YAML configuration files¶
This page has information on features of YAML which will be useful while writing the configuration files for DataOS Resources
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Declare multiple entities and Resource-instances in a single YAML file. To do this, use three dashes
---
to separate the two entities. For example, we can create a Depot while using the reference of a Secret in the same config file.version: v1 name: s3-pos-rw type: secret secret: type: key-value-properties acl: rw data: accesskeyid: secretkey: awsaccesskeyid: awssecretaccesskey: --- version: v1 name: type: depot tags: layer: user depot: type: S3 description: spec: bucket: relativePath: external: true # using the 'Secret' created & stored previously dataosSecrets: - name: s3-pos-rw workspace: public keys: - public_s3-pos-rw
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YAML supports mapping, which are unordered collections of key-value pairs. Mappings are represented using a colon followed by whitespace.
In the above example,
person
is a mapping with keysname
&age
, and their corresponding values. -
YAML supports lists & arrays using the dash
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followed by a space. The list, in turn can have mappings or objects or simple key-value pairs.fruits: - apple: no - banana: price: 24 rotten: yes - orange: dozen --- vegetables: - donoteat - tastesbad
In the above example,
fruits
is a list of objects, whilevegetables
is an array. Mappings & arrays can also be declared using the flow style syntax. -
The objects at the same hierarchical level are interchangeable in order. For example, a new Secret is created using the following config file:
version: v1 name: s3-pos-rw type: secret secret: type: key-value-properties acl: rw data: accesskeyid: ${{access key id}} secretkey: ${{secret key}} awsaccesskeyid: ${{aws access key id}} awssecretaccesskey: ${{aws secret access key}}
The same Secret can be created by using applying this config file:
version: v1 type: secret name: s3-pos-rw secret: acl: rw type: key-value-properties data: accesskeyid: ${{access key id}} secretkey: ${{secret key}} awsaccesskeyid: ${{aws access key id}} awssecretaccesskey: ${{aws secret access key}}
Note that the order of objects is different in the two cases. Yet, both the config files are parsed in exactly the same manner, and will create the same Secret.
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The number of spaces used for indentation at the same hierarchical level of the config file must be same. This is specifically important when creating a nested list of objects.
version: v1 name: description: This is a sample template workflow: title: schedule: cron: concurrencyPolicy: dag: # Job 1 (There should be at least one job within a DAG) - name: title: spec: stack: ${{stack1-version}} compute: # Job 2 - name: title: spec: stack: ${{stack2-version}} compute: dependencies: -
The attributes,
title
,schedule
anddag
are at the same hierarchical level, hence each has the same indentation of two spaces. While the nested objects within these fields, like thecron
, list ofjobs
andspec
have indentations of four spaces. -
The pipe character is used to represent multiline string. This is useful when dealing with complex or larger data. For example,