Add postgresGCP config and toggle to allow switching (#39)

config/test.json

@@ -9,5 +9,18 @@
     "database": "entity_test",
     "max": 10,
     "statement_timeout": 10000
+  },
+  "postgresGCP": {
+    "user": "et",
+    "password": "ET",
+    "host": "localhost",
+    "port": "5435",
+    "database": "entity_test",
+    "max": 10,
+    "statement_timeout": 10000,
+    "ssl": false
+  },
+  "toggle": {
+    "useGCPPostgres": false
   }
 }

lib/client.js

@@ -2,15 +2,22 @@
 
 const config = require("exp-config");
 const pg = require("pg");
+const toggle = require("./toggle");
+
+const {user, password, database, host, port, statementTimeout, ssl, max = 10} = toggle("useGCPPostgres")
+  ? config.postgresGCP
+  : config.postgres;
 
 const poolConfig = {
-  user: config.postgres.user,
-  password: config.postgres.password,
-  database: config.postgres.database,
-  host: config.postgres.host,
-  port: config.postgres.port,
-  max: config.postgres.max || 10,
-  statement_timeout: config.postgres.statement_timeout || 10000 // eslint-disable-line
+  user,
+  password,
+  database,
+  host,
+  port,
+  ssl,
+  max,
+  // eslint-disable-next-line camelcase
+  statement_timeout: statementTimeout || 10000
 };
 
 let pool;

lib/toggle.js

@@ -0,0 +1,23 @@
+"use strict";
+const config = require("exp-config");
+
+const knownToggles = ["useGCPPostgres"];
+
+knownToggles.sort();
+
+config.toggle = config.toggle || {};
+
+function toggle(name) {
+  if (knownToggles.indexOf(name) === -1) {
+    throw new Error(`Unknown toggle '${name}'`);
+  }
+  if (process.env.NODE_ENV === "test") {
+    return true;
+  }
+  const value = config.toggle[name];
+  return value === true || value === "true";
+}
+
+toggle.knownToggles = knownToggles;
+
+module.exports = toggle;