refactor GetImageFromDockerfile helper

Author: digital88

src/Testcontainers.KurrentDb/KurrentDbBuilder.cs

@@ -22,7 +22,7 @@ public KurrentDbBuilder()
     /// </summary>
     /// <param name="image">Docker image tag. Available tags can be found here: <see href="https://hub.docker.com/r/kurrentplatform/kurrentdb/tags">https://hub.docker.com/r/kurrentplatform/kurrentdb/tags</see>.</param>
     public KurrentDbBuilder(string image)
-        : this(new KurrentDbConfiguration())ed
+        : this(new KurrentDbConfiguration())
     {
         DockerResourceConfiguration = Init().WithImage(image).DockerResourceConfiguration;
     }

tests/Testcontainers.CockroachDb.Tests/CockroachDbContainerTest.cs

@@ -35,6 +35,11 @@ public async Task ExecScriptReturnsSuccessful()
     public class CockroachDbDefaultFixture(IMessageSink messageSink)
         : DbContainerFixture<CockroachDbBuilder, CockroachDbContainer>(messageSink)
     {
+        protected override CockroachDbBuilder Configure(CockroachDbBuilder builder)
+        {
+            return builder.WithImage(TestSession.GetImageFromDockerfile());
+        }
+
         public override DbProviderFactory DbProviderFactory
             => NpgsqlFactory.Instance;
     }

tests/Testcontainers.Commons/TestSession.cs

@@ -12,17 +12,40 @@ static TestSession()
 
     public static IImage GetImageFromDockerfile(
         string relativePath = "Dockerfile",
-        int lineIndex = 0)
+        string stage = "")
     {
         var fullpath = Path.GetFullPath(relativePath);
         if (!File.Exists(fullpath)) throw new Exception($"Dockerfile not found at '{fullpath}'.");
         var lines = File.ReadAllLines(fullpath);
-        if (lines.Length == 0 || lines.Length <= lineIndex) throw new Exception($"Dockerfile located at '{fullpath}' is empty or shorter than {lineIndex + 1} line(s).");
-        var imageLine = lines[lineIndex];
-        var imageLineSplit = imageLine.Split(" ");
-        if (imageLineSplit.Length < 2) throw new Exception($"Dockerfile located at '{fullpath}' has invalid image tag at line {lineIndex + 1}. The line should start with 'FROM' instruction, followed by space and image tag. For example: 'FROM postgres:17'.");
-        var imageTag = imageLineSplit[1];
-        var image = new DockerImage(imageTag);
-        return image;
+        if (lines.Length == 0) throw new Exception($"Dockerfile located at '{fullpath}' is empty.");
+        if (!string.IsNullOrEmpty(stage)) return FindStage(lines, stage);
+        else return FindFirstTag(lines);
+
+        DockerImage FindFirstTag(IEnumerable<string> lines)
+        {
+            foreach (var line in lines)
+            {
+                if (string.IsNullOrEmpty(line)) continue;
+                var split = line.Split(" ", StringSplitOptions.RemoveEmptyEntries);
+                if (split.Length < 2) continue;
+                var imageTag = split[1];
+                return new DockerImage(imageTag);
+            }
+            throw new Exception($"Failed to find any image tag in Dockerfile located at '{fullpath}'.");
+        }
+
+        DockerImage FindStage(IEnumerable<string> lines, string stage)
+        {
+            foreach (var line in lines)
+            {
+                if (string.IsNullOrEmpty(line)) continue;
+                if (!line.Trim().ToLowerInvariant().EndsWith($"as {stage}")) continue;
+                var split = line.Split(" ", StringSplitOptions.RemoveEmptyEntries);
+                if (split.Length < 2) continue;
+                var imageTag = split[1];
+                return new DockerImage(imageTag);
+            }
+            throw new Exception($"Failed to find image with stage {stage} in Dockerfile located at '{fullpath}'.");
+        }
     }
 }

tests/Testcontainers.Commons/Usings.cs

@@ -1,4 +1,5 @@
 global using System;
+global using System.Collections.Generic;
 global using System.Diagnostics;
 global using System.IO;
 global using System.Text;

tests/Testcontainers.FirebirdSql.Tests/Dockerfile

@@ -1,2 +1,4 @@
 FROM jacobalberty/firebird:v4.0
-#FROM firebirdsql/firebird:5
+FROM jacobalberty/firebird:2.5-sc AS fb2.5-sc
+FROM jacobalberty/firebird:2.5-ss AS fb2.5-ss
+FROM jacobalberty/firebird:v3.0 AS fb3.0

tests/Testcontainers.FirebirdSql.Tests/FirebirdSqlContainerTest.cs

@@ -57,23 +57,23 @@ public class FirebirdSql25ScFixture(IMessageSink messageSink)
         : FirebirdSqlDefaultFixture(messageSink)
     {
         protected override FirebirdSqlBuilder Configure(FirebirdSqlBuilder builder)
-            => builder.WithImage("jacobalberty/firebird:2.5-sc");
+            => builder.WithImage(TestSession.GetImageFromDockerfile(stage: "fb2.5-sc"));
     }
 
     [UsedImplicitly]
     public class FirebirdSql25SsFixture(IMessageSink messageSink)
         : FirebirdSqlDefaultFixture(messageSink)
     {
         protected override FirebirdSqlBuilder Configure(FirebirdSqlBuilder builder)
-            => builder.WithImage("jacobalberty/firebird:2.5-ss");
+            => builder.WithImage(TestSession.GetImageFromDockerfile(stage: "fb2.5-ss"));
     }
 
     [UsedImplicitly]
     public class FirebirdSql30Fixture(IMessageSink messageSink)
         : FirebirdSqlDefaultFixture(messageSink)
     {
         protected override FirebirdSqlBuilder Configure(FirebirdSqlBuilder builder)
-            => builder.WithImage("jacobalberty/firebird:v3.0"); // firebirdsql/firebird:3
+            => builder.WithImage(TestSession.GetImageFromDockerfile(stage: "fb3.0"));
     }
 
     [UsedImplicitly]

tests/Testcontainers.Kafka.Tests/Dockerfile

@@ -1 +1,3 @@
-FROM confluentinc/cp-kafka:7.5.9
+FROM confluentinc/cp-kafka:7.5.9
+FROM apache/kafka:3.9.1 AS kafka3.9.1
+FROM apache/kafka-native:3.9.1 AS kafka-native3.9.1

tests/Testcontainers.Kafka.Tests/KafkaBuilderTest.cs

@@ -6,14 +6,14 @@ public sealed class KafkaBuilderTests
     public void KRaftWithConfluentPre7ThrowsArgumentException()
     {
         const string message = "KRaft is not supported for Confluent Platform images with versions earlier than 7.0.0.";
-        ExpectArgEx(message, () => new KafkaBuilder().WithImage("confluentinc/cp-kafka:6.1.9").WithKRaft().Build());
+        ExpectArgEx(message, () => new KafkaBuilder("confluentinc/cp-kafka:6.1.9").WithKRaft().Build());
     }
 
     [Fact]
     public void ZooKeeperWithApacheKafkaImageThrowsArgumentException()
     {
         const string message = "Local ZooKeeper is not supported for Apache Kafka images. Configure an external ZooKeeper.";
-        ExpectArgEx(message, () => new KafkaBuilder().WithImage("apache/kafka:3.9.1").WithZooKeeper().Build());
+        ExpectArgEx(message, () => new KafkaBuilder("apache/kafka:3.9.1").WithZooKeeper().Build());
     }
 
     private static void ExpectArgEx(string message, Action testCode)

tests/Testcontainers.Kafka.Tests/KafkaContainerTest.cs

@@ -98,8 +98,7 @@ public KafkaZooKeeperConfiguration()
     public sealed class ApacheKafkaConfiguration : KafkaContainerTest
     {
         public ApacheKafkaConfiguration()
-            : base(new KafkaBuilder(TestSession.GetImageFromDockerfile())
-                .WithImage("apache/kafka:3.9.1")
+            : base(new KafkaBuilder(TestSession.GetImageFromDockerfile(stage: "kafka3.9.1"))
                 .Build())
         {
         }
@@ -109,8 +108,7 @@ public ApacheKafkaConfiguration()
     public sealed class ApacheKafkaNativeConfiguration : KafkaContainerTest
     {
         public ApacheKafkaNativeConfiguration()
-            : base(new KafkaBuilder(TestSession.GetImageFromDockerfile())
-                .WithImage("apache/kafka-native:3.9.1")
+            : base(new KafkaBuilder(TestSession.GetImageFromDockerfile(stage: "kafka-native3.9.1"))
                 .Build())
         {
         }

tests/Testcontainers.Keycloak.Tests/Dockerfile

@@ -1 +1,3 @@
-FROM quay.io/keycloak/keycloak:26.4
+FROM quay.io/keycloak/keycloak:26.4
+FROM quay.io/keycloak/keycloak:25.0 AS keycloak25.0
+FROM quay.io/keycloak/keycloak:26.0 AS keycloak26.0