Fixed #494 - Doc the type of errors

Signed-off-by: Chin Yeung Li <[email protected]>

Author: chinyeungli

docs/source/index.rst

@@ -11,3 +11,4 @@ Welcome to the AboutCode Toolkit's Documentation.
    General <general.rst>
    Specification <specification.rst>
    Reference <reference.rst>
+   Type of Errors <type_of_errors.rst>

docs/source/type_of_errors.rst

@@ -0,0 +1,93 @@
+.. _type_of_errors:
+
+==============
+Type of Errors 
+==============
+
+We have 6 type of errors as describe below:
+
+NOTSET
+======
+
+Trigger:
+--------
+
+    * None
+
+Details
+^^^^^^^
+
+    We do not have event to trigger this error.
+
+
+DEBUG
+=====
+
+Trigger:
+--------
+
+    * None
+
+Details
+^^^^^^^
+
+    We do not have event to trigger this error.
+
+
+INFO
+====
+
+Trigger:
+--------
+
+    * `about_resource` not found
+    * Custom fields detected
+    * Empty field value
+
+
+WARNING
+=======
+
+Trigger:
+--------
+
+    * Duplicated value being ignored
+    * Invalid Package URL from input
+    * Invalid URL from input
+
+
+ERROR
+=====
+
+Trigger:
+--------
+
+    * Invalid license
+    * Invalid API call
+    * Invalid character
+    * Invalid input
+    * Duplicated field name
+    * Incorrect input format
+    * Failure to write ABOUT file
+    * Network problem
+
+
+CRITICAL
+========
+
+Trigger:
+--------
+
+    * Invalid template
+    * File field not found
+    * Duplicated `about_resource`
+    * Not supported field format
+    * Essential or required field not found
+    * Internal error
+    * Empty ABOUT file
+    * Invalid ABOUT file
+
+
+.. note::
+   If `--verbose` is set, all the detected errors will be reported.
+   Otherwise, only "CRITICAL", "ERROR" and 'WARNING" will be reported.