Update README.md

Author: nicpottier

README.md

@@ -2,7 +2,14 @@
 
 Simple service for indexing RapidPro contacts into ElasticSearch.
 
-This service can run in two modes:
+# Deploying
+
+As Indexer is a go application, it compiles to a binary and that binary along with the config file is all
+you need to run it on your server. You can find bundles for each platform in the
+[releases directory](https://github.com/nyaruka/rp-indexer/releases). You should only run a single indexer
+instance for a deployment.
+
+Indexer can run in two modes:
 
 1) the default mode, which simply queries the ElasticSearch database, finds the most recently
 modified contact, then on a schedule queries the `contacts_contact` table on the RapidPro
@@ -14,44 +21,90 @@ all contacts on RapidPro. Once complete, this switches out the alias for the con
 with the newly build index. This can be run on a cron (in parallel with the mode above) to rebuild
 your index occasionally to get rid of bloat.
 
-## Usage
+# Configuration
+
+Indexer uses a tiered configuration system, each option takes precendence over the ones above it:
+ 1. The configuration file
+ 2. Environment variables starting with `INDEXER_` 
+ 3. Command line parameters
+
+We recommend running Indexer with no changes to the configuration and no parameters, using only
+environment variables to configure it. You can use `% rp-indexer --help` to see a list of the
+environment variables and parameters and for more details on each option.
 
-It is recommended to run the service with two environment variables set:
+## RapidPro Configuration
+
+For use with RapidPro, you will want to configure these settings:
 
  * `INDEXER_DB`: a URL connection string for your RapidPro database
  * `INDEXER_ELASTIC_URL`: the URL for your ElasticSearch endpoint
+ 
+Recommended settings for error reporting:
+
+ * `INDEXER_SENTRY_DSN`: The DSN to use when logging errors to Sentry
+
+# Development
+
+Install Indexer source in your workspace with:
+
+```
+go get github.com/nyaruka/rp-indexer
+```
+
+Build Indexer with:
+
+```
+go build github.com/nyaruka/rp-indexer/cmd/rp-indexer
+```
+
+This will create a new executable in your current directory `rp-indexer`
+
+To run the tests you need to create the test database:
+
+```
+$ createdb elastic_test
+```
+
+To run all of the tests:
+
+```
+go test github.com/nyaruka/rp-indexer/... -p=1
+```
+
+# Usage
 
 ```
 Indexes RapidPro contacts to ElasticSearch
 
 Usage of indexer:
+  -cleanup
+    	whether to remove old indexes after a rebuild
   -db string
-        the connection string for our database (default "postgres://localhost/rapidpro")
+    	the connection string for our database (default "postgres://localhost/rapidpro?sslmode=disable")
   -debug-conf
-        print where config values are coming from
+    	print where config values are coming from
   -elastic-url string
-        the url for our elastic search instance (default "http://localhost:9200")
+    	the url for our elastic search instance (default "http://localhost:9200")
   -help
-        print usage information
+    	print usage information
   -index string
-        the alias for our contact index (default "contacts")
+    	the alias for our contact index (default "contacts")
+  -log-level string
+    	the log level, one of error, warn, info, debug (default "info")
   -poll int
-        the number of seconds to wait between checking for updated contacts (default 5)
+    	the number of seconds to wait between checking for updated contacts (default 5)
   -rebuild
-        whether to rebuild the index, swapping it when complete, then exiting (default false)
+    	whether to rebuild the index, swapping it when complete, then exiting (default false)
+  -sentry-dsn string
+    	the sentry configuration to log errors to, if any
 
 Environment variables:
+                             INDEXER_CLEANUP - bool
                                   INDEXER_DB - string
                          INDEXER_ELASTIC_URL - string
                                INDEXER_INDEX - string
+                           INDEXER_LOG_LEVEL - string
                                 INDEXER_POLL - int
                              INDEXER_REBUILD - bool
-```
-
-## Development
-
-To generate a local build for a linux amd64 architecture, use the following:
-
-```shell
-GOOS=linux GOARCH=amd64 go build github.com/nyaruka/rp-indexer/cmd/rp-indexer
-```
+                          INDEXER_SENTRY_DSN - string
+                          ```