Inject step and stage in existing Template
Currently this feature is behind the feature flag PIE_FLEXIBLE_TEMPLATES. Please contact Harness support to enable this feature.
Inject blocks provide a way to customize pipelines without affecting the main template.
Steps and stages included in the inject block will behave the same as normal steps and stages in the pipeline.
Inject block is only supported for CD, Custom and Approval Stages.
Pros of Using Inject blocks in a template
- Only the Template Editor has the flexibility to allow additional steps or stages at any given point where they want.(At beginning of all steps/stage or at the end of all steps/stages or in between the steps/stages)
- The YAML would be very simple and incline with existing harness steps/stages YAML. Here the Inject is as simply a new type of step which starts with the key
inject.
Now, let's dive into who can add inject block in the pipeline and stage template and how other users can utilise it in their pipelines.
Inject stage block in Pipeline Template
Template editors will be able to add inject stage block in the pipeline template at any position between a stage.
Sample YAML of a pipeline template with inject stage block will look like:
template:
name: pipeline_inject_template
identifier: pipeline_inject_template
versionLabel: v2
type: Pipeline
projectIdentifier: Inject_block
orgIdentifier: default
tags: {}
spec:
stages:
- stage:
name: cust_1
identifier: cust_1
description: ""
type: Custom
spec:
execution:
steps:
- step:
type: ShellScript
name: ShellScript_1
identifier: ShellScript_1
spec:
shell: Bash
executionTarget: {}
source:
type: Inline
spec:
script: echo hello
environmentVariables: []
outputVariables: []
timeout: 10m
- inject:
identifier: injectStages1
name: injectStages1
stages: <+input>
tags: {}
- stage:
name: cust_2
identifier: cust_2
description: ""
type: Custom
spec:
execution:
steps:
- step:
type: ShellScript
name: ShellScript_1
identifier: ShellScript_1
spec:
shell: Bash
executionTarget: {}
source:
type: Inline
spec:
script: echo hello_2
environmentVariables: []
outputVariables: []
timeout: 10m
- inject:
identifier: injectStages2
name: injectStages1
stages: <+input>
tags: {}
Inject step block in Stage Template
Similarly, as a Template Editor you can add a inject step block in the stage template at any position between a step.
Sample YAML of a stage template with an inject step block will look like:-
template:
name: stage_inject_template
identifier: stage_inject_template
versionLabel: v2
type: Stage
projectIdentifier: Inject_block
orgIdentifier: default
tags: {}
spec:
type: Custom
spec:
execution:
steps:
- step:
type: ShellScript
name: ShellScript_1
identifier: ShellScript_1
spec:
shell: Bash
executionTarget: {}
source:
type: Inline
spec:
script: echo hello
environmentVariables: []
outputVariables: []
timeout: 10m
- inject:
identifier: injectSteps1
name: injectSteps1
steps: <+input>
- step:
type: ShellScript
name: ShellScript_2
identifier: ShellScript_2
spec:
shell: Bash
executionTarget: {}
source:
type: Inline
spec:
script: echo hello_2
environmentVariables: []
outputVariables: []
timeout: 10m
- inject:
identifier: injectSteps2
name: injectSteps2
steps: <+input>
This allows you, as the template editor, to maintain control over the template, ensuring its integrity is preserved.
Now, if you use a template with a inject step/stage block in a pipeline, suppose you are using a pipeline template while creating a pipeline in a pipeline studio those inject stages will come under templateInputs.
Sample YAML:
pipeline:
name: pipeline_inject_sample
identifier: pipeline_inject_sample
tags: {}
template:
templateRef: pipeline_inject_template
versionLabel: v2
templateInputs:
stages:
- inject:
identifier: injectStages1
stages: <+input>
- inject:
identifier: injectStages2
stages: <+input>
projectIdentifier: Inject_block
orgIdentifier: default
In the above YAML as you can see, we have used pipeline template pipeline_inject_template which are having two inject blocks and those inject blocks are under templateInputs.
Template user can add additional step and stage wherever an inject block has been defined. The inject block support inclusion of stages and steps along with runtime inputs, failure strategies, and conditional execution.
Consider a YAML using stage template in a pipeline with an inject step block:-
pipeline:
name: pipeline_sample
identifier: pipeline_sample
projectIdentifier: Krishika_test_autocreation
orgIdentifier: default
tags: {}
stages:
- stage:
name: stage_1
identifier: stage_1
tags: {}
template:
templateRef: stage_inject_template
versionLabel: v2
templateInputs:
type: Custom
spec:
execution:
steps:
- inject:
identifier: injectSteps1
steps:
- parallel:
- step:
identifier: shell1
type: ShellScript
name: shell1
spec:
shell: Bash
executionTarget: {}
source:
type: Inline
spec:
script: echo hello_3
environmentVariables: []
outputVariables: []
timeout: 10m
failureStrategies:
- onFailure:
errors:
- AllErrors
action:
type: Ignore
- inject:
identifier: injectSteps2
steps: <+input>
In this, under the first inject block we have added one Shell Script step. Now, when we run the pipeline the execution will look like :-
If no actions are provided in the inject block the pipeline will proceed without any additonal steps and stages.
For example, in the below yaml, we have used this stage template in the pipeline with 2 inject blocks and we have not added any additional steps in it:-
pipeline:
name: pipeline_inject_sample
identifier: pipeline_inject_sample
projectIdentifier: Krishika_test_autocreation
orgIdentifier: default
tags: {}
stages:
- stage:
name: stage_1
identifier: stagd_1
tags: {}
template:
templateRef: stage_inject_template
versionLabel: v2
templateInputs:
type: Custom
spec:
execution:
steps:
- inject:
identifier: injectSteps1
steps: <+input>
- inject:
identifier: injectSteps2
steps: <+input>
Now when we will run the pipeline the execution will look like:-
If you will check the compiled YAML it will show the steps input as empty and thus will not fail the pipeline as well with a null error.
- Inject block can not be output of any step, it has to be provided.
- Nested inject blocks are not allowed.
Expressions
If we intend to utilize expressions for the properties within the inject, it will be necessary to specify the complete path for each one.
Example: <+execution.steps.inject1.steps.ShellScript_1.description>
RBAC required
- Users must possess the Template Create/Edit Permission in order to insert an inject block into the template at any desired location.
- In order to provide the steps/stages input to inject block when specifying runtime inputs in the pipeline, users must have Pipeline Create/Edit Permission. Otherwise, if they intend to provide input values in the parent template, Template Create/Edit Permission will be required.