refactor: Match databases dir to namespace.

src/databases/documents.js

@@ -0,0 +1,163 @@
+/**
+ * @namespace Databases-Documents
+ * @memberof module:Databases
+ * @description Documents database.
+ * @example <caption>Create documents db with default options</caption>
+ * import { create } from 'IPFS'
+ *
+ * const ipfs = create()
+ * const Partial = Documents()
+ * const documents = await Partial({ ipfs })
+ * @example <caption>Create documents db with custom index</caption>
+ * import { create } from 'IPFS'
+ *
+ * const ipfs = create()
+ * const options = { indexBy: 'myCustomId'}
+ * const Partial = Documents(options)
+ * const documents = await Partial({ ipfs })
+ */
+import Database from '../database.js'
+
+const DefaultOptions = { indexBy: '_id' }
+
+/**
+ * Defines a Documents database.
+ * @param {Object} options Various options for configuring the Document store.
+ * @param {string} [params.indexBy=_id] An index.
+ * @return {module:Databases.Databases-Documents} A Documents function.
+ * @memberof module:Databases
+ */
+const Documents = ({ indexBy } = DefaultOptions) => async ({ ipfs, identity, address, name, access, directory, meta, headsStorage, entryStorage, indexStorage, referencesCount, syncAutomatically, onUpdate }) => {
+  const database = await Database({ ipfs, identity, address, name, access, directory, meta, headsStorage, entryStorage, indexStorage, referencesCount, syncAutomatically })
+
+  const { addOperation, log } = database
+
+  /**
+   * Stores a document to the store.
+   * @function
+   * @param {Object} doc An object representing a key/value list of fields.
+   * @return {string} The hash of the new oplog entry.
+   * @memberof module:Databases.Databases-Documents
+   * @instance
+   */
+  const put = async (doc) => {
+    const key = doc[indexBy]
+
+    if (!key) { throw new Error(`The provided document doesn't contain field '${indexBy}'`) }
+
+    return addOperation({ op: 'PUT', key, value: doc })
+  }
+
+  /**
+   * Deletes a document from the store.
+   * @function
+   * @param {string} key The key of the doc to delete.
+   * @return {string} The hash of the new oplog entry.
+   * @memberof module:Databases.Databases-Documents
+   * @instance
+   */
+  const del = async (key) => {
+    if (!await get(key)) { throw new Error(`No document with key '${key}' in the database`) }
+
+    return addOperation({ op: 'DEL', key, value: null })
+  }
+
+  /**
+   * Gets a document from the store by key.
+   * @function
+   * @param {string} key The key of the doc to get.
+   * @return {Object} The doc corresponding to key or null.
+   * @memberof module:Databases.Databases-Documents
+   * @instance
+   */
+  const get = async (key) => {
+    for await (const doc of iterator()) {
+      if (key === doc.key) {
+        return doc
+      }
+    }
+  }
+
+  /**
+   * Queries the document store for documents matching mapper filters.
+   * @function
+   * @param {function(Object)} findFn A function for querying for specific
+   * results.
+   *
+   * The findFn function's signature takes the form `function(doc)` where doc
+   * is a document's value property. The function should return true if the
+   * document is found, false otherwise.
+   * @return {Array} Found documents.
+   * @memberof module:Databases.Databases-Documents
+   * @instance
+   */
+  const query = async (findFn) => {
+    const results = []
+
+    for await (const doc of iterator()) {
+      if (findFn(doc.value)) {
+        results.push(doc.value)
+      }
+    }
+
+    return results
+  }
+
+  /**
+   * Iterates over documents.
+   * @function
+   * @param {Object} [filters={}] Various filters to apply to the iterator.
+   * @param {string} [filters.amount=-1] The number of results to fetch.
+   * @yields [string, string, string] The next document as hash/key/value.
+   * @memberof module:Databases.Databases-Documents
+   * @instance
+   */
+  const iterator = async function * ({ amount } = {}) {
+    const keys = {}
+    let count = 0
+    for await (const entry of log.iterator()) {
+      const { op, key, value } = entry.payload
+      if (op === 'PUT' && !keys[key]) {
+        keys[key] = true
+        count++
+        const hash = entry.hash
+        yield { hash, key, value }
+      } else if (op === 'DEL' && !keys[key]) {
+        keys[key] = true
+      }
+      if (count >= amount) {
+        break
+      }
+    }
+  }
+
+  /**
+   * Returns all documents.
+   * @function
+   * @return [][string, string, string] An array of documents as hash/key
+   * value entries.
+   * @memberof module:Databases.Databases-Documents
+   * @instance
+   */
+  const all = async () => {
+    const values = []
+    for await (const entry of iterator()) {
+      values.unshift(entry)
+    }
+    return values
+  }
+
+  return {
+    ...database,
+    type: 'documents',
+    put,
+    del,
+    get,
+    iterator,
+    query,
+    indexBy,
+    all
+  }
+}
+
+export default Documents