add server to monorepo.

packages/server/src/models/Metable.ts

@@ -0,0 +1,281 @@
+import knex from '@/database/knex';
+// import cache from 'memory-cache';
+
+// Metadata
+export default {
+  METADATA_GROUP: 'default',
+  KEY_COLUMN: 'key',
+  VALUE_COLUMN: 'value',
+  TYPE_COLUMN: 'type',
+
+  extraColumns: [],
+  metadata: [],
+  shouldReload: true,
+  extraMetadataQuery: () => {},
+
+  /**
+   * Set the value column key to query from.
+   * @param {String} name -
+   */
+  setKeyColumnName(name) {
+    this.KEY_COLUMN = name;
+  },
+
+  /**
+   * Set the key column name to query from.
+   * @param {String} name -
+   */
+  setValueColumnName(name) {
+    this.VALUE_COLUMN = name;
+  },
+
+  /**
+   * Set extra columns to be added to the rows.
+   * @param {Array} columns -
+   */
+  setExtraColumns(columns) {
+    this.extraColumns = columns;
+  },
+
+  /**
+   * Metadata database query.
+   * @param {Object} query -
+   * @param {String} groupName -
+   */
+  whereQuery(query, key) {
+    const groupName = this.METADATA_GROUP;
+
+    if (groupName) {
+      query.where('group', groupName);
+    }
+    if (key) {
+      if (Array.isArray(key)) {
+        query.whereIn('key', key);
+      } else {
+        query.where('key', key);
+      }
+    }
+  },
+
+  /**
+   * Loads the metadata from the storage.
+   * @param {String|Array} key -
+   * @param {Boolean} force -
+   */
+  async load(force = false) {
+    if (this.shouldReload || force) {
+      const metadataCollection = await this.query((query) => {
+        this.whereQuery(query);
+        this.extraMetadataQuery(query);
+      }).fetchAll();
+
+      this.shouldReload = false;
+      this.metadata = [];
+
+      const metadataArray = this.mapMetadataCollection(metadataCollection);
+      metadataArray.forEach((metadata) => { this.metadata.push(metadata); });
+    }
+  },
+
+  /**
+   * Fetches all the metadata that associate with the current group.
+   */
+  async allMeta(force = false) {
+    await this.load(force);
+    return this.metadata;
+  },
+
+  /**
+   * Find the given metadata key.
+   * @param {String} key -
+   * @return {object} - Metadata object.
+   */
+  findMeta(key) {
+    return this.metadata.find((meta) => meta.key === key);
+  },
+
+  /**
+   * Fetch the metadata of the current group.
+   * @param {*} key -
+   */
+  async getMeta(key, defaultValue, force = false) {
+    await this.load(force);
+
+    const metadata = this.findMeta(key);
+    return metadata ? metadata.value : defaultValue || false;
+  },
+
+  /**
+   * Markes the metadata to should be deleted.
+   * @param {String} key -
+   */
+  async removeMeta(key) {
+    await this.load();
+    const metadata = this.findMeta(key);
+
+    if (metadata) {
+      metadata.markAsDeleted = true;
+    }
+    this.shouldReload = true;
+  },
+
+  /**
+   * Remove all meta data of the given group.
+   * @param {*} group
+   */
+  removeAllMeta(group = 'default') {
+    this.metdata.map((meta) => ({
+      ...(meta.group !== group) ? { markAsDeleted: true } : {},
+      ...meta,
+    }));
+    this.shouldReload = true;
+  },
+
+  /**
+   * Set the meta data to the stack.
+   * @param {String} key -
+   * @param {String} value -
+   */
+  async setMeta(key, value, payload) {
+    if (Array.isArray(key)) {
+      const metadata = key;
+      metadata.forEach((meta) => {
+        this.setMeta(meta.key, meta.value);
+      });
+      return;
+    }
+
+    await this.load();
+    const metadata = this.findMeta(key);
+
+    if (metadata) {
+      metadata.value = value;
+      metadata.markAsUpdated = true;
+    } else {
+      this.metadata.push({
+        value, key, ...payload, markAsInserted: true,
+      });
+    }
+  },
+
+  /**
+   * Saved the modified metadata.
+   */
+  async saveMeta() {
+    const inserted = this.metadata.filter((m) => (m.markAsInserted === true));
+    const updated = this.metadata.filter((m) => (m.markAsUpdated === true));
+    const deleted = this.metadata.filter((m) => (m.markAsDeleted === true));
+
+    const metadataDeletedKeys = deleted.map((m) => m.key);
+    const metadataInserted = inserted.map((m) => this.mapMetadata(m, 'format'));
+    const metadataUpdated = updated.map((m) => this.mapMetadata(m, 'format'));
+
+    const batchUpdate = (collection) => knex.transaction((trx) => {
+      const queries = collection.map((tuple) => {
+        const query = knex(this.tableName);
+        this.whereQuery(query, tuple.key);
+        this.extraMetadataQuery(query);
+        return query.update(tuple).transacting(trx);
+      });
+      return Promise.all(queries).then(trx.commit).catch(trx.rollback);
+    });
+
+    await Promise.all([
+      knex.insert(metadataInserted).into(this.tableName),
+      batchUpdate(metadataUpdated),
+      metadataDeletedKeys.length > 0
+        ? this.query('whereIn', this.KEY_COLUMN, metadataDeletedKeys).destroy({
+          require: true,
+        }) : null,
+    ]);
+    this.shouldReload = true;
+  },
+
+  /**
+   * Purge all the cached metadata in the memory.
+   */
+  purgeMetadata() {
+    this.metadata = [];
+    this.shouldReload = true;
+  },
+
+  /**
+   * Parses the metadata value.
+   * @param {String} value -
+   * @param {String} valueType -
+   */
+  parseMetaValue(value, valueType) {
+    let parsedValue;
+
+    switch (valueType) {
+      case 'integer':
+        parsedValue = parseInt(value, 10);
+        break;
+      case 'float':
+        parsedValue = parseFloat(value);
+        break;
+      case 'boolean':
+        parsedValue = Boolean(value);
+        break;
+      case 'json':
+        parsedValue = JSON.parse(parsedValue);
+        break;
+      default:
+        parsedValue = value;
+        break;
+    }
+    return parsedValue;
+  },
+
+  /**
+   * Format the metadata before saving to the database.
+   * @param {String|Number|Boolean} value -
+   * @param {String} valueType -
+   * @return {String|Number|Boolean} -
+   */
+  formatMetaValue(value, valueType) {
+    let parsedValue;
+
+    switch (valueType) {
+      case 'number':
+        parsedValue = `${value}`;
+        break;
+      case 'boolean':
+        parsedValue = value ? '1' : '0';
+        break;
+      case 'json':
+        parsedValue = JSON.stringify(parsedValue);
+        break;
+      default:
+        parsedValue = value;
+        break;
+    }
+    return parsedValue;
+  },
+
+  mapMetadata(attr, parseType = 'parse') {
+    return {
+      key: attr[this.KEY_COLUMN],
+      value: (parseType === 'parse')
+        ? this.parseMetaValue(
+          attr[this.VALUE_COLUMN],
+          this.TYPE_COLUMN ? attr[this.TYPE_COLUMN] : false,
+        )
+        : this.formatMetaValue(
+          attr[this.VALUE_COLUMN],
+          this.TYPE_COLUMN ? attr[this.TYPE_COLUMN] : false,
+        ),
+      ...this.extraColumns.map((extraCol) => ({
+        [extraCol]: attr[extraCol] || null,
+      })),
+    };
+  },
+
+  /**
+   * Parse the metadata collection.
+   * @param {Array} collection -
+   */
+  mapMetadataCollection(collection, parseType = 'parse') {
+    return collection.map((model) => this.mapMetadata(model.attributes, parseType));
+  },
+};