# Shell

.<https://cloud.google.com/shell/docs/configuring-cloud-shell>

Source: <https://github.com/confluentinc/examples/blob/6.1.0-post/clickstream/ksql/ksql-clickstream-demo/demo/ksql-tables-to-grafana.sh#L18>

```bash
declare -a tables=('click_user_sessions' 'user_ip_activity');
for i in "${tables[@]}"
do
    table_name=$i
    TABLE_NAME=`echo $table_name | tr '[a-z]' '[A-Z]'`

    ## Cleanup existing data

    echo -e "\t-> Remove any existing Elastic search config"  
    curl -s -X "DELETE" "http://$ELASTIC_HOST:9200/""$table_name"  >>/tmp/log.txt 2>&1

done
```

/run

![](/files/-MVSeT6S1SInscKo9jjK)

Library

.<https://github.com/GoogleCloudDataproc/initialization-actions/blob/master/cloud-sql-proxy/cloud-sql-proxy.sh>

```bash
function get_hiveserver_uri() {
  local base_connect_string="jdbc:hive2://localhost:10000"
  if [[ "${KERBEROS_ENABLED}" == 'true' ]]; then
    local hive_principal
    hive_principal=$(get_hive_principal)
    echo "${base_connect_string}/;principal=${hive_principal}"
  else
    echo "${base_connect_string}"
  fi
}
```

cat command

.<https://github.com/GoogleCloudDataproc/initialization-actions/blob/master/cloud-sql-proxy/cloud-sql-proxy.sh#L276-L292>

```bash
cat <<EOF >hive-template.xml
<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<configuration>
  <property>
    <name>javax.jdo.option.ConnectionURL</name>
    <value>jdbc:mysql://localhost:${METASTORE_PROXY_PORT}/${METASTORE_DB}</value>
    <description>the URL of the MySQL database</description>
  </property>
 ...
</configuration>
EOF
```

Permissions

```bash
sudo chown -R $USER:$(id -gn $USER) /home/janardhan/.config
```

.<https://github.com/git/git/blob/e6362826a0409539642a5738db61827e5978e2e4/t/t1301-shared-repo.sh#L74-L84>

```bash
for u in    0660:rw-rw---- \
        0640:rw-r----- \
        0600:rw------- \
        0666:rw-rw-rw- \
        0664:rw-rw-r--
do
    x=$(expr "$u" : ".*:\([rw-]*\)") &&
    y=$(echo "$x" | sed -e "s/w/-/g") &&
    u=$(expr "$u" : "\([0-7]*\)") &&
    git config core.sharedrepository "$u" &&
    umask 0277 &&
```

### history

**`Ctrl`** + **`R`** - Recursive command search

```bash
$ history

clear
echo "hello"
history

# Replay above three commands by !3
# Which tells 3rd line to run
!3

$ history | grep hello
3 echo "hello"
5 history | grep hello


# For timestamp
HISTTIMEFORMAT="%d/%m/%y %T "  # for e.g. “29/02/99 23:59:59”
HISTTIMEFORMAT="%F %T "        # for e.g. “1999-02-29 23:59:59”
```

### Environment variables

#### Windows (PowerShell)

```bash
($env:NODE_ENV = "development") -and (nx build myapp)
```

#### Windows (cmd.exe)

```bash
set "NODE_ENV=development" && nx build myapp
```

#### Unix systems

```bash
NODE_ENV=development nx build myapp
```

### Java Dev Environment

```bash
sudo apt-get update
sudo apt-get install git -y
sudo apt-get install -yq maven

# configure iptable requests from port 80 to 8080
# Java web application listens on 8080
sudo iptables -t nat -A PREROUTING -p tcp --dport 80 -j REDIRECT --to-port 8080
```

### PGP

```bash
PGP_PUB_KEY="generated-key.pgp"
sudo apt-get install rng-tools
sudo rngd -r /dev/urandom
gpg --quick-generate-key --yes j143@protonmail.com
gpg --armor --export "${ATTESTOR_EMAIL}" > ${PGP_PUB_KEY}
```

```bash
GENERATED_PAYLOAD="generated_payload.json"
GENERATED_SIGNATURE="generated_signature.pgp"

PGP_FINGERPRINT="$(gpg --list-keys ${ATTESTOR_EMAIL} | head -2 | tail -1 | awk '{print $1}')"
# ignore gcloud command, focus on generated payload
gcloud beta container binauthz create-signature-payload \
    --artifact-url="${IMAGE_PATH}@${IMAGE_DIGEST}" > ${GENERATED_PAYLOAD}
gpg --local-user "${ATTESTOR_EMAIL}" \
    --armor \
    --output ${GENERATED_SIGNATURE} \
    --sign ${GENERATED_PAYLOAD}
```

### /etc/profile

```
echo "gcloud container clusters get-credentials gke-security-demo-ss \
--zone us-central1-a --project qwiklabs-gcp-03-173a36e0912c" >> /etc/profile
echo "kubectl get clusterrolebinding gke-tutorial-admin-binding &> /dev/null ||
kubectl create clusterrolebinding gke-tutorial-admin-binding \
--clusterrole cluster-admin --user $(gcloud config get-value account)
" >> /etc/profile
```

### Install Ansible terraform

```bash
# Install Ansible package from apt repository.
function getAnsible() {
  local A_EXE="/usr/bin/ansible"
  if [ -e ${A_EXE} ]; then
    echo "${A_EXE} already exists. Exiting."
    return 0
  fi
  echo -n "Installing Ansible ..."
  sudo apt-get -y update &> setup.log
  sudo apt-get -y install software-properties-common &>> setup.log
  sudo apt-add-repository ppa:ansible/ansible -y &>> setup.log
  sudo apt-get -y update &>> setup.log
  sudo apt-get -y install ansible &>> setup.log
  if [ -e ${A_EXE} ]; then
    echo " Done"
  else
    echo " Could not retrieve ${A_EXE}."
  fi
}
# Install Python libraries.
function getPyLibs() {
  echo -n "Installing Python libraries ..."
  sudo pip install pandevice xmltodict &>> setup.log
  echo " Done"
}
# Main program
getAnsible
getPyLibs
```

### sed

```bash
sed -i 's_~/_~_' ./scripts/install/setup_properties.sh
```

![](/files/-MYqzqAgcKGYNZ703Z1i)

![](/files/-MYqzudpp_rcHvfKE3Dn)

```bash
sed -i 's|= container|= k8s_container|g' filename.txt
```

### .sh examples

```bash
#!/bin/bash
sudo apt-get update
sudo apt install git kubectl -y
mkdir /work
chmod o+rwx /work 
cd /work
gsutil cp gs://spls/gsp314/files.tgz .
tar -xzf files.tgz
chmod o+rw -R *
cd /
gsutil cp gs://spls/gsp314/script.sh .
chmod +x script.sh
useradd -m user1
echo "Starting VM provisioning Script"  
su -c "/script.sh student-04-f568db16783a@qwiklabs.net" - user1
if [$? -eq 1]
then
  echo "Script failed. Aborting DM."
  exit 1
else
  echo "Signal the waiter we have completed successfully"
  gcloud beta runtime-config configs create projects/qwiklabs-gcp-04-b0801511bcde/configs/qldm-27678628-3f7856d82ec5c7b5-installer-config --description "Jumphost VM"
  gcloud beta runtime-config configs variables set \
    success/jumphost-waiter \
    success --config-name projects/qwiklabs-gcp-04-b0801511bcde/configs/qldm-27678628-3f7856d82ec5c7b5-installer-config
fi
```

## Powershell

.<https://cloud.google.com/iam/docs/creating-managing-service-account-keys#uploading>

```bash
$cred = gcloud auth application-default print-access-token
$headers = @{ "Authorization" = "Bearer $cred" }

Invoke-WebRequest `
  -Method POST `
  -Headers $headers `
  -ContentType: "application/json; charset=utf-8" `
  -InFile request.json `
  -Uri "https://iam.googleapis.com/v1/projects/PROJECT_ID/serviceAccounts/SA_NAME@PROJECT_ID.iam.gserviceaccount.com/keys:upload" | Select-Object -Expand Content
```

Tips

How to remove a file named `-r`

`-r` is normally a flag, but here it is accidentally created

```bash
[root@machine ~]# ls
-r                        logs-delete.sh           nohup.out
archive                           trash

```

```bash
[root@machine ~]# rm -- -r
rm: remove regular empty file '-r'? y
```


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