improve trivy operator slack template (#597)

Author: martijnvdp

rego-templates/trivy-operator-slack.rego

@@ -1,20 +1,144 @@
 package postee.trivyoperator.slack
 
-title:=sprintf("Trivy Operator %s Report for - %s", [input.kind, input.metadata.name])
-
-result:= res {
- res:= [
- 	{ "type":"section",
-	  "text": {"type":"mrkdwn","text": sprintf("*CRITICAL:* %d", [input.report.summary.criticalCount])}},
- 	{ "type":"section",
-	  "text": {"type":"mrkdwn","text": sprintf("*HIGH:* %d", [input.report.summary.highCount])}},
- 	{ "type":"section",
-	  "text": {"type":"mrkdwn","text": sprintf("*MEDIUM:* %d", [input.report.summary.mediumCount])}},
- 	{ "type":"section",
-	  "text": {"type":"mrkdwn","text": sprintf("*LOW:* %d", [input.report.summary.lowCount])}},
- 	{ "type":"section",
-	  "text": {"type":"mrkdwn","text": sprintf("*UNKNOWN:* %d", [input.report.summary.unknownCount])}},
- 	{ "type":"section",
-	  "text": {"type":"mrkdwn","text": sprintf("*NONE:* %d", [input.report.summary.noneCount])}},
- ]
-}
+import data.postee.flat_array #converts [[{...},{...}], [{...},{...}]] to [{...},{...},{...},{...}]
+import data.postee.with_default
+
+############################################# Common functions ############################################
+
+# render_sections split collection of cells provided to chunks of 5 rows each and wraps every chunk with section element
+render_sections(rows, caption, headers) = result {
+	count(rows) > 0 # only if some vulnerabilities are found	
+	rows_and_header := array.concat(headers, rows)
+	a := flat_array([s |
+		# code below converts 2 dimension array like [[row1, row2, ... row5], ....]
+		group_size := 10 #it's 5 but every row is represented by 2 items
+		num_chunks := ceil(count(rows_and_header) / group_size) - 1
+		indices := {b | b := numbers.range(0, num_chunks)[_] * group_size}
+		some k
+		fields := [array.slice(rows_and_header, i, i + group_size) | i := indices[_]][k]
+		# builds markdown section based on slice
+
+    	s := with_caption(fields, caption, k)
+	])
+	result := array.concat(a, [{"type": "divider"}])
+}
+
+render_sections(rows, caption, headers) = [] { #do not render section if provided collection is empty
+	count(rows) == 0
+}
+
+with_caption(fields, caption, position) = s {
+    position == 0
+	s := [
+		{
+			"type": "section",
+			"text": {
+				"type": "mrkdwn",
+				"text": caption,
+			},
+		},
+		{
+			"type": "section",
+			"fields": fields,
+		},
+	]
+}
+with_caption(fields, caption, position) = s {
+    position > 0
+	s := [
+		{
+			"type": "section",
+			"fields": fields,
+		},
+	]
+}
+
+
+###########################################################################################################
+
+vln_list(severity) = l {
+	# builds list of rows for section for the given severity
+    some i
+	vlnrb := [r |
+		item := input.report.vulnerabilities[i]
+		vlnname := item.vulnerabilityID
+
+		fxvrsn := with_default(item, "fixedVersion", "none")
+		resource_name = with_default(item, "resource", "none")
+		resource_version = with_default(item, "installedVersion", "none")
+		url = with_default(item, "primaryLink","")
+		item.severity == severity # only items with severity matched
+
+		r := [
+			{"type": "mrkdwn", "text": sprintf("<%s|%s>",[url,vlnname])},
+			{"type": "mrkdwn", "text": concat(" / ", [resource_name, resource_version, fxvrsn])},
+		]
+	]
+
+	caption := sprintf("*%s severity vulnerabilities*", [severity]) #TODO make first char uppercase
+
+	headers := [
+		{"type": "mrkdwn", "text": "*Vulnerability ID*"},
+		{"type": "mrkdwn", "text": "*Resource / Version / Fixed version*"},
+	]
+
+	# split rows and wrap slices with markdown section
+	l := render_sections(flat_array(vlnrb), caption, headers)
+}
+
+image_name := sprintf("%s:%s", [
+	with_default(input.report.artifact,"repository","unknown"),
+	with_default(input.report.artifact,"tag","unknown")
+])
+###########################################################################################################
+postee := with_default(input, "postee", {})
+
+title = sprintf("Vulnerability scan report %s", [image_name]) # title is 
+
+result = res {
+
+	header := [
+		{
+			"type": "header",
+			"text": {
+				"type": "plain_text",
+				"text": sprintf("Vulnerability issue with image:%s in namespace %s",[image_name, with_default(input.metadata,"namespace","unknown")]),
+			},
+		}
+	]
+
+	summary := [
+		{
+			"type": "divider"
+		},
+		{
+			"type": "context",
+			"elements": [
+				{"type": "mrkdwn", "text": "*Summary totals:*"},
+			],
+		},
+		{
+			"type": "context",
+			"elements": [
+				{"type": "mrkdwn", "text": sprintf("Critical: *%d*", [input.report.summary.criticalCount])},
+				{"type": "mrkdwn", "text": sprintf("High: *%d*", [input.report.summary.highCount])},
+				{"type": "mrkdwn", "text": sprintf("Medium: *%d*", [input.report.summary.mediumCount])},
+				{"type": "mrkdwn", "text": sprintf("Low: *%d*", [input.report.summary.lowCount])},
+				{"type": "mrkdwn", "text": sprintf("Unknown: *%d*", [input.report.summary.unknownCount])},
+			],
+		},
+		{
+			"type": "divider"
+		}
+	]
+
+	res := flat_array([
+		header,
+		summary,
+		vln_list("CRITICAL"),
+		vln_list("HIGH"),
+		vln_list("MEDIUM"),
+		vln_list("LOW"),
+		vln_list("UNKNOWN")
+	])
+}