feat: support custom AWS.Config instead of requiring individual parameters

resolves #133

Author: Kyle Smith

index.js

@@ -6,17 +6,19 @@ module.exports = Dyno;
 
 /**
  * Creates a dyno client. You must provide a table name and the region where the
- * table resides. Where applicable, dyno will use this table as the default in
- * your requests. However you can override this when constructing any individual
- * request.
+ * table resides. Region can be supplied with either the `region` option, or as
+ * a property on the `awsConfig` option. Where applicable, dyno will use this
+ * table as the default in your requests. However you can override this when
+ * constructing any individual request.
  *
  * If you do not explicitly pass credentials when creating a dyno client, the
  * aws-sdk will look for credentials in a variety of places. See [the configuration guide](http://docs.aws.amazon.com/AWSJavaScriptSDK/guide/node-configuring.html)
  * for details.
  *
  * @param {object} options - configuration parameters
  * @param {string} options.table - the name of the table to interact with by default
- * @param {string} options.region - the region in which the default table resides
+ * @param {object} [options.awsConfig] - an instance of AWS.Config to use in lieu of setting individual options. See [AWS.Config docs for details](http://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/Config.html)
+ * @param {string} [options.region] - the region in which the default table resides
  * @param {string} [options.endpoint] - the dynamodb endpoint url
  * @param {object} [options.httpOptions] - httpOptions to provide the aws-sdk client. See [constructor docs for details](http://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/DynamoDB.html#constructor-property).
  * @param {string} [options.accessKeyId] - credentials for the client to utilize
@@ -60,20 +62,25 @@ function Dyno(options) {
    */
 
   if (!options.table) throw new Error('table is required'); // Demand table be specified
-  if (!options.region) throw new Error('region is required');
 
   var config = {
-    region: options.region,
-    endpoint: options.endpoint,
-    params: { TableName: options.table }, // Sets `TableName` in every request
-    httpOptions: options.httpOptions || { timeout: 5000 }, // Default appears to be 2 min
-    accessKeyId: options.accessKeyId,
-    secretAccessKey: options.secretAccessKey,
-    sessionToken: options.sessionToken,
-    logger: options.logger,
-    maxRetries: options.maxRetries
+    params: {
+      TableName: options.table // Sets `TableName` in every request
+    },
+    httpOptions: {
+      timeout: 5000 // Default appears to be 2 min
+    }
   };
 
+  if (!options.awsConfig) {
+    if (!options.region) throw new Error('region is required');
+    Object.assign(config, options);
+  } else {
+    config = options.awsConfig;
+    config.params = config.params || {};
+    config.params.TableName = options.table;
+  }
+
   var client = new AWS.DynamoDB(config);
   var docClient = new AWS.DynamoDB.DocumentClient({ service: client });
   var tableFreeClient = new AWS.DynamoDB(_(config).omit('params')); // no TableName in batch requests

test/index.test.js

@@ -1,3 +1,4 @@
+var AWS = require('aws-sdk');
 var test = require('tape');
 var Dyno = require('..');
 
@@ -8,8 +9,11 @@ test('[index] invalid config', function(assert) {
 
   assert.throws(function() {
     Dyno({ table: 'my-table' });
-  }, /region is required/, 'rejects config without region');
+  }, /region is required/, 'rejects config without region when awsConfig not set');
 
+  assert.doesNotThrow(function() {
+    Dyno({ table: 'my-table', awsConfig: new AWS.Config() });
+  }, 'accepts config without region when awsConfig is set');
   assert.end();
 });
 
@@ -158,6 +162,13 @@ test('[index] configuration', function(assert) {
   assert.deepEqual(dyno.config.logger, config.logger, 'sets logger');
   assert.equal(dyno.config.maxRetries, config.maxRetries, 'sets maxRetries');
 
+  var awsConfig = new AWS.Config();
+  var awsDyno = Dyno({
+    awsConfig: awsConfig,
+    table: 'my-table'
+  });
+  assert.strictEqual(awsDyno.config, awsConfig, 'uses awsConfig');
+
   var multi = Dyno.multi(
     { table: 'read-table', region: 'us-east-1' },
     { table: 'write-table', region: 'us-east-1' }