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此產品有較新版本可以使用。
本繁體中文版使用機器翻譯，譯文僅供參考，若與英文版本牴觸，應以英文版本為準。

執行攔截範例

貢獻者
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請使用下列範例、瞭解如何建立執行掛勾的架構。您可以使用這些hooks做為範本、或做為測試指令碼。

簡單的成功範例

這是一個簡單的勾點、可成功將訊息寫入標準輸出和標準錯誤。

#!/bin/sh

# success_sample.sh
#
# A simple noop success hook script for testing purposes.
#
# args: None
#


#
# Writes the given message to standard output
#
# $* - The message to write
#
msg() {
    echo "$*"
}


#
# Writes the given information message to standard output
#
# $* - The message to write
#
info() {
    msg "INFO: $*"
}

#
# Writes the given error message to standard error
#
# $* - The message to write
#
error() {
    msg "ERROR: $*" 1>&2
}


#
# main
#

# log something to stdout
info "running success_sample.sh"

# exit with 0 to indicate success
info "exit 0"
exit 0

簡單的成功範例（Bash版本）

這是一個簡單的攔截、成功將訊息寫入標準輸出和標準錯誤（寫入Bash）。

#!/bin/bash

# success_sample.bash
#
# A simple noop success hook script for testing purposes.
#
# args: None


#
# Writes the given message to standard output
#
# $* - The message to write
#
msg() {
    echo "$*"
}


#
# Writes the given information message to standard output
#
# $* - The message to write
#
info() {
    msg "INFO: $*"
}

#
# Writes the given error message to standard error
#
# $* - The message to write
#
error() {
    msg "ERROR: $*" 1>&2
}


#
# main
#

# log something to stdout
info "running success_sample.bash"

# exit with 0 to indicate success
info "exit 0"
exit 0

簡單的成功範例（zsh版本）

這是一個簡單的勾點範例、可成功將訊息寫入標準輸出和標準錯誤、並寫入Z Shell。

#!/bin/zsh

# success_sample.zsh
#
# A simple noop success hook script for testing purposes.
#
# args: None
#


#
# Writes the given message to standard output
#
# $* - The message to write
#
msg() {
    echo "$*"
}


#
# Writes the given information message to standard output
#
# $* - The message to write
#
info() {
    msg "INFO: $*"
}

#
# Writes the given error message to standard error
#
# $* - The message to write
#
error() {
    msg "ERROR: $*" 1>&2
}

#
# main
#

# log something to stdout
info "running success_sample.zsh"

# exit with 0 to indicate success
info "exit 0"
exit 0

成功的引數範例

下列範例示範如何在攔截中使用args。

#!/bin/sh

# success_sample_args.sh
#
# A simple success hook script with args for testing purposes.
#
# args: Up to two optional args that are echoed to stdout

#
# Writes the given message to standard output
#
# $* - The message to write
#
msg() {
    echo "$*"
}


#
# Writes the given information message to standard output
#
# $* - The message to write
#
info() {
    msg "INFO: $*"
}

#
# Writes the given error message to standard error
#
# $* - The message to write
#
error() {
    msg "ERROR: $*" 1>&2
}


#
# main
#

# log something to stdout
info "running success_sample_args.sh"


# collect args
arg1=$1
arg2=$2

# output args and arg count to stdout
info "number of args: $#"
info "arg1 ${arg1}"
info "arg2 ${arg2}"

# exit with 0 to indicate success
info "exit 0"
exit 0

快照前/快照後掛機範例

以下範例說明如何將相同的指令碼同時用於快照前和快照後掛勾。

#!/bin/sh

# success_sample_pre_post.sh
#
# A simple success hook script example with an arg for testing purposes
# to demonstrate how the same script can be used for both a prehook and posthook
#
# args: [pre|post]

# unique error codes for every error case
ebase=100
eusage=$((ebase+1))
ebadstage=$((ebase+2))
epre=$((ebase+3))
epost=$((ebase+4))


#
# Writes the given message to standard output
#
# $* - The message to write
#
msg() {
    echo "$*"
}


#
# Writes the given information message to standard output
#
# $* - The message to write
#
info() {
    msg "INFO: $*"
}

#
# Writes the given error message to standard error
#
# $* - The message to write
#
error() {
    msg "ERROR: $*" 1>&2
}


#
# Would run prehook steps here
#
prehook() {
    info "Running noop prehook"
    return 0
}

#
# Would run posthook steps here
#
posthook() {
    info "Running noop posthook"
    return 0
}


#
# main
#

# check arg
stage=$1
if [ -z "${stage}" ]; then
    echo "Usage: $0 <pre|post>"
    exit ${eusage}
fi

if [ "${stage}" != "pre" ] && [ "${stage}" != "post" ]; then
    echo "Invalid arg: ${stage}"
    exit ${ebadstage}
fi

# log something to stdout
info "running success_sample_pre_post.sh"

if [ "${stage}" = "pre" ]; then
    prehook
    rc=$?
    if [ ${rc} -ne 0 ]; then
        error "Error during prehook"
    fi
fi

if [ "${stage}" = "post" ]; then
    posthook
    rc=$?
    if [ ${rc} -ne 0 ]; then
        error "Error during posthook"
    fi
fi

exit ${rc}

故障範例

下列範例示範如何處理攔截式故障。

#!/bin/sh

# failure_sample_arg_exit_code.sh
#
# A simple failure hook script for testing purposes.
#
# args: [the exit code to return]
#


#
# Writes the given message to standard output
#
# $* - The message to write
#
msg() {
    echo "$*"
}


#
# Writes the given information message to standard output
#
# $* - The message to write
#
info() {
    msg "INFO: $*"
}

#
# Writes the given error message to standard error
#
# $* - The message to write
#
error() {
    msg "ERROR: $*" 1>&2
}


#
# main
#

# log something to stdout
info "running failure_sample_arg_exit_code.sh"

argexitcode=$1

# log to stderr
error "script failed, returning exit code ${argexitcode}"

# exit with specified exit code
exit ${argexitcode}

詳細故障範例

下列範例示範如何以更詳細的記錄功能來處理掛機中的失敗。

#!/bin/sh

# failure_sample_verbose.sh
#
# A simple failure hook script with args for testing purposes.
#
# args: [The number of lines to output to stdout]


#
# Writes the given message to standard output
#
# $* - The message to write
#
msg() {
    echo "$*"
}


#
# Writes the given information message to standard output
#
# $* - The message to write
#
info() {
    msg "INFO: $*"
}

#
# Writes the given error message to standard error
#
# $* - The message to write
#
error() {
    msg "ERROR: $*" 1>&2
}


#
# main
#

# log something to stdout
info "running failure_sample_verbose.sh"


# output arg value to stdout
linecount=$1
info "line count ${linecount}"

# write out a line to stdout based on line count arg
i=1
while [ "$i" -le ${linecount} ]; do
    info "This is line ${i} from failure_sample_verbose.sh"
    i=$(( i + 1 ))
done

error "exiting with error code 8"
exit 8

退出程式碼範例失敗

下列範例示範攔截失敗、並顯示結束程式碼。

#!/bin/sh

# failure_sample_arg_exit_code.sh
#
# A simple failure hook script for testing purposes.
#
# args: [the exit code to return]
#


#
# Writes the given message to standard output
#
# $* - The message to write
#
msg() {
    echo "$*"
}


#
# Writes the given information message to standard output
#
# $* - The message to write
#
info() {
    msg "INFO: $*"
}

#
# Writes the given error message to standard error
#
# $* - The message to write
#
error() {
    msg "ERROR: $*" 1>&2
}


#
# main
#

# log something to stdout
info "running failure_sample_arg_exit_code.sh"

argexitcode=$1

# log to stderr
error "script failed, returning exit code ${argexitcode}"

# exit with specified exit code
exit ${argexitcode}

失敗後成功範例

下列範例示範第一次執行時發生掛機故障、但在第二次執行後成功。

#!/bin/sh

# failure_then_success_sample.sh
#
# A hook script that fails on initial run but succeeds on second run for testing purposes.
#
# Helpful for testing retry logic for post hooks.
#
# args: None
#

#
# Writes the given message to standard output
#
# $* - The message to write
#
msg() {
    echo "$*"
}


#
# Writes the given information message to standard output
#
# $* - The message to write
#
info() {
    msg "INFO: $*"
}

#
# Writes the given error message to standard error
#
# $* - The message to write
#
error() {
    msg "ERROR: $*" 1>&2
}


#
# main
#

# log something to stdout
info "running failure_success sample.sh"


if [ -e /tmp/hook-test.junk ] ; then
    info "File does exist.  Removing /tmp/hook-test.junk"
    rm /tmp/hook-test.junk
    info "Second run so returning exit code 0"
    exit 0
else
    info "File does not exist.  Creating /tmp/hook-test.junk"
    echo "test" > /tmp/hook-test.junk
    error "Failed first run, returning exit code 5"
    exit 5
fi