Restructure documentation

Signed-off-by: Roberto Rosario <roberto.rosario@mayan-edms.com>

docs/chapters/workflows.txt

@@ -0,0 +1,113 @@
+=========
+Workflows
+=========
+
+Introduction
+============
+
+Workflows provide a structured method for storing a sequence of states over
+which the a document will progress. Workflows keep track how a document has
+been processed so far.
+
+Workflows work by storing a series of states to help you know the "status"
+of a document. To move a workflow from one state to another, transitions are
+used.
+
+Transitions connect two different states and help provide context to know
+which state is possible to transition to, from a previous state. Transitions
+provide and order for the sequence of possible states changes.
+
+Transitions can be executed manually by users if they have the required access
+level as configure by the system administrator.
+
+.. blockdiag::
+   :caption: Example workflow. Circles represent states, rectangles represent transitions.
+
+      span_width = 30;
+
+      submitted [shape = circle, width = 60, height = 60];
+      approved [shape = circle, width = 60, height = 60];
+      rejected [shape = circle, width = 60, height = 60];
+      archived [shape = circle, width = 60, height = 60];
+
+      approve [label = approve];
+      reject [label = reject];
+      reopen [label = "re-open"];
+
+
+      submitted -> approve -> approved;
+      approved -> archived;
+      submitted -> reject -> rejected;
+      rejected -> archived;
+      archived -> reopen -> submitted;
+
+
+
+Workflows in Mayan EDMS are implemented as finite state machines
+(https://en.wikipedia.org/wiki/Finite-state_machine).
+
+Workflows are mainly used to represent business processes. But they can also be
+used an automation system to customized Mayan EDMS and have it perform some
+tasks automatically.
+
+
+Automation
+==========
+
+Besides being able to be executed manually by users, transitions can also be
+programmed execute automatically based on system events. This is called in
+Mayan EDMS transition triggering and is one of the tools available to
+automate business processes.
+
+For example:
+
+* Move a document from a "scanned" state to a "billed" state
+  when a tag is attached to the document.
+* Move a document from a "uploaded" state to a "OCR ready" state
+  when the OCR engine finishes processing the document.
+
+The other tool provided for process automation is being able to execute an
+action when a workflow state is reached or leaved. These are called state
+events.
+
+Some examples of state actions currently provided are:
+
+* Attach a tag to a document
+* Remove a tag from a document
+* Do an HTTP POST request to an external IP address
+* Edit the label or the description of a document.
+
+Other time more state actions are being added. Some state actions like the one
+that creates an HTTP POST request allow Mayan EDMS to trigger processes in
+external systems based on the state of a document. One example of this is
+triggering the billing process of an accounting system when an invoice is
+scanned in Mayan EDMS.
+
+Workflow state actions and transitions triggers are new features and are still
+evolving.
+
+Workflows allow translating business logic into a series of states. With the
+addition of state actions and transition triggers, the workflows in Mayan EDMS
+are no longer just informative but can be part of your actual business
+automation process.
+
+
+Implementation
+==============
+
+Internally, workflows are implemented as a finite state machines
+(https://en.wikipedia.org/wiki/Finite-state_machine). To make them simpler to
+use, workflow have been designed so that only one state can be the current
+active state for a workflow being executed. Another design decision is that
+every workflow needs at least one state marked as the initial state.
+
+
+Visualizations
+==============
+
+The graphical representation of a workflow is similar to a flowchart. The
+states are represented with circles. The transitions are represented with
+arrows. Circle with a double border represent the initial state of the workflow.
+
+To view the graphical representations of workflow use **Preview** button of
+the workflow in the setup view.