Add pre-req information to test/README.md

Author: cjbj

test/README.md

@@ -76,6 +76,27 @@ CREATE PROCEDURE, CREATE SEQUENCE, CREATE TRIGGER.
 export NODE_PATH=<some-directory>/node-oracledb/lib
 ```
 
+### 1.6 Available Environment Variables
+
+Setting the following environment variables will override the default values defined in test/dbconfig.js.
+
+* `NODE_ORACLEDB_USER` overrides the username of the schema user which you used for testing.
+
+* `NODE_ORACLEDB_PASSWORD` overrides the password of the schema user which you used for testing.
+
+* `NODE_ORACLEDB_CONNECTIONSTRING` overrides the connection string that points to your database's location.
+
+* `NODE_ORACLEDB_EXTERNALAUTH` overrides the options for external authentication tests. Setting this environment variable to "true" will enable the tests that require external authentication.
+
+* `NODE_ORACLEDB_DBA_PRIVILEGE` overrides the options for DBA privilege. Setting this environment variable to "true" will enable the tests and utilities that require DBA privilege.
+
+* `NODE_ORACLEDB_DBA_USER` overrides the username of the DBA user which you used for testing, disabled if `NODE_ORACLEDB_DBA_PRIVILEGE` is not `true`.
+
+* `NODE_ORACLEDB_DBA_PASSWORD` overrides the password of the DBA user which you used for testing, disabled if `NODE_ORACLEDB_DBA_PRIVILEGE` is not `true`.
+
+* `NODE_ORACLEDB_PROXY_SESSION_USER` provides the username of a schema user that can connect through the schema user which you used for testing using proxy authentication. Setting this environment variable will enable the tests that require proxy authentication.
+
+
 ## 2. Run tests
 
 ### 2.1 Run the complete test suite
@@ -94,7 +115,29 @@ cd node_oracledb
 
 See [mochajs.org](http://mochajs.org/) for more information on running tests with mocha.
 
-## 3. Add Tests
+## 3. Enable test(s) that requires extra configuration
+
+The following test(s) are automatically skipped if their required environment variable(s) are not properly set.
+
+### 3.1 externalProxyAuth.js
+This test aims to test the combined usage of external authentication and proxy authentication. To run this test, you need to complete the following prerequisite setups.
+
+* Enable external authentication on the schema user which you used for testing. See [Documentation for External Authentication](https://oracle.github.io/node-oracledb/doc/api.html#extauth) for more information on external authentication. Then use the following command to enable external authentication in the test suite.
+
+	```
+	export NODE_ORACLEDB_EXTERNALAUTH true
+
+	```
+
+* Enable proxy authentication on another schema user specified by environment variable `NODE_ORACLEDB_PROXY_SESSION_USER` that connects through the schema user which you used for testing. See [Documentation for Pool Proxy Authentication](https://oracle.github.io/node-oracledb/doc/api.html#pool-proxy-authentication) for more information on proxy authentication. Then use the following command to enable proxy authentication in the test suite.
+
+	```
+	export NODE_ORACLEDB_PROXY_SESSION_USER "Your_Proxy_Authenticating_User"
+
+	```
+
+
+## 4. Add Tests
 
 See [CONTRIBUTING](https://github.com/oracle/node-oracledb/blob/master/CONTRIBUTING.md)
 for general information on contribution requirements.
@@ -106,14 +149,14 @@ shows the numbering of tests.
 In order to include your tests in the suite, add each new test file
 name to [`test/opts/mocha.opts`](https://github.com/oracle/node-oracledb/blob/master/test/opts/mocha.opts).
 
-## 4. Troubleshooting
+## 5. Troubleshooting
 
 You may encounter some troubles when running the test suite. These troubles
 might be caused by the concurrency issue of Mocha framework, network latencies,
 or database server issues. This section gives some issues that we ever saw
 and our solutions.
 
-### 4.1 ORA-00054: resource busy and acquire with NOWAIT specified or timeout expired
+### 5.1 ORA-00054: resource busy and acquire with NOWAIT specified or timeout expired
 
 This error occurs when Node.js programs try to change database objects which
 hold locks. The workaround would be:
@@ -123,7 +166,7 @@ test files.
 (2) Try not to use 'beforeEach' blocks for object operations to avoid
 the interference between cases.
 
-### 4.2 ORA-00018: maximum number of sessions exceeded
+### 5.2 ORA-00018: maximum number of sessions exceeded
 
 This error occurs when the test suite takes up more sessions than the
 configured limit. You can alter the session limit on the database server side.
@@ -140,7 +183,7 @@ do
 done
 ```
 
-### 4.3 ORA-28865: SSL connection closed
+### 5.3 ORA-28865: SSL connection closed
 
 You may encounter this error when the test suite sends more connection
 requests per second than the database is configured to handle.