Curl可以从文件中发布二进制数据，所以我一直在使用进程替换和利用文件描述符，每当我需要发布一些讨厌的Curl，仍然想要访问当前shell中的vars。喜欢的东西:

curl "http://localhost:8080" \
-H "Accept: application/json" \
-H "Content-Type:application/json" \
--data @<(cat <<EOF
{
  "me": "$USER",
  "something": $(date +%s)
  }
EOF
)

这看起来像——data @/dev/fd/<some number>，这就像一个正常的文件一样被处理。不管怎样，如果你想看到它在本地工作，只要先运行nc -l 8080，然后在不同的shell中发射上面的命令。你会看到如下内容:

POST / HTTP/1.1
Host: localhost:8080
User-Agent: curl/7.43.0
Accept: application/json
Content-Type:application/json
Content-Length: 43

{  "me": "username",  "something": 1465057519  }

正如你所看到的，你可以在heredoc中调用subshell和引用变量。黑客希望这有助于与快乐 '"'"'""""'''""''.

这个脚本将使用指定的JSON主体向指定的URL发送POST请求，并将服务器的响应输出到控制台:

#!/bin/bash

# Set the URL to send the request to
url='http://example.com/endpoint'

# Set the JSON body of the request
json_data='{"key1": "value1", "key2": "value2"}'

# Make the POST request with the JSON body
response=$(curl -X POST -H "Content-Type: application/json" -d "$json_data" "$url")

echo "Response from server: $response"

您不需要将包含自定义标头的引号传递给curl。另外，数据参数中间的变量应该加引号。

首先，编写一个生成脚本post数据的函数。这让你避免了各种关于shell引用的麻烦，并且比在curl的调用行中输入post数据更容易阅读和维护脚本:

generate_post_data()
{
  cat <<EOF
{
  "account": {
    "email": "$email",
    "screenName": "$screenName",
    "type": "$theType",
    "passwordSettings": {
      "password": "$password",
      "passwordConfirm": "$password"
    }
  },
  "firstName": "$firstName",
  "lastName": "$lastName",
  "middleName": "$middleName",
  "locale": "$locale",
  "registrationSiteId": "$registrationSiteId",
  "receiveEmail": "$receiveEmail",
  "dateOfBirth": "$dob",
  "mobileNumber": "$mobileNumber",
  "gender": "$gender",
  "fuelActivationDate": "$fuelActivationDate",
  "postalCode": "$postalCode",
  "country": "$country",
  "city": "$city",
  "state": "$state",
  "bio": "$bio",
  "jpFirstNameKana": "$jpFirstNameKana",
  "jpLastNameKana": "$jpLastNameKana",
  "height": "$height",
  "weight": "$weight",
  "distanceUnit": "MILES",
  "weightUnit": "POUNDS",
  "heightUnit": "FT/INCHES"
}
EOF
}

然后，在调用curl时很容易使用该函数:

curl -i \
-H "Accept: application/json" \
-H "Content-Type:application/json" \
-X POST --data "$(generate_post_data)" "https://xxx:xxxxx@xxxx-www.xxxxx.com/xxxxx/xxxx/xxxx"

也就是说，这里有一些关于shell引用规则的澄清:

-H参数中的双引号(如-H "foo bar")告诉bash将其中的内容保留为单个参数(即使它包含空格)。

——data参数中的单引号(如——data 'foo bar')执行相同的操作，只不过它们逐字传递所有文本(包括双引号字符和美元符号)。

要在单引号文本中间插入一个变量，您必须结束单引号，然后与双引号变量连接，并重新打开单引号以继续文本:'foo bar'"$variable"'more foo'。

我们可以使用单引号为curl赋值一个变量，并将其他一些变量包装进去

单引号=> ' $variable ' 双引号单引号=> "' $variable '" 一个单+双+单引号=> ' ' ' $variable ' ' ' '

让我们测试每种情况，但首先要注意这个问题，如果我们使用单引号'用于变量赋值，该变量不会被求值。

小心

请注意，赋值是由单引号CURL_DATA='content'完成的

cmd='ls'

CURL_DATA='{
    "cmd": "$cmd",    <===== our variable
    "args": [ "-la" , "/tmp" ],
    "options": {
        "cwd": "/tmp"
    },
   "type": "sync"
}';

echo "$CURL_DATA";

会给我们

{
    "cmd": "$cmd",    <===== we need ls not $cmd
    "args": [ "-la" , "/tmp" ],
    "options": {
        "cwd": "/tmp"
    },
   "type": "sync"
}

单引号' $variable '

一个变量的值被求值 既不是单引号"也不是双引号"

cmd='ls'

CURL_DATA='{
    "cmd": '$cmd',    <===== our variable
    "args": [ "-la" , "/tmp" ],
    "options": {
        "cwd": "/tmp"
    },
   "type": "sync"
}';

echo "$CURL_DATA";

会给我们:

{
    "cmd": ls,    <===== neither 'ls' nor "ls", just ls
    "args": [ "-la" , "/tmp" ],
    "options": {
        "cwd": "/tmp"
    },
   "type": "sync"
}

双引号单引号"' $variable '"

变量被求值 会被双引号包围"

cmd='ls'

CURL_DATA='{
    "cmd": "'$cmd'",    <===== our variable
    "args": [ "-la" , "/tmp" ],
    "options": {
        "cwd": "/tmp"
    },
   "type": "sync"
}';

echo "$CURL_DATA";

会给我们

{
    "cmd": "ls",    <===== we have double quote " variable "
    "args": [ "-la" , "/tmp" ],
    "options": {
        "cwd": "/tmp"
    },
   "type": "sync"
}

一个单+双+单引号=> ' ' ' $variable ' ' ' '

变量被求值 将被一个单引号包围

cmd='ls'

CURL_DATA='{
    "cmd": '"'$cmd'"',
    "args": [ "-la" , "/tmp" ],
    "options": {
        "cwd": "/tmp"
    },
   "type": "sync"
}';

echo "$CURL_DATA";

会给我们

{
    "cmd": 'ls',    <===== we have a single quote ' variable '
    "args": [ "-la" , "/tmp" ],
    "options": {
        "cwd": "/tmp"
    },
   "type": "sync"
}

总结

# no quote at all
$cmd => $cmd

# a double quote (" $variable ")
"$cmd" => "$cmd"

# a single quote (' $variable ')
'$cmd' => ls

# a single quote + a double quote ("' $variable '")
"'$cmd'" => "ls"

# a single-double-single quote ('"' $variable '"')
'"'$cmd'"' => 'ls'

我们应该用哪一个?

由于JSON的键或值需要双引号，我们可以使用:

双引号单引号"' $variable '"

curl

cmd='ls'

CURL_DATA='{
    "cmd": "'$cmd'",
    "args": [ "-la" , "/tmp" ],
    "options": {
        "cwd": "/tmp"
    },
   "type": "sync"
}';

echo "$CURL_DATA" | jq '.'

curl --data "$CURL_DATA" -X POST localhost:3232/cmd | jq '.'

---

注意: 等价于' for a变量求值是'"这意味着我们可以使用'$cmd'而不是使用' '$cmd'，它给我们ls既没有单引号也没有双引号，但如果我们需要应用curl，因为我们需要一个双引号的结果"ls"，并且必须将其包装在另一个双引号=> "'"

这段代码运行良好，但上面的代码可读性更强

cmd='ls'

CURL_DATA='{
    "cmd": "'"$cmd"'",     <===== our variable
    "args": [ "-la" , "/tmp" ],
    "options": {
        "cwd": "/tmp"
    },
   "type": "sync"
}';

echo "$CURL_DATA" | jq '.'

curl --data "$CURL_DATA" -X POST localhost:3232/cmd | jq '.'

会给我们:

{
    "cmd": "ls",    <===== result
    "args": [ "-la" , "/tmp" ],
    "options": {
        "cwd": "/tmp"
    },
   "type": "sync"
}

最后

我们可以用其中任何一种:

    "cmd": "'$cmd'",    <===== will be: "ls"

or

    "cmd": "'"$cmd"'",    <===== will be: "ls" 

$CURL_DATA作为常规变量

curl --data "$CURL_DATA" -X POST localhost:3232/cmd 

使用https://httpbin.org/和内联bash脚本测试的解决方案 1. 对于没有空格的变量，即1: 只需添加'之前和之后$变量替换所需 字符串

for i in {1..3}; do \
  curl -X POST -H "Content-Type: application/json" -d \
    '{"number":"'$i'"}' "https://httpbin.org/post"; \
done

2. 对于带空格的输入: 用额外的“即”来包装变量。“el”:

declare -a arr=("el a" "el b" "el c"); for i in "${arr[@]}"; do \
  curl -X POST -H "Content-Type: application/json" -d \
    '{"elem":"'"$i"'"}' "https://httpbin.org/post"; \
done

哇工作:)

几年之后，如果你使用eval或backtick替换，这可能会帮助到一些人:

postDataJson="{\"guid\":\"$guid\",\"auth_token\":\"$token\"}"

使用sed从响应的开头和结尾去掉引号

$(curl --silent -H "Content-Type: application/json" https://${target_host}/runs/get-work -d ${postDataJson} | sed -e 's/^"//' -e 's/"$//')