Ignite about yaml tips and tricks you might not want to use in your config files

1. CfgMgmtCamp Ghent
Julien Pivotto
@roidelapluie
---
yaml magic
February 03 2020

2. ---
yaml enables you to have multiple documents
---
in the same file
Multiple documents
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3. # Those keys have the same value
implicit:
explicit: null
# Those keys have the different values
nothing: null
string: "null"
Values
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4. maybe_countries:
- be
- fr
- nl
- no
# Those mean true and false
[on,off,ON,OFF,yes,Yes,No,no,YES,NO]
Values
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5. # Version numbers
version: 1.3.0
# NOT a version number
version: 1.3
# that's a float!
Values
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6. did you know: spaces are allowed in keys
Keys
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7. did you know: you can have duplicate keys
did you know: this is valid yaml
Keys
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8. .50: keys can be something else than strings
Keys
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9. ? |
keys can have
multiple lines
: yes yes
Keys
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10. didyouknow: another thing about keys
: EMPTY keys are also a thing
Keys
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11. long: |
You can easily write
multi line text in yaml
by using this syntax
You can easily write
multi line text in yaml
by using this syntax
Multiline
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12. long: >
You can easily write
multi line text in yaml
by using this syntax
You can easily write multi line text in yaml by using
Multiline
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13. long: |-
You can easily write
multi line text in yaml
by using this syntax
No newline at the end
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14. long: |+
You can easily write
multi line text in yaml
by using this syntax
You can easily write
multi line text in yaml
by using this syntax
All newlines at the end
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15. set:
? item1
? item2
? item2
set: {item1, item2, item2}
set:
item1:
item2:
Sets
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16. ghent: &belgian_city
country: be
mainland: europe
antwerp: *belgian_city
ghent:
country: be
mainland: europe
antwerp:
country: be
mainland: europe
Anchors
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17. ghent: &belgian_city
country: be
has tld: yes
antwerp:
<<*: belgian_city
has tld: no
ghent:
country: be
has tld: true
antwerp:
country: be
has tld: false
Inheritance
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18. {"note": "maybe at the end we just want json"}
oh yeah
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19. those tips are fun but I'd recommend you keep the
magic far from your prod because the magician on call
might not like reading the yaml spec at 3am :)
use jsonnet
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20. Julien Pivotto
@roidelapluie
roidelapluie@inuits.eu
Essensteenweg 31
2930 Brasschaat
Belgium
Contact:
info@inuits.eu
+32-3-8082105