Proposed Service Architecture for Kosmos

Change-Id: I68dc4521afe4efb520748fbc323867a045a2eb77

doc/source/conf.py

@@ -26,6 +26,7 @@ extensions = [
     #'sphinx.ext.intersphinx',
     'oslosphinx',
     'yasfb',
+    'sphinx.ext.graphviz'
 ]
 
 # Feed configuration for yasfb

specs/liberty/sysarch-diagram.dot

@@ -0,0 +1,108 @@
+digraph{
+
+    label="Kosmos System Overview";
+    overlap="ortho";
+    fontname="sans-serif"
+
+    subgraph cluster_api_service {
+        fontname="sans-serif"
+        label="API Service";
+        fontsize=12
+
+        WSGI[label="WSGI API", fontname="sans-serif", fontsize=10];
+    }
+
+    subgraph cluster_keystone {
+        fontname="sans-serif"
+        label="Keystone";
+        fontsize=12
+        style="dashed"
+
+        Keystone[label="Keystone API", fontname="sans-serif", fontsize=10, style="dotted"];
+    }
+
+    subgraph cluster_conductor_service {
+        fontname="sans-serif"
+        label="Conductor Service";
+        fontsize=12
+
+        Conductor[label="Conductor", fontname="sans-serif", fontsize=10];
+        Database[label="Database", fontname="sans-serif", fontsize=10, shape="folder"];
+    }
+
+    subgraph cluster_engine_service {
+        fontname="sans-serif"
+        label="Engine Service";
+        fontsize=12
+
+        node[shape=record];
+        Engine[label="<f0> Engine|<f1> GSLB Plugin Interface |<f2> Status Check Consumer", fontname="sans-serif", fontsize=10];
+        PluginDriver[label="GSLB Plugin Driver", fontname="sans-serif", fontsize=10, shape="component"]
+    }
+
+    subgraph cluster_gslb_appliance {
+        fontname="sans-serif"
+        fontsize=12
+        label="GSLB Appliance";
+        style="dashed"
+
+        Applicance[label="GSLB Traffic Director", fontname="sans-serif", fontsize=10, style="dotted"];
+        ApplicanceAPI[label="GSLB Appliance API", fontname="sans-serif", fontsize=10, style="dotted"];
+    }
+
+    subgraph cluster_status_checks {
+        fontname="sans-serif"
+        fontsize=12
+        label="Status Check Service";
+
+        Worker[label="Status Checking Worker", fontname="sans-serif", fontsize=10];
+
+        node[shape=record];
+        Checks[label="<f0> Build In Checks Interface |<f1> GSLB Plugin Checks Interface", fontname="sans-serif", fontsize=10];
+
+        BuiltInChecks[label="Built In Status Checks", fontname="sans-serif", fontsize=10]
+        PluginChecks[label="Plugin Status Checks", fontname="sans-serif", fontsize=10, shape="component"]
+    }
+
+    subgraph cluster_endpoints {
+        fontname="sans-serif"
+        fontsize=12
+        label="Endpoints";
+        style="dashed"
+
+        Endpoint1[label="Endpoint", fontname="sans-serif", fontsize=10, style="dotted"];
+        Endpoint2[label="Endpoint", fontname="sans-serif", fontsize=10, style="dotted"];
+        Endpoint3[label="Endpoint", fontname="sans-serif", fontsize=10, style="dotted"];
+
+    }
+
+
+    AdminUser[label="GSLB User", fontname="sans-serif", fontsize=10, style="dashed"];
+
+    AdminUser -> WSGI [dir="both"];
+
+    Keystone -> WSGI [dir="both"];
+
+    WSGI -> Conductor:f0 [dir="both"];
+
+    Conductor -> Database [dir="both"];
+
+    Engine:f0 -> Conductor [dir="both"];
+
+    Engine:f1 -> PluginDriver [dir="both"];
+    PluginDriver -> ApplicanceAPI [dir="both"];
+
+    Applicance -> ApplicanceAPI [dir="both"];
+
+    Worker -> Engine:f2;
+    Worker -> Checks [dir="both"];
+    Checks:f0 -> BuiltInChecks
+    Checks:f1 -> PluginChecks
+    BuiltInChecks -> {Endpoint1, Endpoint2, Endpoint3}
+    PluginChecks -> {Endpoint1, Endpoint2, Endpoint3}
+
+    EndUser[label="End User", fontname="sans-serif", fontsize=10, style="dashed"];
+
+    EndUser -> Applicance
+    Applicance -> {Endpoint1, Endpoint2, Endpoint3}
+}

specs/liberty/sysarch.rst

@@ -0,0 +1,78 @@
+..
+
+This work is licensed under a Creative Commons Attribution 3.0 Unported License.
+http://creativecommons.org/licenses/by/3.0/legalcode
+
+..
+  This template should be in ReSTructured text. The filename in the git
+  repository should match the launchpad URL, for example a URL of
+  https://blueprints.launchpad.net/kosmos/+spec/awesome-thing should be named
+  awesome-thing.rst .  Please do not delete any of the sections in this
+  template.  If you have nothing to say for a whole section, just write: None
+  For help with syntax, see http://sphinx-doc.org/rest.html
+  To test out your formatting, see http://www.tele3.cz/jbar/rest/rest.html
+
+=====================
+ System Architecture
+=====================
+
+Overview
+========
+
+Services
+--------
+
++-----------------------+--------------------------+---------------------------+-------+
+| service name          | deployment model         | purpose                   | notes |
++=======================+==========================+===========================+=======+
+| kosmos-api            | multiple                 | Configuration of GSLBs    |       |
++-----------------------+--------------------------+---------------------------+-------+
+| kosmos-conductor      | multiple - single region | Database Access           |       |
++-----------------------+--------------------------+---------------------------+-------+
+| kosmos-status-checker | multiple - global        | Check status of endpoints |       |
++-----------------------+--------------------------+---------------------------+-------+
+| kosmos-engine         | multiple - single region | Business Logic            |       |
++-----------------------+--------------------------+---------------------------+-------+
+
+kosmos-api
+^^^^^^^^^^
+
+The API would be a WSGI service that implements the API Spec previously approved.
+
+kosmos-conductor
+^^^^^^^^^^^^^^^^
+
+This will act as a single point of access to the DB, allowing for consistent data validation.
+
+kosmos-status-checker
+^^^^^^^^^^^^^^^^^^^^^
+
+This is a worker style service that will run recurring tasks - i.e. status checks on the defined endpoints
+
+This will have a plugin interface to allow for more checks to the loaded by different plugins, or for custom checks to be written by the deployer
+
+kosmos-engine
+^^^^^^^^^^^^^
+
+This is where all the business logic resides. This service will consume status results and decide if an endpoint should be removed / added.
+This service will then use the plugin loaded for the GSLB backend to orchestrate this.
+
+Diagram
+-------
+
+.. graphviz:: sysarch-diagram.dot
+
+Implementation
+==============
+
+Assignee(s)
+-----------
+
+Primary assignee:
+  kosmos-drivers
+
+Milestones
+----------
+
+Target Milestone for completion:
+  M-1