exec

Overview ¶

Package exec provides a filter to edit alerts by an external command.

External commands should read a JSON from stdin, and write JSON to stdout.

If "all" is specified at the filter construction, the input and output shall be a list of kkok.Alert objects exported to JSON. Otherwise, the input and output shall be a kkok.Alert object exported to JSON.

In addition to the standard filter construction parameters, this plugin takes these parameters:

Name      Type       Default   Description
command   []string             Command and arguments.  Required.
timeout   int        5         Seconds before killing the command.
                               If 0, the command will not be killed.

Example snippet for TOML configuration:

[[filter]]
type        = "exec"
id          = "headonly"
label       = "pick the first alert"
all         = true
command     = ["jq", "[.[0]]"]

Another example to process alerts one by one:

[[filter]]
type        = "exec"
id          = "edit_subject"
label       = "add prefix to subjects for emergency alerts"
command     = ["jq", """
if .Routes|contains(["emergency"]) then
    . + {"Title": ("[warn] " + .Title)}
else
    .
end"""]