payloadClass) as Event) + } + + return events + } + } + } +} diff --git a/src/main/kotlin/org/bvd/appendix/TransactionRunner.kt b/src/main/kotlin/org/bvd/appendix/TransactionRunner.kt new file mode 100644 index 0000000..ff9706c --- /dev/null +++ b/src/main/kotlin/org/bvd/appendix/TransactionRunner.kt @@ -0,0 +1,27 @@ +package org.bvd.appendix + +import java.sql.Connection +import javax.sql.DataSource + + +class TransactionRunner(private val dataSource: DataSource) { + + fun runInTransaction(block: (connection: Connection) -> T): T { + dataSource.connection.use { connection -> + connection.autoCommit = false; + connection.transactionIsolation = Connection.TRANSACTION_READ_COMMITTED + + try { + val result = block(connection) + connection.commit() + return result + } catch (e: Exception) { + System.err.println("Transaction failed: $e") + connection.rollback() + throw e + } finally { + connection.close() + } + } + } +} diff --git a/src/test/kotlin/org/bvd/appendix/DataSourceTest.kt b/src/test/kotlin/org/bvd/appendix/DataSourceTest.kt new file mode 100644 index 0000000..07ed79a --- /dev/null +++ b/src/test/kotlin/org/bvd/appendix/DataSourceTest.kt @@ -0,0 +1,61 @@ +package org.bvd.appendix + +import com.zaxxer.hikari.HikariConfig +import com.zaxxer.hikari.HikariDataSource +import org.assertj.core.api.Assertions.assertThat +import org.junit.jupiter.api.Test +import javax.sql.DataSource + +class DataSourceTest { + + @Test + fun test() { + getDataSource().connection.use { connection -> + connection.autoCommit = false + + connection.createStatement().use { st -> + st.execute("create schema if not exists appendix") + st.execute("set search_path to appendix") + } + + connection.prepareStatement( + """create table if not exists test(id serial primary key, name varchar(255) not null)""" + ).use { it.execute() } + + connection.prepareStatement("""insert into test(name) values (?)""").use { ps -> + ps.setString(1, "example name") + ps.executeUpdate() + } + + connection.prepareStatement("""select id, name from test""").use { ps -> + ps.executeQuery().use { rs -> + while (rs.next()) println("id: ${rs.getInt("id")}, name: ${rs.getString("name")}") + } + } + + connection.commit() + } + } + + @Test + fun testAppendixInstantiation() { + val appendix = Appendix(getDataSource()) + assertThat(appendix).isNotNull + } + + fun getDataSource(): DataSource { + val config = HikariConfig().apply { + jdbcUrl = "jdbc:postgresql://localhost:5432/appendix?currentSchema=appendix" + username = "appendix" + password = "appendix_pass" + + maximumPoolSize = 10 + minimumIdle = 2 + connectionTimeout = 30_000 + idleTimeout = 600_000 + maxLifetime = 1_800_000 + } + + return HikariDataSource(config) + } +} \ No newline at end of file