Clean master commit

src/lib/Fetcher.js

@@ -0,0 +1,132 @@
+// FetcherTwo class interfaces with Google Sheet, and saves to a specified db
+import {google} from "googleapis";
+import {fmtSourceTitle, fmtBlueprinterTitles, deriveFilename, bp} from "./util";
+import {byRow, byId} from "./blueprinters";
+import R from "ramda";
+
+class Fetcher {
+  constructor(db, sourceName, sourceId, blueprinters) {
+    /*
+     * The database that the fetcher should use. This should be an instance of a model-compliant class.
+     * See models/Interface.js for the specifications for a model-compliant class.
+     */
+    this.db = db;
+
+    /*
+     * ID of the Google Sheet where the data is sourced. Note that the privateKey.client_email
+     * loaded here must be added to the sheet as an editor.
+     */
+    this.sourceId = sourceId;
+
+    /*
+     * The name of the source. This will prefix tabs saved in the database.
+     */
+    this.sourceName = sourceName;
+
+    /*
+     * These are the available tabs for storing and retrieving data.
+     * Each blueprinter is a function that returns a Blueprint from a
+     * list of lists (which will be retrieved from gsheets).
+     */
+    this.blueprinters = fmtBlueprinterTitles(blueprinters);
+    this.blueprints = {};
+    Object.keys(this.blueprinters).forEach(key => {
+      this.blueprints[key] = null;
+    });
+
+    /*
+     * Google API setup
+     */
+    this.sheets = google.sheets("v4");
+    this.auth = null;
+  }
+
+  /** returns a Promise that resolves if access is granted to the account, and rejects otherwise. */
+  authenticate(client_email, private_key) {
+    const googleAuth = new google.auth.JWT(client_email, null, private_key, [
+      "https://www.googleapis.com/auth/spreadsheets"
+    ]);
+    this.auth = googleAuth;
+    const {sourceId} = this;
+
+    return new Promise((resolve, reject) => {
+      googleAuth.authorize(function(err, tokens) {
+        if (err) {
+          reject(err);
+          return;
+        } else {
+          resolve(`Connected to ${sourceId}.`);
+        }
+      });
+    });
+  }
+
+  update() {
+    let tabTitles;
+    /* Retrieve all available routes on a given sheet, and store formatted copies of it where a formatter is available */
+    return this.sheets.spreadsheets
+      .get({
+        auth: this.auth,
+        spreadsheetId: this.sourceId
+      })
+      .then(response => {
+        tabTitles = response.data.sheets.map(sheet => sheet.properties.title);
+        return this.sheets.spreadsheets.values.batchGet({
+          auth: this.auth,
+          spreadsheetId: this.sourceId,
+          ranges: tabTitles
+        });
+      })
+      .then(results => {
+        const tabData = results.data.valueRanges;
+        return Promise.all(
+          tabData.map((tab, idx) => {
+            const {values} = tab;
+            if (values == undefined) {
+              return Promise.resolve({});
+            }
+            const name = tabTitles[idx];
+            return this.save(name, values);
+          })
+        );
+      })
+      .then(() => "All tabs updated");
+  }
+
+  save(tab, data) {
+    const title = fmtSourceTitle(tab);
+    if (Object.keys(this.blueprinters).indexOf(title) > -1) {
+      const blueprinters = this.blueprinters[title];
+
+      return blueprinters.map(blueprinter => {
+        const saturatedBp = blueprinter(
+          tab,
+          this.sourceName,
+          this.sourceId,
+          data
+        );
+        const blueprint = bp(saturatedBp); // TODO: come up with better semantics.
+        this.blueprints[title] = blueprint;
+        return this.db.save(saturatedBp);
+      });
+    } else {
+      // If it can't find a blueprinter for the tab title, default to byRow
+      return this.db.save(byRow(tab, this.sourceName, this.sourceId, data));
+    }
+  }
+
+  // NB: could combine these functions by checking kwargs length
+  retrieve(tab, resource) {
+    const title = fmtSourceTitle(tab);
+    const url = `${this.sourceName}/${tab}/${resource}`;
+    return this.db.load(url, this.blueprints[title]);
+  }
+
+  retrieveFrag(tab, resource, frag) {
+    const title = fmtSourceTitle(tab);
+    const url = `${this.sourceName}/${tab}/${resource}/${frag}`;
+    return this.db.load(url, this.blueprints[title]);
+  }
+}
+
+export default Fetcher;