Update README.md to add information on static export.

README.md

@@ -7,34 +7,73 @@ Tempest executions.
 Installation
 ------------
 Installation of the frontend requires Node.js and Bower. On Ubuntu:
-
 ```bash
 sudo apt-get install nodejs npm
 sudo npm install -g bower
 ```
 
 Then, install the Bower components by running, from the project directory,
-
 ```bash
 bower install
 ```
 
-Usage
+Usage - Server
------
+--------------
 First, install the necessary dependencies with Pip:
-
 ```bash
 sudo pip install -r requirements.txt
 ```
 
 The Django development server may then be used to view the interface. Run:
-
 ```bash
 python manage.py runserver
 ```
 
 You can then browse to the printed URL in your browser of choice.
 
+Usage - Static Site
+-------------------
+The server can be "snapshotted" and exported to a static HTML site using the
+`export_static.py` utility. StackViz can then be viewed using any web browser
+with no requirement of any server-side processing.
+
+To generate, run:
+```bash
+python export_static.py dest_dir
+```
+
+... where `dest_dir` is the path to a target directory where files should be
+written. When finished, the `index.html` file can be opened in a browser.
+
+Note that some browsers enforce content origin policies that may disallow
+XHRs when viewed directly from the local filesystem. To work around this, you
+can use something like the Python `SimpleHTTPServer`:
+```bash
+python -m SimpleHTTPServer
+```
+
+### GZipped Data
+As the log data can become quite large, exported files can be compressed with
+GZip to significantly reduce the size of the data files. To enable, run:
+```bash
+python export_static.py --gzip dest_dir
+```
+
+Data files will then be written in compressed form, and will be suffixed with
+`*.json.gz`. Note that web servers must be properly configured to serve
+pre-compressed files. Notably, Python's `SimpleHTTPServer` will not do this by
+default. However, [Twisted](https://twistedmatrix.com/trac/) can be used as a
+drop-in replacement as follows:
+```bash
+twistd -no web --path=.
+```
+
+Other web servers, such as Apache, should also serve these files correctly
+without any extra configuration.
+
+(Specifically, the response must have headers `Content-Type: application/json`
+and `Content-Encoding: gzip`.)
+
 Log Locations
 -------------
 Log locations are configured along with normal Django settings in