This library makes it possible to introspect dataset and aggregate nodes when it is instructed.


The following examples with be expressed in YAML for convenience's sake:

  • !aggr-scalar will refer to Scalar python function
  • !aggr-map will refer to Map python object
  • !aggr-seq will refer for Sequence python object

How to instructs merging

This yaml document has duplicate keys:

foo: !aggr-scalar first
foo: !aggr-scalar second
bar: !aggr-map {first: foo}
bar: !aggr-map {second: bar}
baz: !aggr-scalar 42

but tagged values instruct Salt that overlapping values they can be merged together:

foo: !aggr-seq [first, second]
bar: !aggr-map {first: foo, second: bar}
baz: !aggr-seq [42]

Default merge strategy is keep untouched

For example, this yaml document still has duplicate keys, but does not instruct aggregation:

foo: first
foo: second
bar: {first: foo}
bar: {second: bar}
baz: 42

So the late found values prevail:

foo: second
bar: {second: bar}
baz: 42


Aggregation is permitted between tagged objects that share the same type. If not, the default merge strategy prevails.

For example, these examples:

foo: {first: value}
foo: !aggr-map {second: value}

bar: !aggr-map {first: value}
bar: 42

baz: !aggr-seq [42]
baz: [fail]

qux: 42
qux: !aggr-scalar fail

are interpreted like this:

foo: !aggr-map{second: value}

bar: 42

baz: [fail]

qux: !aggr-seq [fail]


TODO: write this part

salt.utils.aggregation.aggregate(obj_a, obj_b, level=False, map_class=<class 'salt.utils.aggregation.Map'>, sequence_class=<class 'salt.utils.aggregation.Sequence'>)

Merge obj_b into obj_a.

>>> aggregate('first', 'second', True) == ['first', 'second']
class salt.utils.aggregation.Aggregate

Aggregation base.

class salt.utils.aggregation.Map(*args, **kwds)

Map aggregation.


Shortcut for Sequence creation

>>> Scalar('foo') == Sequence(['foo'])
class salt.utils.aggregation.Sequence

Sequence aggregation.