From 2040519f981f7b734030877d123f9bc484f02bef Mon Sep 17 00:00:00 2001
From: Georgios Andrianakis <geoand@gmail.com>
Date: Fri, 26 Mar 2021 08:51:19 +0200
Subject: [PATCH] Perform absolute basic Dockerfile validation in Openshift s2i
 extension

---
 ...ApplyDockerfileToBuildConfigDecorator.java | 28 +++++++++++++++++--
 1 file changed, 25 insertions(+), 3 deletions(-)

diff --git a/extensions/container-image/container-image-openshift/deployment/src/main/java/io/quarkus/container/image/openshift/deployment/ApplyDockerfileToBuildConfigDecorator.java b/extensions/container-image/container-image-openshift/deployment/src/main/java/io/quarkus/container/image/openshift/deployment/ApplyDockerfileToBuildConfigDecorator.java
index 04425d59b02b4..72a9b96b47a6e 100644
--- a/extensions/container-image/container-image-openshift/deployment/src/main/java/io/quarkus/container/image/openshift/deployment/ApplyDockerfileToBuildConfigDecorator.java
+++ b/extensions/container-image/container-image-openshift/deployment/src/main/java/io/quarkus/container/image/openshift/deployment/ApplyDockerfileToBuildConfigDecorator.java
@@ -1,10 +1,14 @@
 
 package io.quarkus.container.image.openshift.deployment;
 
+import java.io.File;
 import java.io.FileInputStream;
 import java.io.IOException;
 import java.io.InputStream;
+import java.nio.file.Files;
 import java.nio.file.Path;
+import java.util.Optional;
+import java.util.stream.Stream;
 
 import io.dekorate.kubernetes.decorator.NamedResourceDecorator;
 import io.fabric8.kubernetes.api.model.ObjectMeta;
@@ -17,15 +21,33 @@ public class ApplyDockerfileToBuildConfigDecorator extends NamedResourceDecorato
 
     public ApplyDockerfileToBuildConfigDecorator(String name, Path pathToDockerfile) {
         super(name);
-        if (!pathToDockerfile.toFile().exists()) {
+        validate(pathToDockerfile);
+        this.pathToDockerfile = pathToDockerfile;
+    }
+
+    private void validate(Path pathToDockerfile) {
+        File file = pathToDockerfile.toFile();
+        if (!file.exists()) {
             throw new IllegalArgumentException(
                     "Specified Dockerfile: '" + pathToDockerfile.toAbsolutePath().toString() + "' does not exist.");
         }
-        if (!pathToDockerfile.toFile().isFile()) {
+        if (!file.isFile()) {
             throw new IllegalArgumentException(
                     "Specified Dockerfile: '" + pathToDockerfile.toAbsolutePath().toString() + "' is not a normal file.");
         }
-        this.pathToDockerfile = pathToDockerfile;
+
+        try {
+            Stream<String> lines = Files.lines(pathToDockerfile);
+            Optional<String> fromLine = lines.filter(l -> !l.startsWith("#")).map(String::trim)
+                    .filter(l -> l.startsWith("FROM")).findFirst();
+            if (!fromLine.isPresent()) {
+                throw new IllegalArgumentException("Specified Dockerfile: '" + pathToDockerfile.toAbsolutePath().toString()
+                        + "' does not contain a FROM directive");
+            }
+        } catch (IOException e) {
+            throw new IllegalArgumentException(
+                    "Unable to validate specified Dockerfile: '" + pathToDockerfile.toAbsolutePath().toString() + "'");
+        }
     }
 
     @Override