oook
2017-11-30
Some magic on the shoulders of CLSQL
OOOK!
OOOK
is some data manipulation magic on top of the venerable CL-SQL
package, which has been providing a solid SQL abstraction in Common Lisp for
years.
The goal of OOOK
is to greatly decrease "standard" database-driven web
application development time with the trade-off of slightly less flexiblity.
With that in mind, some of the features include:
- Clean data "model" (table) definitions
- Automatic handling of model associations (joins) during save / delete
- Serialisation / deserialisation of models for serving as JSON or building from POST data
- HTML generation for data viewing (tables) and editing (forms)
Note: Database design should be driven by the data, not by the code that
uses it! To encourage this, OOOK
will never have functionality to manipulate
the database schema.
Also, OOOK
is still under development and the API is changing fairly
frequently. It is regularly used in its present state, however, and is mostly
stable.
Overview
Create models of tables in the database with defmodel
:
(oook:defmodel post (:belongs-to user) "Some interesting prose, full of wisdom" (date_published :type clsql:wall-time) (title :column "post-title") content) (oook:defmodel user (:has-many posts) "Someone who writes posts" name (level :type integer :documentation "Skill level"))
This creates two CLOS classes which model the "post" and "user" database tables, including the relationship between the two. The models have brief dostrings, custom slots (including types) and associations with other models.
Note: the defmodel
macro creates two CLSQL
view-classes, using
clsql:def-view-class
, containing the specified slots and a number of
additional slots for managing the joins.
Example Workflow:
Create a new user using the standard CLOS make-instance
:
(defvar wizzard (make-instance 'user :name "Rincewind" :level 0))
Create a new post and add it to the user:
(push (posts wizzard) (make-instance 'post :title "On Staying Alive")))
Save the new user (and post) in the database:
(oook:save wizzard) ; Will save both the user and his post
Find something, either by ID with the built-in find-by-id
helper, or construct
a CLSQL
statement for more complex queries (OOOK
provides a few other
helpers, see the documentation).
(oook:find-by-id 'post 2) ; Find the post row with ID == 2 (clsql:select 'user) ; Select all users
POST/JSON serialisation
OOOK
makes it simple to build a model instance given a set of POST data, as
long as the POST data is constructed according to a few rules. If you use the
HTML generation helpers below, this is handled automatically!
More documentation coming soon... But have a look at serialise.lisp
!
HTML Generation
OOOK provides some utilties for viewing and editing model data. In the simplest form, you can generate an HTML form to modify a model with a few lines:
(let ((the-post (make-instance 'post :title "New Post"))) (oook:get-edit-form the-post "/save"))
With the previous definition of post
, this returns the following HTML.
<form class="ui form" action=/save method=POST> <div class=field> <label>Content</label> <input type=text name=post[content]> </div> <div class=field> <label>Title</label> <input type=text name=post[title] value="New Post"> </div> <div class=field> <label>Date_Published</label> <input type=date name=post[date_published]> </div> <div class=field> <label>User Id</label> <input type=number name=post[user_id]> </div> <button class="ui primary button" type=submit>Save</button> </form>
Things to note
- An instance of
post
is passed in, and its values used to pre-populate the form - The field names are compatible with the
OOOK
serialisation functions - This "quick" helper generates fairly minimal HTML - if you want something fancier, use the other helpers below!
Custom Built Forms
OOOK
provides a context manager, with-record-type
to make it easier to build
custom forms.
Documentation coming soon... But have a look at html.lisp
!
Utilities
Enhanced printing
Use oook:def-enhanced-printer
to quickly enhance the printed representations
of models.
CL-USER> (oook:def-enhanced-printer post :slot 'title) ... CL-USER> (format t (oook:find-by-id 'post 5)) #<POST "The Joys of Boredom">
Models Implementation Notes
Overview
Like another well known library, all tables are expected to have at least these three columns:
id
: A unique (for this model type) ID for the row (the table's primary key)created-at
: Time of creationlast-modified
: Time of last modification
These have historically been found to be useful in typical web applications. The
id
field is always required, and will be an index into the table. The second
two can be disabled by passing :timestamped nil
to defmodel
.
In addition, models you define will typically have a number of other fields, corresponding to columns in the table, and possibly a number of associated models.
Associated models
A model can be associated to other models in a number of ways.
- belongs-to
- has-one
- owns-one
- owns-many
Models are selected exactly as you would with CL-SQL
, and, by default, the
joins are lazily loaded (i.e. a "join" slot is only populated from the DB when
it is accessed).
The fun part is saving.
oook:save
will save any associated models that belong to the instance it is
called with. New rows will be created as necessary.
has-one (FK in Left)
Left requires one instance of Right, but Right doesn't care or know about this relationship. (e.g. ingredient -> unit).
- Get: get the relevant Right and merge it into Left
- Save: only save the reference to Right
- Delete: do nothing with Right
owns-one (FK in right) - use with belongs-to (blargh redundancy)
Left owns one Right, and Right knows it. Left cannot have more than one Right. (e.g. user <- config)
- Get: get the Right and merge into Left
- Save: update Right with any changes, ensure reference (ID) has not changed
- Delete: delete right as well
belongs-to (FK in Left) - use with owns-many or owns-one
Left is owned by one Right. Left cannot have more than one owner. (e.g. config <- user). However Right might have more than one Left (e.g. step* <- recipe)
- Get: do not try to resolve the parent relation (circular dep)
- Save: ensure the reference to Right has not changed
- Delete: do nothing
owns-many (FK in Right) - use with belongs-to
Left has many Rights, and the Rights know which Left they belong to. (e.g. recipe <- step*)
- Get: Find all Right that match Left's ID
- Save: Save new Rights in Left, delete old Rights no longer in Left
- Delete: delete all rights as well
many-to-many (intersection table)
Not implemented yet
Left references many instances of Right, and Right might be referenced by many instances of Left. (e.g. programmer <-> project, a programmer is part of many projects and a project has many programmers)
Get: do not try to resolve the parent relation (circular dep)
LICENSE
MIT License
Copyright (c) 2017 Ricardo M. H. da Silva
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.