Credential types and storage in Jenkins - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to specify the credential type for a username and password in Jenkins pipeline.

Jenkins

withCredentials([usernamePassword(credentialsId: 'my-creds', usernameVariable: 'USER', passwordVariable: '[1]')]) { echo "User is $USER" }

Drag options to blanks, or click blank then click option'

APASSWORD

BPASS

CSECRET

DTOKEN

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'PASS' or 'TOKEN' which are not recognized variable names in this context.

The passwordVariable must be set to 'PASSWORD' to correctly map the password from the credentials.

2fill in blank

medium

Complete the code to use a secret text credential in a Jenkins pipeline.

Jenkins

withCredentials([string(credentialsId: 'api-key', variable: '[1]')]) { echo "Key is $API_KEY" }

Drag options to blanks, or click blank then click option'

AAPIKEY

BSECRET

CKEY

DAPI_KEY

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'APIKEY' without underscore does not match the echo statement.

The variable name should match the usage in the echo statement, which is API_KEY.

3fill in blank

hard

Fix the error in the Jenkins pipeline code to correctly use SSH private key credentials.

Jenkins

withCredentials([sshUserPrivateKey(credentialsId: 'ssh-creds', keyFileVariable: '[1]', usernameVariable: 'SSH_USER')]) { sh 'ssh -i $SSH_KEY $SSH_USER@host' }

Drag options to blanks, or click blank then click option'

AKEY_FILE

BSSH_PRIVATE_KEY

CSSH_KEY

DPRIVATE_KEY

Attempts:

3 left

💡 Hint

Common Mistakes

Using a variable name different from the one used in the shell command.

The keyFileVariable must be SSH_KEY to match the shell command usage.

4fill in blank

hard

Fill both blanks to create a Jenkins pipeline snippet that uses a certificate credential.

Jenkins

withCredentials([certificate(credentialsId: '[1]', keystoreVariable: '[2]', passwordVariable: 'CERT_PASS')]) { echo "Using keystore $KEYSTORE" }

Drag options to blanks, or click blank then click option'

Acert-id

Bkeystore

Cstore

Dcert-store

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'cert-store' or 'store' which do not match the echo variable.

The credentialsId should be the ID of the certificate, here 'cert-id'. The keystoreVariable should be 'keystore' to match the echo statement.

5fill in blank

hard

Fill all three blanks to create a Jenkins pipeline snippet that uses a Docker registry credential.

Jenkins

withCredentials([usernamePassword(credentialsId: '[1]', usernameVariable: '[2]', passwordVariable: '[3]')]) { sh 'docker login -u $[2] -p $[3] myregistry.com' }

Drag options to blanks, or click blank then click option'

Adocker-creds

BDOCKER_USER

CDOCKER_PASS

DREGISTRY_PASS

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'REGISTRY_PASS' instead of 'DOCKER_PASS' causes mismatch in variable usage.

The credentialsId is 'docker-creds'. The usernameVariable is 'DOCKER_USER' and the passwordVariable is 'DOCKER_PASS' to match the shell command usage.

Practice

1. Which of the following is NOT a common Jenkins credential type?

easy

A. Database connection string

B. Secret text

C. SSH private key

D. Username and password

Solution

1. Step 1: Review common Jenkins credential types

   Jenkins commonly uses username/password, secret text, SSH keys, and secret files as credential types.

2. Step 2: Identify the option not listed as a credential type

   Database connection string is not a built-in Jenkins credential type; it can be stored as secret text but is not a distinct type.

3. Final Answer:

   Database connection string -> Option A

4. Quick Check:

   Credential types exclude database connection string [OK]

Hint: Remember Jenkins main credential types: user/pass, secret text, SSH keys [OK]

Common Mistakes:

• Confusing secret text with specific data types
• Assuming all data can be a credential type
• Thinking database strings are a separate credential type

2. Which syntax correctly defines a secret text credential in Jenkins pipeline script?

easy

A. credentials('my-secret-text')

B. withCredentials([string(credentialsId: 'my-secret-text', variable: 'SECRET')])

C. secretText('my-secret-text')

D. useSecret('my-secret-text')

Solution

1. Step 1: Understand Jenkins pipeline credential syntax

   Jenkins uses the withCredentials step with a list of credential bindings like string() for secret text.

2. Step 2: Match correct syntax for secret text

   The correct syntax is withCredentials([string(credentialsId: 'id', variable: 'VAR')]) to bind secret text to an environment variable.

3. Final Answer:

   withCredentials([string(credentialsId: 'my-secret-text', variable: 'SECRET')]) -> Option B

4. Quick Check:

   Use withCredentials and string binding for secret text [OK]

Hint: Use withCredentials and string() for secret text in pipelines [OK]

Common Mistakes:

• Using credentials() directly without withCredentials
• Using non-existent secretText() or useSecret() steps
• Confusing variable binding syntax

3. What will be the output of this Jenkins pipeline snippet if the secret text credential 'API_KEY' has value '12345'?

pipeline {
  agent any
  stages {
    stage('Show Secret') {
      steps {
        withCredentials([string(credentialsId: 'API_KEY', variable: 'KEY')]) {
          echo "API Key is: ${KEY}"
        }
      }
    }
  }
}

medium

A. API Key is: 12345

B. API Key is: ${KEY}

C. API Key is:

D. Error: credentials not found

Solution

1. Step 1: Understand withCredentials usage

   The withCredentials block binds the secret text with ID 'API_KEY' to the environment variable 'KEY'.

2. Step 2: Check echo statement output

   The echo command prints the value of ${KEY}, which is '12345' from the secret text credential.

3. Final Answer:

   API Key is: 12345 -> Option A

4. Quick Check:

   Secret text bound to variable prints actual value [OK]

Hint: withCredentials binds secrets to env vars, echo prints actual value [OK]

Common Mistakes:

• Expecting literal ${KEY} instead of variable substitution
• Assuming empty output if secret is set
• Confusing variable name or missing credentials

4. Identify the error in this Jenkins pipeline snippet that tries to use SSH credentials:

pipeline {
  agent any
  stages {
    stage('Use SSH') {
      steps {
        withCredentials([sshUserPrivateKey(credentialsId: 'ssh-key', keyFileVariable: 'KEYFILE')]) {
          sh 'ssh -i $KEYFILE user@host'
        }
      }
    }
  }
}

medium

A. The sh step cannot access environment variables

B. Incorrect use of keyFileVariable instead of usernameVariable

C. sshUserPrivateKey cannot be used in withCredentials

D. Missing usernameVariable in sshUserPrivateKey binding

Solution

1. Step 1: Review sshUserPrivateKey binding requirements

   sshUserPrivateKey requires both credentialsId and usernameVariable to bind the SSH username.

2. Step 2: Identify missing usernameVariable

   The snippet only uses keyFileVariable but misses usernameVariable, which is required for proper binding.

3. Final Answer:

   Missing usernameVariable in sshUserPrivateKey binding -> Option D

4. Quick Check:

   sshUserPrivateKey needs usernameVariable and keyFileVariable [OK]

Hint: sshUserPrivateKey needs usernameVariable and keyFileVariable [OK]

Common Mistakes:

• Omitting usernameVariable in sshUserPrivateKey
• Thinking keyFileVariable alone is enough
• Believing sh cannot use env variables

5. You want to securely use a secret file credential in a Jenkins pipeline to deploy a configuration file. Which is the correct way to access the secret file inside the pipeline?

hard

A. Use credentials('config-file') directly in the shell command

B. Use withCredentials([string(credentialsId: 'config-file', variable: 'CONFIG')]) and echo $CONFIG

C. Use withCredentials([file(credentialsId: 'config-file', variable: 'CONFIG')]) and refer to $CONFIG path

D. Store the file content as secret text and write it manually in the pipeline

Solution

1. Step 1: Understand secret file credential usage

   Secret files are accessed by binding them to a file path variable using file() in withCredentials.

2. Step 2: Use the file path variable in pipeline steps

   The variable (e.g., CONFIG) holds the path to the secret file, which can be used in shell commands safely.

3. Final Answer:

   Use withCredentials([file(credentialsId: 'config-file', variable: 'CONFIG')]) and refer to $CONFIG path -> Option C

4. Quick Check:

   Secret files bind to file path variables with file() [OK]

Hint: Use file() binding for secret files to get file path [OK]

Common Mistakes:

• Using string() for secret files instead of file()
• Trying to use credentials() directly in shell
• Manually writing file content instead of binding