utahdave / changes

Show difference in changes dictionary in Salt.

Salt Vagrant Demo showing Salt State "changes" and "comments" field differences

A Salt Demo using Vagrant.

Instructions

Run the following commands in a terminal. Git, VirtualBox and Vagrant must already be installed.

git clone https://github.com/UtahDave/changes.git
cd changes
vagrant plugin install vagrant-vbguest
vagrant up

This will download an Ubuntu VirtualBox image and create two virtual machines for you. One will be a Salt Master named master and the other will be named minion1. The Salt Minion will point to the Salt Master and the Minion's keys will already be accepted. Because the keys are pre-generated and reside in the repo, please be sure to regenerate new keys if you use this for production purposes.

You can then run the following commands to log into the Salt Master and begin using Salt.

vagrant ssh master
sudo salt \* test.ping

You can see the difference between the output of a successful orchestration state and a failure with the following commands:

sudo salt-run state.orch changes.succeed --out json
sudo salt-run state.orch changes.fail --out json 2> /dev/null

You should see something like the following:

sudo salt minion1 pkg.remove nano
sudo salt-run state.orch changes.succeed --out json
{
    "outputter": "highstate",
    "data": {
        "saltmaster.local_master": {
            "salt_|-Step01_|-Step01_|-state": {
                "comment": "States ran successfully. Updating minion1.",
                "name": "Step01",
                "start_time": "01:47:59.026329",
                "result": true,
                "duration": 8006.557,
                "__run_num__": 0,
                "__jid__": "20171109014759087105",
                "__sls__": "changes.succeed",
                "changes": {
                    "ret": {
                        "minion1": {
                            "pkg_|-install_good_package_|-nano_|-installed": {
                                "comment": "The following packages were installed/updated: nano",
                                "name": "nano",
                                "start_time": "01:47:59.077133",
                                "result": true,
                                "duration": 7202.901,
                                "__run_num__": 0,
                                "__sls__": "changes.pkg_succeed",
                                "changes": {
                                    "nano": {
                                        "new": "2.5.3-2ubuntu2",
                                        "old": ""
                                    }
                                },
                                "__id__": "install_good_package"
                            }
                        }
                    },
                    "out": "highstate"
                },
                "__id__": "Step01"
            }
        }
    },
    "retcode": 0
}

And like this on failure:

sudo salt-run state.orch changes.fail --out json 2> /dev/null
{
    "outputter": "highstate",
    "data": {
        "saltmaster.local_master": {
            "salt_|-Step01_|-Step01_|-state": {
                "comment": "Run failed on minions: minion1\nFailures:\n    {\n        \"minion1\": {\n            \"pkg_|-install_fake_package_|-asdfasdf_|-installed\": {\n                \"comment\": \"Problem encountered installing package(s). Additional info follows:\\n\\nerrors:\\n    - Running scope as unit run-r9c32e46083d64e3785334798d98071e9.scope.\\n      E: Unable to locate package asdfasdf\", \n                \"name\": \"asdfasdf\", \n                \"start_time\": \"01:41:40.142147\", \n                \"result\": false, \n                \"duration\": 4373.974, \n                \"__run_num__\": 0, \n                \"__sls__\": \"changes.pkg_fail\", \n                \"changes\": {}, \n                \"__id__\": \"install_fake_package\"\n            }\n        }\n    }\n",
                "name": "Step01",
                "start_time": "01:41:40.036106",
                "result": false,
                "duration": 5130.725,
                "__run_num__": 0,
                "__jid__": "20171109014140096711",
                "__sls__": "changes.fail",
                "changes": {},
                "__id__": "Step01"
            }
        }
    },
    "retcode": 1
}

You can see from the above results that when there's a success the changes field is populated with a dictionary cleanly describing the changes that happened. But when there's a failure the info about the failure is added to the comments field as a string with spaces and hard returns. This makes it difficult to parse reliably when used programatically.