#9 When a finite process exits on error, it will log the entire Docker error log at ERROR level.

Author: robert-bor

src/main/java/nl/_42/boot/docker/utils/DockerFiniteProcessRunner.java

@@ -33,15 +33,18 @@ public DockerFiniteProcessRunner(  String command,
     public DockerOutputResult execute() throws IOException {
         int exitValue = processRunner.execute();
 
-        if (exitValue != 0) {
+        DockerOutputResult result = new DockerOutputResult(
+                readFile(stdOutFilename, Charset.defaultCharset()),
+                readFile(stdErrFilename, Charset.defaultCharset()),
+                exitValue);
+
+        if (result.getExitCode() != 0) {
+            result.logErrLines();
             LOGGER.error("| Docker command: " + command + " failed to execute");
             throw new ExceptionInInitializerError("Docker command: " + command + " failed to execute");
         }
 
-        return new DockerOutputResult(
-                readFile(stdOutFilename, Charset.defaultCharset()),
-                readFile(stdErrFilename, Charset.defaultCharset()),
-                exitValue);
+        return result;
     }
 
     static String readFile(String path, Charset encoding)

src/main/java/nl/_42/boot/docker/utils/DockerOutputResult.java

@@ -1,15 +1,25 @@
 package nl._42.boot.docker.utils;
 
+import org.apache.commons.lang3.StringUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 public class DockerOutputResult {
 
+    private static final Logger LOGGER = LoggerFactory.getLogger(DockerOutputResult.class);
+
     private String stdOut;
     private String stdErr;
     private Integer exitCode;
+    private String[] errLines = new String[0];
 
     public DockerOutputResult(String stdOut, String stdErr, Integer exitCode) {
         this.stdOut = stdOut;
         this.stdErr = stdErr;
         this.exitCode = exitCode;
+        if (!StringUtils.isBlank(stdErr)) {
+            errLines = stdErr.split("\\r\\n|\\n|\\r");
+        }
     }
 
     public String getStdOut() {
@@ -24,4 +34,13 @@ public Integer getExitCode() {
         return exitCode;
     }
 
+    public String[] getErrLines() {
+        return errLines;
+    }
+
+    public void logErrLines() {
+        for (String line : getErrLines()) {
+            LOGGER.error("| > " + line);
+        }
+    }
 }