From eb8cf40bf500dfd3a8347bd390cf9aec1dd458ea Mon Sep 17 00:00:00 2001
From: Guillaume Delacour <gui@iroqwa.org>
Date: Fri, 26 Jun 2020 21:43:44 +0200
Subject: [PATCH] Improve template detection

---
 .automation/test/cfn/cfn_bad_3.json  | 16 ++++++++++++++++
 .automation/test/cfn/cfn_good_3.json | 16 ++++++++++++++++
 Dockerfile                           |  2 +-
 lib/linter.sh                        | 18 ++++++++++++++++--
 4 files changed, 49 insertions(+), 3 deletions(-)
 create mode 100644 .automation/test/cfn/cfn_bad_3.json
 create mode 100644 .automation/test/cfn/cfn_good_3.json

diff --git a/.automation/test/cfn/cfn_bad_3.json b/.automation/test/cfn/cfn_bad_3.json
new file mode 100644
index 00000000..37ae6b3a
--- /dev/null
+++ b/.automation/test/cfn/cfn_bad_3.json
@@ -0,0 +1,16 @@
+{
+   "Resources" : {
+      "myDNSRecord" : {
+         "Type" : "AWS::Route53::RecordSet",
+         "Properties" : {
+            "HostedZoneId" : "Z8VLZEXAMPLE",
+            "Name" : "test.example.com",
+            "ResourceRecords" : [
+               "192.0.2.99"
+            ],
+            "Ttl" : 300,
+            "Type" : "A"
+         }
+      }
+   }
+}
diff --git a/.automation/test/cfn/cfn_good_3.json b/.automation/test/cfn/cfn_good_3.json
new file mode 100644
index 00000000..f8602d7a
--- /dev/null
+++ b/.automation/test/cfn/cfn_good_3.json
@@ -0,0 +1,16 @@
+{
+   "Resources" : {
+      "myDNSRecord" : {
+         "Type" : "AWS::Route53::RecordSet",
+         "Properties" : {
+            "HostedZoneId" : "Z8VLZEXAMPLE",
+            "Name" : "test.example.com",
+            "ResourceRecords" : [
+               "192.0.2.99"
+            ],
+            "TTL" : 300,
+            "Type" : "A"
+         }
+      }
+   }
+}
diff --git a/Dockerfile b/Dockerfile
index e332654c..9806ee49 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -53,7 +53,7 @@ RUN mkdir -p /opt/microsoft/powershell/7 \
 # Run Pip3 Installs #
 #####################
 RUN pip3 --no-cache-dir install --upgrade --no-cache-dir \
-    yamllint pylint yq cfn-lint
+    yamllint pylint yq cfn-lint shyaml
 
 ####################
 # Run NPM Installs #
diff --git a/lib/linter.sh b/lib/linter.sh
index 65f68b93..bf4a78e4 100755
--- a/lib/linter.sh
+++ b/lib/linter.sh
@@ -616,11 +616,25 @@ DetectOpenAPIFile()
 # https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/template-formats.html
 DetectCloudFormationFile()
 {
+  # AWSTemplateFormatVersion is optional
+  # grep -E '("|)AWSTemplateFormatVersion("|):'
   if grep 'AWSTemplateFormatVersion' "${1}" > /dev/null; then
     return 0
-  else
-    return 1
   fi
+  if cat "${1}" | shyaml --quiet get-type AWSTemplateFormatVersion > /dev/null; then
+    return 0
+  fi
+
+  if cat "${1}" | jq -e 'has("Resources")' > /dev/null 2>&1; then
+    if cat "${1}" | jq ".Resources[].Type" 2>/dev/null | grep -q -E "(AWS|Alexa|Custom)"; then
+      return 0
+    fi
+  fi
+  if cat "${1}" | shyaml values-0 Resources | grep -q -E "Type: (AWS|Alexa|Custom)"; then
+    return 0
+  fi
+
+  return 1
 }
 
 ################################################################################