Read a node's adoption from every declaration, so the host knows which modules are untaken (hq ADR 0100)

internal/declaration/adoption_test.go

@@ -0,0 +1,102 @@
+package declaration
+
+import (
+	"strings"
+	"testing"
+)
+
+// Defends novox/hq ADR 0100: every declaration says whether the node is adopted and which of its
+// modules are taken, and the host refuses one it cannot read that from unambiguously.
+
+const adoptedResources = `"resources":[
+	  {"id":"hello-web.page","type":"file","path":"/var/lib/hello-web/index.html","content":"a\n"},
+	  {"id":"hello-web.server","type":"container","name":"hello-web","image":"sha256:` + sixtyFour + `"},
+	  {"id":"hello-web.data","type":"directory","path":"/var/lib/hello-web"}
+	]`
+
+const sixtyFour = "0000000000000000000000000000000000000000000000000000000000000000"
+
+func TestAnAdoptionIsReadWithTheDeclaration(t *testing.T) {
+	d, err := Parse([]byte(`{"adoption":{"taken":["postgres"],"untaken":{"hello-web":["hello-web.page","hello-web.server"]}},
+	  "declaration":1,` + adoptedResources + `}`))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if d.Adoption == nil {
+		t.Fatal("the adoption was dropped")
+	}
+	if len(d.Adoption.Taken) != 1 || d.Adoption.Taken[0] != "postgres" {
+		t.Errorf("taken read as %v", d.Adoption.Taken)
+	}
+	if module, ok := d.Adoption.UntakenModuleOf("hello-web.server"); !ok || module != "hello-web" {
+		t.Errorf("the container's untaken module read as %q, %v", module, ok)
+	}
+	if _, ok := d.Adoption.UntakenModuleOf("hello-web.data"); ok {
+		t.Error("a resource the adoption does not name was said to be untaken")
+	}
+}
+
+func TestADeclarationWithNoAdoptionIsConverged(t *testing.T) {
+	d, err := Parse([]byte(`{"declaration":1,` + adoptedResources + `}`))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if d.Adoption != nil {
+		t.Errorf("a declaration saying nothing about adoption read as adopted: %+v", d.Adoption)
+	}
+	if _, ok := d.Adoption.UntakenModuleOf("hello-web.page"); ok {
+		t.Error("a converged node has an untaken module")
+	}
+}
+
+func TestAnAdoptionNamingAnUnknownIDIsRefused(t *testing.T) {
+	refusal := refusalFor(t, `{"adoption":{"taken":[],"untaken":{"hello-web":["hello-web.missing"]}},
+	  "declaration":1,`+adoptedResources+`}`)
+	if !strings.Contains(strings.Join(refusal.Problems, "\n"), "hello-web.missing") {
+		t.Errorf("the unknown id was not named: %v", refusal.Problems)
+	}
+}
+
+func TestAnAdoptionMayOnlyHoldFilesAndContainers(t *testing.T) {
+	refusal := refusalFor(t, `{"adoption":{"taken":[],"untaken":{"hello-web":["hello-web.data"]}},
+	  "declaration":1,`+adoptedResources+`}`)
+	if !strings.Contains(strings.Join(refusal.Problems, "\n"), "only a file or a container") {
+		t.Errorf("a directory was accepted as holdable: %v", refusal.Problems)
+	}
+}
+
+func TestAnIDUnderTwoModulesIsRefused(t *testing.T) {
+	refusal := refusalFor(t, `{"adoption":{"taken":[],"untaken":{"a":["hello-web.page"],"b":["hello-web.page"]}},
+	  "declaration":1,`+adoptedResources+`}`)
+	if !strings.Contains(strings.Join(refusal.Problems, "\n"), "both") {
+		t.Errorf("an id under two modules was accepted: %v", refusal.Problems)
+	}
+}
+
+func TestAModuleBothTakenAndUntakenIsRefused(t *testing.T) {
+	refusal := refusalFor(t, `{"adoption":{"taken":["hello-web"],"untaken":{"hello-web":["hello-web.page"]}},
+	  "declaration":1,`+adoptedResources+`}`)
+	if !strings.Contains(strings.Join(refusal.Problems, "\n"), "both taken and untaken") {
+		t.Errorf("a module both taken and untaken was accepted: %v", refusal.Problems)
+	}
+}
+
+func TestTheMeshsOwnResourcesAreNeverUntaken(t *testing.T) {
+	refusal := refusalFor(t, `{"adoption":{"taken":[],"untaken":{"x":["adoption.guard"]}},
+	  "declaration":1,"resources":[
+	  {"id":"adoption.guard","type":"file","path":"/etc/mesh/guard.nft","content":"x"}]}`)
+	if !strings.Contains(strings.Join(refusal.Problems, "\n"), "belongs to no module") {
+		t.Errorf("an adoption. id was accepted as untaken: %v", refusal.Problems)
+	}
+}
+
+func TestAnAdoptionWithAnUnknownFieldIsRefused(t *testing.T) {
+	refusalFor(t, `{"adoption":{"taken":[],"held":["x"]},"declaration":1,`+adoptedResources+`}`)
+}
+
+func TestACarriedBundleCannotSayTheNodeIsAdopted(t *testing.T) {
+	_, err := ParseTrusted([]byte(`{"adoption":{"taken":[]},"declaration":1,` + adoptedResources + `}`))
+	if err == nil || !strings.Contains(err.Error(), "only the mesh can say") {
+		t.Fatalf("a bundle claiming adoption was not refused: %v", err)
+	}
+}