[jsonmp-k8]

Problem

Two more items from #13966, following #15268 (circular references):

1. root is not reserved. The compiler visits the pipeline's root DAG under the name root (RootComponentName), but nothing stops a user component from having the same name (TODO(Bobgy): reserve root as a keyword). Referencing such a component is reported as a circular reference, root -> root, which points at the wrong problem. An unreferenced root component is accepted silently.
2. Lookup errors don't say where the reference is. When a task references an undefined component, or a component names an undefined executor, the error only names the component being processed: error processing component name="comp-a": cannot find component ref name="comp-missing". The task holding the broken reference isn't mentioned.

The remaining #13966 item, removing the JSON round trip in GetPipelineSpec/GetDeploymentConfig, is not included.

Part of #13966

Description of your changes:

• Accept rejects a pipeline spec whose components contain root: component name "root" is reserved for the pipeline's root DAG. Rename the component. The SDK names components comp-<name>, so compiled SDK pipelines are unaffected. All 315 compiler golden specs pass unchanged.
• A missing component ref now reports the task: task "task-comp-missing" references component "comp-missing", which is not defined in the pipeline spec's components. Add the component or fix the task's componentRef.
• A missing executor now reports the task and its enclosing component: executor(label="exec-missing") not found in deployment config, used by task "task-comp-leaf" in component "comp-a". Add the executor to deploymentSpec.executors or fix the component's executorLabel. If the root itself is an executor component (a malformed spec with no enclosing task), the usage clause is omitted instead of indexing past the path.

Reproducer

A spec with root.dag.tasks.task-root.componentRef.name: root and a components.root container component:

• Before: circular component reference detected: root -> root. Remove the task that references an enclosing component
• After: component name "root" is reserved for the pipeline's root DAG. Rename the component

flowchart LR
  subgraph Before
    B_spec["components: {root: ...}"] --> B_dfs["DFS visits root DAG as 'root'"]
    B_dfs --> B_err["'circular reference: root -> root'<br/>or accepted if unreferenced"]
  end
  subgraph After
    A_spec["components: {root: ...}"] --> A_check["Accept checks reserved name"]
    A_check --> A_err["'component name &quot;root&quot; is reserved'"]
  end

Loading

Regression tests

In backend/src/v2/compiler/visitor_test.go:

• TestAccept_RejectsComponentNamedRoot: referenced from the root DAG, referenced from a nested DAG, not referenced
• TestAccept_MissingReferencesNameTheTask: undefined component, undefined executor, undefined executor on the root

Command:

go test ./backend/src/v2/compiler/ -run 'TestAccept_RejectsComponentNamedRoot|TestAccept_MissingReferencesNameTheTask' -count=1 -v

Before the fix:

Error: "circular component reference detected: root -> root. Remove the task that references an enclosing component" does not contain "component name \"root\" is reserved"
Error: "circular component reference detected: root -> comp-a -> root. Remove the task that references an enclosing component" does not contain "component name \"root\" is reserved"
Error: An error is expected but got nil.
--- FAIL: TestAccept_RejectsComponentNamedRoot (0.00s)
    --- FAIL: TestAccept_RejectsComponentNamedRoot/referenced_from_the_root_DAG (0.00s)
    --- FAIL: TestAccept_RejectsComponentNamedRoot/referenced_from_a_nested_DAG (0.00s)
    --- FAIL: TestAccept_RejectsComponentNamedRoot/not_referenced (0.00s)
Error: "error processing component name=\"comp-a\": cannot find component ref name=\"comp-missing\"" does not contain "task \"task-comp-missing\" references component \"comp-missing\""
Error: "error processing component name=\"comp-leaf\": executor(label=\"exec-missing\") not found in deployment config" does not contain "used by task \"task-comp-leaf\" in component \"comp-a\""
--- FAIL: TestAccept_MissingReferencesNameTheTask (0.00s)
    --- FAIL: TestAccept_MissingReferencesNameTheTask/undefined_component (0.00s)
    --- FAIL: TestAccept_MissingReferencesNameTheTask/undefined_executor (0.00s)
FAIL

(The undefined executor on the root case was added with the fix to cover the guard.)

After the fix:

--- PASS: TestAccept_RejectsComponentNamedRoot (0.00s)
    --- PASS: TestAccept_RejectsComponentNamedRoot/referenced_from_the_root_DAG (0.00s)
    --- PASS: TestAccept_RejectsComponentNamedRoot/referenced_from_a_nested_DAG (0.00s)
    --- PASS: TestAccept_RejectsComponentNamedRoot/not_referenced (0.00s)
--- PASS: TestAccept_MissingReferencesNameTheTask (0.00s)
    --- PASS: TestAccept_MissingReferencesNameTheTask/undefined_component (0.00s)
    --- PASS: TestAccept_MissingReferencesNameTheTask/undefined_executor (0.00s)
    --- PASS: TestAccept_MissingReferencesNameTheTask/undefined_executor_on_the_root (0.00s)
ok  	github.com/kubeflow/pipelines/backend/src/v2/compiler

Also run locally:

• go test ./backend/src/v2/compiler/... ./backend/src/apiserver/template/...: pass
• ginkgo ./backend/test/compiler -- -createGoldenFiles=false: 315 passed, 0 failed, 4 skipped (no golden changes)
• golangci-lint run --new-from-rev upstream/master ./backend/src/v2/compiler/... (v2.15.0): 0 issues

Release notes / user impact:

Pipeline specs that define a component named root are rejected with an error saying the name is reserved. SDK-compiled pipelines never use that name. Errors for undefined component refs and executors now name the task holding the reference.

Checklist:

• You have signed off your commits
• The title for your pull request (PR) should follow our title convention. Learn more about the pull request title convention used in this repository.

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[github-actions]

Contributor Report for @jsonmp-k8

Metric	Value
Kubeflow org member	Yes
Issues opened in kubeflow/pipelines	71
Merged PRs in kubeflow/pipelines	54
GitHub account age	2838 days (created 2019-01-23)
PR comments in kubeflow/pipelines	166

[jsonmp-k8]

/ok-to-tws

[jsonmp-k8]

/ok-to-test

[jsonmp-k8]

/ok-to-test