This is very much a draft/brainstorm right now. It should be made prettier and thought about in more detail later, but it at least gives some idea of the direction we're headed right now. ---- * Two distinct tools; should not be coupled (can work independently): * Versioning tool * Command line tool; let's call it "samigrate" * Organizes old migration scripts into repositories * Runs groups of migration scripts on a database, updating it to a specified version/latest version * Helps run various tests * usage * "samigrate create PATH": Create project migration-script repository * We shouldn't have to enter the path for every other command. Use a hidden file * (This means we can't move the repository after it's created. Oh well) * "samigrate add SCRIPT [VERSION]": Add script to this project's repository; latest version * If a .sql script: how to determine engine, operation (up/down)? Options: * specify at the command line: "samigrate add SCRIPT UP_OR_DOWN ENGINE" * naming convention: SCRIPT is named something like NAME.postgres.up.sql * "samigrate upgrade CONNECTION_STRING [VERSION] [SCRIPT...]": connect to the specified database and upgrade (or downgrade) it to the specified version (default latest) * If SCRIPT... specified: act like these scripts are in the repository (useful for testing?) * "samigrate dump CONNECTION_STRING [VERSION] [SCRIPT...]": like update, but sends all sql to stdout instead of the db * (Later: some more commands, to be used for script testing tools) * Alchemy API extensions for altering schema * Operations here are DB-independent * Each database modification is a script that may use this API * Can handwrite SQL for all databases or a single database * upgrade()/downgrade() functions: need only one file for both operations * sql scripts reqire either (2 files, *.up.sql;*.down.sql) or (don't use downgrade) * usage * "python NAME.py ENGINE up": upgrade sql > stdout * "python NAME.py ENGINE down": downgrade sql > stdout