+ draft about ParrotStore

drafts/parrotstore.md

@@ -0,0 +1,71 @@
+---
+layout: post
+categories: [Parrot, ParrotStore]
+title: ParrotStore
+---
+
+I created a new repo for a new project: ParrotStore. ParrotStore intends to
+provide some storage and persistance (and caching and database) solutions for
+Parrot.
+
+## Memcached
+
+The first thing I've written is a rudimentary interface to Memcached for
+high speed caching. The interface looks like this:
+
+    var memcached = new ParrotStore.Memcached(["192.168.1.1", "192.169.1.2"]);
+    memcached.set("foo", "hello world!");
+    :(int have, string content) = memcached.get("foo");
+    say(content);
+
+Or, if you want a simpler interface, you can do something like this:
+
+    string content = memcached.autoget("foo",
+        function() { return "hello world!"; }
+    );
+
+The `autoget` method will try to read from Memcached if the item exists, and
+will invoke the callback to get the value otherwise (and save it to Memcached
+for later use). Of course, for this to be practical the callback to generate
+the content should be more expensive than a return of a constant string.
+
+Memcached is easy, so I started working on it first. Other projects won't be
+quite so easy.
+
+## Future Projects
+
+The goal of ParrotStore is simple persistance. In a sense it might become
+something like an ORM, mapping Parrot data to and from various persistance
+mechanisms. This project does not intend to do any embedding, whether Parrot
+embedded in a database or a database embedded in Parrot, or whatever else. The
+Database (or cache or whatever) is separate, and ParrotStore just provides an
+interface to it. For instance, the PL/Parrot project embeds Parrot into the
+Postgres DB. ParrotStore would provide an external interface for querying it.
+
+Two other things I want to add in the future are interfaces for MySQL and
+MongoDB. These things are probably going to want to be implemented at the C
+level through wrapper PMCs, but I haven't settled on a design yet. Once we have
+these things and some kind of presence on the web (a revamped ModParrot or
+FastCGI bindings seem like good options right now), creating real websites
+running on Parrot starts to become a reality.
+
+I also want to add a custom caching mechanism for storing frozen PMCs to file
+and fetching them again. Multiple backends to a PMC mechanism would allow us
+to store PMCs to various persistance systems for later use. This is another
+thing that I've wanted for a while, but I haven't quite nailed down a design
+yet.
+
+## ParrotStore Architecture
+
+Like Rosella, which is a prerequisite for this project, ParrotStore will be a
+collection of things, not one big monolithic system. It will provide a
+Memcached interface in one standalone library, and will provide other things as
+separate libraries too. Some of them (like Memcached) will be pure parrot. Other
+things like MongoDB might have C-level components too. Where Rosella has always
+promised to be pure Parrot, ParrotStore cannot and should not follow such a
+rule.
+
+The first thing I need to do now is set up a proper build system and a test
+suite. Then I want to start adding new things. It's actually exciting to think
+about all the cool new things we'll
+