first commit

plugins/postgresql/handle.js

@@ -0,0 +1,114 @@
+const _ = require('lodash');
+const fs = require('fs');
+
+const util = require('../../core/util.js');
+const config = util.getConfig();
+const dirs = util.dirs();
+
+const log = require(util.dirs().core + 'log');
+const postgresUtil = require('./util');
+
+const adapter = config.postgresql;
+
+// verify the correct dependencies are installed
+const pluginHelper = require(dirs.core + 'pluginUtil');
+const pluginMock = {
+  slug: 'postgresql adapter',
+  dependencies: config.postgresql.dependencies
+}
+
+const cannotLoad = pluginHelper.cannotLoad(pluginMock);
+if(cannotLoad) {
+  util.die(cannotLoad);
+}
+
+const pg = require('pg');
+
+const version = adapter.version;
+
+const dbName = postgresUtil.database();
+
+const mode = util.gekkoMode();
+
+const connectionString = config.postgresql.connectionString;
+
+const checkClient = new pg.Pool({
+  connectionString: connectionString + '/postgres',
+});
+const pool = new pg.Pool({
+  connectionString: connectionString + '/' + dbName,
+});
+
+// We need to check if the db exists first.
+// This requires connecting to the default
+// postgres database first. Your postgres
+// user will need appropriate rights.
+checkClient.connect((err, client, done) => {
+  if(err) {
+    util.die(err);
+  }
+
+  log.debug("Check database exists: " + dbName);
+  client.query("select count(*) from pg_catalog.pg_database where datname = $1", [dbName],
+    (err, res) => {
+      if(err) {
+        util.die(err);
+      }
+
+      if(res.rows[0].count !== '0') {
+        // database exists
+        log.debug("Database exists: " + dbName);
+        log.debug("Postgres connection pool is ready, db " + dbName);
+        upsertTables();
+        done();
+        return;
+      }
+
+      // database dot NOT exist
+
+      if(mode === 'backtest') {
+        // no point in trying to backtest with
+        // non existing data.
+        util.die(`History does not exist for exchange ${config.watch.exchange}.`);
+      }
+
+      createDatabase(client, done);
+    });
+});
+
+const createDatabase = (client, done) => {
+  client.query("CREATE DATABASE " + dbName, err => {
+    if(err) {
+      util.die(err);
+    }
+
+    log.debug("Postgres connection pool is ready, db " + dbName);
+    done();
+    upsertTables();
+  });
+}
+
+const upsertTables = () => {
+  const upsertQuery =
+    `CREATE TABLE IF NOT EXISTS
+    ${postgresUtil.table('candles')} (
+      id BIGSERIAL PRIMARY KEY,
+      start integer UNIQUE,
+      open double precision NOT NULL,
+      high double precision NOT NULL,
+      low double precision NOT NULL,
+      close double precision NOT NULL,
+      vwp double precision NOT NULL,
+      volume double precision NOT NULL,
+      trades INTEGER NOT NULL
+    );`;
+
+  pool.query(upsertQuery, (err) => {
+    if(err) {
+      util.die(err);
+    }
+  });
+}
+
+
+module.exports = pool;