* [saidump]

•	Saidump for DNX-SAI sonic-net#13561

Solution and modification:
To use the redis-db SAVE option to save the snapshot of DB each time and recover later, instead of looping through each entry in the table and saving it.

(1) Updated sonic-buildimage/build_debian.sh, to install Python library rdbtools into the host.
(2) Updated sonic-buildimage/src/sonic-sairedis/saidump/saidump.cpp, add a new option -r, which updates the rdbtools's output-JSON files' format.
(3) Add a new script file: files/scripts/saidump.sh, to do the below steps
  For each ASIC0, such as ASIC0,

  1. Save the Redis data.
  sudo sonic-db-cli -n asic$1 SAVE > /dev/null

  2. Move dump files to /var/run/redisX/
  docker exec database$1 sh -c "mv /var/lib/redis/dump.rdb /var/run/redis$1/"

  3. Run rdb command to convert the dump files into JSON files
  sudo python /usr/local/bin/rdb --command json  /var/run/redis$1/dump.rdb | sudo tee /var/run/redis$1/dump.json > /dev/null

  4. Run saidump -r to update the JSON files' format as same as the saidump before. Then we can get the saidump result in standard output.
  docker exec syncd$1 sh -c "saidump -r /var/run/redis$1/dump.json"

  5. clear
  sudo rm -f /var/run/redis$1/dump.rdb
  sudo rm -f /var/run/redis$1/dump.json

(4) Update sonic-buildimage/src/sonic-utilities/scripts/generate_dump, replace saidump with saidump.sh

build_debian.sh

@@ -729,6 +729,22 @@ SONIC_VERSION_CACHE=${SONIC_VERSION_CACHE}  \
 	DBGOPT="${DBGOPT}" \
 	scripts/collect_host_image_version_files.sh $CONFIGURED_ARCH $IMAGE_DISTRO $TARGET_PATH $FILESYSTEM_ROOT
 
+# Install libc6-dev and python3-dev for compiling python-lzf
+sudo LANG=C chroot $FILESYSTEM_ROOT apt-get -y install libc6-dev python3-dev
+
+# Install python-lzf
+sudo https_proxy=$https_proxy LANG=C chroot $FILESYSTEM_ROOT pip3 install 'python-lzf==0.2.4'
+
+# Install rdbtools
+sudo https_proxy=$https_proxy LANG=C chroot $FILESYSTEM_ROOT pip3 install 'rdbtools==0.1.15'
+
+# Uninstall libc6-dev and python3-dev for compiling python-lzf
+sudo LANG=C DEBIAN_FRONTEND=noninteractive chroot $FILESYSTEM_ROOT apt-get -y remove libc6-dev 
+sudo LANG=C DEBIAN_FRONTEND=noninteractive chroot $FILESYSTEM_ROOT apt-get -y remove python3-dev
+
+## Copy saidump.sh
+sudo cp ./files/scripts/saidump.sh $FILESYSTEM_ROOT/usr/local/bin/saidump.sh
+sudo chmod +x $FILESYSTEM_ROOT/usr/local/bin/saidump.sh
 # Remove GCC
 sudo LANG=C DEBIAN_FRONTEND=noninteractive chroot $FILESYSTEM_ROOT apt-get -y remove gcc
 

files/scripts/saidump.sh

@@ -0,0 +1,33 @@
+#!/bin/bash
+
+save_saidump_by_rdb() {
+  #1. Save the Redis data.
+  sudo sonic-db-cli -n asic$1 SAVE > /dev/null
+  #2. Move dump files to /var/run/redisX/
+  docker exec database$1 sh -c "mv /var/lib/redis/dump.rdb /var/run/redis$1/"
+  #3. Run rdb command to convert the dump files into JSON files
+  sudo python /usr/local/bin/rdb --command json  /var/run/redis$1/dump.rdb | sudo tee /var/run/redis$1/dump.json > /dev/null
+  #4. Run saidump -r to update the JSON files' format as same as the saidump before. Then we can get the saidump result in standard output.
+  docker exec syncd$1 sh -c "saidump -r /var/run/redis$1/dump.json"
+  #5. clear
+  sudo rm -f /var/run/redis$1/dump.rdb
+  sudo rm -f /var/run/redis$1/dump.json
+}
+
+NUM_ASICS=`python -c 'from sonic_py_common.multi_asic import get_num_asics; print(get_num_asics())'`
+
+
+if (( $# == 0 &&  $NUM_ASICS == 1 )); then
+  save_saidump_by_rdb
+#validate if the argument is an integer  
+elif [[ "$1" =~ [0-9]+ ]] && (( $# == 1 && $1 >= 0  && $1 < $NUM_ASICS )) ; then
+    save_saidump_by_rdb $1
+else
+  echo "The number of ASICS is $NUM_ASICS."
+  echo "Usage:"
+  echo "saidump.sh <ASIC Index> or NULL"
+  echo "           <ASIC Index> should be 0 ~ NUM_ASICS."
+  echo "           E.g. \"saidump.sh 1\" is OK when NUMASICS is 2."
+  echo "           NULL"
+  echo "           E.g. \"saidump.sh\" is OK when NUMASICS is 1."
+fi