Shell Script

Berikut ini kita akan ulas tentang otomatisasi dalam Shell Script dengan Regular expression

Table of Contents Otomatisasi Shell Script Via Dockerfile Via Cloud Build Via Gcloud SSH Via Gcloud Builder Regular expression Pattern Sed Quote

Otomatisasi

Shell Script

$ echo `
#!/bin/sh
 if [ -d /home/chetabahana/.docker/backend ]; then
 	cd /home/chetabahana/.docker/backend && docker-compose down --volumes
 	cd .. && sudo rm -rf /home/chetabahana/.docker/backend
 fi
 gcloud source repos clone github_chetabahana_backend backend
 cd /home/chetabahana/.docker/backend/scripts && chmod +x main.sh && ./main.sh
' > init.sh

$ chmod +x init.sh

Via Dockerfile

• Quickstart for Docker

$ echo `
FROM alpine
COPY init.sh /
CMD ["/init.sh"]
' > Dockerfile

$ gcloud builds submit --tag gcr.io/[PROJECT_ID]/init .
$ gcloud compute --project "chetabahana" ssh --zone "us-central1-c" "backend"
chetabahana@backend:~$ /home/chetabahana/.docker && docker run gcr.io/[PROJECT_ID]/init

Via Cloud Build

• Biaya Cloud Build

Biaya Cloud Build untuk build-menit yang dikonsumsi di atas ambang batas tertentu.

$ echo '
steps:
- name: 'gcr.io/cloud-builders/docker'
  args: [ 'build', '-t', 'gcr.io/$PROJECT_ID/init', '.' ]
images:
- 'gcr.io/$PROJECT_ID/init'
' > cloudbuild.yaml

$ gcloud builds submit --config cloudbuild.yaml .
$ gcloud compute --project "chetabahana" ssh --zone "us-central1-c" "backend"
chetabahana@backend:~$ /home/chetabahana/.docker && docker run gcr.io/[PROJECT_ID]/init

Via Gcloud SSH

steps:
- name: "gcr.io/cloud-builders/gcloud"
  args: ["compute", "ssh", "${_USER_NAME}@${_INSTANCE_NAME}", "--zone", "${_ZONE}", 
  "--command", "cd ${_DOCKER_DIRECTORY} && docker run gcr.io/[PROJECT_ID]/init"]

substitutions:
  _ZONE: us-central1-c
  _USER_NAME: chetabahana # default value
  _INSTANCE_NAME: backend # default value 
  _DOCKER_DIRECTORY: /home/chetabahana/.docker # default value

timeout: "1600s"  

Via Gcloud Builder

steps:
- name: "gcr.io/cloud-builders/gcloud"
  args: ["compute", "ssh", "${_USER_NAME}@${_INSTANCE_NAME}", "--zone", "${_ZONE}", 
  "--command", "cd ${_DOCKER_DIRECTORY} && echo '
#!/bin/sh\n
if [ -d /home/chetabahana/.docker/backend ]; then\n
\tcd /home/chetabahana/.docker/backend && docker-compose down --volumes\n
\tcd .. && sudo rm -rf /home/chetabahana/.docker/backend\n
fi\n
gcloud source repos clone github_chetabahana_backend backend\n
cd /home/chetabahana/.docker/backend/scripts && chmod +x main.sh && ./main.sh\n
#EOF\n
' > init.txt && rm -rf init.sh && mv init.txt init.sh && chmod +x init.sh && ./init.sh"]

substitutions:
  _ZONE: us-central1-c
  _USER_NAME: chetabahana # default value
  _INSTANCE_NAME: backend # default value 
  _DOCKER_DIRECTORY: /home/chetabahana/.docker # default value

timeout: "1600s"  

Regular expression

Pattern

Sed

• GNU sed
• Sed pattern matching

sed 's/ [ ]* / /g'
\_/  | \____/ | |
 |   |    |   | \- g=globally (not just one occurence)
 |   |    |   |
 |   |    |   \- to
 |   |    |
 |   |    \- from
 |   |
 |   \- s=substitute
 |
 \- program sed


The from part:
/ [ ]* /
| \_/| 
|  | \- repeated 0-infinite times
|  |
|   \- group of characters
|
\- boundary

Contoh

• Simpel Tutorial

$ echo 'href="{{ grandchild.url }}"' | \
  sed 's|href="{{ grandchild.url }}"|href="/market{{ grandchild.url }}"|g'
href="/market{{ grandchild.url }}"

$ echo 'href="{{ grandchild.url }}"' | \
  sed 's|href="{{ \([a-zA-Z0-9_]*\).url|href="/market{{ \1.url|g'
href="/market{{ grandchild.url }}"

Quote

• How to escape a double quote inside double quotes?