yq/mkdocs/read.md
2018-07-10 21:24:13 +10:00

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Markdown

```
yq r <yaml_file|json_file> <path>
```
{!snippets/works_with_json.md!}
### Basic
Given a sample.yaml file of:
```yaml
b:
c: 2
```
then
```bash
yq r sample.yaml b.c
```
will output the value of '2'.
### From Stdin
Given a sample.yaml file of:
```bash
cat sample.yaml | yq r - b.c
```
will output the value of '2'.
### Splat
Given a sample.yaml file of:
```yaml
---
bob:
item1:
cats: bananas
item2:
cats: apples
```
then
```bash
yq r sample.yaml bob.*.cats
```
will output
```yaml
- bananas
- apples
```
### Multiple Documents - specify a single document
Given a sample.yaml file of:
```yaml
something: else
---
b:
c: 2
```
then
```bash
yq r -d1 sample.yaml b.c
```
will output the value of '2'.
### Multiple Documents - read all documents
Reading all documents will return the result as an array. This can be converted to json using the '-j' flag if desired.
Given a sample.yaml file of:
```yaml
name: Fred
age: 22
---
name: Stella
age: 23
---
name: Android
age: 232
```
then
```bash
yq r -d'*' sample.yaml name
```
will output:
```
- Fred
- Stella
- Android
```
### Arrays
You can give an index to access a specific element:
e.g.: given a sample file of
```yaml
b:
e:
- name: fred
value: 3
- name: sam
value: 4
```
then
```
yq r sample.yaml 'b.e[1].name'
```
will output 'sam'
Note that the path is in quotes to avoid the square brackets being interpreted by your shell.
### Array Splat
e.g.: given a sample file of
```yaml
b:
e:
- name: fred
value: 3
- name: sam
value: 4
```
then
```
yq r sample.yaml 'b.e[*].name'
```
will output:
```
- fred
- sam
```
Note that the path is in quotes to avoid the square brackets being interpreted by your shell.
{!snippets/keys_with_dots.md!}