documentation for using guard in the PDP

Added guardpdp.rst and minor updates to other documentation.
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Change-Id: If0d430cdff3b9b1700b773b78c3d951698609714
Issue-Id: POLICY-335
Signed-off-by: Saryu Shah <ss3917@att.com>
diff --git a/docs/platform/guardpdp.rst b/docs/platform/guardpdp.rst
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+
+.. This work is licensed under a Creative Commons Attribution 4.0 International License.
+.. http://creativecommons.org/licenses/by/4.0
+
+************************
+Using guard in the PDP-D 
+************************
+
+.. contents::
+    :depth: 3
+
+This guide will help configure and test guard connection from PDP-D to PDP-X. This guide assumes that the PDP-D is installed and running policy properly with other properties being set properly.
+
+Configuration
+^^^^^^^^^^^^^ 
+
+Prerequisites
+-------------
+
+Stop Policy, open, and verify the config:
+
+- Stop policy with *policy stop*
+- Open *$POLICY_HOME/config/controlloop.properties.environment*
+- Make sure the *sql.db.host*, *sql.db.username* and *sql.db.password* are set correctly
+
+
+Guard Properties
+----------------
+
+**guard.url** - URL endpoint of the PDP-X which will receive the request.
+    - For example, *http://pdp:8081/pdp/api/getDecision* will connect to the localhost PDP-X.
+    - This request requires some configuration for PDP-X properties below.
+    - For testing this URL before running policy, see Verification below.
+
+**guard.jdbc.url** - URL of the database location to which the operations history will be written.
+    - For example, *mariadb://mariadb:3306/onap_sdk*.
+    - Note that the port is included.
+    - Note that at the end, the database name is used.
+
+**guard.disabled** - For enabling / disabling guard functionality.
+    - For example, to enable set it to false.
+    - When this is set to true, the previous two properties will be ignored.
+    - If guard is enabled, then the following PDP-X properties must also be set.
+
+
+PDP-X Properties
+----------------
+
+For testing these properties before running policy, see Verification below.
+
+**pdpx.host** - URL of the PDP-X
+    - For example, pdp can be used when PDP-X is on localhost.
+
+**pdpx.username** - User to authenticate
+
+**pdpx.password** - User Password
+
+**pdpx.environment** - Environment making requests
+    - For example, TEST
+
+**pdpx.client.username** - Client to authenticate
+
+**pdpx.client.password** - Client password
+
+
+
+Verification
+^^^^^^^^^^^^ 
+
+It is recommended to test using CLI tools before running since changing bash command parameters are faster than restarting policy.
+
+Logs Verification
+-----------------
+Checking the logs is straight forward. Check the *$POLICY_HOME/logs/error.log* file for the word "*callRESTfulPDP*" for any exceptions thrown. If they are thrown then there was a problem with the connection.
+You can also check the *$POLICY_HOME/logs/network.log* file for the word "*Indeterminate*" which implies the connection failed or got a non 200 response code.
+
+CLI Verification
+----------------
+
+It can be helpful to test the PDP-X connection using bash commands to make sure that the PDP-X properties are correct and the guard.url property is correct before running policy.
+
+**Method 1: httpie - CLI, cURL-like tool for humans**
+    
+    Using the http command we can make a request directly to PDP-X from the command line. Use the following form:
+
+    .. code-block:: bash
+    
+        http
+         POST pdp:8081/pdp/api/getDecision
+         Authorization:<yourAuth> ClientAuth:<yourClientAuth>
+         Environment:<environment> Content-Type:application/json < guard_request.json
+    
+    | where:
+    |     *<yourAuth>*       is the string generated from user:pass converted to base64 encoding 
+    |                        (a conversion tool is available at https://www.base64encode.org/)
+    |     *<yourClientAuth>* is generated the same way but from the client user and pass.
+    |     *<environment>*    is the context of the request. For example: TEST
+    |     *pdp*              is the host of the PDP-X
+    
+
+    The guard_request.json should be in the form of the following:
+    
+    .. code-block:: json
+       :caption: guard_request.json
+    
+        {
+          "decisionAttributes": {
+                "actor": "APPC",
+                "recipe": "Restart",
+                "target": "test13",
+                "clname" : "piptest"
+            },
+          "onapName": "PDPD"
+        }
+
+    * This request uses Basic Access Authentication.  
+    * This request will need further configuration if you are using a proxy.
+
+    
+    You know a successful connection is set when a response containing a “PERMIT” or “DENY” in uppercase is returned as follows:
+    
+    .. code-block:: json
+       :caption: Response
+    
+        {
+          "decision": "PERMIT",
+          "details": "Decision Permit. OK!"
+        }
+
+**Method 2: curl**
+
+    This method does the same as the http command but uses the alternate command of curl. The command should have the following form:
+
+    .. code-block:: bash 
+    
+        curl -u <user>:<pass> -H "Content-Type: application/json" -H "ClientAuth:<yourClientAuth>" 
+             -H "Environment:<environment>" -X POST -d @guard_req.json pdp:8081/pdp/api/getDecision
+
+    * Note that <user> and <pass> are in plain text, while the other headers follow the same form as in Method 1 above.
+    * This request will need further configuration if you are using a proxy
+    * The response is the same as in Method 1.
+
+
+**Note on Proxies**
+
+    * JVM system properties should be set if a proxy is being used to make the connection work with policy.
+    * The connection may succeed but have response code 401 or 403 with improper proxy authentication, which leads to "Indeterminate"
+    * Additionally, the CLI tools have specific proxy configuration. See their respective manual pages for more info.
+
+
+End of Document
+
+.. SSNote: Wiki page ref.  https://wiki.onap.org/display/DW/Using+guard+in+the+PDP-D