#!/bin/bash
-# Copyright (C) 2005-2016 by the Quassel Project - devel@quassel-irc.org
+# Copyright (C) 2005-2019 by the Quassel Project - devel@quassel-irc.org
# Licensed under GNU General Public License version 2, or (at your option)
# version 3.
#
-# "One does not simply 'upgrade the schema'..."
+# Call this script whenever you need to add a new database schema version.
+# You can also simply create a new folder in '[SQLite/PostgreSQL]/version/##',
+# where '##' represents your new version number, incremented by one from
+# whatever the current latest version is (e.g. 21 -> 22).
#
-# When changing Quassel's database schema, you need to follow several steps to
-# handle all cases (upgrade, Postgres migration, etc).
-#
-# 1. Run this script on -both- the PostgreSQL and SQLite directory
-#
-# Make sure you're on the Git branch you want to modify
-# > ./upgradeSchema.sh "PostgreSQL"
-# > ./upgradeSchema.sh "SQLite"
-#
-# 2. Modify queries and setup scripts to handle your change
-#
-# [Example] Modifying the 'ircserver' table to add column 'test'
-# Modify all query/setup .sql files that touch the 'ircserver' table for
-# -both- PostgreSQL and SQLite.
-#
-# 3. Create an upgrade script for -both- PostgreSQL and SQLite
-#
-# [Example] Modifying the 'ircserver' table to add column 'test'
-# Add the file 'upgrade_000_alter_ircserver_add_test.sql' with contents:
-# > ALTER TABLE ircserver
-# > ADD COLUMN test [additional column-specific details]
-#
-# 4. Create a pair of migration scripts for moving from SQLite to PostgreSQL
-#
-# [Example] Modifying the 'ircserver' table to add column 'test'
-# > Modify 'SQLite/##/migrate_read_ircserver.sql' to select from new column
-# > Modify 'PostgreSQL/##/migrate_write_ircserver.sql' to insert to new column
-#
-# 5. Add the new SQL queries to 'src/core/sql.qrc', update all existing files
-#
-# You may need to re-run CMake to detect these changes.
-#
-# [Example] Modifying the 'ircserver' table to add column 'test'
-# > Add the new upgrade script...
-# <file>./SQL/SQLite/19/upgrade_000_alter_ircserver_add_test.sql</file>
-# <file>./SQL/PostgreSQL/18/upgrade_000_alter_ircserver_add_test.sql</file>
-# > Find/replace all non-upgrade scripts from the old schema number to new one
-# <file>./SQL/SQLite/[18->19]/update_buffer_persistent_channel.sql</file>
-# <file>./SQL/PostgreSQL/[17->18]/update_buffer_persistent_channel.sql</file>
-# (etc)
-#
-# 6. Update the migration logic in 'src/core/abstractsqlstorage.h', and the
-# storage backends 'postgresqlstorage.cpp' and 'sqlitestorage.cpp'
-#
-# [Example] Modifying the 'ircserver' table to add column 'test'
-# > Modify struct 'IrcServerMO' in 'abstractsqlstorage.h', adding an entry for
-# 'test' of the appropriate data-type.
-# > Modify 'SqliteMigrationReader::readMo(IrcServerMO &ircserver)' in
-# 'sqlitestorage.cpp' to read from the new column and store it in the
-# migration object. You may need to convert from SQLite's looser types.
-# > Modify 'PostgreSqlMigrationWriter::writeMo(const IrcServerMO &ircserver)'
-# in 'postgresqlstorage.cpp' to write to the new column from the data in the
-# migration object.
-#
-# 7. Update any affected queries in storage backends 'postgresqlstorage.cpp'
-# and 'sqlitestorage.cpp', and any related synchronized 'src/common' classes.
-#
-# [Example] Modifying the 'ircserver' table to add column 'test'
-# > Update 'network.h' to add new column to Server structure
-# QString proxyPass; // Existing code
-# Typename test; // New column 'test'
-# [...]
-# Server() : port(6667), ..., proxyPort(8080), test("defaultValue") {}
-# > Modify reading data in ____Storage::networks(...)
-# server.proxyPass = serversQuery.value(10).toString(); // Existing code
-# server.test = serversQuery.value(11).toType(); // New column 'test'
-# servers << server; // Existing code
-# > Modify writing data in ____Storage::bindServerInfo(...)
-# query.bindValue(":proxypass", server.proxyPass); // Existing code
-# query.bindValue(":test", server.test); // New column 'test'
-#
-# 8. If protocol changed (add a setting, etc), add a new "Feature" flag
-#
-# Newer clients need to detect when they're on an older core to disable the
-# feature. Use 'enum Feature' in 'quassel.h'. In client-side code, test with
-# 'if (Client::coreFeatures() & Quassel::FeatureName) { ... }'
-#
-# 9. Test everything! Upgrade, migrate, new setups, new client/old core,
-# old client/new core, etc.
+# NOTE: If you upgrade the database schema version, you must add upgrade
+# scripts and modify the existing setup queries, then regenerate sql.qrc with
+# 'updateSQLResource'. See 'README.md' for details.
TARGET_DIR="$1"
# If not specified, assume current directory
fi
if [[ ! -d "$TARGET_DIR" ]]; then
- echo "No such directory '$TARGET_DIR'"
+ echo "No such directory '$TARGET_DIR'" >&2
exit 1
fi
-cd "$TARGET_DIR"
+# Find out the name of the target directory to offer some guidance later.
+TARGET_DB_NAME=$(basename "$TARGET_DIR")
+
+# Upgrade scripts are stored in the 'version' subdirectory, e.g.
+# 'SQL/[database]/version/##'.
+cd "$TARGET_DIR/version"
# Grab the current schema version
CURRENT_VERSION=$(ls | sort -n | tail -n1)
if [ ! $CURRENT_VERSION ]; then
- echo "No previous schema found to upgrade from"
+ echo "No previous schema found to upgrade from" >&2
exit 2
fi
# Increment by one
((NEW_VERSION=$CURRENT_VERSION + 1))
-# Create the new schema directory, add the directory, and move all files over...
+# Create the new schema directory.
mkdir "$NEW_VERSION"
-git add "$NEW_VERSION"
-# ...except for 'upgrade_' scripts.
-find "$CURRENT_VERSION" -maxdepth 1 -type f \! -name "upgrade_*" \! -name ".*" -exec git mv {} "$NEW_VERSION" \;
+# Git doesn't track empty folders, no need for 'git add "$NEW_VERSION"'.
+
+echo "New schema version '$TARGET_DB_NAME/version/$NEW_VERSION' created." >&2
+echo "Create any needed 'upgrade_[...].sql' scripts in this folder." >&2
+
+# Don't move any files over. Schema version upgrade scripts are now stored
+# independently of the main SQL files in order to make the repository history
+# more useful and easier to work with.
+
+# Granted, this script doesn't do anything one couldn't easily manually do.
+# I'd argue that's a good thing. Though as this script offers documentation
+# and guidance for contributors new to the database schema system as well as
+# helping migrate those used to the older method, it seems worthwhile keeping.
projects / quassel.git / blobdiff