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Sumit Mukharjee
Sumit Mukharjee

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YAML DataTypes and Real-World Examples

#devops #yaml

This is the continuation of the YAML introduction head over here for part 1.
So let's continue with the remaining portion of YAML.
Key Datatype

Key-Value pairs

"apple" : "I am a red fruit"
1 : "This is a roll number"
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List Datatype

- apple
- mango
- banannananna
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Block Style

cities:
 - new delhi
 - mumbai
 - ahmedabad
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YAML Parsers can be used to check if YAML is valid or not.
One such website is YAMLLINT.
Differentiating Between Documents

cities:
 - new delhi
 - mumbai
 - ahmedabad
 ---
 cities: [new Delhi, mumbai]
 ---
 {mango: "fruit", age:5}
 ...
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--- is used to differentiate the type of document.
... is used to define that document is finished now.

JSON Files
Onlineyamltools is a website for conversion and stuff for YAML files.

YAML FILE 👇

cities:
 - new delhi
 - mumbai
 - ahmedabad
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converted to JSON 👇

{
  "cities": [
    "new delhi",
    "mumbai",
    "ahmedabad"
  ]
}
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Flow Type

 cities: [new Delhi, mumbai]
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This doesn't give an indentation error

Comments
YAML doesn't support multiline comments, we have to use the # sign

# Mango
# Apple
# Grapes
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String Variables

name: Sumit Mukharjee
fruit: "Apple"
job: 'swe'
message: !!str Hello There
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Write a single line in multiple lines

message: >
this will
all be 
in one single line
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same as This will all be in one single line

YAML auto detects data type

Specifying the data types

zero: !!int 0
positiveNum: !!int 45
negativeNum: !!int -45
binaryNum: !!int 0b11001
octalNum: !!int 06574
hexNum: !!int 0x45
commaValue: !!+540_000 # 540,000
exponentialNumbers: 6.023E56
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Float Value:

marks: !!float 56.89
infinity: !!float .inf
noANumber: .nan
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Boolean Value

booleanValues: !!bool No
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Null Value

surname: !!null Null
~: this is a null key
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DateTime in YAML

date: !!timestamp 2022-01-25
india time: 2001-12-15T02:59:43.10 +5:30
no time zone: 2001-12-15T02:59:43.10
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Advanced-Data Type

When some of the sequences will be empty they are known as a sparse sequence.

```sparse seq:

  • hey
  • how
  • Null
  • sup ```

Nested Sequence
sequence inside sequence

 - marks
 - name
 - roll_no
- 
 - simplemarks
 - avgMarks
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Maps DataType
key:value pairs are called map datatype
Nested Maps

```name: Sumit Mukharjee
role:
age: 78
job: student




**Pairs Datatype**
Sometimes one key may require duplicate values




```pair examples: !!pairs
 - job: student
 - job: teacher
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Real World Example

Image description
Storing Above data in XML

<?xml version="1.0" encoding="UTF-8">
<School name="DPS" principal="Someone">
  <Students>
     <Student>
          <rno>23</rno>
          <name>"Sumit"</name>
          <marks>94</marks>
        </Student>
   </Students>
</School>
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** In JSON**

{
    "School": [
        {
            "name": "DPS",
            "principal": "Someone",
            "Students": [
                {
                    "rno": 12,
                    "name": "Sumit Mukharjee",
                    "marks": 67
                }
            ]
        }
    ]
}
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In YAML

  - name: DPS
    principal: Someone
    Students:
      - rno: 12
        name: Sumit Mukharjee
        marks: 67
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This was it. Thanks for reading😊.

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