I use this backend now and then, for incremental work (like, use cumin to determine a list of hosts with a problem, then target execution on that list). I'm not clear on why this backend is restricted to openstack backends, but it seems to no longer work even on cloudcumin1001 which is now our preferred host for acting on openstack VMs.
andrew@cloudcumin1001:~$ sudo cumin F{"./bustedresolv.txt"} hostname
Caught InvalidQueryError exception: Unable to parse the query 'F{./bustedresolv.txt}' neither with the default backend 'puppetdb' nor with the global grammar:
puppetdb: Expected end of text, found '{' (at char 1), (line:1, col:2)
global: Expected {Combine:({Combine:({D | K | O | P "{"}) SkipTo:("}") "}"}) | Combine:({"A" ":" W:(ABCD...)}) | {"(" Forward: {Group:({{Combine:({Combine:({D | K | O | P "{"}) SkipTo:("}") "}"}) | Combine:({"A" ":" W:(ABCD...)})} | {{"(" : ...} ")"}}) [Group:({{{{"and not" | "and"} | "xor"} | "or"} {{Combine:({Combine:({D | K | O | P "{"}) SkipTo:("}") "}"}) | Combine:({"A" ":" W:(ABCD...)})} | {{"(" : ...} ")"}}})]...} ")"}}, found 'F' (at char 0), (line:1, col:1)
andrew@cloudcumin1001:~$ sudo cumin --backend openstack F{"./bustedresolv.txt"} hostname
Caught InvalidQueryError exception: Unable to parse the query 'F{./bustedresolv.txt}' neither with the default backend 'openstack' nor with the global grammar:
openstack: Expected {Group:("*") | {Group:(Combine:({W:(abcd...) ":" {quotedString using single or double quotes | W:(0123...)}}))}...}, found 'F' (at char 0), (line:1, col:1)
global: Expected {Combine:({Combine:({D | K | O | P "{"}) SkipTo:("}") "}"}) | Combine:({"A" ":" W:(ABCD...)}) | {"(" Forward: {Group:({{Combine:({Combine:({D | K | O | P "{"}) SkipTo:("}") "}"}) | Combine:({"A" ":" W:(ABCD...)})} | {{"(" : ...} ")"}}) [Group:({{{{"and not" | "and"} | "xor"} | "or"} {{Combine:({Combine:({D | K | O | P "{"}) SkipTo:("}") "}"}) | Combine:({"A" ":" W:(ABCD...)})} | {{"(" : ...} ")"}}})]...} ")"}}, found 'F' (at char 0), (line:1, col:1)Please let me know if I'm just making a syntax error here!