Do fail on a possible typo in `needs` entries (#2026)

* Do fail on a possible typo in `needs` entries Helmfile kindly fails with a friendly error when you made a typo in a `needs` entry, i.e. a `needs` entry included a reference to a release that is not defined in the helmfile config. Example Output: ``` in ./helmfile.needs.yaml: release(s) "app" depend(s) on an undefined release "infrastructure/cert-manager2". Perhaps you made a typo in `needs` or forgot defining a release named "cert-manager2" with appropriate `namespace` and `kubeContext`? ``` This prevents issues like #1959 * Fix regression in helmfile-diff (This may break when you had two or more duplicated releases that are intended to be de-duplicated before DAG calculation using selectors * Fix regression when you used selector to deduplicate releases before DAG calculation * Comments * Fix regressions in helmfile-apply and helmfile-sync * Fix regression in duplicate release detection
2021-12-18 17:44:55 +09:00 · 2021-12-18 17:44:55 +09:00 · 9efb7afb47
parent 3d7b4287b3
commit 9efb7afb47
8 changed files with 289 additions and 74 deletions
--- a/go.mod
+++ b/go.mod
@ -29,7 +29,7 @@ require (
 	github.com/tatsushid/go-prettytable v0.0.0-20141013043238-ed2d14c29939
 	github.com/urfave/cli v1.22.5
 	github.com/variantdev/chartify v0.9.1
-	github.com/variantdev/dag v1.0.0
+	github.com/variantdev/dag v1.1.0
 	github.com/variantdev/vals v0.14.0
 	go.uber.org/multierr v1.6.0
 	go.uber.org/zap v1.16.0
--- a/go.sum
+++ b/go.sum
@ -602,6 +602,8 @@ github.com/variantdev/chartify v0.9.1 h1:Mkq2BvtHr42BYf2a14YWkfeSoY/+d1wL2xfap4q
 github.com/variantdev/chartify v0.9.1/go.mod h1:qF4XzQlkfH/6k2jAi1hLas+lK4zSCa8kY+r5JdmLA68=
 github.com/variantdev/dag v1.0.0 h1:7SFjATxHtrYV20P3tx53yNDBMegz6RT4jv8JPHqAHdM=
 github.com/variantdev/dag v1.0.0/go.mod h1:pH1TQsNSLj2uxMo9NNl9zdGy01Wtn+/2MT96BrKmVyE=
+github.com/variantdev/dag v1.1.0 h1:xodYlSng33KWGvIGMpKUyLcIZRXKiNUx612mZJqYrDg=
+github.com/variantdev/dag v1.1.0/go.mod h1:pH1TQsNSLj2uxMo9NNl9zdGy01Wtn+/2MT96BrKmVyE=
 github.com/variantdev/vals v0.14.0 h1:J+zX1DDLTQ35A198HChVkCwLfA/4OeKhSuZ5zjmgV0Q=
 github.com/variantdev/vals v0.14.0/go.mod h1:zoPna6p+fM7pC2Lo17dl5sRpamAV2a0j2VDslkMLW0M=
 github.com/vektra/mockery v1.1.2/go.mod h1:VcfZjKaFOPO+MpN4ZvwPjs4c48lkq1o3Ym8yHZJu0jU=
--- a/pkg/app/app.go
+++ b/pkg/app/app.go
@ -1149,29 +1149,61 @@ func (a *App) getSelectedReleases(r *Run, includeTransitiveNeeds bool) ([]state.
 		return nil, nil, err
 	}

-	selectedIds := map[string]struct{}{}
+	selectedIds := map[string]state.ReleaseSpec{}
+	selectedCounts := map[string]int{}
 	for _, r := range selected {
-		selectedIds[state.ReleaseToID(&r)] = struct{}{}
+		r := r
+		id := state.ReleaseToID(&r)
+		selectedIds[id] = r
+		selectedCounts[id]++
+
+		if dupCount := selectedCounts[id]; dupCount > 1 {
+			return nil, nil, fmt.Errorf("found %d duplicate releases with ID %q", dupCount, id)
+		}
 	}

 	allReleases := r.state.GetReleasesWithOverrides()

-	needed := map[string]struct{}{}
-	for _, r := range selected {
-		collectNeeds(r, selectedIds, needed, allReleases, includeTransitiveNeeds)
-	}
-
-	var releases []state.ReleaseSpec
-
-	releases = append(releases, selected...)
-
+	groupsByID := map[string][]*state.ReleaseSpec{}
 	for _, r := range allReleases {
-		if _, ok := needed[state.ReleaseToID(&r)]; ok {
-			releases = append(releases, r)
-		}
+		r := r
+		groupsByID[state.ReleaseToID(&r)] = append(groupsByID[state.ReleaseToID(&r)], &r)
 	}

-	if err := checkDuplicates(r.helm, r.state, releases); err != nil {
+	var deduplicated []state.ReleaseSpec
+
+	dedupedBefore := map[string]struct{}{}
+
+	// We iterate over allReleases rather than groupsByID
+	// to preserve the order of releases
+	for _, seq := range allReleases {
+		id := state.ReleaseToID(&seq)
+
+		rs := groupsByID[id]
+
+		if len(rs) == 1 {
+			deduplicated = append(deduplicated, *rs[0])
+			continue
+		}
+
+		if _, ok := dedupedBefore[id]; ok {
+			continue
+		}
+
+		// We keep the selected one only when there were two or more duplicate
+		// releases in the helmfile config.
+		// Otherwise we can't compute the DAG of releases correctly.
+		r, deduped := selectedIds[id]
+		if !deduped {
+			panic(fmt.Errorf("assertion error: release %q has never been selected. This shouldn't happen!", id))
+		}
+
+		deduplicated = append(deduplicated, r)
+
+		dedupedBefore[id] = struct{}{}
+	}
+
+	if err := checkDuplicates(r.helm, r.state, deduplicated); err != nil {
 		return nil, nil, err
 	}

@ -1183,42 +1215,7 @@ func (a *App) getSelectedReleases(r *Run, includeTransitiveNeeds bool) ([]state.

 	a.Logger.Debugf("%d release(s)%s found in %s\n", len(selected), extra, r.state.FilePath)

-	return selected, releases, nil
-}
-
-func collectNeeds(release state.ReleaseSpec, selectedIds map[string]struct{}, needed map[string]struct{}, allReleases []state.ReleaseSpec, includeTransitiveNeeds bool) {
-	for _, id := range release.Needs {
-		// Avoids duplicating a release that is selected AND also needed by another selected release
-		if _, ok := selectedIds[id]; !ok {
-			if _, ok := needed[id]; !ok {
-				needed[id] = struct{}{}
-				if includeTransitiveNeeds {
-					releaseParts := strings.Split(id, "/")
-					releasePartsCount := len(releaseParts)
-					releaseName := releaseParts[releasePartsCount-1]
-					releaseNamespace := ""
-					releaseKubeContext := ""
-					if releasePartsCount > 1 {
-						releaseNamespace = releaseParts[releasePartsCount-2]
-					}
-					if releasePartsCount > 2 {
-						releaseKubeContext = releaseParts[releasePartsCount-3]
-					}
-					for _, r := range allReleases {
-						if len(releaseNamespace) > 0 && r.Namespace != releaseNamespace {
-							continue
-						}
-						if len(releaseKubeContext) > 0 && r.KubeContext != releaseKubeContext {
-							continue
-						}
-						if r.Name == releaseName {
-							collectNeeds(r, selectedIds, needed, allReleases, includeTransitiveNeeds)
-						}
-					}
-				}
-			}
-		}
-	}
+	return selected, deduplicated, nil
 }

 func (a *App) apply(r *Run, c ApplyConfigProvider) (bool, bool, []error) {
@ -1323,6 +1320,9 @@ Do you really want to apply?

 	affectedReleases := state.AffectedReleases{}

+	// Traverse DAG of all the releases so that we don't suffer from false-positive missing dependencies
+	st.Releases = selectedAndNeededReleases
+
 	if !interactive || interactive && r.askForConfirmation(confMsg) {
 		r.helm.SetExtraArgs(argparser.GetArgs(c.Args(), r.state)...)

@ -1458,7 +1458,7 @@ Do you really want to delete?
 func (a *App) diff(r *Run, c DiffConfigProvider) (*string, bool, bool, []error) {
 	st := r.state

-	selectedReleases, selectedAndNeededReleases, err := a.getSelectedReleases(r, false)
+	selectedReleases, deduplicatedReleases, err := a.getSelectedReleases(r, false)
 	if err != nil {
 		return nil, false, false, []error{err}
 	}
@ -1477,7 +1477,7 @@ func (a *App) diff(r *Run, c DiffConfigProvider) (*string, bool, bool, []error)
 		SkipDiffOnInstall: c.SkipDiffOnInstall(),
 	}

-	st.Releases = selectedAndNeededReleases
+	st.Releases = deduplicatedReleases

 	plan, err := st.PlanReleases(state.PlanOptions{Reverse: false, SelectedReleases: selectedReleases, SkipNeeds: c.SkipNeeds(), IncludeNeeds: c.IncludeNeeds(), IncludeTransitiveNeeds: false})
 	if err != nil {
@ -1731,7 +1731,7 @@ func (a *App) sync(r *Run, c SyncConfigProvider) (bool, []error) {
 	r.helm.SetExtraArgs(argparser.GetArgs(c.Args(), r.state)...)

 	// Traverse DAG of all the releases so that we don't suffer from false-positive missing dependencies
-	st.Releases = toSyncWithNeeds
+	st.Releases = selectedAndNeededReleases

 	affectedReleases := state.AffectedReleases{}

--- a/pkg/app/app_test.go
+++ b/pkg/app/app_test.go
@ -4213,6 +4213,69 @@ merged environment: &{default map[] map[]}
 		//
 		// error cases
 		//
+		{
+			name:      "unselected release in needs",
+			loc:       location(),
+			selectors: []string{"name=foo"},
+			files: map[string]string{
+				"/path/to/helmfile.yaml": `
+releases:
+- name: bar
+  namespace: ns1
+  chart: mychart3
+- name: foo
+  chart: mychart1
+  needs:
+  - ns1/bar
+`,
+			},
+			diffs: map[exectest.DiffKey]error{
+				exectest.DiffKey{Name: "baz", Chart: "mychart3", Flags: "--kube-contextdefault--namespacens1--detailed-exitcode"}: helmexec.ExitError{Code: 2},
+				exectest.DiffKey{Name: "foo", Chart: "mychart1", Flags: "--kube-contextdefault--detailed-exitcode"}:               helmexec.ExitError{Code: 2},
+			},
+			lists:       map[exectest.ListKey]string{},
+			upgraded:    []exectest.Release{},
+			deleted:     []exectest.Release{},
+			concurrency: 1,
+			error:       `in ./helmfile.yaml: release "default//foo" depends on "default/ns1/bar" which does not match the selectors. Please add a selector like "--selector name=bar", or indicate whether to skip (--skip-needs) or include (--include-needs) these dependencies`,
+			log: `processing file "helmfile.yaml" in directory "."
+first-pass rendering starting for "helmfile.yaml.part.0": inherited=&{default map[] map[]}, overrode=<nil>
+first-pass uses: &{default map[] map[]}
+first-pass rendering output of "helmfile.yaml.part.0":
+ 0: 
+ 1: releases:
+ 2: - name: bar
+ 3:   namespace: ns1
+ 4:   chart: mychart3
+ 5: - name: foo
+ 6:   chart: mychart1
+ 7:   needs:
+ 8:   - ns1/bar
+ 9: 
+
+first-pass produced: &{default map[] map[]}
+first-pass rendering result of "helmfile.yaml.part.0": {default map[] map[]}
+vals:
+map[]
+defaultVals:[]
+second-pass rendering result of "helmfile.yaml.part.0":
+ 0: 
+ 1: releases:
+ 2: - name: bar
+ 3:   namespace: ns1
+ 4:   chart: mychart3
+ 5: - name: foo
+ 6:   chart: mychart1
+ 7:   needs:
+ 8:   - ns1/bar
+ 9: 
+
+merged environment: &{default map[] map[]}
+1 release(s) matching name=foo found in helmfile.yaml
+
+err: release "default//foo" depends on "default/ns1/bar" which does not match the selectors. Please add a selector like "--selector name=bar", or indicate whether to skip (--skip-needs) or include (--include-needs) these dependencies
+`,
+		},
 		{
 			name: "non-existent release in needs",
 			loc:  location(),
@ -4225,18 +4288,18 @@ releases:
 - name: foo
  chart: mychart1
  needs:
-  - bar
+  - ns1/bar
 `,
 			},
 			diffs: map[exectest.DiffKey]error{
-				exectest.DiffKey{Name: "baz", Chart: "mychart3", Flags: "--kube-contextdefault--namespacens1--detailed-exitcode"}: helmexec.ExitError{Code: 2},
+				exectest.DiffKey{Name: "bar", Chart: "mychart3", Flags: "--kube-contextdefault--namespacens1--detailed-exitcode"}: helmexec.ExitError{Code: 2},
 				exectest.DiffKey{Name: "foo", Chart: "mychart1", Flags: "--kube-contextdefault--detailed-exitcode"}:               helmexec.ExitError{Code: 2},
 			},
 			lists:       map[exectest.ListKey]string{},
 			upgraded:    []exectest.Release{},
 			deleted:     []exectest.Release{},
 			concurrency: 1,
-			error:       `in ./helmfile.yaml: release "default//foo" depends on "default//bar" which does not match the selectors. Please add a selector like "--selector name=bar", or indicate whether to skip (--skip-needs) or include (--include-needs) these dependencies`,
+			error:       "in ./helmfile.yaml: release(s) \"default//foo\" depend(s) on an undefined release \"default/ns1/bar\". Perhaps you made a typo in \"needs\" or forgot defining a release named \"bar\" with appropriate \"namespace\" and \"kubeContext\"?",
 			log: `processing file "helmfile.yaml" in directory "."
 first-pass rendering starting for "helmfile.yaml.part.0": inherited=&{default map[] map[]}, overrode=<nil>
 first-pass uses: &{default map[] map[]}
@ -4249,7 +4312,7 @@ first-pass rendering output of "helmfile.yaml.part.0":
 5: - name: foo
 6:   chart: mychart1
 7:   needs:
- 8:   - bar
+ 8:   - ns1/bar
 9: 

 first-pass produced: &{default map[] map[]}
@ -4266,13 +4329,85 @@ second-pass rendering result of "helmfile.yaml.part.0":
 5: - name: foo
 6:   chart: mychart1
 7:   needs:
- 8:   - bar
+ 8:   - ns1/bar
 9: 

 merged environment: &{default map[] map[]}
 2 release(s) found in helmfile.yaml

-err: release "default//foo" depends on "default//bar" which does not match the selectors. Please add a selector like "--selector name=bar", or indicate whether to skip (--skip-needs) or include (--include-needs) these dependencies
+err: release(s) "default//foo" depend(s) on an undefined release "default/ns1/bar". Perhaps you made a typo in "needs" or forgot defining a release named "bar" with appropriate "namespace" and "kubeContext"?
+`,
+		},
+		{
+			name: "duplicate releases",
+			loc:  location(),
+			files: map[string]string{
+				"/path/to/helmfile.yaml": `
+releases:
+- name: bar
+  namespace: ns1
+  chart: mychart3
+- name: foo
+  chart: mychart2
+  needs:
+  - ns1/bar
+- name: foo
+  chart: mychart1
+  needs:
+  - ns1/bar
+`,
+			},
+			diffs: map[exectest.DiffKey]error{
+				exectest.DiffKey{Name: "bar", Chart: "mychart3", Flags: "--kube-contextdefault--namespacens1--detailed-exitcode"}: helmexec.ExitError{Code: 2},
+				exectest.DiffKey{Name: "foo", Chart: "mychart1", Flags: "--kube-contextdefault--detailed-exitcode"}:               helmexec.ExitError{Code: 2},
+			},
+			lists:       map[exectest.ListKey]string{},
+			upgraded:    []exectest.Release{},
+			deleted:     []exectest.Release{},
+			concurrency: 1,
+			error:       "in ./helmfile.yaml: found 2 duplicate releases with ID \"default//foo\"",
+			log: `processing file "helmfile.yaml" in directory "."
+first-pass rendering starting for "helmfile.yaml.part.0": inherited=&{default map[] map[]}, overrode=<nil>
+first-pass uses: &{default map[] map[]}
+first-pass rendering output of "helmfile.yaml.part.0":
+ 0: 
+ 1: releases:
+ 2: - name: bar
+ 3:   namespace: ns1
+ 4:   chart: mychart3
+ 5: - name: foo
+ 6:   chart: mychart2
+ 7:   needs:
+ 8:   - ns1/bar
+ 9: - name: foo
+10:   chart: mychart1
+11:   needs:
+12:   - ns1/bar
+13: 
+
+first-pass produced: &{default map[] map[]}
+first-pass rendering result of "helmfile.yaml.part.0": {default map[] map[]}
+vals:
+map[]
+defaultVals:[]
+second-pass rendering result of "helmfile.yaml.part.0":
+ 0: 
+ 1: releases:
+ 2: - name: bar
+ 3:   namespace: ns1
+ 4:   chart: mychart3
+ 5: - name: foo
+ 6:   chart: mychart2
+ 7:   needs:
+ 8:   - ns1/bar
+ 9: - name: foo
+10:   chart: mychart1
+11:   needs:
+12:   - ns1/bar
+13: 
+
+merged environment: &{default map[] map[]}
+err: found 2 duplicate releases with ID "default//foo"
 `,
 		},
 	}
--- a/pkg/app/diff_nokubectx_test.go
+++ b/pkg/app/diff_nokubectx_test.go
@ -1227,7 +1227,7 @@ releases:
 			upgraded:    []exectest.Release{},
 			deleted:     []exectest.Release{},
 			concurrency: 1,
-			error:       `in ./helmfile.yaml: release "foo" depends on "bar" which does not match the selectors. Please add a selector like "--selector name=bar", or indicate whether to skip (--skip-needs) or include (--include-needs) these dependencies`,
+			error:       `in ./helmfile.yaml: release(s) "foo" depend(s) on an undefined release "bar". Perhaps you made a typo in "needs" or forgot defining a release named "bar" with appropriate "namespace" and "kubeContext"?`,
 			log: `processing file "helmfile.yaml" in directory "."
 first-pass rendering starting for "helmfile.yaml.part.0": inherited=&{default map[] map[]}, overrode=<nil>
 first-pass uses: &{default map[] map[]}
@ -1263,7 +1263,7 @@ second-pass rendering result of "helmfile.yaml.part.0":
 merged environment: &{default map[] map[]}
 2 release(s) found in helmfile.yaml

-err: release "foo" depends on "bar" which does not match the selectors. Please add a selector like "--selector name=bar", or indicate whether to skip (--skip-needs) or include (--include-needs) these dependencies
+err: release(s) "foo" depend(s) on an undefined release "bar". Perhaps you made a typo in "needs" or forgot defining a release named "bar" with appropriate "namespace" and "kubeContext"?
 `,
 		},
 	}
--- a/pkg/app/diff_test.go
+++ b/pkg/app/diff_test.go
@ -1313,6 +1313,68 @@ merged environment: &{default map[] map[]}
 		//
 		// error cases
 		//
+		{
+			name:  "unselected release in needs",
+			loc:   location(),
+			flags: flags{skipNeeds: false},
+			files: map[string]string{
+				"/path/to/helmfile.yaml": `
+releases:
+- name: bar
+  chart: mychart3
+- name: foo
+  chart: mychart1
+  needs:
+  - bar
+`,
+			},
+			detailedExitcode: true,
+			selectors:        []string{"name=foo"},
+			diffs: map[exectest.DiffKey]error{
+				exectest.DiffKey{Name: "bar", Chart: "mychart3", Flags: "--kube-contextdefault--namespacens1--detailed-exitcode"}: helmexec.ExitError{Code: 2},
+				exectest.DiffKey{Name: "foo", Chart: "mychart1", Flags: "--kube-contextdefault--detailed-exitcode"}:               helmexec.ExitError{Code: 2},
+			},
+			lists:       map[exectest.ListKey]string{},
+			upgraded:    []exectest.Release{},
+			deleted:     []exectest.Release{},
+			concurrency: 1,
+			error:       `in ./helmfile.yaml: release "default//foo" depends on "default//bar" which does not match the selectors. Please add a selector like "--selector name=bar", or indicate whether to skip (--skip-needs) or include (--include-needs) these dependencies`,
+			log: `processing file "helmfile.yaml" in directory "."
+first-pass rendering starting for "helmfile.yaml.part.0": inherited=&{default map[] map[]}, overrode=<nil>
+first-pass uses: &{default map[] map[]}
+first-pass rendering output of "helmfile.yaml.part.0":
+ 0: 
+ 1: releases:
+ 2: - name: bar
+ 3:   chart: mychart3
+ 4: - name: foo
+ 5:   chart: mychart1
+ 6:   needs:
+ 7:   - bar
+ 8: 
+
+first-pass produced: &{default map[] map[]}
+first-pass rendering result of "helmfile.yaml.part.0": {default map[] map[]}
+vals:
+map[]
+defaultVals:[]
+second-pass rendering result of "helmfile.yaml.part.0":
+ 0: 
+ 1: releases:
+ 2: - name: bar
+ 3:   chart: mychart3
+ 4: - name: foo
+ 5:   chart: mychart1
+ 6:   needs:
+ 7:   - bar
+ 8: 
+
+merged environment: &{default map[] map[]}
+1 release(s) matching name=foo found in helmfile.yaml
+
+err: release "default//foo" depends on "default//bar" which does not match the selectors. Please add a selector like "--selector name=bar", or indicate whether to skip (--skip-needs) or include (--include-needs) these dependencies
+`,
+		},
 		{
 			name: "non-existent release in needs",
 			loc:  location(),
@ -1337,7 +1399,7 @@ releases:
 			upgraded:    []exectest.Release{},
 			deleted:     []exectest.Release{},
 			concurrency: 1,
-			error:       `in ./helmfile.yaml: release "default//foo" depends on "default//bar" which does not match the selectors. Please add a selector like "--selector name=bar", or indicate whether to skip (--skip-needs) or include (--include-needs) these dependencies`,
+			error:       `in ./helmfile.yaml: release(s) "default//foo" depend(s) on an undefined release "default//bar". Perhaps you made a typo in "needs" or forgot defining a release named "bar" with appropriate "namespace" and "kubeContext"?`,
 			log: `processing file "helmfile.yaml" in directory "."
 first-pass rendering starting for "helmfile.yaml.part.0": inherited=&{default map[] map[]}, overrode=<nil>
 first-pass uses: &{default map[] map[]}
@ -1373,7 +1435,7 @@ second-pass rendering result of "helmfile.yaml.part.0":
 merged environment: &{default map[] map[]}
 2 release(s) found in helmfile.yaml

-err: release "default//foo" depends on "default//bar" which does not match the selectors. Please add a selector like "--selector name=bar", or indicate whether to skip (--skip-needs) or include (--include-needs) these dependencies
+err: release(s) "default//foo" depend(s) on an undefined release "default//bar". Perhaps you made a typo in "needs" or forgot defining a release named "bar" with appropriate "namespace" and "kubeContext"?
 `,
 		},
 	}
--- a/pkg/state/state.go
+++ b/pkg/state/state.go
@ -1888,8 +1888,11 @@ func (st *HelmState) DiffReleases(helm helmexec.Interface, additionalValues []st
 	)

 	for _, p := range preps {
-		if stdout, ok := outputs[ReleaseToID(p.release)]; ok {
+		id := ReleaseToID(p.release)
+		if stdout, ok := outputs[id]; ok {
 			fmt.Print(stdout.String())
+		} else {
+			panic(fmt.Sprintf("missing output for release %s", id))
 		}
 	}

--- a/pkg/state/state_run.go
+++ b/pkg/state/state_run.go
@ -150,15 +150,12 @@ func GroupReleasesByDependency(releases []Release, opts PlanOptions) ([][]Releas
 		idToReleases[id] = append(idToReleases[id], r)
 		idToIndex[id] = i

-		// Only compute dependencies from non-filtered releases
-		if !r.Filtered {
-			var needs []string
-			for i := 0; i < len(r.Needs); i++ {
-				n := r.Needs[i]
-				needs = append(needs, n)
-			}
-			d.Add(id, dag.Dependencies(needs))
+		var needs []string
+		for i := 0; i < len(r.Needs); i++ {
+			n := r.Needs[i]
+			needs = append(needs, n)
 		}
+		d.Add(id, dag.Dependencies(needs))
 	}

 	var ids []string
@ -218,6 +215,22 @@ func GroupReleasesByDependency(releases []Release, opts PlanOptions) ([][]Releas
 				msgs[i] = msg
 			}
 			return nil, errors.New(msgs[0])
+		} else if ude, ok := err.(*dag.UndefinedDependencyError); ok {
+			var quotedReleaseNames []string
+			for _, d := range ude.Dependents {
+				quotedReleaseNames = append(quotedReleaseNames, fmt.Sprintf("%q", d))
+			}
+
+			idComponents := strings.Split(ude.UndefinedNode, "/")
+			name := idComponents[len(idComponents)-1]
+			humanReadableUndefinedReleaseInfo := fmt.Sprintf(`named %q with appropriate "namespace" and "kubeContext"`, name)
+
+			return nil, fmt.Errorf(
+				`release(s) %s depend(s) on an undefined release %q. Perhaps you made a typo in "needs" or forgot defining a release %s?`,
+				strings.Join(quotedReleaseNames, ", "),
+				ude.UndefinedNode,
+				humanReadableUndefinedReleaseInfo,
+			)
 		}
 		return nil, err
 	}