400b58c0e9
The original string interpolation was based on hil which didn't allow proper escaping, since they used a different escape pattern. Secondly, the golang Unquote function didn't deal with the variable substitution, which meant it had to be performed in a second step. Most importantly, because we did this partial job in Unquote (the fact that is strips the leading and trailing quotes tricked me into thinking I was done with interpolation!) it was impossible to remedy the remaining parts in a second pass with hil. Both operations needs to be done in a single step. This is logical when you aren't tunnel visioned. This patch replaces both of these so that string interpolation works properly. This removes the ability to allow inline function calls in a string, however this was an incidental feature, and it's not clear that having it is a good idea. It also requires you wrap the var name with curly braces. (They are not optional.) This comes with a load of tests, but I think I got some of it wrong, since I'm quite new at ragel. If you find something, please say so =D In any case, this is much better than the original hil implementation, and easy for a new contributor to patch to make the necessary fixes.
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 => $const.res.file.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!
Get involved:
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! There are some lower priority issues and harder issues available in our TODO file. Please have a look.
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!