Puppet Enterprise 2017.3

Use the classification endpoint takes a node name and a set of facts and returns information about how that node should be classified. The output can help you test your classification rules.

POST /v1/classified/nodes/<name>

Use the /v1/classified/nodes/\<name\> endpoint to retrieve the classification information for the node with the given name and facts as supplied in the body of the request.

Request format

The request body may contain a JSON object describing the facts and trusted facts of the node to be classified. The object may have these keys:

Key Definition
factThe regular, non-trusted facts of the node. The value of this key is a further object, whose keys are fact names, and whose values are the fact values. Fact values may be a string, number, boolean, array, or object.
trustedThe trusted facts of the node. The values of this key are subject to the same restrictions as those on the value of the fact key.

Response format

The response is a JSON object describing the node post-classification, using these keys:

Key Definition
name The name of the node (a string).
groups An array of the node groups (UUID strings) that this node was classified into.
environment The name of the environment that this node will use, which is taken from the node groups the node was classified into.
classes An object where the keys are class names and the values are objects that map parameter names to values.
parameters An object where the keys are top-level variable names and the values are the values that will be assigned to those variables.

This is an example of a response from this endpoint:

{
  "name": "foo.example.com",
  "groups": ["00000000-0000-4000-8000-000000000000", "08c7915b-b83f-4d11-9522-6a60e2378cef"],
  "environment": "staging",
  "parameters": {},
  "classes": {
    "apache": {
      "keepalive_timeout": 30,
      "log_level": "notice"
    }
  }
}

Error responses

If the node is classified into multiple node groups that define conflicting classifications for the node, the service returns a 500 Server Error response.

The body of this response contains the usual JSON error object described in the errors documentation.

The kind key of the error is "classification-conflict", the msg describes generally why this happens, and the details key contains an object that describes the specific conflicts encountered.

The details object may have these keys:

Key Definition
environment Maps directly to an array of value detail objects (described below).
variables Contains an object with a key for each conflicting variable, whose values are an array of value detail objects.
classes Contains an object with a key for each class that had conflicting parameter definitions, whose values are further objects that describe the conflicts for that class's parameters.

A value details object describes one of the conflicting values defined for the environment, a variable, or a class parameter. Each object contains these keys:

Key Definition
value The defined value, which will be a string for environment and class parameters, but for a variable may be any JSON value.
from The node group that the node was classified into that caused this value to be added to the node's classification. This group may not define the value, because it may be inherited from an ancestor of this group.
defined_by The node group that actually defined this value. This is often the from group, but could instead be an ancestor of that group.

This example shows a classification conflict error object with node groups truncated for clarity:

{
  "kind": "classification-conflict",
  "msg": "The node was classified into multiple unrelated node groups that defined conflicting class parameters or top-level variables. See `details` for a list of the specific conflicts.",
  "details": {
    "classes": {
      "songColors": {
        "blue": [
          {
            "value": "Blue Suede Shoes",
            "from": {
              "name": "Elvis Presley",
              "classes": {},
              "rule": ["=", "nodename", "the-node"],
              ...
            },
            "defined_by": {
              "name": "Carl Perkins",
              "classes": {"songColors": {"blue": "Blue Suede Shoes"}},
              "rule": ["not", ["=", "nodename", "the-node"]],
              ...
            }
          },
          {
            "value": "Since You've Been Gone",
            "from": {
              "name": "Aretha Franklin",
              "classes": {"songColors": {"blue": "Since You've Been Gone"}},
              ...
            },
            "defined_by": {
              "name": "Aretha Franklin",
              "classes": {"songColors": {"blue": "Since You've Been Gone"}},
              ...
            }
          }
        ]
      }
    }
  }
}

In this example, the conflicting "Blue Suede Shoes" value was included in the classification because the node matched the "Elvis Presley" node group (since that is the value of the "from" key), but that node group doesn't define the "Blue Suede Shoes" value. That value is defined by the "Carl Perkins" node group, which is an ancestor of the "Elvis Presley" node group, causing the latter to inherit the value from the former. The other conflicting value, "Since You've Been Gone", is defined by the same node group that the node matched.

POST /v1/classified/nodes/<name>/explanation

Use the /v1/classified/nodes/\<name\>/explanation endpoint to retrieve an explanation of how a node is classified by submitting its facts.

Request format

The body of the request must be a JSON object describing the node's facts. This object uses these keys:

Key Definition
fact Describes the regular (non-trusted) facts of the node. Its value must be a further object whose keys are fact names, and whose values are the corresponding fact values. Structured facts may be included here; structured fact values are further objects or arrays.
trusted Optional key that describes the trusted facts of the node. Its value has exactly the same format as the fact key's value.
name The node's name from the request's URL is merged into this object under this key.

This is an example of a valid request body:

{
  "fact": {
    "ear-tips": "pointed",
    "eyebrow pitch": "40",
    "hair": "dark",
    "resting bpm": "120",
    "blood oxygen transporter": "hemocyanin",
    "anterior tricuspids": "2",
    "appendices": "1",
    "spunk": "10"
  }
}

Response format

The response is a JSON object that describes how the node would be classified.

  • If the node would be successfully classified, this object contains the final classification.
  • If the classification would fail due to conflicts, this object contains a description of the conflicts.

This response is intended to provide insight into the entire classification process, so that if a node isn't classified as expected, you can trace the deviation.

Classification proceeds in this order:

  1. All node group rules are tested on the node's facts and name, and groups that don't match the node are culled, leaving the matching groups.
  2. Inheritance relations are used to further cull the matching groups, by removing any matching node group that has a descendant that is also a matching node group. Those node groups that are left over are leaf groups.
  3. Each leaf group is transformed into its inherited classification by adding all the inherited values from its ancestors.
  4. All of the inherited classifications and individual node classifications are inspected for conflicts. A conflict occurs whenever two inherited classifications define different values for the environment, a class parameter, or a top-level variable.
  5. Any individual node classification, including classes, class parameters, configuration data, and variables, is added.

  6. Individual node classification is applied to the group classification, forming the final classification, which is then returned to the client.

The JSON object returned by this endpoint uses these keys:

Key Definition
match_explanations Corresponds to step 1 of classification, finding the matching node groups. This key's value is an explanation object just like those found in node check-ins, which maps between a matching group's ID and an explained condition object that demonstrates why the node matched that group's rule.
leaf_groupsCorresponds to step 2 of classification, finding the leaves. This key's value is an array of the leaf groups (i.e., those groups that are not related to any of the other matching groups).
inherited_classificationsCorresponds to step 3 of classification, adding inherited values. This key's value is an object mapping from a leaf group's ID to the classification values provided by that group (after inheritance).
conflicts Corresponds to step 4 of classification. This key is present only if there are conflicts between the inherited classifications. Its value will be similar to a classification object, but wherever there was a conflict there will be an array of conflict details instead of a single classification value. Each of these details is an object with three keys: value, from, and defined_by. The value key is a conflicting value, the from key is the group whose inherited classification provided this value, and the defined_by key is the group that actually defined the value (which may be an ancestor of the from group).
individual_classificationCorresponds to step 5 of classification. Its value includes classes, class parameters, configuration data, and variables applied directly during this stage.
final_classification Corresponds to step 6 of classification, will only be present if there are no conflicts between the inherited classifications. Its value will be the result of merging all individual node classification and group classification.
node_as_received The submitted node object as received by the service, after adding the name and, if not supplied by the client, an empty trusted object. This key does not correspond to any of the classification steps.
classification_sourceAn annotated version of the classification that has the environment and every class parameter and variable replaced with an "annotated value" object. This key does not correspond to any of the classification steps.

This example shows a response the endpoint could return in the case of a successful classification:

{
  "node_as_received": {
    "name": "Tuvok",
    "trusted": {},
    "fact": {
      "ear-tips": "pointed",
      "eyebrow pitch": "30",
      "blood oxygen transporter": "hemocyanin",
      "anterior tricuspids": "2",
      "hair": "dark",
      "resting bpm": "200",
      "appendices": "0",
      "spunk": "0"
    }
  },
  "match_explanations": {
    "00000000-0000-4000-8000-000000000000": {
      "value": true,
      "form": ["~", {"path": "name", "value": "Tuvok"}, ".*"]
    },
    "8aeeb640-8dca-4b99-9c40-3b75de6579c2": {
      "value": true,
      "form": ["and",
               {
                 "value": true,
                 "form": [">=", {"path": ["fact", "eyebrow pitch"], "value": "30"}, "25"]
               },
               {
                 "value": true,
                 "form": ["=", {"path": ["fact", "ear-tips"], "value": "pointed"}, "pointed"]
               },
               {
                 "value": true,
                 "form": ["=", {"path": ["fact", "hair"], "value": "dark"}, "dark"]
               },
               {
                 "value": true,
                 "form": [">=", {"path": ["fact", "resting bpm"], "value": "200"}, "100"]
               },
               {
                 "value": true,
                 "form": ["=",
                          {
                            "path": ["fact", "blood oxygen transporter"],
                            "value": "hemocyanin"
                          },
                          "hemocyanin"
                 ]
               }
      ]
    }
  },
  "leaf_groups": {
    "8aeeb640-8dca-4b99-9c40-3b75de6579c2": {
      "name": "Vulcans",
      "id": "8aeeb640-8dca-4b99-9c40-3b75de6579c2",
      "parent": "00000000-0000-4000-8000-000000000000",
      "rule": ["and", [">=", ["fact", "eyebrow pitch"], "25"],
                      ["=", ["fact", "ear-tips"], "pointed"],
                      ["=", ["fact", "hair"], "dark"],
                      [">=", ["fact", "resting bpm"], "100"],
                      ["=", ["fact", "blood oxygen transporter"], "hemocyanin"]
      ],
      "environment": "alpha-quadrant",
      "variables": {},
      "classes": {
        "emotion": {"importance": "ignored"},
        "logic": {"importance": "primary"}
      },
      "config_data": {
        "USS::Voyager": {"designation": "subsequent"}
      }
    }
  },
  "inherited_classifications": {
    "8aeeb640-8dca-4b99-9c40-3b75de6579c2": {
      "environment": "alpha-quadrant",
      "variables": {},
      "classes": {
        "logic": {"importance": "primary"},
        "emotion": {"importance": "ignored"}
      },
      "config_data": {
        "USS::Enterprise": {"designation": "original"},
        "USS::Voyager": {"designation": "subsequent"}
      }
    }
  },
  "individual_classification": {
    "classes": {
      "emotion": {
        "importance": "secondary"
      }
    },
    "variables": {
      "full_name": "S'chn T'gai Spock"
    }
  },
  "final_classification": {
    "environment": "alpha-quadrant",
    "variables": {
      "full_name": "S'chn T'gai Spock"
    },
    "classes": {
      "logic": {"importance": "primary"},
      "emotion": {"importance": "secondary"}
    },
    "config_data": {
      "USS::Enterprise": {"designation": "original"},
      "USS::Voyager": {"designation": "subsequent"}
    }
  },
  "classification_sources": {
    "environment": {
      "value": "alpha-quadrant",
      "sources": ["8aeeb640-8dca-4b99-9c40-3b75de6579c2"]
    },
    "variables": {},
    "classes": {
      "emotion": {
        "puppetlabs.classifier/sources": ["8aeeb640-8dca-4b99-9c40-3b75de6579c2"],
        "importance": {
          "value": "secondary",
          "sources": ["node"]
        }
      },
      "logic": {
        "puppetlabs.classifier/sources": ["8aeeb640-8dca-4b99-9c40-3b75de6579c2"],
        "importance": {
          "value": "primary",
          "sources": ["8aeeb640-8dca-4b99-9c40-3b75de6579c2"]
        }
      },
      "config_data": {
        "USS::Enterprise": {
          "designation": {
            "value": "original",
            "sources": ["00000000-0000-4000-8000-000000000000"]
          }
        },
        "USS::Voyager": {
          "designation": {
            "value": "subsequent",
            "sources": ["8aeeb640-8dca-4b99-9c40-3b75de6579c2"]
          }
        }
      }
    }
  }
}

This example shows a response that resulted from conflicts:

{
  "node_as_received": {
    "name": "Spock",
    "trusted": {},
    "fact": {
      "ear-tips": "pointed",
      "eyebrow pitch": "40",
      "blood oxygen transporter": "hemocyanin",
      "anterior tricuspids": "2",
      "hair": "dark",
      "resting bpm": "120",
      "appendices": "1",
      "spunk": "10"
    }
  },
  "match_explanations": {
    "00000000-0000-4000-8000-000000000000": {
      "value": true,
      "form": ["~", {"path": "name", "value": "Spock"}, ".*"]
    },
    "a130f715-c929-448b-82cd-fe21d3f83b58": {
      "value": true,
      "form": [">=", {"path": ["fact", "spunk"], "value": "10"}, "5"]
    },
    "8aeeb640-8dca-4b99-9c40-3b75de6579c2": {
      "value": true,
      "form": ["and",
               {
                 "value": true,
                 "form": [">=", {"path": ["fact", "eyebrow pitch"], "value": "30"}, "25"]
               },
               {
                 "value": true,
                 "form": ["=", {"path": ["fact", "ear-tips"], "value": "pointed"}, "pointed"]
               },
               {
                 "value": true,
                 "form": ["=", {"path": ["fact", "hair"], "value": "dark"}, "dark"]
               },
               {
                 "value": true,
                 "form": [">=", {"path": ["fact", "resting bpm"], "value": "200"}, "100"]
               },
               {
                 "value": true,
                 "form": ["=",
                          {
                            "path": ["fact", "blood oxygen transporter"],
                            "value": "hemocyanin"
                          },
                          "hemocyanin"
                 ]
               }
      ]
    }
  },
  "leaf_groups": {
                   "a130f715-c929-448b-82cd-fe21d3f83b58": {
                     "name": "Humans",
                     "id": "a130f715-c929-448b-82cd-fe21d3f83b58",
                     "parent": "00000000-0000-4000-8000-000000000000",
                     "rule": [">=", ["fact", "spunk"], "5"],
                     "environment": "alpha-quadrant",
                     "variables": {},
                     "classes": {
                       "emotion": {"importance": "primary"},
                       "logic": {"importance": "secondary"}
                     }
                   },
                   "8aeeb640-8dca-4b99-9c40-3b75de6579c2": {
                     "name": "Vulcans",
                     "id": "8aeeb640-8dca-4b99-9c40-3b75de6579c2",
                     "parent": "00000000-0000-4000-8000-000000000000",
                     "rule": ["and", [">=", ["fact", "eyebrow pitch"], "25"],
                                     ["=", ["fact", "ear-tips"], "pointed"],
                                     ["=", ["fact", "hair"], "dark"],
                                     [">=", ["fact", "resting bpm"], "100"],
                                     ["=", ["fact", "blood oxygen transporter"], "hemocyanin"]
                     ],
                     "environment": "alpha-quadrant",
                     "variables": {},
                     "classes": {
                       "emotion": {"importance": "ignored"},
                       "logic": {"importance": "primary"}
                     }
                   }
  },
  "inherited_classifications": {
    "a130f715-c929-448b-82cd-fe21d3f83b58": {
      "environment": "alpha-quadrant",
      "variables": {},
      "classes": {
        "logic": {"importance": "secondary"},
        "emotion": {"importance": "primary"}
      }
    },
    "8aeeb640-8dca-4b99-9c40-3b75de6579c2": {
      "environment": "alpha-quadrant",
      "variables": {},
      "classes": {
        "logic": {"importance": "primary"},
        "emotion": {"importance": "ignored"}
      }
    }
  },
  "conflicts": {
    "classes": {
      "logic": {
        "importance": [
                        {
                          "value": "secondary",
                          "from": {
                            "name": "Humans",
                            "id": "a130f715-c929-448b-82cd-fe21d3f83b58",
                            ...
                          },
                          "defined_by": {
                            "name": "Humans",
                            "id": "a130f715-c929-448b-82cd-fe21d3f83b58",
                            ...
                          }
                        },
                        {
                          "value": "primary",
                          "from": {
                            "name": "Vulcans",
                            "id": "8aeeb640-8dca-4b99-9c40-3b75de6579c2",
                            ...
                          },
                          "defined_by": {
                            "name": "Vulcans",
                            "id": "8aeeb640-8dca-4b99-9c40-3b75de6579c2",
                            ...
                          }
                        }
        ]
      },
      "emotion": {
        "importance": [
                        {
                          "value": "ignored",
                          "from": {
                            "name": "Vulcans",
                            "id": "8aeeb640-8dca-4b99-9c40-3b75de6579c2",
                            ...
                          },
                          "defined_by": {
                            "name": "Vulcans",
                            "id": "8aeeb640-8dca-4b99-9c40-3b75de6579c2",
                            ...
                          }
                        },
                        {
                          "value": "primary",
                          "from": {
                            "name": "Humans",
                            "id": "a130f715-c929-448b-82cd-fe21d3f83b58",
                            ...
                          },
                          "defined_by": {
                            "name": "Humans",
                            "id": "a130f715-c929-448b-82cd-fe21d3f83b58",
                            ...
                          }
                        }
        ]
      }
    }
  },
  "individual_classification": {
    "classes": {
      "emotion": {
        "importance": "secondary"
      }
    },
    "variables": {
      "full_name": "S'chn T'gai Spock"
    }
  }
}
Back to top