Merge pull request #8 from reefland/reefland/issue5

Reefland/issue5
reefland · Jun 10, 2024 · 53eac00 · 53eac00
2 parents 1d295ef + 6e1b0d6
commit 53eac00
Show file tree

Hide file tree

Showing 2 changed files with 68 additions and 23 deletions.
diff --git a/README.md b/README.md
@@ -33,7 +33,7 @@ $ cri-purge
 
 * ERROR: ROOT privilege required to access CRICTL binaries.
 
-  cri-purge | Version: 0.1.1 | 06/08/2024 | Richard J. Durso
+  cri-purge.sh | Version: 0.1.2 | 06/10/2024 | Richard J. Durso
 
   List and Purge downloaded cached images from containerd.
   -----------------------------------------------------------------------------
@@ -43,13 +43,14 @@ $ cri-purge
   It will do best effort to honor semantic versioning always leaving the newest
   version of the downloaded image and only purge previous version(s).
 
-  -h,  --help           : This usage statement.
-  -l,  --list           : List cached images and which versions could be purged.
-  -p,  --purge          : List images and PURGE/PRUNE older versioned images.
-  -pd, --purge-dangling : Same as --purge, but include dangling images..
-  -s,  --show-dangling  : List dangling images with '<none>' tag.
+  -h,   --help            : This usage statement.
+  -dp,  --dry-run         : Dry run --purge, Do not actually purge any images.
+  -dpd, --dry-run-dangling: Same as --dry-run, but include dangling images.
+  -l,   --list            : List cached images and purgable versions.
+  -p,   --purge           : List images and PURGE/PRUNE older versioned images.
+  -pd,  --purge-dangling  : Same as --purge, but include dangling images.
+  -s,   --show-dangling   : List dangling images with '<none>' tag.
 
-  By default dangling images with '<none>' tag are not purged.
 ```
 
 ---
@@ -146,6 +147,26 @@ Here `cri-purge.sh` has checked `crictl` and determined hash `3c937764e6f5d` is
 
 ---
 
+### To `dry-run` or `dry-run-dangling`
+
+Dry run will go through all the steps to determine images to be purged, but will NOT actually purge any images.
+
+```shell
+sudo cri-purge --dry-run
+```
+
+* Dry run of versioned image purge process.
+
+```shell
+sudo cri-purge --dry-run-dangling
+```
+
+* Dry run of dangling images (tag: `<none>`) purge process.
+
+The dry-run process will include header output of `DRY-RUN - No images will be purged.`
+
+---
+
 ## Using it with OpenShift (Code Ready Containers)
 
 The steps below have been verified on OpenShift CRC 4.13 on RedHat CoreOS:

diff --git a/cri-purge.sh b/cri-purge.sh
@@ -15,8 +15,8 @@
 #           This script requires root permissions to access the CRICTL binary.
 #
 AUTHOR="Richard J. Durso"
-RELDATE="06/09/2024"
-VERSION="0.1.1"
+RELDATE="06/10/2024"
+VERSION="0.1.2"
 #############################################################################
 
 ###[ Define Variables ]#######################################################
@@ -27,6 +27,9 @@ CRIINFO_CMD="crio-status"
 # Define regex to match images with version of some type 
 IMAGE_VERSION_REGEX="^\S+\s+[\w\-_\.\d]+\s+.*"
 
+# Dry run feature is disabled by default
+DRY_RUN=0
+
 ###[ Routines ]##############################################################
 __usage() {
   echo "
@@ -40,13 +43,13 @@ __usage() {
   It will do best effort to honor semantic versioning always leaving the newest
   version of the downloaded image and only purge previous version(s).
 
-  -h,  --help           : This usage statement.
-  -l,  --list           : List cached images and which versions could be purged.
-  -p,  --purge          : List images and PURGE/PRUNE older versioned images.
-  -pd, --purge-dangling : Same as --purge, but include dangling images.
-  -s,  --show-dangling  : List dangling images with '<none>' tag.
-
-  By default dangling images with '<none>' tag are not purged.
+  -h,   --help            : This usage statement.
+  -dp,  --dry-run         : Dry run --purge, Do not actually purge any images.
+  -dpd, --dry-run-dangling: Same as --dry-run, but include dangling images.
+  -l,   --list            : List cached images and purgable versions.
+  -p,   --purge           : List images and PURGE/PRUNE older versioned images.
+  -pd,  --purge-dangling  : Same as --purge, but include dangling images.
+  -s,   --show-dangling   : List dangling images with '<none>' tag.
 
   "
 }
@@ -142,11 +145,15 @@ __reorder_hash_vales() {
       # See if image has is associated to a running container
       if [ -n "$( ${CRI_CMD} ps --image "$(echo "${IMAGES[$i]}" |awk '{ printf "%s\n", $3 }')" -q)" ];
       then
-        # swap elment $i with last element
-        SWAP="${IMAGES[$elements]}"
-
-        IMAGES[elements]="${IMAGES[$i]}"
-        IMAGES[i]=$SWAP
+        # If last image in array has a version tag, do not replace it.
+        # Try to preserve versions and purge dangling images
+        if [ "$(echo "${IMAGES[$elements]}" | awk '{ print $2 }')" = "<none>" ]; then
+          # swap elment $i with last element
+          SWAP="${IMAGES[$elements]}"
+
+          IMAGES[elements]="${IMAGES[$i]}"
+          IMAGES[i]=$SWAP
+        fi
       fi
     fi
   done
@@ -179,6 +186,7 @@ __process_images() {
   __generate_image_list "${1^^}"
 
   echo
+  ((DRY_RUN)) && echo "DRY-RUN - No images will be purged."
   echo "Total Images: ${TOTAL_CRI_IMAGES} Unique Versioned Images Names: ${TOTAL_UNIQUE_IMAGE_NAMES}"
   echo
   COUNT=0
@@ -212,9 +220,11 @@ __process_images() {
 
           # Remove the Specific Image:TAG, or by a hash (if tag=<none>)
           if [ "$TAG_REF" = "\$3" ]; then
-            ${CRI_CMD} rmi "$(echo "${IMAGES[$i]}" |awk '{ printf "%s\n", $3 }')" > /dev/null 2>&1
+            # Only execute if NOT a dry-run
+            ! ((DRY_RUN)) && ${CRI_CMD} rmi "$(echo "${IMAGES[$i]}" |awk '{ printf "%s\n", $3 }')" > /dev/null 2>&1
           else
-            ${CRI_CMD} rmi "$(echo "${IMAGES[$i]}" |awk '{ printf "%s:%s\n", $1, $2 }')" > /dev/null 2>&1
+            # Only execute if NOT a dry-run
+            ! ((DRY_RUN)) && ${CRI_CMD} rmi "$(echo "${IMAGES[$i]}" |awk '{ printf "%s:%s\n", $1, $2 }')" > /dev/null 2>&1
           fi
         else
           echo "- Purgeable TAG: $( echo "${IMAGES[$i]}" | awk "{ printf \"%s (%s)\n\", $TAG_REF, \$4 }")"
@@ -262,6 +272,20 @@ if [ "$#" -ne 0 ]; then
       __process_images LIST
       exit 0
       ;;
+    -dp|--dry-run)
+      # Enable Dry Run 
+      DRY_RUN=1
+      if [ -d "${IMAGE_STORE}" ]; then
+        __process_images "PURGE"
+      fi
+      ;;
+    -dpd|--dry-run-dangling)
+      # Enable Dry Run 
+      DRY_RUN=1
+      if [ -d "${IMAGE_STORE}" ]; then
+        __process_images "PURGE-DANGLING"
+      fi
+      ;;
     -p|--purge)
       if [ -d "${IMAGE_STORE}" ]; then
         START_DISK_SPACE=$(du -ab "${IMAGE_STORE}" | sort -n -r | head -1 | awk '{ print $1 }')