Merge branch 'os-package-override' into 'main'

Added new environment variable WLSIMG_OS_PACKAGES to allow override of OS packages

See merge request weblogic-cloud/weblogic-image-tool!473

Author: ddsharpe

documentation/site/content/userguide/config.md

@@ -0,0 +1,16 @@
+---
+title: "Configuration"
+date: 2024-04-16T08:00:00-05:00
+draft: false
+weight: 5
+---
+
+The default configuration is typically adequate for common use. But, the following environment variables are provided for
+non-typical use cases when the default values are insufficient.  
+
+### Environment variables
+
+- `WLSIMG_CACHEDIR` - When Image Tool downloads patches, those patches are saved in the cache directory. Setting this variable to another directory overrides the default of the `cache` folder in the user's home directory.
+- `WLSIMG_BUILDER` - During the build process, Image Tool creates a Docker context directory where it will create a Dockerfile and copy necessary files for the container image build. Setting this variable to another directory overrides the default of the user's home directory for the parent folder of the Docker context directory.
+- `WLSIMG_OS_PACKAGES` - There are several packages and libraries that are required by the WebLogic Kubernetes Toolkit. The default packages included at build time are `gzip tar unzip libaio libnsl jq findutils diffutils`. The names for those libraries can be different depending on your preferred Linux distribution or OS version. The value that you provide in this environment variable will be used in place of the default package list.
+

imagetool/src/main/java/com/oracle/weblogic/imagetool/util/DockerfileOptions.java

@@ -7,12 +7,14 @@
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import java.util.StringJoiner;
 import java.util.concurrent.Callable;
 import java.util.stream.Collectors;
+import java.util.stream.Stream;
 
 import com.oracle.weblogic.imagetool.aru.AruPatch;
 import com.oracle.weblogic.imagetool.cli.menu.PackageManagerType;
@@ -35,6 +37,10 @@ public class DockerfileOptions {
     // Default location for the oraInst.loc
     private static final String DEFAULT_INV_LOC = "/u01/oracle";
 
+    private static final List<String> DEFAULT_OS_PACKAGES = Arrays.asList(
+        "gzip", "tar", "unzip", "libaio", "libnsl", "jq", "findutils", "diffutils");
+    private static final String WLSIMG_OS_PACKAGES = System.getenv("WLSIMG_OS_PACKAGES");
+
     private static final String DEFAULT_ORAINV_DIR = "/u01/oracle/oraInventory";
 
     final String buildId;
@@ -964,16 +970,6 @@ public List<String> patches() {
         return patchFilenames;
     }
 
-    /**
-     * Referenced by Dockerfile template, provides additional OS packages supplied by the user.
-     *
-     * @return list of commands as Strings.
-     */
-    @SuppressWarnings("unused")
-    public List<String> osPackages() {
-        return getAdditionalCommandsForSection(AdditionalBuildCommands.PACKAGES);
-    }
-
     /**
      * Referenced by Dockerfile template, provides additional build commands supplied by the user.
      *
@@ -1140,4 +1136,25 @@ public DockerfileOptions buildArgs(String variableName) {
         buildArgs.add(variableName);
         return this;
     }
+
+    /**
+     * Referenced by Dockerfile template, provides a list of packages that the package manager,
+     * like YUM, should install.
+     * @return a list of package names.
+     */
+    @SuppressWarnings("unused")
+    public List<String> osPackages() {
+        List<String> result = new ArrayList<>(32);
+        if (Utils.isEmptyString(WLSIMG_OS_PACKAGES)) {
+            // If the user did not provide a list of OS packages, use the default list
+            result.addAll(DEFAULT_OS_PACKAGES);
+        } else {
+            // When provided in the environment variable, use the list of OS packages provided by the user.
+            result.addAll(Stream.of(WLSIMG_OS_PACKAGES.split(" ")).collect(Collectors.toList()));
+        }
+
+        result.addAll(getAdditionalCommandsForSection(AdditionalBuildCommands.PACKAGES));
+
+        return result;
+    }
 }

imagetool/src/main/resources/docker-files/package-managers.mustache

@@ -6,30 +6,30 @@
 # Ensure necessary OS packages are installed
 {{#useYum}}
     RUN yum -y update \
-    && yum -y --downloaddir={{{tempDir}}} install gzip tar unzip libaio libnsl jq findutils diffutils {{#osPackages}}{{{.}}} {{/osPackages}}\
+    && yum -y --downloaddir={{{tempDir}}} install {{#osPackages}}{{{.}}} {{/osPackages}}\
     && yum -y --downloaddir={{{tempDir}}} clean all \
     && rm -rf /var/cache/yum/* \
     && rm -rf {{{tempDir}}}
 {{/useYum}}
 {{#useDnf}}
     RUN dnf -y update \
-    && dnf -y install gzip tar unzip libaio libnsl jq findutils diffutils {{#osPackages}}{{{.}}} {{/osPackages}}\
+    && dnf -y install {{#osPackages}}{{{.}}} {{/osPackages}}\
     && dnf clean all
 {{/useDnf}}
 {{#useMicroDnf}}
     RUN microdnf -y update \
-    && microdnf -y install gzip tar unzip libaio libnsl jq findutils diffutils shadow-utils {{#osPackages}}{{{.}}} {{/osPackages}}\
+    && microdnf -y install {{#osPackages}}{{{.}}} {{/osPackages}}\
     && microdnf clean all
 {{/useMicroDnf}}
 {{#useMicroDnf8}}
     RUN microdnf update \
-    && microdnf install gzip tar unzip libaio libnsl jq findutils diffutils shadow-utils {{#osPackages}}{{{.}}} {{/osPackages}}\
+    && microdnf install {{#osPackages}}{{{.}}} {{/osPackages}}\
     && microdnf clean all
 {{/useMicroDnf8}}
 {{#useAptGet}}
     RUN apt-get -y update \
     && apt-get -y upgrade \
-    && apt-get -y install gzip tar unzip libaio libnsl jq findutils diffutils {{#osPackages}}{{{.}}} {{/osPackages}}\
+    && apt-get -y install {{#osPackages}}{{{.}}} {{/osPackages}}\
     && apt-get -y clean all
 {{/useAptGet}}
 {{#useApk}}