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Update document generation script

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Mike Farah 2021-11-03 15:00:28 +11:00
parent 5bedd759a8
commit a41131816a
34 changed files with 111 additions and 1337 deletions
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2
how-it-works.md
View File

@ -118,4 +118,4 @@ The assignment operator then copies across the value from the RHS to the value o
```yaml
a: 2
b: thing
```
```

100
operators/anchor-and-alias-operators.md
View File

@ -4,12 +4,11 @@ Use the `alias` and `anchor` operators to read and write yaml aliases and anchor
`yq` supports merge aliases (like `<<: *blah`) however this is no longer in the standard yaml spec (1.2) and so `yq` will automatically add the `!!merge` tag to these nodes as it is effectively a custom tag.
## Merge one map
see [https://yaml.org/type/merge.html](https://yaml.org/type/merge.html)
## Merge one map
see https://yaml.org/type/merge.html
Given a sample.yml file of:
```yaml
- &CENTER
x: 1
@ -24,15 +23,11 @@ Given a sample.yml file of:
- !!merge <<: *CENTER
r: 10
```
then
```bash
yq eval '.[4] | explode(.)' sample.yml
```
will output
```yaml
x: 1
y: 2
@ -40,11 +35,9 @@ r: 10
```
## Merge multiple maps
see [https://yaml.org/type/merge.html](https://yaml.org/type/merge.html)
see https://yaml.org/type/merge.html
Given a sample.yml file of:
```yaml
- &CENTER
x: 1
@ -60,15 +53,11 @@ Given a sample.yml file of:
- *CENTER
- *BIG
```
then
```bash
yq eval '.[4] | explode(.)' sample.yml
```
will output
```yaml
r: 10
x: 1
@ -76,11 +65,9 @@ y: 2
```
## Override
see [https://yaml.org/type/merge.html](https://yaml.org/type/merge.html)
see https://yaml.org/type/merge.html
Given a sample.yml file of:
```yaml
- &CENTER
x: 1
@ -98,15 +85,11 @@ Given a sample.yml file of:
- *SMALL
x: 1
```
then
```bash
yq eval '.[4] | explode(.)' sample.yml
```
will output
```yaml
r: 10
x: 1
@ -114,173 +97,125 @@ y: 2
```
## Get anchor
Given a sample.yml file of:
```yaml
a: &billyBob cat
```
then
```bash
yq eval '.a | anchor' sample.yml
```
will output
```yaml
billyBob
```
## Set anchor
Given a sample.yml file of:
```yaml
a: cat
```
then
```bash
yq eval '.a anchor = "foobar"' sample.yml
```
will output
```yaml
a: &foobar cat
```
## Set anchor relatively using assign-update
Given a sample.yml file of:
```yaml
a:
b: cat
```
then
```bash
yq eval '.a anchor |= .b' sample.yml
```
will output
```yaml
a: &cat
b: cat
```
## Get alias
Given a sample.yml file of:
```yaml
b: &billyBob meow
a: *billyBob
```
then
```bash
yq eval '.a | alias' sample.yml
```
will output
```yaml
billyBob
```
## Set alias
Given a sample.yml file of:
```yaml
b: &meow purr
a: cat
```
then
```bash
yq eval '.a alias = "meow"' sample.yml
```
will output
```yaml
b: &meow purr
a: *meow
```
## Set alias to blank does nothing
Given a sample.yml file of:
```yaml
b: &meow purr
a: cat
```
then
```bash
yq eval '.a alias = ""' sample.yml
```
will output
```yaml
b: &meow purr
a: cat
```
## Set alias relatively using assign-update
Given a sample.yml file of:
```yaml
b: &meow purr
a:
f: meow
```
then
```bash
yq eval '.a alias |= .f' sample.yml
```
will output
```yaml
b: &meow purr
a: *meow
```
## Explode alias and anchor
Given a sample.yml file of:
```yaml
f:
a: &a cat
b: *a
```
then
```bash
yq eval 'explode(.f)' sample.yml
```
will output
```yaml
f:
a: cat
@ -288,43 +223,31 @@ f:
```
## Explode with no aliases or anchors
Given a sample.yml file of:
```yaml
a: mike
```
then
```bash
yq eval 'explode(.a)' sample.yml
```
will output
```yaml
a: mike
```
## Explode with alias keys
Given a sample.yml file of:
```yaml
f:
a: &a cat
*a: b
```
then
```bash
yq eval 'explode(.f)' sample.yml
```
will output
```yaml
f:
a: cat
@ -332,9 +255,7 @@ f:
```
## Explode with merge anchors
Given a sample.yml file of:
```yaml
foo: &foo
a: foo_a
@ -355,15 +276,11 @@ foobar:
!!merge <<: *foo
thing: foobar_thing
```
then
```bash
yq eval 'explode(.)' sample.yml
```
will output
```yaml
foo:
a: foo_a
@ -385,11 +302,9 @@ foobar:
```
## Dereference and update a field
\`Use explode with multiply to dereference an object
`Use explode with multiply to dereference an object
Given a sample.yml file of:
```yaml
item_value: &item_value
value: true
@ -400,15 +315,11 @@ thingTwo:
name: item_2
!!merge <<: *item_value
```
then
```bash
yq eval '.thingOne |= explode(.) * {"value": false}' sample.yml
```
will output
```yaml
item_value: &item_value
value: true
@ -419,3 +330,4 @@ thingTwo:
name: item_2
!!merge <<: *item_value
```

82
operators/assign-update.md
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@ -1,15 +1,18 @@
# Assign (Update)
This operator is used to update node values. It can be used in either the:
### plain form: `=`
Which will assign the LHS node values to the RHS node values. The RHS expression is run against the matching nodes in the pipeline.
### relative form: `|=`
This will do a similar thing to the plain form, however, the RHS expression is run against _the LHS nodes_. This is useful for updating values based on old values, e.g. increment.
## Create yaml file
Running
```bash
yq eval --null-input '.a.b = "cat" | .x = "frog"'
```
will output
```yaml
a:
b: cat
@ -17,46 +20,34 @@ x: frog
```
## Update node to be the child value
Given a sample.yml file of:
```yaml
a:
b:
g: foof
```
then
```bash
yq eval '.a |= .b' sample.yml
```
will output
```yaml
a:
g: foof
```
## Double elements in an array
Given a sample.yml file of:
```yaml
- 1
- 2
- 3
```
then
```bash
yq eval '.[] |= . * 2' sample.yml
```
will output
```yaml
- 2
- 4
@ -64,75 +55,55 @@ will output
```
## Update node from another file
Note this will also work when the second file is a scalar (string/number)
Given a sample.yml file of:
```yaml
a: apples
```
And another sample another.yml file of:
```yaml
b: bob
```
then
```bash
yq eval-all 'select(fileIndex==0).a = select(fileIndex==1) | select(fileIndex==0)' sample.yml another.yml
```
will output
```yaml
a:
b: bob
```
## Update node to be the sibling value
Given a sample.yml file of:
```yaml
a:
b: child
b: sibling
```
then
```bash
yq eval '.a = .b' sample.yml
```
will output
```yaml
a: sibling
b: sibling
```
## Updated multiple paths
Given a sample.yml file of:
```yaml
a: fieldA
b: fieldB
c: fieldC
```
then
```bash
yq eval '(.a, .c) = "potatoe"' sample.yml
```
will output
```yaml
a: potatoe
b: fieldB
@ -140,69 +111,53 @@ c: potatoe
```
## Update string value
Given a sample.yml file of:
```yaml
a:
b: apple
```
then
```bash
yq eval '.a.b = "frog"' sample.yml
```
will output
```yaml
a:
b: frog
```
## Update string value via |=
Note there is no difference between `=` and `|=` when the RHS is a scalar
Given a sample.yml file of:
```yaml
a:
b: apple
```
then
```bash
yq eval '.a.b |= "frog"' sample.yml
```
will output
```yaml
a:
b: frog
```
## Update selected results
## Update deeply selected results
Note that the LHS is wrapped in brackets! This is to ensure we dont first filter out the yaml and then update the snippet.
Given a sample.yml file of:
```yaml
a:
b: apple
c: cactus
```
then
```bash
yq eval '(.a[] | select(. == "apple")) = "frog"' sample.yml
```
will output
```yaml
a:
b: frog
@ -210,23 +165,17 @@ a:
```
## Update array values
Given a sample.yml file of:
```yaml
- candy
- apple
- sandy
```
then
```bash
yq eval '(.[] | select(. == "*andy")) = "bogs"' sample.yml
```
will output
```yaml
- bogs
- apple
@ -234,41 +183,30 @@ will output
```
## Update empty object
Given a sample.yml file of:
```yaml
{}
```
then
```bash
yq eval '.a.b |= "bogs"' sample.yml
```
will output
```yaml
{a: {b: bogs}}
```
## Update empty object and array
Given a sample.yml file of:
```yaml
{}
```
then
```bash
yq eval '.a.b.[0] |= "bogs"' sample.yml
```
will output
```yaml
{a: {b: [bogs]}}
```

83
operators/boolean-operators.md
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@ -1,8 +1,8 @@
# Boolean Operators
The `or` and `and` operators take two parameters and return a boolean result.
The `or` and `and` operators take two parameters and return a boolean result.
`not` flips a boolean from true to false, or vice versa.
`not` flips a boolean from true to false, or vice versa.
`any` will return `true` if there are any `true` values in a array sequence, and `all` will return true if _all_ elements in an array are true.
@ -11,37 +11,27 @@ The `or` and `and` operators take two parameters and return a boolean result.
These are most commonly used with the `select` operator to filter particular nodes.
## `or` example
Running
```bash
yq eval --null-input 'true or false'
```
will output
```yaml
true
```
## `and` example
Running
```bash
yq eval --null-input 'true and false'
```
will output
```yaml
false
```
## Matching nodes with select, equals and or
Given a sample.yml file of:
```yaml
- a: bird
b: dog
@ -50,15 +40,11 @@ Given a sample.yml file of:
- a: cat
b: fly
```
then
```bash
yq eval '[.[] | select(.a == "cat" or .b == "dog")]' sample.yml
```
will output
```yaml
- a: bird
b: dog
@ -67,50 +53,36 @@ will output
```
## `any` returns true if any boolean in a given array is true
Given a sample.yml file of:
```yaml
- false
- true
```
then
```bash
yq eval 'any' sample.yml
```
will output
```yaml
true
```
## `any` returns false for an empty array
Given a sample.yml file of:
```yaml
[]
```
then
```bash
yq eval 'any' sample.yml
```
will output
```yaml
false
```
## `any_c` returns true if any element in the array is true for the given condition.
Given a sample.yml file of:
```yaml
a:
- rad
@ -119,65 +91,47 @@ b:
- meh
- whatever
```
then
```bash
yq eval '.[] |= any_c(. == "awesome")' sample.yml
```
will output
```yaml
a: true
b: false
```
## `all` returns true if all booleans in a given array are true
Given a sample.yml file of:
```yaml
- true
- true
```
then
```bash
yq eval 'all' sample.yml
```
will output
```yaml
true
```
## `all` returns true for an empty array
Given a sample.yml file of:
```yaml
[]
```
then
```bash
yq eval 'all' sample.yml
```
will output
```yaml
true
```
## `all_c` returns true if all elements in the array are true for the given condition.
Given a sample.yml file of:
```yaml
a:
- rad
@ -186,114 +140,83 @@ b:
- meh
- 12
```
then
```bash
yq eval '.[] |= all_c(tag == "!!str")' sample.yml
```
will output
```yaml
a: true
b: false
```
## Not true is false
Running
```bash
yq eval --null-input 'true | not'
```
will output
```yaml
false
```
## Not false is true
Running
```bash
yq eval --null-input 'false | not'
```
will output
```yaml
true
```
## String values considered to be true
Running
```bash
yq eval --null-input '"cat" | not'
```
will output
```yaml
false
```
## Empty string value considered to be true
Running
```bash
yq eval --null-input '"" | not'
```
will output
```yaml
false
```
## Numbers are considered to be true
Running
```bash
yq eval --null-input '1 | not'
```
will output
```yaml
false
```
## Zero is considered to be true
Running
```bash
yq eval --null-input '0 | not'
```
will output
```yaml
false
```
## Null is considered to be false
Running
```bash
yq eval --null-input '~ | not'
```
will output
```yaml
true
```

16
operators/collect-into-array.md
View File

@ -2,52 +2,40 @@
This creates an array using the expression between the square brackets.
## Collect empty
Running
```bash
yq eval --null-input '[]'
```
will output
```yaml
[]
```
## Collect single
Running
```bash
yq eval --null-input '["cat"]'
```
will output
```yaml
- cat
```
## Collect many
Given a sample.yml file of:
```yaml
a: cat
b: dog
```
then
```bash
yq eval '[.a, .b]' sample.yml
```
will output
```yaml
- cat
- dog
```

69
operators/comment-operators.md
View File

@ -5,71 +5,51 @@ Use these comment operators to set or retrieve comments.
Like the `=` and `|=` assign operators, the same syntax applies when updating comments:
### plain form: `=`
This will assign the LHS nodes comments to the expression on the RHS. The RHS is run against the matching nodes in the pipeline
### relative form: `|=`
### relative form: `|=`
Similar to the plain form, however the RHS evaluates against each matching LHS node! This is useful if you want to set the comments as a relative expression of the node, for instance its value or path.
## Set line comment
Given a sample.yml file of:
```yaml
a: cat
```
then
```bash
yq eval '.a lineComment="single"' sample.yml
```
will output
```yaml
a: cat # single
```
## Use update assign to perform relative updates
Given a sample.yml file of:
```yaml
a: cat
b: dog
```
then
```bash
yq eval '.. lineComment |= .' sample.yml
```
will output
```yaml
a: cat # cat
b: dog # dog
```
## Set head comment
Given a sample.yml file of:
```yaml
a: cat
```
then
```bash
yq eval '. headComment="single"' sample.yml
```
will output
```yaml
# single
@ -77,21 +57,15 @@ a: cat
```
## Set foot comment, using an expression
Given a sample.yml file of:
```yaml
a: cat
```
then
```bash
yq eval '. footComment=.a' sample.yml
```
will output
```yaml
a: cat
@ -99,106 +73,87 @@ a: cat
```
## Remove comment
Given a sample.yml file of:
```yaml
a: cat # comment
b: dog # leave this
```
then
```bash
yq eval '.a lineComment=""' sample.yml
```
will output
```yaml
a: cat
b: dog # leave this
```
## Remove (strip) all comments
Note the use of `...` to ensure key nodes are included.
Given a sample.yml file of:
```yaml
a: cat # comment
# great
b: # key comment
```
then
```bash
yq eval '... comments=""' sample.yml
```
will output
```yaml
a: cat
b:
```
## Get line comment
Given a sample.yml file of:
```yaml
a: cat # meow
```
then
```bash
yq eval '.a | lineComment' sample.yml
```
will output
```yaml
meow
```
## Get head comment
Given a sample.yml file of:
```yaml
# welcome!
a: cat # meow
# have a great day
```
then
```bash
yq eval '. | headComment' sample.yml
```
will output
```yaml
welcome!
```
## Get foot comment
Given a sample.yml file of:
```yaml
# welcome!
a: cat # meow
# have a great day
```
then
```bash
yq eval '. | footComment' sample.yml
```
will output
```yaml
have a great day
```

33
operators/contains.md
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@ -1,33 +1,27 @@
# Contains
## Array contains array
This returns `true` if the context contains the passed in parameter, and false otherwise.
## Array contains array
Array is equal or subset of
Given a sample.yml file of:
```yaml
- foobar
- foobaz
- blarp
```
then
```bash
yq eval 'contains(["baz", "bar"])' sample.yml
```
will output
```yaml
true
```
## Object included in array
Given a sample.yml file of:
```yaml
"foo": 12
"bar":
@ -36,23 +30,17 @@ Given a sample.yml file of:
- "barp": 12
"blip": 13
```
then
```bash
yq eval 'contains({"bar": [{"barp": 12}]})' sample.yml
```
will output
```yaml
true
```
## Object not included in array
Given a sample.yml file of:
```yaml
"foo": 12
"bar":
@ -61,55 +49,40 @@ Given a sample.yml file of:
- "barp": 12
"blip": 13
```
then
```bash
yq eval 'contains({"foo": 12, "bar": [{"barp": 15}]})' sample.yml
```
will output
```yaml
false
```
## String contains substring
Given a sample.yml file of:
```yaml
foobar
```
then
```bash
yq eval 'contains("bar")' sample.yml
```
will output
```yaml
true
```
## String equals string
Given a sample.yml file of:
```yaml
meow
```
then
```bash
yq eval 'contains("meow")' sample.yml
```
will output
```yaml
true
```

27
operators/create-collect-into-object.md
View File

@ -3,68 +3,50 @@
This is used to construct objects (or maps). This can be used against existing yaml, or to create fresh yaml documents.
## Collect empty object
Running
```bash
yq eval --null-input '{}'
```
will output
```yaml
{}
```
## Wrap (prefix) existing object
Given a sample.yml file of:
```yaml
name: Mike
```
then
```bash
yq eval '{"wrap": .}' sample.yml
```
will output
```yaml
wrap:
name: Mike
```
## Using splat to create multiple objects
Given a sample.yml file of:
```yaml
name: Mike
pets:
- cat
- dog
```
then
```bash
yq eval '{.name: .pets.[]}' sample.yml
```
will output
```yaml
Mike: cat
Mike: dog
```
## Working with multiple documents
Given a sample.yml file of:
```yaml
name: Mike
pets:
@ -76,15 +58,11 @@ pets:
- monkey
- sheep
```
then
```bash
yq eval '{.name: .pets.[]}' sample.yml
```
will output
```yaml
Mike: cat
Mike: dog
@ -93,15 +71,12 @@ Rosey: sheep
```
## Creating yaml from scratch
Running
```bash
yq eval --null-input '{"wrap": "frog"}'
```
will output
```yaml
wrap: frog
```

43
operators/delete.md
View File

@ -3,141 +3,103 @@
Deletes matching entries in maps or arrays.
## Delete entry in map
Given a sample.yml file of:
```yaml
a: cat
b: dog
```
then
```bash
yq eval 'del(.b)' sample.yml
```
will output
```yaml
a: cat
```
## Delete nested entry in map
Given a sample.yml file of:
```yaml
a:
a1: fred
a2: frood
```
then
```bash
yq eval 'del(.a.a1)' sample.yml
```
will output
```yaml
a:
a2: frood
```
## Delete entry in array
Given a sample.yml file of:
```yaml
- 1
- 2
- 3
```
then
```bash
yq eval 'del(.[1])' sample.yml
```
will output
```yaml
- 1
- 3
```
## Delete nested entry in array
Given a sample.yml file of:
```yaml
- a: cat
b: dog
```
then
```bash
yq eval 'del(.[0].a)' sample.yml
```
will output
```yaml
- b: dog
```
## Delete no matches
Given a sample.yml file of:
```yaml
a: cat
b: dog
```
then
```bash
yq eval 'del(.c)' sample.yml
```
will output
```yaml
a: cat
b: dog
```
## Delete matching entries
Given a sample.yml file of:
```yaml
a: cat
b: dog
c: bat
```
then
```bash
yq eval 'del( .[] | select(. == "*at") )' sample.yml
```
will output
```yaml
b: dog
```
## Recursively delete matching keys
Given a sample.yml file of:
```yaml
a:
name: frog
@ -145,17 +107,14 @@ a:
name: blog
age: 12
```
then
```bash
yq eval 'del(.. | select(has("name")).name)' sample.yml
```
will output
```yaml
a:
b:
age: 12
```

31
operators/document-index.md
View File

@ -3,23 +3,17 @@
Use the `documentIndex` operator (or the `di` shorthand) to select nodes of a particular document.
## Retrieve a document index
Given a sample.yml file of:
```yaml
a: cat
---
a: frog
```
then
```bash
yq eval '.a | documentIndex' sample.yml
```
will output
```yaml
0
---
@ -27,23 +21,17 @@ will output
```
## Retrieve a document index, shorthand
Given a sample.yml file of:
```yaml
a: cat
---
a: frog
```
then
```bash
yq eval '.a | di' sample.yml
```
will output
```yaml
0
---
@ -51,70 +39,53 @@ will output
```
## Filter by document index
Given a sample.yml file of:
```yaml
a: cat
---
a: frog
```
then
```bash
yq eval 'select(documentIndex == 1)' sample.yml
```
will output
```yaml
a: frog
```
## Filter by document index shorthand
Given a sample.yml file of:
```yaml
a: cat
---
a: frog
```
then
```bash
yq eval 'select(di == 1)' sample.yml
```
will output
```yaml
a: frog
```
## Print Document Index with matches
Given a sample.yml file of:
```yaml
a: cat
---
a: frog
```
then
```bash
yq eval '.a | ({"match": ., "doc": documentIndex})' sample.yml
```
will output
```yaml
match: cat
doc: 0
match: frog
doc: 1
```

59
operators/entries.md
View File

@ -2,23 +2,17 @@
Similar to the same named functions in `jq` these functions convert to/from an object and an array of key-value pairs. This is most useful for performing operations on keys of maps.
## to\_entries Map
## to_entries Map
Given a sample.yml file of:
```yaml
a: 1
b: 2
```
then
```bash
yq eval 'to_entries' sample.yml
```
will output
```yaml
- key: a
value: 1
@ -26,23 +20,17 @@ will output
value: 2
```
## to\_entries Array
## to_entries Array
Given a sample.yml file of:
```yaml
- a
- b
```
then
```bash
yq eval 'to_entries' sample.yml
```
will output
```yaml
- key: 0
value: a
@ -50,113 +38,84 @@ will output
value: b
```
## to\_entries null
## to_entries null
Given a sample.yml file of:
```yaml
null
```
then
```bash
yq eval 'to_entries' sample.yml
```
will output
```yaml
```
## from\_entries map
## from_entries map
Given a sample.yml file of:
```yaml
a: 1
b: 2
```
then
```bash
yq eval 'to_entries | from_entries' sample.yml
```
will output
```yaml
a: 1
b: 2
```
## from\_entries with numeric key indexes
from\_entries always creates a map, even for numeric keys
## from_entries with numeric key indexes
from_entries always creates a map, even for numeric keys
Given a sample.yml file of:
```yaml
- a
- b
```
then
```bash
yq eval 'to_entries | from_entries' sample.yml
```
will output
```yaml
0: a
1: b
```
## Use with\_entries to update keys
## Use with_entries to update keys
Given a sample.yml file of:
```yaml
a: 1
b: 2
```
then
```bash
yq eval 'with_entries(.key |= "KEY_" + .)' sample.yml
```
will output
```yaml
KEY_a: 1
KEY_b: 2
```
## Use with\_entries to filter the map
## Use with_entries to filter the map
Given a sample.yml file of:
```yaml
a:
b: bird
c:
d: dog
```
then
```bash
yq eval 'with_entries(select(.value | has("b")))' sample.yml
```
will output
```yaml
a:
b: bird
```

31
operators/env-variable-operators.md
View File

@ -3,106 +3,77 @@
This operator is used to handle environment variables usage in path expressions. While environment variables can, of course, be passed in via your CLI with string interpolation, this often comes with complex quote escaping and can be tricky to write and read. Note that there are two forms, `env` which will parse the environment variable as a yaml (be it a map, array, string, number of boolean) and `strenv` which will always parse the argument as a string.
## Read string environment variable
Running
```bash
myenv="cat meow" yq eval --null-input '.a = env(myenv)'
```
will output
```yaml
a: cat meow
```
## Read boolean environment variable
Running
```bash
myenv="true" yq eval --null-input '.a = env(myenv)'
```
will output
```yaml
a: true
```
## Read numeric environment variable
Running
```bash
myenv="12" yq eval --null-input '.a = env(myenv)'
```
will output
```yaml
a: 12
```
## Read yaml environment variable
Running
```bash
myenv="{b: fish}" yq eval --null-input '.a = env(myenv)'
```
will output
```yaml
a: {b: fish}
```
## Read boolean environment variable as a string
Running
```bash
myenv="true" yq eval --null-input '.a = strenv(myenv)'
```
will output
```yaml
a: "true"
```
## Read numeric environment variable as a string
Running
```bash
myenv="12" yq eval --null-input '.a = strenv(myenv)'
```
will output
```yaml
a: "12"
```
## Dynamic key lookup with environment variable
Given a sample.yml file of:
```yaml
cat: meow
dog: woof
```
then
```bash
myenv="cat" yq eval '.[env(myenv)]' sample.yml
```
will output
```yaml
meow
```

41
operators/equals.md
View File

@ -13,23 +13,17 @@ select(.a == .b)
```
## Match string
Given a sample.yml file of:
```yaml
- cat
- goat
- dog
```
then
```bash
yq eval '.[] | (. == "*at")' sample.yml
```
will output
```yaml
true
true
@ -37,23 +31,17 @@ false
```
## Don't match string
Given a sample.yml file of:
```yaml
- cat
- goat
- dog
```
then
```bash
yq eval '.[] | (. != "*at")' sample.yml
```
will output
```yaml
false
false
@ -61,23 +49,17 @@ true
```
## Match number
Given a sample.yml file of:
```yaml
- 3
- 4
- 5
```
then
```bash
yq eval '.[] | (. == 4)' sample.yml
```
will output
```yaml
false
true
@ -85,23 +67,17 @@ false
```
## Dont match number
Given a sample.yml file of:
```yaml
- 3
- 4
- 5
```
then
```bash
yq eval '.[] | (. != 4)' sample.yml
```
will output
```yaml
true
false
@ -109,55 +85,40 @@ true
```
## Match nulls
Running
```bash
yq eval --null-input 'null == ~'
```
will output
```yaml
true
```
## Non exisitant key doesn't equal a value
Given a sample.yml file of:
```yaml
a: frog
```
then
```bash
yq eval 'select(.b != "thing")' sample.yml
```
will output
```yaml
a: frog
```
## Two non existant keys are equal
Given a sample.yml file of:
```yaml
a: frog
```
then
```bash
yq eval 'select(.b == .c)' sample.yml
```
will output
```yaml
a: frog
```

29
operators/file-operators.md
View File

@ -5,75 +5,53 @@ File operators are most often used with merge when needing to merge specific fil
Note that the `fileIndex` operator has a short alias of `fi`.
## Merging files
Note the use of eval-all to ensure all documents are loaded into memory.
```bash
yq eval-all 'select(fi == 0) * select(filename == "file2.yaml")' file1.yaml file2.yaml
```
## Get filename
Given a sample.yml file of:
```yaml
a: cat
```
then
```bash
yq eval 'filename' sample.yml
```
will output
```yaml
sample.yml
```
## Get file index
Given a sample.yml file of:
```yaml
a: cat
```
then
```bash
yq eval 'fileIndex' sample.yml
```
will output
```yaml
0
```
## Get file indices of multiple documents
Given a sample.yml file of:
```yaml
a: cat
```
And another sample another.yml file of:
```yaml
a: cat
```
then
```bash
yq eval-all 'fileIndex' sample.yml another.yml
```
will output
```yaml
0
---
@ -81,21 +59,16 @@ will output
```
## Get file index alias
Given a sample.yml file of:
```yaml
a: cat
```
then
```bash
yq eval 'fi' sample.yml
```
will output
```yaml
0
```

20
operators/has.md
View File

@ -3,24 +3,18 @@
This is operation that returns true if the key exists in a map (or index in an array), false otherwise.
## Has map key
Given a sample.yml file of:
```yaml
- a: yes
- a: ~
- a:
- b: nope
```
then
```bash
yq eval '.[] | has("a")' sample.yml
```
will output
```yaml
true
true
@ -29,11 +23,9 @@ false
```
## Select, checking for existence of deep paths
Simply pipe in parent expressions into `has`
Given a sample.yml file of:
```yaml
- a:
b:
@ -42,15 +34,11 @@ Given a sample.yml file of:
b:
d: dog
```
then
```bash
yq eval '.[] | select(.a.b | has("c"))' sample.yml
```
will output
```yaml
a:
b:
@ -58,25 +46,20 @@ a:
```
## Has array index
Given a sample.yml file of:
```yaml
- []
- [1]
- [1, 2]
- [1, null]
- [1, 2, 3]
```
then
```bash
yq eval '.[] | has(1)' sample.yml
```
will output
```yaml
false
false
@ -84,3 +67,4 @@ true
true
true
```

15
operators/keys.md
View File

@ -1,47 +1,36 @@
# Keys
Use the `keys` operator to return map keys or array indices.
Use the `keys` operator to return map keys or array indices.
## Map keys
Given a sample.yml file of:
```yaml
dog: woof
cat: meow
```
then
```bash
yq eval 'keys' sample.yml
```
will output
```yaml
- dog
- cat
```
## Array keys
Given a sample.yml file of:
```yaml
- apple
- banana
```
then
```bash
yq eval 'keys' sample.yml
```
will output
```yaml
- 0
- 1
```

25
operators/length.md
View File

@ -3,91 +3,68 @@
Returns the lengths of the nodes. Length is defined according to the type of the node.
## String length
returns length of string
Given a sample.yml file of:
```yaml
a: cat
```
then
```bash
yq eval '.a | length' sample.yml
```
will output
```yaml
3
```
## null length
Given a sample.yml file of:
```yaml
a: null
```
then
```bash
yq eval '.a | length' sample.yml
```
will output
```yaml
0
```
## Map length
returns number of entries
Given a sample.yml file of:
```yaml
a: cat
c: dog
```
then
```bash
yq eval 'length' sample.yml
```
will output
```yaml
2
```
## Array length
returns number of elements
Given a sample.yml file of:
```yaml
- 2
- 4
- 6
- 8
```
then
```bash
yq eval 'length' sample.yml
```
will output
```yaml
4
```

102
operators/multiply-merge.md
View File

@ -3,21 +3,18 @@
Like the multiple operator in jq, depending on the operands, this multiply operator will do different things. Currently numbers, arrays and objects are supported.
## Objects and arrays - merging
Objects are merged deeply matching on matching keys. By default, array values override and are not deeply merged.
Note that when merging objects, this operator returns the merged object (not the parent). This will be clearer in the examples below.
### Merge Flags
You can control how objects are merged by using one or more of the following flags. Multiple flags can be used together, e.g. `.a *+? .b`. See examples below
You can control how objects are merged by using one or more of the following flags. Multiple flags can be used together, e.g. `.a *+? .b`. See examples below
* `+` to append arrays
* `?` to only merge existing fields
* `d` to deeply merge arrays
- `+` to append arrays
- `?` to only merge existing fields
- `d` to deeply merge arrays
### Merging files
Note the use of `eval-all` to ensure all documents are loaded into memory.
```bash
@ -25,23 +22,17 @@ yq eval-all 'select(fileIndex == 0) * select(fileIndex == 1)' file1.yaml file2.y
```
## Multiply integers
Running
```bash
yq eval --null-input '3 * 4'
```
will output
```yaml
12
```
## Merge objects together, returning merged result only
Given a sample.yml file of:
```yaml
a:
field: me
@ -51,15 +42,11 @@ b:
g: wizz
fieldB: dog
```
then
```bash
yq eval '.a * .b' sample.yml
```
will output
```yaml
field:
g: wizz
@ -68,9 +55,7 @@ fieldB: dog
```
## Merge objects together, returning parent object
Given a sample.yml file of:
```yaml
a:
field: me
@ -80,15 +65,11 @@ b:
g: wizz
fieldB: dog
```
then
```bash
yq eval '. * {"a":.b}' sample.yml
```
will output
```yaml
a:
field:
@ -102,23 +83,17 @@ b:
```
## Merge keeps style of LHS
Given a sample.yml file of:
```yaml
a: {things: great}
b:
also: "me"
```
then
```bash
yq eval '. * {"a":.b}' sample.yml
```
will output
```yaml
a: {things: great, also: "me"}
b:
@ -126,9 +101,7 @@ b:
```
## Merge arrays
Given a sample.yml file of:
```yaml
a:
- 1
@ -139,15 +112,11 @@ b:
- 4
- 5
```
then
```bash
yq eval '. * {"a":.b}' sample.yml
```
will output
```yaml
a:
- 3
@ -160,9 +129,7 @@ b:
```
## Merge, only existing fields
Given a sample.yml file of:
```yaml
a:
thing: one
@ -171,24 +138,18 @@ b:
missing: two
thing: two
```
then
```bash
yq eval '.a *? .b' sample.yml
```
will output
```yaml
thing: two
cat: frog
```
## Merge, appending arrays
Given a sample.yml file of:
```yaml
a:
array:
@ -203,15 +164,11 @@ b:
- animal: cat
value: banana
```
then
```bash
yq eval '.a *+ .b' sample.yml
```
will output
```yaml
array:
- 1
@ -224,9 +181,7 @@ value: banana
```
## Merge, only existing fields, appending arrays
Given a sample.yml file of:
```yaml
a:
thing:
@ -239,15 +194,11 @@ b:
another:
- 1
```
then
```bash
yq eval '.a *?+ .b' sample.yml
```
will output
```yaml
thing:
- 1
@ -257,11 +208,9 @@ thing:
```
## Merge, deeply merging arrays
Merging arrays deeply means arrays are merge like objects, with indexes as their key. In this case, we merge the first item in the array, and do nothing with the second.
Given a sample.yml file of:
```yaml
a:
- name: fred
@ -272,15 +221,11 @@ b:
- name: fred
age: 34
```
then
```bash
yq eval '.a *d .b' sample.yml
```
will output
```yaml
- name: fred
age: 34
@ -289,11 +234,13 @@ will output
```
## Merge arrays of objects together, matching on a key
It's a complex command, the trickyness comes from needing to have the right context in the expressions.
First we save the second array into a variable '$two' which lets us reference it later.
We then need to update the first array. We will use the relative update (|=) because we need to update relative to the current element of the array in the LHS in the RHS expression.
We set the current element of the first array as $cur. Now we multiply (merge) $cur with the matching entry in $two, by passing $two through a select filter.
It's a complex command, the trickyness comes from needing to have the right context in the expressions. First we save the second array into a variable '$two' which lets us reference it later. We then need to update the first array. We will use the relative update (|=) because we need to update relative to the current element of the array in the LHS in the RHS expression. We set the current element of the first array as $cur. Now we multiply (merge) $cur with the matching entry in $two, by passing $two through a select filter.
Given a sample.yml file of:
```yaml
- a: apple
b: appleB
@ -302,9 +249,7 @@ Given a sample.yml file of:
- a: banana
b: bananaB
```
And another sample another.yml file of:
```yaml
- a: banana
c: bananaC
@ -313,15 +258,11 @@ And another sample another.yml file of:
- a: dingo
c: dingoC
```
then
```bash
yq eval-all '(select(fi==1) | .[]) as $two | select(fi==0) | .[] |= (. as $cur | $cur * ($two | select(.a == $cur.a)))' sample.yml another.yml
```
will output
```yaml
- a: apple
b: appleB2
@ -333,22 +274,16 @@ will output
```
## Merge to prefix an element
Given a sample.yml file of:
```yaml
a: cat
b: dog
```
then
```bash
yq eval '. * {"a": {"c": .a}}' sample.yml
```
will output
```yaml
a:
c: cat
@ -356,9 +291,7 @@ b: dog
```
## Merge with simple aliases
Given a sample.yml file of:
```yaml
a: &cat
c: frog
@ -367,24 +300,18 @@ b:
c:
g: thongs
```
then
```bash
yq eval '.c * .b' sample.yml
```
will output
```yaml
g: thongs
f: *cat
```
## Merge copies anchor names
Given a sample.yml file of:
```yaml
a:
c: &cat frog
@ -393,24 +320,18 @@ b:
c:
g: thongs
```
then
```bash
yq eval '.c * .a' sample.yml
```
will output
```yaml
g: thongs
c: &cat frog
```
## Merge with merge anchors
Given a sample.yml file of:
```yaml
foo: &foo
a: foo_a
@ -431,20 +352,17 @@ foobar:
!!merge <<: *foo
thing: foobar_thing
```
then
```bash
yq eval '.foobar * .foobarList' sample.yml
```
will output
```yaml
c: foobarList_c
<<:
!!merge <<:
- *foo
- *bar
thing: foobar_thing
b: foobarList_b
```

31
operators/path.md
View File

@ -5,112 +5,82 @@ The path operator can be used to get the traversal paths of matching nodes in an
You can get the key/index of matching nodes by using the `path` operator to return the path array then piping that through `.[-1]` to get the last element of that array, the key.
## Map path
Given a sample.yml file of:
```yaml
a:
b: cat
```
then
```bash
yq eval '.a.b | path' sample.yml
```
will output
```yaml
- a
- b
```
## Get map key
Given a sample.yml file of:
```yaml
a:
b: cat
```
then
```bash
yq eval '.a.b | path | .[-1]' sample.yml
```
will output
```yaml
b
```
## Array path
Given a sample.yml file of:
```yaml
a:
- cat
- dog
```
then
```bash
yq eval '.a.[] | select(. == "dog") | path' sample.yml
```
will output
```yaml
- a
- 1
```
## Get array index
Given a sample.yml file of:
```yaml
a:
- cat
- dog
```
then
```bash
yq eval '.a.[] | select(. == "dog") | path | .[-1]' sample.yml
```
will output
```yaml
1
```
## Print path and value
Given a sample.yml file of:
```yaml
a:
- cat
- dog
- frog
```
then
```bash
yq eval '.a.[] | select(. == "*og") | [{"path":path, "value":.}]' sample.yml
```
will output
```yaml
- path:
- a
@ -121,3 +91,4 @@ will output
- 2
value: frog
```

13
operators/pipe.md
View File

@ -3,46 +3,35 @@
Pipe the results of an expression into another. Like the bash operator.
## Simple Pipe
Given a sample.yml file of:
```yaml
a:
b: cat
```
then
```bash
yq eval '.a | .b' sample.yml
```
will output
```yaml
cat
```
## Multiple updates
Given a sample.yml file of:
```yaml
a: cow
b: sheep
c: same
```
then
```bash
yq eval '.a = "cat" | .b = "dog"' sample.yml
```
will output
```yaml
a: cat
b: dog
c: same
```

42
operators/recursive-descent-glob.md
View File

@ -1,9 +1,8 @@
# Recursive Descent (Glob)
This operator recursively matches (or globs) all children nodes given of a particular element, including that node itself. This is most often used to apply a filter recursively against all matches. It can be used in either the
This operator recursively matches (or globs) all children nodes given of a particular element, including that node itself. This is most often used to apply a filter recursively against all matches. It can be used in either the
## match values form `..`
This will, like the `jq` equivalent, recursively match all _value_ nodes. Use it to find/manipulate particular values.
For instance to set the `style` of all _value_ nodes in a yaml doc, excluding map keys:
@ -13,7 +12,6 @@ yq eval '.. style= "flow"' file.yaml
```
## match values and map keys form `...`
The also includes map keys in the results set. This is particularly useful in YAML as unlike JSON, map keys can have their own styling, tags and use anchors and aliases.
For instance to set the `style` of all nodes in a yaml doc, including the map keys:
@ -21,34 +19,25 @@ For instance to set the `style` of all nodes in a yaml doc, including the map ke
```bash
yq eval '... style= "flow"' file.yaml
```
## Recurse map (values only)
Given a sample.yml file of:
```yaml
a: frog
```
then
```bash
yq eval '..' sample.yml
```
will output
```yaml
a: frog
frog
```
## Recursively find nodes with keys
Note that this example has wrapped the expression in `[]` to show that there are two matches returned. You do not have to wrap in `[]` in your path expression.
Given a sample.yml file of:
```yaml
a:
name: frog
@ -56,15 +45,11 @@ a:
name: blog
age: 12
```
then
```bash
yq eval '[.. | select(has("name"))]' sample.yml
```
will output
```yaml
- name: frog
b:
@ -75,9 +60,7 @@ will output
```
## Recursively find nodes with values
Given a sample.yml file of:
```yaml
a:
nameA: frog
@ -85,38 +68,28 @@ a:
nameB: frog
age: 12
```
then
```bash
yq eval '.. | select(. == "frog")' sample.yml
```
will output
```yaml
frog
frog
```
## Recurse map (values and keys)
Note that the map key appears in the results
Given a sample.yml file of:
```yaml
a: frog
```
then
```bash
yq eval '...' sample.yml
```
will output
```yaml
a: frog
a
@ -124,23 +97,17 @@ frog
```
## Aliases are not traversed
Given a sample.yml file of:
```yaml
a: &cat
c: frog
b: *cat
```
then
```bash
yq eval '[..]' sample.yml
```
will output
```yaml
- a: &cat
c: frog
@ -152,9 +119,7 @@ will output
```
## Merge docs are not traversed
Given a sample.yml file of:
```yaml
foo: &foo
a: foo_a
@ -175,15 +140,11 @@ foobar:
!!merge <<: *foo
thing: foobar_thing
```
then
```bash
yq eval '.foobar | [..]' sample.yml
```
will output
```yaml
- c: foobar_c
!!merge <<: *foo
@ -192,3 +153,4 @@ will output
- *foo
- foobar_thing
```

24
operators/reduce.md
View File

@ -14,84 +14,64 @@ e.g.
On the LHS we are configuring the collection of items that will be reduced `<exp>` as well as what each element will be called `$<name>`. Note that the array has been splatted into its individual elements.
On the RHS there is `<init>`, the starting value of the accumulator and `<block>`, the expression that will update the accumulator for each element in the collection. Note that within the block expression, `.` will evaluate to the current value of the accumulator.
On the RHS there is `<init>`, the starting value of the accumulator and `<block>`, the expression that will update the accumulator for each element in the collection. Note that within the block expression, `.` will evaluate to the current value of the accumulator.
## yq vs jq syntax
Reduce syntax in `yq` is a little different from `jq` - as `yq` (currently) isn't as sophisticated as `jq` and its only supports infix notation (e.g. a + b, where the operator is in the middle of the two parameters) - where as `jq` uses a mix of infix notation with _prefix_ notation (e.g. `reduce a b` is like writing `+ a b`).
To that end, the reduce operator is called `ireduce` for backwards compatability if a `jq` like prefix version of `reduce` is ever added.
## Sum numbers
Given a sample.yml file of:
```yaml
- 10
- 2
- 5
- 3
```
then
```bash
yq eval '.[] as $item ireduce (0; . + $item)' sample.yml
```
will output
```yaml
20
```
## Merge all yaml files together
Given a sample.yml file of:
```yaml
a: cat
```
And another sample another.yml file of:
```yaml
b: dog
```
then
```bash
yq eval-all '. as $item ireduce ({}; . * $item )' sample.yml another.yml
```
will output
```yaml
a: cat
b: dog
```
## Convert an array to an object
Given a sample.yml file of:
```yaml
- name: Cathy
has: apples
- name: Bob
has: bananas
```
then
```bash
yq eval '.[] as $item ireduce ({}; .[$item | .name] = ($item | .has) )' sample.yml
```
will output
```yaml
Cathy: apples
Bob: bananas
```

13
operators/select.md
View File

@ -3,50 +3,39 @@
Select is used to filter arrays and maps by a boolean expression.
## Select elements from array
Given a sample.yml file of:
```yaml
- cat
- goat
- dog
```
then
```bash
yq eval '.[] | select(. == "*at")' sample.yml
```
will output
```yaml
cat
goat
```
## Select and update matching values in map
Given a sample.yml file of:
```yaml
a:
things: cat
bob: goat
horse: dog
```
then
```bash
yq eval '(.a.[] | select(. == "*at")) |= "rabbit"' sample.yml
```
will output
```yaml
a:
things: rabbit
bob: rabbit
horse: dog
```

13
operators/sort-keys.md
View File

@ -11,23 +11,17 @@ diff file1.yml file2.yml
```
## Sort keys of map
Given a sample.yml file of:
```yaml
c: frog
a: blah
b: bing
```
then
```bash
yq eval 'sortKeys(.)' sample.yml
```
will output
```yaml
a: blah
b: bing
@ -35,11 +29,9 @@ c: frog
```
## Sort keys recursively
Note the array elements are left unsorted, but maps inside arrays are sorted
Given a sample.yml file of:
```yaml
bParent:
c: dog
@ -55,15 +47,11 @@ aParent:
- b: ew
a: apple
```
then
```bash
yq eval 'sortKeys(..)' sample.yml
```
will output
```yaml
aParent:
x:
@ -79,3 +67,4 @@ bParent:
- 2
c: dog
```

12
operators/split-into-documents.md
View File

@ -3,37 +3,29 @@
This operator splits all matches into separate documents
## Split empty
Running
```bash
yq eval --null-input 'splitDoc'
```
will output
```yaml
```
## Split array
Given a sample.yml file of:
```yaml
- a: cat
- b: dog
```
then
```bash
yq eval '.[] | splitDoc' sample.yml
```
will output
```yaml
a: cat
---
b: dog
```

120
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View File

@ -1,13 +1,10 @@
# String Operators
## String Operators
## RegEx
This uses golangs native regex functions under the hood - See https://github.com/google/re2/wiki/Syntax for the supported syntax.
### RegEx
This uses golangs native regex functions under the hood - See [https://github.com/google/re2/wiki/Syntax](https://github.com/google/re2/wiki/Syntax) for the supported syntax.
## String blocks, bash and newlines
Bash is notorious for chomping on precious trailing newline characters, making it tricky to set strings with newlines properly. In particular, the `$( exp )` _will trim trailing newlines_.
For instance to get this yaml:
@ -25,7 +22,6 @@ a: cat
```
However, using printf works:
```
printf -v m "cat\n" ; m="$m" yq e -n '.a = strenv(m)'
a: |
@ -33,7 +29,6 @@ a: |
```
As well as having multiline expressions:
```
m="cat
" yq e -n '.a = strenv(m)'
@ -48,10 +43,8 @@ IFS= read -rd '' output < <(cat my_file)
output=$output ./yq e '.data.values = strenv(output)' first.yml
```
### Join strings
## Join strings
Given a sample.yml file of:
```yaml
- cat
- meow
@ -59,35 +52,25 @@ Given a sample.yml file of:
- null
- true
```
then
```bash
yq eval 'join("; ")' sample.yml
```
will output
```yaml
cat; meow; 1; ; true
```
### Match string
## Match string
Given a sample.yml file of:
```yaml
foo bar foo
```
then
```bash
yq eval 'match("foo")' sample.yml
```
will output
```yaml
string: foo
offset: 0
@ -95,22 +78,16 @@ length: 3
captures: []
```
### Match string, case insensitive
## Match string, case insensitive
Given a sample.yml file of:
```yaml
foo bar FOO
```
then
```bash
yq eval '[match("(?i)foo"; "g")]' sample.yml
```
will output
```yaml
- string: foo
offset: 0
@ -122,22 +99,16 @@ will output
captures: []
```
### Match with capture groups
## Match with capture groups
Given a sample.yml file of:
```yaml
abc abc
```
then
```bash
yq eval '[match("(abc)+"; "g")]' sample.yml
```
will output
```yaml
- string: abc
offset: 0
@ -155,22 +126,16 @@ will output
length: 3
```
### Match with named capture groups
## Match with named capture groups
Given a sample.yml file of:
```yaml
foo bar foo foo foo
```
then
```bash
yq eval '[match("foo (?P<bar123>bar)? foo"; "g")]' sample.yml
```
will output
```yaml
- string: foo bar foo
offset: 0
@ -190,43 +155,31 @@ will output
name: bar123
```
### Capture named groups into a map
## Capture named groups into a map
Given a sample.yml file of:
```yaml
xyzzy-14
```
then
```bash
yq eval 'capture("(?P<a>[a-z]+)-(?P<n>[0-9]+)")' sample.yml
```
will output
```yaml
a: xyzzy
n: "14"
```
### Match without global flag
## Match without global flag
Given a sample.yml file of:
```yaml
cat cat
```
then
```bash
yq eval 'match("cat")' sample.yml
```
will output
```yaml
string: cat
offset: 0
@ -234,22 +187,16 @@ length: 3
captures: []
```
### Match with global flag
## Match with global flag
Given a sample.yml file of:
```yaml
cat cat
```
then
```bash
yq eval '[match("cat"; "g")]' sample.yml
```
will output
```yaml
- string: cat
offset: 0
@ -261,92 +208,70 @@ will output
captures: []
```
### Test using regex
## Test using regex
Like jq'q equivalant, this works like match but only returns true/false instead of full match details
Given a sample.yml file of:
```yaml
- cat
- dog
```
then
```bash
yq eval '.[] | test("at")' sample.yml
```
will output
```yaml
true
false
```
### Substitute / Replace string
This uses golang regex, described [here](https://github.com/google/re2/wiki/Syntax) Note the use of `|=` to run in context of the current string value.
## Substitute / Replace string
This uses golang regex, described [here](https://github.com/google/re2/wiki/Syntax)
Note the use of `|=` to run in context of the current string value.
Given a sample.yml file of:
```yaml
a: dogs are great
```
then
```bash
yq eval '.a |= sub("dogs", "cats")' sample.yml
```
will output
```yaml
a: cats are great
```
### Substitute / Replace string with regex
This uses golang regex, described [here](https://github.com/google/re2/wiki/Syntax) Note the use of `|=` to run in context of the current string value.
## Substitute / Replace string with regex
This uses golang regex, described [here](https://github.com/google/re2/wiki/Syntax)
Note the use of `|=` to run in context of the current string value.
Given a sample.yml file of:
```yaml
a: cat
b: heat
```
then
```bash
yq eval '.[] |= sub("(a)", "${1}r")' sample.yml
```
will output
```yaml
a: cart
b: heart
```
### Split strings
## Split strings
Given a sample.yml file of:
```yaml
cat; meow; 1; ; true
```
then
```bash
yq eval 'split("; ")' sample.yml
```
will output
```yaml
- cat
- meow
@ -355,22 +280,17 @@ will output
- "true"
```
### Split strings one match
## Split strings one match
Given a sample.yml file of:
```yaml
word
```
then
```bash
yq eval 'split("; ")' sample.yml
```
will output
```yaml
- word
```

73
operators/style.md
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@ -3,23 +3,17 @@
The style operator can be used to get or set the style of nodes (e.g. string style, yaml style)
## Update and set style of a particular node (simple)
Given a sample.yml file of:
```yaml
a:
b: thing
c: something
```
then
```bash
yq eval '.a.b = "new" | .a.b style="double"' sample.yml
```
will output
```yaml
a:
b: "new"
@ -27,23 +21,17 @@ a:
```
## Update and set style of a particular node using path variables
Given a sample.yml file of:
```yaml
a:
b: thing
c: something
```
then
```bash
yq eval 'with(.a.b ; . = "new" | . style="double")' sample.yml
```
will output
```yaml
a:
b: "new"
@ -51,24 +39,18 @@ a:
```
## Set tagged style
Given a sample.yml file of:
```yaml
a: cat
b: 5
c: 3.2
e: true
```
then
```bash
yq eval '.. style="tagged"' sample.yml
```
will output
```yaml
!!map
a: !!str cat
@ -78,24 +60,18 @@ e: !!bool true
```
## Set double quote style
Given a sample.yml file of:
```yaml
a: cat
b: 5
c: 3.2
e: true
```
then
```bash
yq eval '.. style="double"' sample.yml
```
will output
```yaml
a: "cat"
b: "5"
@ -104,24 +80,18 @@ e: "true"
```
## Set double quote style on map keys too
Given a sample.yml file of:
```yaml
a: cat
b: 5
c: 3.2
e: true
```
then
```bash
yq eval '... style="double"' sample.yml
```
will output
```yaml
"a": "cat"
"b": "5"
@ -130,24 +100,18 @@ will output
```
## Set single quote style
Given a sample.yml file of:
```yaml
a: cat
b: 5
c: 3.2
e: true
```
then
```bash
yq eval '.. style="single"' sample.yml
```
will output
```yaml
a: 'cat'
b: '5'
@ -156,24 +120,18 @@ e: 'true'
```
## Set literal quote style
Given a sample.yml file of:
```yaml
a: cat
b: 5
c: 3.2
e: true
```
then
```bash
yq eval '.. style="literal"' sample.yml
```
will output
```yaml
a: |-
cat
@ -186,24 +144,18 @@ e: |-
```
## Set folded quote style
Given a sample.yml file of:
```yaml
a: cat
b: 5
c: 3.2
e: true
```
then
```bash
yq eval '.. style="folded"' sample.yml
```
will output
```yaml
a: >-
cat
@ -216,49 +168,37 @@ e: >-
```
## Set flow quote style
Given a sample.yml file of:
```yaml
a: cat
b: 5
c: 3.2
e: true
```
then
```bash
yq eval '.. style="flow"' sample.yml
```
will output
```yaml
{a: cat, b: 5, c: 3.2, e: true}
```
## Reset style - or pretty print
Set empty (default) quote style, note the usage of `...` to match keys too. Note that there is a `--prettyPrint/-P` short flag for this.
Given a sample.yml file of:
```yaml
a: cat
"b": 5
'c': 3.2
"e": true
```
then
```bash
yq eval '... style=""' sample.yml
```
will output
```yaml
a: cat
b: 5
@ -267,45 +207,34 @@ e: true
```
## Set style relatively with assign-update
Given a sample.yml file of:
```yaml
a: single
b: double
```
then
```bash
yq eval '.[] style |= .' sample.yml
```
will output
```yaml
a: 'single'
b: "double"
```
## Read style
Given a sample.yml file of:
```yaml
{a: "cat", b: 'thing'}
```
then
```bash
yq eval '.. | style' sample.yml
```
will output
```yaml
flow
double
single
```

41
operators/subtract.md
View File

@ -1,148 +1,113 @@
# Subtract
You can use subtract to subtract numbers, as well as removing elements from an array.
## Array subtraction
Running
```bash
yq eval --null-input '[1,2] - [2,3]'
```
will output
```yaml
- 1
```
## Array subtraction with nested array
Running
```bash
yq eval --null-input '[[1], 1, 2] - [[1], 3]'
```
will output
```yaml
- 1
- 2
```
## Array subtraction with nested object
Note that order of the keys does not matter
Given a sample.yml file of:
```yaml
- a: b
c: d
- a: b
```
then
```bash
yq eval '. - [{"c": "d", "a": "b"}]' sample.yml
```
will output
```yaml
- a: b
```
## Number subtraction - float
If the lhs or rhs are floats then the expression will be calculated with floats.
Given a sample.yml file of:
```yaml
a: 3
b: 4.5
```
then
```bash
yq eval '.a = .a - .b' sample.yml
```
will output
```yaml
a: -1.5
b: 4.5
```
## Number subtraction - float
If the lhs or rhs are floats then the expression will be calculated with floats.
Given a sample.yml file of:
```yaml
a: 3
b: 4.5
```
then
```bash
yq eval '.a = .a - .b' sample.yml
```
will output
```yaml
a: -1.5
b: 4.5
```
## Number subtraction - int
If both the lhs and rhs are ints then the expression will be calculated with ints.
Given a sample.yml file of:
```yaml
a: 3
b: 4
```
then
```bash
yq eval '.a = .a - .b' sample.yml
```
will output
```yaml
a: -1
b: 4
```
## Decrement numbers
Given a sample.yml file of:
```yaml
a: 3
b: 5
```
then
```bash
yq eval '.[] -= 1' sample.yml
```
will output
```yaml
a: 2
b: 4
```

19
operators/tag.md
View File

@ -3,9 +3,7 @@
The tag operator can be used to get or set the tag of nodes (e.g. `!!str`, `!!int`, `!!bool`).
## Get tag
Given a sample.yml file of:
```yaml
a: cat
b: 5
@ -13,15 +11,11 @@ c: 3.2
e: true
f: []
```
then
```bash
yq eval '.. | tag' sample.yml
```
will output
```yaml
!!map
!!str
@ -32,47 +26,36 @@ will output
```
## Set custom tag
Given a sample.yml file of:
```yaml
a: str
```
then
```bash
yq eval '.a tag = "!!mikefarah"' sample.yml
```
will output
```yaml
a: !!mikefarah str
```
## Find numbers and convert them to strings
Given a sample.yml file of:
```yaml
a: cat
b: 5
c: 3.2
e: true
```
then
```bash
yq eval '(.. | select(tag == "!!int")) tag= "!!str"' sample.yml
```
will output
```yaml
a: cat
b: "5"
c: 3.2
e: true
```

147
operators/traverse-read.md
View File

@ -3,381 +3,277 @@
This is the simplest (and perhaps most used) operator, it is used to navigate deeply into yaml structures.
## Simple map navigation
Given a sample.yml file of:
```yaml
a:
b: apple
```
then
```bash
yq eval '.a' sample.yml
```
will output
```yaml
b: apple
```
## Splat
Often used to pipe children into other operators
Given a sample.yml file of:
```yaml
- b: apple
- c: banana
```
then
```bash
yq eval '.[]' sample.yml
```
will output
```yaml
b: apple
c: banana
```
## Optional Splat
Just like splat, but won't error if you run it against scalars
Given a sample.yml file of:
```yaml
cat
```
then
```bash
yq eval '.[]' sample.yml
```
will output
```yaml
```
## Special characters
Use quotes with brackets around path elements with special characters
Given a sample.yml file of:
```yaml
"{}": frog
```
then
```bash
yq eval '.["{}"]' sample.yml
```
will output
```yaml
frog
```
## Nested special characters
Given a sample.yml file of:
```yaml
a:
"key.withdots":
"another.key": apple
```
then
```bash
yq eval '.a["key.withdots"]["another.key"]' sample.yml
```
will output
```yaml
apple
```
## Keys with spaces
Use quotes with brackets around path elements with special characters
Given a sample.yml file of:
```yaml
"red rabbit": frog
```
then
```bash
yq eval '.["red rabbit"]' sample.yml
```
will output
```yaml
frog
```
## Dynamic keys
Expressions within \[] can be used to dynamically lookup / calculate keys
Expressions within [] can be used to dynamically lookup / calculate keys
Given a sample.yml file of:
```yaml
b: apple
apple: crispy yum
banana: soft yum
```
then
```bash
yq eval '.[.b]' sample.yml
```
will output
```yaml
crispy yum
```
## Children don't exist
Nodes are added dynamically while traversing
Given a sample.yml file of:
```yaml
c: banana
```
then
```bash
yq eval '.a.b' sample.yml
```
will output
```yaml
null
```
## Optional identifier
Like jq, does not output an error when the yaml is not an array or object as expected
Given a sample.yml file of:
```yaml
- 1
- 2
- 3
```
then
```bash
yq eval '.a?' sample.yml
```
will output
```yaml
```
## Wildcard matching
Given a sample.yml file of:
```yaml
a:
cat: apple
mad: things
```
then
```bash
yq eval '.a."*a*"' sample.yml
```
will output
```yaml
apple
things
```
## Aliases
Given a sample.yml file of:
```yaml
a: &cat
c: frog
b: *cat
```
then
```bash
yq eval '.b' sample.yml
```
will output
```yaml
*cat
```
## Traversing aliases with splat
Given a sample.yml file of:
```yaml
a: &cat
c: frog
b: *cat
```
then
```bash
yq eval '.b[]' sample.yml
```
will output
```yaml
frog
```
## Traversing aliases explicitly
Given a sample.yml file of:
```yaml
a: &cat
c: frog
b: *cat
```
then
```bash
yq eval '.b.c' sample.yml
```
will output
```yaml
frog
```
## Traversing arrays by index
Given a sample.yml file of:
```yaml
- 1
- 2
- 3
```
then
```bash
yq eval '.[0]' sample.yml
```
will output
```yaml
1
```
## Traversing nested arrays by index
Given a sample.yml file of:
```yaml
[[], [cat]]
```
then
```bash
yq eval '.[1][0]' sample.yml
```
will output
```yaml
cat
```
## Maps with numeric keys
Given a sample.yml file of:
```yaml
2: cat
```
then
```bash
yq eval '.[2]' sample.yml
```
will output
```yaml
cat
```
## Maps with non existing numeric keys
Given a sample.yml file of:
```yaml
a: b
```
then
```bash
yq eval '.[0]' sample.yml
```
will output
```yaml
null
```
## Traversing merge anchors
Given a sample.yml file of:
```yaml
foo: &foo
a: foo_a
@ -398,23 +294,17 @@ foobar:
!!merge <<: *foo
thing: foobar_thing
```
then
```bash
yq eval '.foobar.a' sample.yml
```
will output
```yaml
foo_a
```
## Traversing merge anchors with override
Given a sample.yml file of:
```yaml
foo: &foo
a: foo_a
@ -435,23 +325,17 @@ foobar:
!!merge <<: *foo
thing: foobar_thing
```
then
```bash
yq eval '.foobar.c' sample.yml
```
will output
```yaml
foo_c
```
## Traversing merge anchors with local override
Given a sample.yml file of:
```yaml
foo: &foo
a: foo_a
@ -472,23 +356,17 @@ foobar:
!!merge <<: *foo
thing: foobar_thing
```
then
```bash
yq eval '.foobar.thing' sample.yml
```
will output
```yaml
foobar_thing
```
## Splatting merge anchors
Given a sample.yml file of:
```yaml
foo: &foo
a: foo_a
@ -509,15 +387,11 @@ foobar:
!!merge <<: *foo
thing: foobar_thing
```
then
```bash
yq eval '.foobar[]' sample.yml
```
will output
```yaml
foo_c
foo_a
@ -525,11 +399,9 @@ foobar_thing
```
## Traversing merge anchor lists
Note that the later merge anchors override previous
Given a sample.yml file of:
```yaml
foo: &foo
a: foo_a
@ -550,23 +422,17 @@ foobar:
!!merge <<: *foo
thing: foobar_thing
```
then
```bash
yq eval '.foobarList.thing' sample.yml
```
will output
```yaml
bar_thing
```
## Splatting merge anchor lists
Given a sample.yml file of:
```yaml
foo: &foo
a: foo_a
@ -587,15 +453,11 @@ foobar:
!!merge <<: *foo
thing: foobar_thing
```
then
```bash
yq eval '.foobarList[]' sample.yml
```
will output
```yaml
bar_b
foo_a
@ -604,25 +466,20 @@ foobarList_c
```
## Select multiple indices
Given a sample.yml file of:
```yaml
a:
- a
- b
- c
```
then
```bash
yq eval '.a[0, 2]' sample.yml
```
will output
```yaml
a
c
```

11
operators/union.md
View File

@ -3,15 +3,11 @@
This operator is used to combine different results together.
## Combine scalars
Running
```bash
yq eval --null-input '1, true, "cat"'
```
will output
```yaml
1
true
@ -19,24 +15,19 @@ cat
```
## Combine selected paths
Given a sample.yml file of:
```yaml
a: fieldA
b: fieldB
c: fieldC
```
then
```bash
yq eval '.a, .c' sample.yml
```
will output
```yaml
fieldA
fieldC
```

25
operators/unique.md
View File

@ -3,24 +3,18 @@
This is used to filter out duplicated items in an array.
## Unique array of scalars (string/numbers)
Given a sample.yml file of:
```yaml
- 1
- 2
- 3
- 2
```
then
```bash
yq eval 'unique' sample.yml
```
will output
```yaml
- 1
- 2
@ -28,60 +22,46 @@ will output
```
## Unique nulls
Unique works on the node value, so it considers different representations of nulls to be different
Given a sample.yml file of:
```yaml
- ~
- null
- ~
- null
```
then
```bash
yq eval 'unique' sample.yml
```
will output
```yaml
- ~
- null
```
## Unique all nulls
Run against the node tag to unique all the nulls
Given a sample.yml file of:
```yaml
- ~
- null
- ~
- null
```
then
```bash
yq eval 'unique_by(tag)' sample.yml
```
will output
```yaml
- ~
```
## Unique array object fields
Given a sample.yml file of:
```yaml
- name: harry
pet: cat
@ -90,18 +70,15 @@ Given a sample.yml file of:
- name: harry
pet: dog
```
then
```bash
yq eval 'unique_by(.name)' sample.yml
```
will output
```yaml
- name: harry
pet: cat
- name: billy
pet: dog
```

31
operators/variable-operators.md
View File

@ -5,53 +5,39 @@ Like the `jq` equivalents, variables are sometimes required for the more complex
Note that there is also an additional `ref` operator that holds a reference (instead of a copy) of the path, allowing you to make multiple changes to the same path.
## Single value variable
Given a sample.yml file of:
```yaml
a: cat
```
then
```bash
yq eval '.a as $foo | $foo' sample.yml
```
will output
```yaml
cat
```
## Multi value variable
Given a sample.yml file of:
```yaml
- cat
- dog
```
then
```bash
yq eval '.[] as $foo | $foo' sample.yml
```
will output
```yaml
cat
dog
```
## Using variables as a lookup
Example taken from [jq](https://stedolan.github.io/jq/manual/#Variable/SymbolicBindingOperator:...as$identifier|...)
Given a sample.yml file of:
```yaml
"posts":
- "title": Frist psot
@ -62,15 +48,11 @@ Given a sample.yml file of:
"anon": Anonymous Coward
"person1": Person McPherson
```
then
```bash
yq eval '.realnames as $names | .posts[] | {"title":.title, "author": $names[.author]}' sample.yml
```
will output
```yaml
title: Frist psot
author: Anonymous Coward
@ -79,49 +61,38 @@ author: Person McPherson
```
## Using variables to swap values
Given a sample.yml file of:
```yaml
a: a_value
b: b_value
```
then
```bash
yq eval '.a as $x | .b as $y | .b = $x | .a = $y' sample.yml
```
will output
```yaml
a: b_value
b: a_value
```
## Use ref to reference a path repeatedly
Note: You may find the `with` operator more useful.
Given a sample.yml file of:
```yaml
a:
b: thing
c: something
```
then
```bash
yq eval '.a.b ref $x | $x = "new" | $x style="double"' sample.yml
```
will output
```yaml
a:
b: "new"
c: something
```

25
operators/with.md
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@ -3,23 +3,17 @@
Use the `with` operator to conveniently make multiple updates to a deeply nested path, or to update array elements relatively to each other. The first argument expression sets the root context, and the second expression runs against that root context.
## Update and style
Given a sample.yml file of:
```yaml
a:
deeply:
nested: value
```
then
```bash
yq eval 'with(.a.deeply.nested ; . = "newValue" | . style="single")' sample.yml
yq eval 'with(.a.deeply.nested; . = "newValue" | . style="single")' sample.yml
```
will output
```yaml
a:
deeply:
@ -27,24 +21,18 @@ a:
```
## Update multiple deeply nested properties
Given a sample.yml file of:
```yaml
a:
deeply:
nested: value
other: thing
```
then
```bash
yq eval 'with(.a.deeply ; .nested = "newValue" | .other= "newThing")' sample.yml
yq eval 'with(.a.deeply; .nested = "newValue" | .other= "newThing")' sample.yml
```
will output
```yaml
a:
deeply:
@ -53,25 +41,19 @@ a:
```
## Update array elements relatively
The second expression runs with each element of the array as it's contextual root. This allows you to make updates relative to the element.
Given a sample.yml file of:
```yaml
myArray:
- a: apple
- a: banana
```
then
```bash
yq eval 'with(.myArray[] ; .b = .a + " yum")' sample.yml
yq eval 'with(.myArray[]; .b = .a + " yum")' sample.yml
```
will output
```yaml
myArray:
- a: apple
@ -79,3 +61,4 @@ myArray:
- a: banana
b: banana yum
```