5c27a249b7
This adds the first reversible resource (file) and the necessary engine API hooks to make it all work. This allows a special "reversed" resource to be added to the subsequent graph in the stream when an earlier version "disappears". This disappearance can happen if it was previously in an if statement that then becomes false. It might be wise to combine the use of this meta parameter with the use of the `realize` meta parameter to ensure that your reversed resource actually runs at least once, if there's a chance that it might be gone for a while. This patch also adds a new test harness for testing resources. It doesn't test the "live" aspect of resources, as it doesn't run Watch, but it was designed to ensure CheckApply works as intended, and it runs very quickly with a simplified timeline of happenings.
mgmt: next generation config management!
About:
Mgmt is a real-time automation tool. It is familiar to existing configuration
management software, but is drastically more powerful as it can allow you to
build real-time, closed-loop feedback systems, in a very safe way, and with a
surprisingly small amout of our mcl code. For example, the following code will
ensure that your file server is set to read-only when it's friday.
import "datetime"
$is_friday = datetime.weekday(datetime.now()) == "friday"
file "/srv/files/" {
state => "exists",
mode => if $is_friday { # this updates the mode, the instant it changes!
"0550"
} else {
"0770"
},
}
It can run continuously, intermittently, or on-demand, and in the first case, it will guarantee that your system is always in the desired state for that instant! In this mode it can run as a decentralized cluster of agents across your network, each exchanging information with the others in real-time, to respond to your changing needs. For example, if you want to ensure that some resource runs on a maximum of two hosts in your cluster, you can specify that as well:
import "sys"
import "world"
# we'll set a few scheduling options:
$opts = struct{strategy => "rr", max => 2, ttl => 10,}
# schedule in a particular namespace with options:
$set = world.schedule("xsched", $opts)
if sys.hostname() in $set {
# use your imagination to put something more complex right here...
print "i got scheduled" {} # this will run on the chosen machines
}
As you add and remove hosts from the cluster, the real-time schedule function
will dynamically pick up to two hosts from the available pool. These specific
functions aren't intrinsic to the core design, and new ones can be easily added.
Please read on if you'd like to learn more...
Community:
Come join us in the mgmt community!
| Medium | Link |
|---|---|
| IRC | #mgmtconfig on Freenode |
| @mgmtconfig & #mgmtconfig | |
| Mailing list | mgmtconfig-list@redhat.com |
| Patreon | purpleidea on Patreon |
| Liberapay | purpleidea on Liberapay |
Status:
Mgmt is a next generation automation tool. It has similarities to other tools in the configuration management space, but has a fast, modern, distributed systems approach. The project contains an engine and a language. Please have a look at an introductory video or blog post.
Mgmt is a fairly new project. It is usable today, but not yet feature complete. With your help you'll be able to influence our design and get us to 1.0 sooner! Interested users should read the quick start guide.
Documentation:
Please read, enjoy and help improve our documentation!
| Documentation | Additional Notes |
|---|---|
| quick start guide | for everyone |
| frequently asked questions | for everyone |
| general documentation | for everyone |
| language guide | for everyone |
| function guide | for mgmt developers |
| resource guide | for mgmt developers |
| style guide | for mgmt developers |
| godoc API reference | for mgmt developers |
| prometheus guide | for everyone |
| puppet guide | for puppet sysadmins |
| development | for mgmt developers |
Questions:
Please ask in the community! If you have a well phrased question that might benefit others, consider asking it by sending a patch to the FAQ section. I'll merge your question, and a patch with the answer!
Roadmap:
Feel free to grab one of the straightforward #mgmtlove issues if you're a first time contributor to the project or if you're unsure about what to hack on! Please get involved by working on one of these items or by suggesting something else!
Bugs:
Please set the DEBUG constant in main.go
to true, and post the logs when you report the issue.
Feel free to read my article on debugging golang programs.
Patches:
We'd love to have your patches! Please send them by email, or as a pull request.
On the web:
Read what people are saying and publishing about mgmt!
Happy hacking!