A minimal IndexedDB wrapper for ClojureScript
To install, add the following to your project :dependencies:
[g7s/aye-db "0.1.0"]
NOTE: This library uses promises to create a better API for IndexedDB (which uses callbacks).
To start just create a database instance as such:
(ns my.app.database
(:require
[g7s.aye-db :as idb]))
(def db
(idb/new-idb {:name "mydb"
:version 2
:on-upgrade
(fn [e]
(let [ndb (.-result (.-target e))
oldv (.-oldVersion e)]
(when (< oldv 1)
(.createObjectStore ndb "objects"))
(when (< oldv 2)
(.createObjectStore ndb "other-objects"))))}))One can execute queries against this database using the with-tx macro that is of the form
(with-tx db exec-fn-symbol & body)where db is the database instance that you created, the exec-fn-symbol is a symbol that you have
to use inside the body to execute queries (it can be anything you like) and represents a function with
a signature:
(exec-fn-symbol [object-store [query-type & args]])where object-store is the string name of the object store that you are querying against and query-type
is a keyword (e.g. :idb/get) and args are data that are needed by the query-type. The mapping of
query type keyword to the native IndexedDB method is:
| query type | IndexedDB |
|---|---|
:idb/get |
IDBObjectStore.get() |
:idb/get-all |
IDBObjectStore.getAll() |
:idb/get-key |
IDBObjectStore.getKey() |
:idb/get-all-keys |
IDBObjectStore.getAllKeys() |
:idb/cursor |
IDBObjectStore.openCursor() |
:idb/key-cursor |
IDBObjectStore.openKeyCursor() |
:idb/index |
IDBObjectStore.index() |
:idb/count |
IDBObjectStore.count() |
:idb/put |
IDBObjectStore.put() |
:idb/add |
IDBObjectStore.add() |
:idb/delete |
IDBObjectStore.delete() |
:idb/clear |
IDBObjectStore.clear() |
NOTE: The :idb/index query accepts only two arguments; the name of the index to open and a query to run on the index e.g.
(exec-fn-symbol ["users" [:idb/index "by-name" [:idb/get "John"]]])Because some queries accept a key range instead of just a key, aye-db exposes functions for constructing key ranges:
| aye-db | IndexedDB constructor | Meaning |
|---|---|---|
(r<= x) |
IDBKeyRange.upperBound(x) | All keys ≤ x |
(r< x) |
IDBKeyRange.upperBound(x, true) | All keys < x |
(r>= y) |
IDBKeyRange.lowerBound(y) | All keys ≥ y |
(r> y) |
IDBKeyRange.lowerBound(y, true) | All keys > y |
(r>=<= x y) |
IDBKeyRange.bound(x, y) | All keys ≥ x && ≤ y |
(r><= x y) |
IDBKeyRange.bound(x, y, true, false) | All keys > x && ≤ y |
(r>=< x y) |
IDBKeyRange.bound(x, y, false, true) | All keys ≥ x && < y |
(r>< x y) |
IDBKeyRange.bound(x, y, true, true) | All keys > x && < y |
(r= x) |
IDBKeyRange.only(x) | All keys = x |
An example usage of with-tx is the following
(require '[promesa.core :as p])
(with-tx db exec!
(p/let [fk "a/path"
tk "another/path"
file (exec! ["files" [:idb/get fk]])]
(exec! ["files" [:idb/delete fk]])
(exec! ["files" [:idb/put file tk]])))Copyright © 2020 Gerasimos
This program and the accompanying materials are made available under the terms of the Eclipse Public License 2.0 which is available at http://www.eclipse.org/legal/epl-2.0.
This Source Code may also be made available under the following Secondary Licenses when the conditions for such availability set forth in the Eclipse Public License, v. 2.0 are satisfied: GNU General Public License as published by the Free Software Foundation, either version 2 of the License, or (at your option) any later version, with the GNU Classpath Exception which is available at https://www.gnu.org/software/classpath/license.html.