Rekey on member (#33836)

* Change cast_list_to_dict to more generic rekey_on_member

cast_list_to_dict was taking an arbitrary data format in and returning
an arbitrary data format out.  Rework this to be a more generic function
which creates a dict of dicts based on a member of the dict.

Remove cast_dict_to_list since rekey_on_member handles the use cases we
know about and cast_dict_to_list suffers from the same problems as
cast_list_to_dict.  If this is still needed we could think about filters
we could add to do this in a short jinja2 pipeline.

* Fix bare excepts (bare excepts even catch sys.exit())

lib/ansible/plugins/filter/cast_type.py

@@ -1,63 +0,0 @@
-# Author Ken Celenza <ken@networktocode.com>
-# Author Jason Edelman <jason@networktocode.com>
-
-# Make coding more python3-ish
-from __future__ import (absolute_import, division, print_function)
-__metaclass__ = type
-
-from ansible.errors import AnsibleError, AnsibleFilterError
-
-
-def cast_list_to_dict(data, key):
-    new_obj = {}
-
-    if not isinstance(data, list):
-        raise AnsibleFilterError("Type is not a valid list")
-    for item in data:
-        if not isinstance(item, dict):
-            raise AnsibleFilterError("List item is not a valid dict")
-        try:
-            key_elem = item.get(key)
-        except Exception as e:
-            raise AnsibleFilterError(str(e))
-        if new_obj.get(key_elem):
-            raise AnsibleFilterError("Key {0} is not unique, cannot correctly turn into dict".format(key_elem))
-        elif not key_elem:
-            raise AnsibleFilterError("Key {0} was not found".format(key))
-        else:
-            new_obj[key_elem] = item
-    return new_obj
-
-
-def cast_dict_to_list(data, key_name):
-    new_obj = []
-
-    if not isinstance(data, dict):
-        raise AnsibleFilterError("Type is not a valid dict")
-    for key, value in data.items():
-        if not isinstance(value, dict):
-            raise AnsibleFilterError("Type of key {0} value {1} is not a valid dict".format(key, value))
-        if value.get(key_name):
-            raise AnsibleFilterError("Key name {0} is already in use, cannot correctly turn into dict".format(key_name))
-        value[key_name] = key
-        new_obj.append(value)
-    return new_obj
-
-
-class FilterModule(object):
-    '''Convert a list to a dictionary provided a key that exists in all dicts.
-        If it does not, that dict is omitted
-    '''
-    def filters(self):
-        return {
-            'cast_list_to_dict': cast_list_to_dict,
-            'cast_dict_to_list': cast_dict_to_list,
-        }
-
-
-if __name__ == "__main__":
-    list_data = [{"proto": "eigrp", "state": "enabled"}, {"proto": "ospf", "state": "enabled"}]
-    print(cast_list_to_dict(list_data, 'proto'))
-
-    dict_data = {'eigrp': {'state': 'enabled', 'as': '1'}, 'ospf': {'state': 'enabled', 'as': '2'}}
-    print(cast_dict_to_list(dict_data, 'proto'))

lib/ansible/plugins/filter/mathstuff.py

@@ -1,4 +1,7 @@
-# (c) 2014, Brian Coca <bcoca@ansible.com>
+# Copyright 2014, Brian Coca <bcoca@ansible.com>
+# Copyright 2017, Ken Celenza <ken@networktocode.com>
+# Copyright 2017, Jason Edelman <jason@networktocode.com>
+# Copyright 2017, Ansible Project
 #
 # This file is part of Ansible
 #
@@ -26,7 +29,9 @@ import math
 
 from ansible import errors
 from ansible.module_utils import basic
+from ansible.module_utils.six import binary_type, text_type
 from ansible.module_utils.six.moves import zip, zip_longest
+from ansible.module_utils._text import to_native
 
 
 def unique(a):
@@ -113,7 +118,7 @@ def human_readable(size, isbits=False, unit=None):
     ''' Return a human readable string '''
     try:
         return basic.bytes_to_human(size, isbits, unit)
-    except:
+    except Exception:
         raise errors.AnsibleFilterError("human_readable() can't interpret following string: %s" % size)
 
 
@@ -121,10 +126,55 @@ def human_to_bytes(size, default_unit=None, isbits=False):
     ''' Return bytes count from a human readable string '''
     try:
         return basic.human_to_bytes(size, default_unit, isbits)
-    except:
+    except Exception:
         raise errors.AnsibleFilterError("human_to_bytes() can't interpret following string: %s" % size)
 
 
+def rekey_on_member(data, key, duplicates='error'):
+    """
+    Rekey a dict of dicts on another member
+
+    May also create a dict from a list of dicts.
+
+    duplicates can be one of ``error`` or ``overwrite`` to specify whether to error out if the key
+    value would be duplicated or to overwrite previous entries if that's the case.
+    """
+    if duplicates not in ('error', 'overwrite'):
+        raise errors.AnsibleFilterError("duplicates parameter to rekey_on_member has unknown value: {0}".format(duplicates))
+
+    new_obj = {}
+
+    if isinstance(data, collections.Mapping):
+        iterate_over = data.values()
+    elif isinstance(data, collections.Iterable) and not isinstance(data, (text_type, binary_type)):
+        iterate_over = data
+    else:
+        raise errors.AnsibleFilterError("Type is not a valid list, set, or dict")
+
+    for item in iterate_over:
+        if not isinstance(item, collections.Mapping):
+            raise errors.AnsibleFilterError("List item is not a valid dict")
+
+        try:
+            key_elem = item[key]
+        except KeyError:
+            raise errors.AnsibleFilterError("Key {0} was not found".format(key))
+        except Exception as e:
+            raise errors.AnsibleFilterError(to_native(e))
+
+        # Note: if new_obj[key_elem] exists it will always be a non-empty dict (it will at
+        # minimun contain {key: key_elem}
+        if new_obj.get(key_elem, None):
+            if duplicates == 'error':
+                raise errors.AnsibleFilterError("Key {0} is not unique, cannot correctly turn into dict".format(key_elem))
+            elif duplicates == 'overwrite':
+                new_obj[key_elem] = item
+        else:
+            new_obj[key_elem] = item
+
+    return new_obj
+
+
 class FilterModule(object):
     ''' Ansible math jinja2 filters '''
 
@@ -154,6 +204,7 @@ class FilterModule(object):
             # computer theory
             'human_readable': human_readable,
             'human_to_bytes': human_to_bytes,
+            'rekey_on_member': rekey_on_member,
 
             # zip
             'zip': zip,