3317 Warn when Docker image was created from scratch and does not contain /bin/sh

Author: bedla

core/src/main/java/org/testcontainers/containers/wait/internal/InternalCommandPortListeningCheck.java

@@ -2,6 +2,7 @@
 
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
+import org.apache.commons.lang3.StringUtils;
 import org.testcontainers.containers.Container.ExecResult;
 import org.testcontainers.containers.ExecInContainerPattern;
 import org.testcontainers.containers.wait.strategy.WaitStrategyTarget;
@@ -56,6 +57,9 @@ public Boolean call() {
             int exitCode = result.getExitCode();
             if (exitCode != 0 && exitCode != 1) {
                 log.warn("An exception while executing the internal check: {}", result);
+                if (StringUtils.contains(result.getStdout(), "exec: \"/bin/sh\": stat /bin/sh: no such file or directory: unknown")) {
+                    log.warn("Unable to find '/bin/sh'. Does your Dockerfile extends scratch base Dockerfile?");
+                }
             }
             return exitCode == 0;
         } catch (Exception e) {

core/src/main/java/org/testcontainers/images/builder/ImageFromDockerfile.java

@@ -24,12 +24,14 @@
 import org.testcontainers.utility.DockerLoggerFactory;
 import org.testcontainers.utility.ImageNameSubstitutor;
 import org.testcontainers.utility.LazyFuture;
+import org.testcontainers.utility.MountableFile;
 import org.testcontainers.utility.ResourceReaper;
 
 import java.io.IOException;
 import java.io.PipedInputStream;
 import java.io.PipedOutputStream;
 import java.nio.file.Path;
+import java.nio.file.Paths;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
@@ -248,4 +250,14 @@ public ImageFromDockerfile withDockerfile(Path dockerfile) {
         this.dockerfile = Optional.of(dockerfile);
         return this;
     }
+
+    /**
+     * Sets the Dockerfile to be used for this image based on file from classpath.
+     *
+     * @param classpathResource
+     */
+    public ImageFromDockerfile withDockerfileFromClasspath(String classpathResource) {
+        withDockerfile(Paths.get(MountableFile.forClasspathResource(classpathResource).getResolvedPath()));
+        return this;
+    }
 }

core/src/test/java/org/testcontainers/containers/wait/internal/InternalCommandPortListeningCheckWithScratchTest.java

@@ -0,0 +1,107 @@
+package org.testcontainers.containers.wait.internal;
+
+import ch.qos.logback.classic.Level;
+import ch.qos.logback.classic.Logger;
+import ch.qos.logback.classic.spi.ILoggingEvent;
+import ch.qos.logback.core.AppenderBase;
+import lombok.Cleanup;
+import org.apache.commons.lang3.function.FailableRunnable;
+import org.assertj.core.api.ListAssert;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.Parameterized;
+import org.slf4j.LoggerFactory;
+import org.testcontainers.containers.GenericContainer;
+import org.testcontainers.images.builder.ImageFromDockerfile;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.net.URL;
+import java.net.URLConnection;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.stream.Collectors;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@RunWith(Parameterized.class)
+public class InternalCommandPortListeningCheckWithScratchTest {
+    @Parameterized.Parameters(name = "dockerfile.{0} -> {1})")
+    public static Object[][] params() {
+        return new Object[][]{
+            new Object[]{"scratch", false},
+            new Object[]{"alpine", true},
+        };
+    }
+
+    @Parameterized.Parameter(0)
+    public String dockerfileKind;
+
+    @Parameterized.Parameter(1)
+    public boolean expectedEmpty;
+
+    @Test
+    public void testDockerfileFromScratch() throws Throwable {
+        List<ILoggingEvent> logEvents = runForLogEvents(() -> {
+            ImageFromDockerfile image = new ImageFromDockerfile("tc-scratch-wait-hostport-strategy")
+                .withDockerfileFromClasspath("/scratch-wait-strategy-dockerfile/Dockerfile." + dockerfileKind)
+                .withFileFromClasspath("go.mod", "/scratch-wait-strategy-dockerfile/go.mod")
+                .withFileFromClasspath("hello-world.go", "/scratch-wait-strategy-dockerfile/hello-world.go");
+            try (GenericContainer<?> container = new GenericContainer<>(image)
+                .withCommand("/hello-world")
+                .withExposedPorts(8080)
+            ) {
+                container.start();
+
+                // check if ports are correctly published
+                String response = responseFromUrl(new URL("http://" + container.getHost() + ":" + container.getFirstMappedPort() + "/helloworld"));
+                assertThat(response).isEqualTo("Hello, World!");
+            }
+        });
+
+        ListAssert<ILoggingEvent> asserting = assertThat(logEvents.stream()
+            .filter(it -> it.getLevel() == Level.WARN)
+            .filter(it -> "Unable to find '/bin/sh'. Does your Dockerfile extends scratch base Dockerfile?".equals(it.getMessage()))
+            .collect(Collectors.toList())
+        );
+        if (expectedEmpty) {
+            asserting.isEmpty();
+        } else {
+            asserting.isNotEmpty();
+        }
+    }
+
+    private static List<ILoggingEvent> runForLogEvents(FailableRunnable<?> action) throws Throwable {
+        Logger logger = (Logger) LoggerFactory.getLogger(InternalCommandPortListeningCheck.class);
+        TestLogAppender testLogAppender = new TestLogAppender();
+        logger.addAppender(testLogAppender);
+        testLogAppender.start();
+        try {
+            action.run();
+            return testLogAppender.events;
+        } finally {
+            testLogAppender.stop();
+        }
+    }
+
+    private static String responseFromUrl(URL baseUrl) throws IOException {
+        URLConnection urlConnection = baseUrl.openConnection();
+        @Cleanup
+        BufferedReader reader = new BufferedReader(new InputStreamReader(urlConnection.getInputStream()));
+        return reader.readLine();
+    }
+
+    private static class TestLogAppender extends AppenderBase<ILoggingEvent> {
+        private final List<ILoggingEvent> events;
+
+        private TestLogAppender() {
+            this.events = new ArrayList<>();
+        }
+
+        @Override
+        protected void append(ILoggingEvent eventObject) {
+            events.add(eventObject);
+        }
+    }
+}

core/src/test/resources/scratch-wait-strategy-dockerfile/Dockerfile.alpine

@@ -0,0 +1,9 @@
+FROM golang:alpine as app-builder
+WORKDIR /go/src/app
+COPY hello-world.go .
+COPY go.mod .
+RUN CGO_ENABLED=0 go install -ldflags '-extldflags "-static"'
+
+FROM alpine
+COPY --from=app-builder /go/bin/hello-world /hello-world
+ENTRYPOINT ["/hello-world"]

core/src/test/resources/scratch-wait-strategy-dockerfile/Dockerfile.scratch

@@ -0,0 +1,9 @@
+FROM golang:alpine as app-builder
+WORKDIR /go/src/app
+COPY hello-world.go .
+COPY go.mod .
+RUN CGO_ENABLED=0 go install -ldflags '-extldflags "-static"'
+
+FROM scratch
+COPY --from=app-builder /go/bin/hello-world /hello-world
+ENTRYPOINT ["/hello-world"]

core/src/test/resources/scratch-wait-strategy-dockerfile/go.mod

@@ -0,0 +1,3 @@
+module github.com/testcontainers/hello-world
+
+go 1.16

core/src/test/resources/scratch-wait-strategy-dockerfile/hello-world.go

@@ -0,0 +1,15 @@
+package main;
+import (
+    "fmt"
+    "log"
+    "net/http"
+)
+func main() {
+    http.HandleFunc("/helloworld", func(w http.ResponseWriter, r *http.Request){
+        fmt.Fprintf(w, "Hello, World!")
+    })
+    fmt.Printf("Server running (port=8080), route: http://localhost:8080/helloworld\n")
+    if err := http.ListenAndServe(":8080", nil); err != nil {
+        log.Fatal(err)
+    }
+}