VictoriaMetrics/app/vmselect/graphite/metrics_find_response.qtpl

{% import (
	"sort"
	"strings"

	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
) %}

{% stripspace %}

MetricsFindResponse generates response for /metrics/find .
See https://graphite-api.readthedocs.io/en/latest/api.html#metrics-find
{% func MetricsFindResponse(paths []string, delimiter, format string, addWildcards bool, jsonp string) %}
	{% if jsonp != "" %}{%s= jsonp %}({% endif %}
	{% switch format %}
	{% case "completer" %}
		{%= metricsFindResponseCompleter(paths, delimiter, addWildcards) %}
	{% case "treejson" %}
		{%= metricsFindResponseTreeJSON(paths, delimiter, addWildcards) %}
	{% default %}
		{% code logger.Panicf("BUG: unexpected format=%q", format) %}
	{% endswitch %}
	{% if jsonp != "" %}){% endif %}
{% endfunc %}

{% func metricsFindResponseCompleter(paths []string, delimiter string, addWildcards bool) %}
{
	"metrics":[
		{% for i, path := range paths %}
		{
			"path": {%q= path %},
			"name": {%= metricPathName(path, delimiter) %},
			"is_leaf": {% if strings.HasSuffix(path, delimiter) %}0{% else %}1{% endif %}
		}
		{% if i+1 < len(paths) %},{% endif %}
		{% endfor %}
		{% if addWildcards && len(paths) > 1 %}
		,{
			"name": "*"
		}
		{% endif %}
	]
}
{% endfunc %}

{% func metricsFindResponseTreeJSON(paths []string, delimiter string, addWildcards bool) %}
[
{% code
	if len(paths) > 1 {
		sort.Strings(paths)
		// Substitute `path` and `path<delimiter>` with `path<delimiter><delimiter>`.
		// Such path is treated specially during rendering - see code below for details.
		dst := paths[:1]
		for _, path := range paths[1:] {
			prevPath := dst[len(dst)-1]
			if len(path) == len(prevPath)+1 && strings.HasSuffix(path, delimiter) && strings.HasPrefix(path, prevPath) {
				// The path is equivalent to <prevPath> + <delimiter>
				// Overwrite the prevPath with <path> + <delimiter> as carbonapi does.
				// I.e. the resulting path ends with double delimiter.
				// Such path is treated specially during rendering - see metrics_find_response.qtpl for details.
				dst[len(dst)-1] = path + delimiter
				continue
			}
			dst = append(dst, path)
		}
		paths = dst
	}
%}
	{% for i, path := range paths %}
	{
		{% code
			id := path
			allowChildren := "0"
			isLeaf := "1"
			if strings.HasSuffix(id, delimiter) {
				if strings.HasSuffix(id[:len(id)-1], delimiter) {
					// Special case when id ends with double delimiter.
					// See the code above for details.
					id = id[:len(id)-2]
				}
				allowChildren = "1"
				isLeaf = "0"
			}
		%}
		"id": {%q= id %},
		"text": {%= metricPathName(path, delimiter) %},
		"allowChildren": {%s= allowChildren %},
		"expandable": {%s= allowChildren %},
		"leaf": {%s= isLeaf %}
	}
	{% if i+1 < len(paths) %},{% endif %}
	{% endfor %}
	{% if addWildcards && len(paths) > 1 %}
	,{
		{% code
			path := paths[0]
			for strings.HasSuffix(path, delimiter) {
				path = path[:len(path)-1]
			}
			id := ""
			if n := strings.LastIndexByte(path, delimiter[0]); n >= 0 {
				id = path[:n+1]
			}
			id += "*"

			allowChildren := "0"
			isLeaf := "1"
			for _, path := range paths {
				if strings.HasSuffix(path, delimiter) {
					allowChildren = "1"
					isLeaf = "0"
					break
				}
			}
		%}
		"id": {%q= id %},
		"text": "*",
		"allowChildren": {%s= allowChildren %},
		"expandable": {%s= allowChildren %},
		"leaf": {%s= isLeaf %}
	}
	{% endif %}
]
{% endfunc %}

{% func metricPathName(path, delimiter string) %}
	{% code
		name := path
		for strings.HasSuffix(name, delimiter) {
			name = name[:len(name)-1]
		}
		if n := strings.LastIndexByte(name, delimiter[0]); n >= 0 {
			name = name[n+1:]
		}
	%}
	{%q= name %}
{% endfunc %}

{% endstripspace %}