Linux| jq command operates on JSON format data

Demonstration content, output to json1 file:

cat >  json1 << EOF
{"tokens":[{"token":"网络","start_offset":0,"end_offset":2,"type":"CN_WORD","position":0},{"token":"不是","start_offset":2,"end_offset":4,"type":"CN_WORD","position":1},{"token":"法外","start_offset":4,"end_offset":6,"type":"CN_WORD","position":2},{"token":"之地","start_offset":6,"end_offset":8,"type":"CN_WORD","position":3}]}
EOF

1. Get the entire JSON object

cat json1 |jq .

Return content:

{
    
    
  "tokens": [
    {
    
    
      "token": "网络",
      "start_offset": 0,
      "end_offset": 2,
      "type": "CN_WORD",
      "position": 0
    },
    {
    
    
      "token": "不是",
      "start_offset": 2,
      "end_offset": 4,
      "type": "CN_WORD",
      "position": 1
    },
    {
    
    
      "token": "法外",
      "start_offset": 4,
      "end_offset": 6,
      "type": "CN_WORD",
      "position": 2
    },
    {
    
    
      "token": "之地",
      "start_offset": 6,
      "end_offset": 8,
      "type": "CN_WORD",
      "position": 3
    }
  ]
}

2. Get all arrays

cat json1 |jq '.[]'

Return content:

[
  {
    
    
    "token": "网络",
    "start_offset": 0,
    "end_offset": 2,
    "type": "CN_WORD",
    "position": 0
  },
  {
    
    
    "token": "不是",
    "start_offset": 2,
    "end_offset": 4,
    "type": "CN_WORD",
    "position": 1
  },
  {
    
    
    "token": "法外",
    "start_offset": 4,
    "end_offset": 6,
    "type": "CN_WORD",
    "position": 2
  },
  {
    
    
    "token": "之地",
    "start_offset": 6,
    "end_offset": 8,
    "type": "CN_WORD",
    "position": 3
  }
]

3. Get tokensthe first index data in the array

cat json1 |jq '.tokens[0]'

Return content:

{
    
    
  "token": "网络",
  "start_offset": 0,
  "end_offset": 2,
  "type": "CN_WORD",
  "position": 0
}

4. Get tokensthe 1st and 2nd index data in the array

cat json1 |jq '.tokens[0:2]'

Return content:

[
  {
    
    
    "token": "网络",
    "start_offset": 0,
    "end_offset": 2,
    "type": "CN_WORD",
    "position": 0
  },
  {
    
    
    "token": "不是",
    "start_offset": 2,
    "end_offset": 4,
    "type": "CN_WORD",
    "position": 1
  }
]

5. Get the value tokensin the first index data in the arraytoken

cat json1 |jq '.tokens[0].token'

Return content:

"网络"

6. Get the value of in tokensthe first index data in the arraytokentype

cat json1 |jq '.tokens[0].token,.tokens[0].type'

It can be abbreviated as:

cat json1 |jq '.tokens[0]|.token,.type'

Return content:

"网络"
"CN_WORD"

7. Get all the values tokens​​in the arraytoken

cat json1 |jq '.tokens[].token'

Return content:

"网络"
"不是"
"法外"
"之地"

8. Iterate over the array and use mapfunctions to perform the same operation on each element in the array.

cat json1 |jq '.[]|map(.token)'

Return content:

[
  "网络",
  "不是",
  "法外",
  "之地"
]

9. Add filter conditions: Get tokensthe data of token == "network" in the array

cat json1 |jq '.tokens[]|select(.token == "网络")'

Return content:

{
    
    
  "token": "网络",
  "start_offset": 0,
  "end_offset": 2,
  "type": "CN_WORD",
  "position": 0
}

10. Add multiple filter conditions: get the data of and tokensin the arraytoken == "网络"type == "CN_WORD"

cat json1 |jq '.tokens[]|select(.token == "网络" and .type == "CN_WORD")'

Return content:

{
    
    
  "token": "网络",
  "start_offset": 0,
  "end_offset": 2,
  "type": "CN_WORD",
  "position": 0
}

11. Add filter conditions: get the data of or tokensin the arraytoken == "网络"token == "法外"

cat json1 |jq '.tokens[]|select(.token == "网络" or .token == "法外")'

Return content:

{
    
    
  "token": "网络",
  "start_offset": 0,
  "end_offset": 2,
  "type": "CN_WORD",
  "position": 0
}
{
    
    
  "token": "法外",
  "start_offset": 4,
  "end_offset": 6,
  "type": "CN_WORD",
  "position": 2
}

12. Get the length of all arrayslength函数

cat json1 |jq '.[]|length'

Return content:

4

13. Modify tokensall token values ​​in the array to TEST

cat json1 |jq '.tokens|map(.token="TEST")'

Return content:

[
  {
    
    
    "token": "TEST",
    "start_offset": 0,
    "end_offset": 2,
    "type": "CN_WORD",
    "position": 0
  },
  {
    
    
    "token": "TEST",
    "start_offset": 2,
    "end_offset": 4,
    "type": "CN_WORD",
    "position": 1
  },
  {
    
    
    "token": "TEST",
    "start_offset": 4,
    "end_offset": 6,
    "type": "CN_WORD",
    "position": 2
  },
  {
    
    
    "token": "TEST",
    "start_offset": 6,
    "end_offset": 8,
    "type": "CN_WORD",
    "position": 3
  }
]

14. Convert to string,tostring函数

cat json1 | jq '.tokens|tostring'

Return content:

"[{
    
    \"token\":\"网络\",\"start_offset\":0,\"end_offset\":2,\"type\":\"CN_WORD\",\"position\":0},{
    
    \"token\":\"不是\",\"start_offset\":2,\"end_offset\":4,\"type\":\"CN_WORD\",\"position\":1},{
    
    \"token\":\"法外\",\"start_offset\":4,\"end_offset\":6,\"type\":\"CN_WORD\",\"position\":2},{
    
    \"token\":\"之地\",\"start_offset\":6,\"end_offset\":8,\"type\":\"CN_WORD\",\"position\":3}]"

15. if-then-elseConditional judgment statement
: Determine tokenwhether the value = network, if it meets the output value = 网络, if it does not, the outputvalue != 网络

cat json1 |jq '.tokens[]|if .token== "网络" then "value = 网络" else "value != 网络" end'

Return content

"value = 网络"
"value != 网络"
"value != 网络"
"value != 网络"