Implement parsing of local imports

.github/workflows/security.yaml

@@ -72,7 +72,7 @@ jobs:
         with:
           distribution: "goreleaser-pro"
           version: "2.3.2"
-          args: "release --clean --split --snapshot --single-target --skip=chocolatey"
+          args: "release --clean --split --snapshot --single-target"
         env:
           GORELEASER_KEY: "${{ secrets.GORELEASER_KEY }}"
       - name: "Obtain container image to scan"

pkg/composableschemadsl/dslshape/dslshape.go

@@ -35,6 +35,8 @@ const (
 	NodeTypeNilExpression // A nil keyword
 
 	NodeTypeCaveatTypeReference // A type reference for a caveat parameter.
+
+	NodeTypeImport
 )
 
 const (
@@ -188,4 +190,12 @@ const (
 	//
 	NodeExpressionPredicateLeftExpr  = "left-expr"
 	NodeExpressionPredicateRightExpr = "right-expr"
+
+	//
+	// NodeTypeImport
+	//
+	// TODO: still need to figure out what form this should take - full path? relative path?
+	NodeImportPredicateSource         = "import-source"
+	NodeImportPredicatePathSegment    = "path-segment"
+	NodeImportPredicateDefinitionName = "imported-definition"
 )

pkg/composableschemadsl/lexer/lex_def.go

@@ -78,6 +78,8 @@ var keywords = map[string]struct{}{
 	"permission": {},
 	"nil":        {},
 	"with":       {},
+	"from":       {},
+	"import":     {},
 }
 
 // IsKeyword returns whether the specified input string is a reserved keyword.

pkg/composableschemadsl/parser/parser.go

@@ -62,6 +62,9 @@ Loop:
 		case p.isKeyword("caveat"):
 			rootNode.Connect(dslshape.NodePredicateChild, p.consumeCaveat())
 
+		case p.isKeyword("from"):
+			rootNode.Connect(dslshape.NodePredicateChild, p.consumeImport())
+
 		default:
 			p.emitErrorf("Unexpected token at root level: %v", p.currentToken.Kind)
 			break Loop
@@ -574,6 +577,20 @@ func (p *sourceParser) tryConsumeIdentifierLiteral() (AstNode, bool) {
 	return identNode, true
 }
 
+// consumeIdentifierLiteral is similar to the above, but attempts and errors
+// rather than checking the token type beforehand
+func (p *sourceParser) consumeIdentifierLiteral() (AstNode, bool) {
+	identNode := p.startNode(dslshape.NodeTypeIdentifier)
+	defer p.mustFinishNode()
+
+	identifier, ok := p.consumeIdentifier()
+	if !ok {
+		return identNode, false
+	}
+	identNode.MustDecorate(dslshape.NodeIdentiferPredicateValue, identifier)
+	return identNode, true
+}
+
 func (p *sourceParser) tryConsumeNilExpression() (AstNode, bool) {
 	if !p.isKeyword("nil") {
 		return nil, false
@@ -584,3 +601,58 @@ func (p *sourceParser) tryConsumeNilExpression() (AstNode, bool) {
 	defer p.mustFinishNode()
 	return node, true
 }
+
+func (p *sourceParser) consumeImport() AstNode {
+	importNode := p.startNode(dslshape.NodeTypeImport)
+	defer p.mustFinishNode()
+
+	// from ...
+	// NOTE: error handling isn't necessary here because this function is only
+	// invoked if the `from` keyword is found in the function above.
+	p.consumeKeyword("from")
+
+	// Consume alternating periods and identifiers
+	for {
+		if _, ok := p.consume(lexer.TokenTypePeriod); !ok {
+			return importNode
+		}
+
+		segmentNode, ok := p.consumeIdentifierLiteral()
+		// We connect the node so that the error information is retained, then break the loop
+		// so that we aren't continuing to attempt to consume.
+		importNode.Connect(dslshape.NodeImportPredicatePathSegment, segmentNode)
+		if !ok {
+			break
+		}
+
+		if !p.isToken(lexer.TokenTypePeriod) {
+			// If we don't have a period as our next token, we move
+			// to the next step of parsing.
+			break
+		}
+	}
+
+	if ok := p.consumeKeyword("import"); !ok {
+		return importNode
+	}
+
+	// Consume alternating identifiers and commas until we reach the end of the import statement
+	for {
+		definitionNode, ok := p.consumeIdentifierLiteral()
+		// We connect the node so that the error information is retained, then break the loop
+		// so that we aren't continuing to attempt to consume.
+		importNode.Connect(dslshape.NodeImportPredicateDefinitionName, definitionNode)
+		if !ok {
+			break
+		}
+
+		if _, ok := p.tryConsumeStatementTerminator(); ok {
+			break
+		}
+		if _, ok := p.consume(lexer.TokenTypeComma); !ok {
+			return importNode
+		}
+	}
+
+	return importNode
+}

pkg/composableschemadsl/parser/parser_test.go

@@ -122,6 +122,13 @@ func TestParser(t *testing.T) {
 		{"arrow illegal operations test", "arrowillegalops"},
 		{"arrow illegal function test", "arrowillegalfunc"},
 		{"caveat with keyword parameter test", "caveatwithkeywordparam"},
+		{"local imports test", "localimport"},
+		{"local imports with keyword in import path test", "localimport_import_path_with_keyword"},
+		{"local imports with keyword in identifiers test", "localimport_keyword_in_identifiers"},
+		{"local imports with malformed identifiers set test", "localimport_malformed_identifier_set"},
+		{"local imports with malformed import path test", "localimport_malformed_import_path"},
+		{"local imports with path missing leading period test", "localimport_path_missing_leading_period"},
+		{"local imports with typo in import separator test", "localimport_typo_in_import_separator"},
 	}
 
 	for _, test := range parserTests {

pkg/composableschemadsl/parser/tests/localimport.zed

@@ -0,0 +1,7 @@
+from .path.to.user import user, persona
+
+definition resource {
+    relation user: user
+    relation persona: persona
+    permission view = user + persona
+}

pkg/composableschemadsl/parser/tests/localimport.zed.expected

@@ -0,0 +1,96 @@
+NodeTypeFile
+  end-rune = 155
+  input-source = local imports test
+  start-rune = 0
+  child-node =>
+    NodeTypeImport
+      end-rune = 39
+      input-source = local imports test
+      start-rune = 0
+      imported-definition =>
+        NodeTypeIdentifier
+          end-rune = 29
+          identifier-value = user
+          input-source = local imports test
+          start-rune = 26
+        NodeTypeIdentifier
+          end-rune = 38
+          identifier-value = persona
+          input-source = local imports test
+          start-rune = 32
+      path-segment =>
+        NodeTypeIdentifier
+          end-rune = 9
+          identifier-value = path
+          input-source = local imports test
+          start-rune = 6
+        NodeTypeIdentifier
+          end-rune = 12
+          identifier-value = to
+          input-source = local imports test
+          start-rune = 11
+        NodeTypeIdentifier
+          end-rune = 17
+          identifier-value = user
+          input-source = local imports test
+          start-rune = 14
+    NodeTypeDefinition
+      definition-name = resource
+      end-rune = 154
+      input-source = local imports test
+      start-rune = 41
+      child-node =>
+        NodeTypeRelation
+          end-rune = 85
+          input-source = local imports test
+          relation-name = user
+          start-rune = 67
+          allowed-types =>
+            NodeTypeTypeReference
+              end-rune = 85
+              input-source = local imports test
+              start-rune = 82
+              type-ref-type =>
+                NodeTypeSpecificTypeReference
+                  end-rune = 85
+                  input-source = local imports test
+                  start-rune = 82
+                  type-name = user
+        NodeTypeRelation
+          end-rune = 115
+          input-source = local imports test
+          relation-name = persona
+          start-rune = 91
+          allowed-types =>
+            NodeTypeTypeReference
+              end-rune = 115
+              input-source = local imports test
+              start-rune = 109
+              type-ref-type =>
+                NodeTypeSpecificTypeReference
+                  end-rune = 115
+                  input-source = local imports test
+                  start-rune = 109
+                  type-name = persona
+        NodeTypePermission
+          end-rune = 152
+          input-source = local imports test
+          relation-name = view
+          start-rune = 121
+          compute-expression =>
+            NodeTypeUnionExpression
+              end-rune = 152
+              input-source = local imports test
+              start-rune = 139
+              left-expr =>
+                NodeTypeIdentifier
+                  end-rune = 142
+                  identifier-value = user
+                  input-source = local imports test
+                  start-rune = 139
+              right-expr =>
+                NodeTypeIdentifier
+                  end-rune = 152
+                  identifier-value = persona
+                  input-source = local imports test
+                  start-rune = 146

pkg/composableschemadsl/parser/tests/localimport_import_path_with_keyword.zed

@@ -0,0 +1,7 @@
+from .path.definition.user import user, persona
+
+definition resource {
+    relation user: user
+    relation persona: persona
+    permission view = user + persona
+}

pkg/composableschemadsl/parser/tests/localimport_import_path_with_keyword.zed.expected

@@ -0,0 +1,50 @@
+NodeTypeFile
+  end-rune = 20
+  input-source = local imports with keyword in import path test
+  start-rune = 0
+  child-node =>
+    NodeTypeImport
+      end-rune = 10
+      input-source = local imports with keyword in import path test
+      start-rune = 0
+      child-node =>
+        NodeTypeError
+          end-rune = 10
+          error-message = Expected keyword import, found token TokenTypeKeyword
+          error-source = definition
+          input-source = local imports with keyword in import path test
+          start-rune = 11
+      path-segment =>
+        NodeTypeIdentifier
+          end-rune = 9
+          identifier-value = path
+          input-source = local imports with keyword in import path test
+          start-rune = 6
+        NodeTypeIdentifier
+          end-rune = 10
+          input-source = local imports with keyword in import path test
+          start-rune = 11
+          child-node =>
+            NodeTypeError
+              end-rune = 10
+              error-message = Expected identifier, found token TokenTypeKeyword
+              error-source = definition
+              input-source = local imports with keyword in import path test
+              start-rune = 11
+    NodeTypeDefinition
+      end-rune = 20
+      input-source = local imports with keyword in import path test
+      start-rune = 11
+      child-node =>
+        NodeTypeError
+          end-rune = 20
+          error-message = Expected identifier, found token TokenTypePeriod
+          error-source = .
+          input-source = local imports with keyword in import path test
+          start-rune = 21
+    NodeTypeError
+      end-rune = 20
+      error-message = Unexpected token at root level: TokenTypePeriod
+      error-source = .
+      input-source = local imports with keyword in import path test
+      start-rune = 21

pkg/composableschemadsl/parser/tests/localimport_keyword_in_identifiers.zed

@@ -0,0 +1,7 @@
+from .path.to.user import user, caveat
+
+definition resource {
+    relation user: user
+    relation persona: persona
+    permission view = user + persona
+}