Update README.md

Signed-off-by: Sangwan Kwon <sangwan.kwon@samsung.com>

diff --git a/README.md b/README.md
index 642b4c0..9113a09 100644 (file)
--- a/README.md
+++ b/README.md
@@ -4,17 +4,45 @@ ViST(Virtual Security Table) is a security monitoring framework using SQL query.
 - Views security resources as virtual tables and manipulates them through SQL queries.
 - Adopts a plug-in architecture and uses [osquery](https://osquery.io/) as the query analysis engine.
 
-# Architecture
-![tizen-osquery-architecture](https://github.sec.samsung.net/storage/user/692/files/74819c00-4c95-11e9-9648-54e02513e338)
+# Architecture (Layered View)
+![vist-architecture](https://github.sec.samsung.net/storage/user/692/files/82d63880-fa6c-11e9-91d2-af36faed1869)
 
-# Advantages of tizen-osquery better than osquery
-- More available
-  - We support not only monitor-feature("SELECT") but also control-feature("UPDATE") additionally.
-- More strict
-  - We can catch query errors at build time by query-builder.
-- More compact
-  - We focus the device security.
+# Programming Abstraction
+ViST provides three types of API.  
+One is for data structure and the other is for functional.
 
-# Branch info
-- master: osquery for tizen
-- upstream: full osquery code (facebook/osquery)
+## Schema API
+Schema API represents the data structure of Virtua Tables.  
+This is referred to by Client API and Admin API.
+
+## Client API (SELECT)
+Client API is a functioanl API for monitoring Virtual Tables.  
+Since Client API generates 'select query' by using query-builder, it doesn't need to write a query directly.
+
+```cpp
+  /// Querying device policies using Client API
+  vist::VirtualTable<Policy> table;
+  for (const auto& row : table) {
+    vist::schema::Policy policy = { row[&Policy::name], row[&Policy::value] };
+    std::cout << "Policy name: " << policy.name << ", ";
+    std::cout << "Policy value: " << policy.value << "\n";
+  }
+```
+
+## Admin API (SELECT, INSERT, UPDATE, DELETE)
+Admin API is a functioanl API for manipulating Virtual Tables.  
+This executes the query statement for the virtual table.
+```cpp
+   /// Registering policy admin using Admin API
+   vist::Query::Execute("INSERT INTO policy_admin (name, uid) VALUES ('admin', 0)");
+   
+   /// rows includes [name:admin, uid:0]
+   auto rows = vist::Query::Execute("SELECT * FROM policy_admin");
+   
+   /// Excluding policy admin using Admin API
+   vist::Query::Execute("DELETE FROM policy_admin WHERE name = 'testAdmin' AND uid = 1");
+```
+
+# Contacts
+- Sangwan Kwon (sangwan.kwon@samsung.com)
+- Jaemin Ryu (jm77.ryu@samsung.com)