feat: Support for CREATE VIEW statements

src/main/java/com/google/cloud/solutions/spannerddl/diff/DatabaseDefinition.java

@@ -27,6 +27,7 @@
 import com.google.cloud.solutions.spannerddl.parser.ASTcreate_schema_statement;
 import com.google.cloud.solutions.spannerddl.parser.ASTcreate_search_index_statement;
 import com.google.cloud.solutions.spannerddl.parser.ASTcreate_table_statement;
+import com.google.cloud.solutions.spannerddl.parser.ASTcreate_view_statement;
 import com.google.cloud.solutions.spannerddl.parser.ASTddl_statement;
 import com.google.cloud.solutions.spannerddl.parser.ASTforeign_key;
 import com.google.cloud.solutions.spannerddl.parser.ASTrow_deletion_policy_clause;
@@ -64,6 +65,7 @@ public static DatabaseDefinition create(List<ASTddl_statement> statements) {
     LinkedHashMap<String, ASTcreate_change_stream_statement> changeStreams = new LinkedHashMap<>();
     LinkedHashMap<String, String> alterDatabaseOptions = new LinkedHashMap<>();
     LinkedHashMap<String, ASTcreate_schema_statement> schemas = new LinkedHashMap<>();
+    LinkedHashMap<String, ASTcreate_view_statement> views = new LinkedHashMap<>();
 
     for (ASTddl_statement ddlStatement : statements) {
       final SimpleNode statement = (SimpleNode) ddlStatement.jjtGetChild(0);
@@ -139,6 +141,14 @@ public static DatabaseDefinition create(List<ASTddl_statement> statements) {
                   (ASTcreate_schema_statement)
                       ((ASTcreate_or_replace_statement) statement).getSchemaObject());
               break;
+            case DdlParserTreeConstants.JJTCREATE_VIEW_STATEMENT:
+              views.put(
+                      ((ASTcreate_view_statement)
+                              ((ASTcreate_or_replace_statement) statement).getSchemaObject())
+                              .getName(),
+                      (ASTcreate_view_statement)
+                              ((ASTcreate_or_replace_statement) statement).getSchemaObject());
+              break;
             default:
               throw new IllegalArgumentException(
                   "Unsupported statement: " + AstTreeUtils.tokensToString(ddlStatement));
@@ -157,7 +167,8 @@ public static DatabaseDefinition create(List<ASTddl_statement> statements) {
         ImmutableMap.copyOf(ttls),
         ImmutableMap.copyOf(changeStreams),
         ImmutableMap.copyOf(alterDatabaseOptions),
-        ImmutableMap.copyOf(schemas));
+        ImmutableMap.copyOf(schemas),
+        ImmutableMap.copyOf(views));
   }
 
   public abstract ImmutableMap<String, ASTcreate_table_statement> tablesInCreationOrder();
@@ -175,4 +186,6 @@ public static DatabaseDefinition create(List<ASTddl_statement> statements) {
   abstract ImmutableMap<String, String> alterDatabaseOptions();
 
   abstract ImmutableMap<String, ASTcreate_schema_statement> schemas();
+
+  abstract ImmutableMap<String, ASTcreate_view_statement> views();
 }

src/main/java/com/google/cloud/solutions/spannerddl/diff/DdlDiff.java

@@ -31,6 +31,7 @@
 import com.google.cloud.solutions.spannerddl.parser.ASTcreate_schema_statement;
 import com.google.cloud.solutions.spannerddl.parser.ASTcreate_search_index_statement;
 import com.google.cloud.solutions.spannerddl.parser.ASTcreate_table_statement;
+import com.google.cloud.solutions.spannerddl.parser.ASTcreate_view_statement;
 import com.google.cloud.solutions.spannerddl.parser.ASTddl_statement;
 import com.google.cloud.solutions.spannerddl.parser.ASTforeign_key;
 import com.google.cloud.solutions.spannerddl.parser.ASToptions_clause;
@@ -103,6 +104,7 @@ public class DdlDiff {
   private final MapDifference<String, ASTcreate_search_index_statement> searchIndexDifferences;
   private final String databaseName; // for alter Database
   private final MapDifference<String, ASTcreate_schema_statement> schemaDifferences;
+  private final MapDifference<String, ASTcreate_view_statement> viewDifferences;
 
   private DdlDiff(DatabaseDefinition originalDb, DatabaseDefinition newDb, String databaseName)
       throws DdlDiffException {
@@ -122,6 +124,7 @@ private DdlDiff(DatabaseDefinition originalDb, DatabaseDefinition newDb, String
     this.searchIndexDifferences =
         Maps.difference(originalDb.searchIndexes(), newDb.searchIndexes());
     this.schemaDifferences = Maps.difference(originalDb.schemas(), newDb.schemas());
+    this.viewDifferences = Maps.difference(originalDb.views(), newDb.views());
 
     if (!alterDatabaseOptionsDifferences.areEqual() && Strings.isNullOrEmpty(databaseName)) {
       // should never happen, but...
@@ -197,6 +200,17 @@ public List<String> generateDifferenceStatements(Map<String, Boolean> options)
       }
     }
 
+    // Drop views in original order
+    for (String viewName : originalDb.views().keySet().asList().reverse()) {
+      if (viewDifferences.entriesDiffering().containsKey(viewName)) {
+        LOG.info( "Dropping changed view for re-creation: {}", viewName);
+        output.add("DROP VIEW " + viewName);
+      } else if (options.get(ALLOW_DROP_STATEMENTS_OPT) && viewDifferences.entriesOnlyOnLeft().containsKey(viewName)){
+        LOG.info( "Dropping deleted view: {}", viewName);
+        output.add("DROP VIEW " + viewName);
+      }
+    }
+
     // drop deleted search indexes.
     if (options.get(ALLOW_DROP_STATEMENTS_OPT)) {
       for (String searchIndexName : searchIndexDifferences.entriesOnlyOnLeft().keySet()) {
@@ -424,7 +438,16 @@ public List<String> generateDifferenceStatements(Map<String, Boolean> options)
     // For each changed search index, apply the add column statements
     output.addAll(searchIndexUpdateStatements.createStatements());
 
-    // Add all new search indexes
+    // Create or alter views in new order.
+    for (ASTcreate_view_statement view : newDb.views().values()) {
+      if (viewDifferences.entriesOnlyOnRight().containsKey(view.getName())) {
+        LOG.info("Creating new view: {}", view.getName());
+        output.add("CREATE OR REPLACE " + view.toStringBase());
+      } else if (viewDifferences.entriesDiffering().containsKey(view.getName())) {
+        LOG.info("Re-creating new view: {}", view.getName());
+        output.add("CREATE OR REPLACE " + view.toStringBase());
+      }
+    }
 
     return output.build();
   }
@@ -813,6 +836,7 @@ public static List<ASTddl_statement> parseDdl(String original, boolean parseAnno
             break;
           case DdlParserTreeConstants.JJTCREATE_INDEX_STATEMENT:
           case DdlParserTreeConstants.JJTALTER_DATABASE_STATEMENT:
+          case DdlParserTreeConstants.JJTCREATE_VIEW_STATEMENT:
           case DdlParserTreeConstants.JJTCREATE_CHANGE_STREAM_STATEMENT:
           case DdlParserTreeConstants.JJTCREATE_SEARCH_INDEX_STATEMENT:
             // no-op - allowed
@@ -823,6 +847,7 @@ public static List<ASTddl_statement> parseDdl(String original, boolean parseAnno
                 .getSchemaObject()
                 .getId()) {
               case DdlParserTreeConstants.JJTCREATE_SCHEMA_STATEMENT:
+              case DdlParserTreeConstants.JJTCREATE_VIEW_STATEMENT:
                 // no-op - allowed
                 break;
               default:

src/main/java/com/google/cloud/solutions/spannerddl/parser/ASTcreate_view_statement.java

@@ -15,15 +15,60 @@
  */
 package com.google.cloud.solutions.spannerddl.parser;
 
-// TODO
+import com.google.cloud.solutions.spannerddl.diff.AstTreeUtils;
+import com.google.common.base.Joiner;
+import com.google.common.collect.ImmutableSet;
+
 public class ASTcreate_view_statement extends SimpleNode {
   public ASTcreate_view_statement(int id) {
     super(id);
-    throw new UnsupportedOperationException("Not Implemented");
   }
 
   public ASTcreate_view_statement(DdlParser p, int id) {
     super(p, id);
-    throw new UnsupportedOperationException("Not Implemented");
+  }
+
+  public String toStringBase() {
+    validateChildren();
+    return Joiner.on(" ")
+            .skipNulls()
+            .join(
+                    "VIEW",
+                    getName(),
+                    "SQL SECURITY",
+                    AstTreeUtils.tokensToString(AstTreeUtils.getOptionalChildByType(children, ASTsql_security.class)),
+                    "AS",
+                    AstTreeUtils.tokensToString(AstTreeUtils.getOptionalChildByType(children, ASTview_definition.class))
+                    );
+  }
+
+  private void validateChildren() {
+    AstTreeUtils.validateChildrenClasses(
+            children, ImmutableSet.of(ASTname.class, ASTsql_security.class, ASTview_definition.class));
+  }
+
+  public String getName() {
+    return AstTreeUtils.tokensToString(AstTreeUtils.getChildByType(children, ASTname.class), false);
+  }
+
+  @Override
+  public String toString() {
+    return Joiner.on(" ")
+            .skipNulls()
+            .join(
+                    "CREATE",
+                    toStringBase()
+                    );
+  }
+
+
+  @Override
+  public boolean equals(Object obj) {
+    return (obj instanceof ASTcreate_view_statement) && toString().equals(obj.toString());
+  }
+
+  @Override
+  public int hashCode() {
+    return toString().hashCode();
   }
 }

src/test/java/com/google/cloud/solutions/spannerddl/diff/DdlDiffFromFilesTest.java

@@ -87,6 +87,20 @@ public void compareDddTextFiles() throws IOException {
                             ".*DROP (SCHEMA|TABLE|COLUMN|CHANGE STREAM|SEARCH INDEX).*"))
                 .collect(Collectors.toList());
 
+        // remove any drop views from the expectedResults if they do not have an equivalent
+        // CREATE statement. This is because we are allowing recreation of views, but not allowing
+        // dropping of removed views.
+        for (String statement : expectedDiff) {
+          if (statement.startsWith("DROP VIEW ")) {
+            String viewName = Iterables.get(Splitter.on(' ').split(statement), 2);
+            // see if there is a matching create statement
+            Pattern p = Pattern.compile("CREATE .*VIEW " + viewName + " ");
+            if (expectedDiffNoDrops.stream().noneMatch(s -> p.matcher(s).find())) {
+              expectedDiffNoDrops.remove(statement);
+            }
+          }
+        }
+
         // remove any drop indexes from the expectedResults if they do not have an equivalent
         // CREATE statement. This is because we are allowing recreation of indexes, but not allowing
         // dropping of removed indexes.

src/test/resources/ddlParserUnsupported.txt

@@ -24,14 +24,6 @@ ALTER TABLE Albums DROP ROW DELETION POLICY
 ALTER TABLE Albums
 REPLACE ROW DELETION POLICY (OLDER_THAN(timestamp_column, INTERVAL 1 DAY))
 
-== Test 3
-
-CREATE OR REPLACE VIEW test1 SQL SECURITY INVOKER AS SELECT * from test2
-
-== Test 4
-
-CREATE  VIEW test1 SQL SECURITY INVOKER AS SELECT * from test2
-
 == Test 6
 
 drop change stream test1
@@ -68,18 +60,6 @@ GRANT SELECT ON TABLE table_list TO ROLE role_list
 
 REVOKE SELECT ON TABLE table_list TO ROLE role_list
 
-== Test 12a // TODO views
-
-CREATE VIEW view_name AS query
-
-== Test 12b drop view not supported
-
-DROP VIEW view_name
-
-== Test 13 // TODO views
-
-CREATE OR REPLACE VIEW view_name AS query
-
 == Test 14a // TODO sequences
 
 CREATE SEQUENCE IF NOT EXISTS sequence_name OPTIONS ( sequence_kind='bit_reversed_positive' )
@@ -163,4 +143,4 @@ ALTER SEARCH INDEX AlbumsIndex ADD STORED COLUMN test
 
 ALTER SEARCH INDEX AlbumsIndex ADD COLUMN add_token_column
 
-==
+==

src/test/resources/expectedDdlDiff.txt

@@ -350,4 +350,30 @@ DROP SCHEMA schema2
 CREATE SCHEMA schema3
 CREATE TABLE schema3.table1 ( col1 INT64 ) PRIMARY KEY (col1 ASC)
 
-==
+== TEST 68 Create view with/without named schama
+
+CREATE SCHEMA schema1
+CREATE TABLE input ( PK INT64 ) PRIMARY KEY (PK ASC)
+CREATE TABLE schema1.input ( PK INT64 ) PRIMARY KEY (PK ASC)
+CREATE OR REPLACE VIEW preprocess SQL SECURITY INVOKER AS SELECT t.PK, 1 AS n FROM INPUT AS t
+CREATE OR REPLACE VIEW final SQL SECURITY INVOKER AS SELECT v.PK, v.n, "foo" AS s FROM preprocess AS v
+CREATE OR REPLACE VIEW schema1.preprocess SQL SECURITY INVOKER AS SELECT t.PK, 1 AS n FROM schema1.INPUT AS t
+CREATE OR REPLACE VIEW schema1.final SQL SECURITY INVOKER AS SELECT v.PK, v.n, "foo" AS s FROM schema1.preprocess AS v
+
+
+== TEST 69 Replace view with dependencies
+
+DROP VIEW final
+DROP VIEW preprocess
+DROP INDEX inputByCol
+ALTER TABLE input DROP COLUMN col1
+ALTER TABLE input ADD COLUMN col2 INT64
+CREATE INDEX inputByCol ON INPUT ( col2 ASC )
+CREATE OR REPLACE VIEW preprocess SQL SECURITY INVOKER AS SELECT t.pk, t.col2, 1 AS n FROM INPUT AS t
+CREATE OR REPLACE VIEW final SQL SECURITY INVOKER AS SELECT v.PK, v.col2, v.n, "foo" AS s FROM preprocess AS v
+
+== TEST 70 Dropping view
+
+DROP VIEW view2
+
+==

src/test/resources/newDdl.txt

@@ -563,4 +563,51 @@ CREATE TABLE schema3.table1 (
   col1 INT64,
 )PRIMARY KEY (col1);
 
-==
+== TEST 68 Create view with/without named schama
+
+CREATE TABLE input (
+  PK INT64
+) PRIMARY KEY (PK);
+CREATE OR REPLACE VIEW preprocess
+SQL SECURITY INVOKER
+AS SELECT t.PK, 1 AS n
+   FROM input AS t;
+CREATE OR REPLACE VIEW final
+SQL SECURITY INVOKER
+AS SELECT v.PK, v.n, "foo" AS s
+   FROM preprocess AS v;
+CREATE SCHEMA schema1;
+CREATE TABLE schema1.input (PK INT64) PRIMARY KEY (PK);
+CREATE OR REPLACE VIEW schema1.preprocess
+SQL SECURITY INVOKER
+AS SELECT t.PK, 1 AS n
+   FROM schema1.input AS t;
+CREATE OR REPLACE VIEW schema1.final
+SQL SECURITY INVOKER
+AS SELECT v.PK, v.n, "foo" AS s
+   FROM schema1.preprocess AS v;
+
+== TEST 69 Replace view with dependencies
+
+CREATE TABLE input (
+  pk INT64,
+  col2 INT64
+) PRIMARY KEY (pk);
+
+CREATE INDEX inputByCol ON input (col2);
+
+CREATE OR REPLACE VIEW preprocess
+SQL SECURITY INVOKER
+AS SELECT t.pk, t.col2, 1 AS n
+   FROM input AS t;
+
+CREATE OR REPLACE VIEW final
+SQL SECURITY INVOKER
+AS SELECT v.PK, v.col2, v.n, "foo" AS s
+   FROM preprocess AS v;
+
+== TEST 70 Dropping view
+
+CREATE VIEW view1 SQL SECURITY INVOKER AS SELECT * from test1;
+
+==

src/test/resources/originalDdl.txt

@@ -561,4 +561,32 @@ CREATE TABLE schema2.table1 (
 )PRIMARY KEY (col1);
 
 
-==
+== TEST 68 Create view with/without named schama
+
+-- nothing
+
+== TEST 69 Replace view with dependencies
+
+CREATE TABLE input (
+  pk INT64,
+  col1 INT64
+) PRIMARY KEY (pk);
+
+CREATE INDEX inputByCol ON input (col1);
+
+CREATE OR REPLACE VIEW preprocess
+SQL SECURITY INVOKER
+AS SELECT t.pk, t.col1, 1 AS n
+   FROM input AS t;
+
+CREATE OR REPLACE VIEW final
+SQL SECURITY INVOKER
+AS SELECT v.PK, v.col1, v.n, "foo" AS s
+   FROM preprocess AS v;
+
+== TEST 70 Dropping view
+
+CREATE VIEW view1 SQL SECURITY INVOKER AS SELECT * FROM test1;
+CREATE OR REPLACE VIEW view2 SQL SECURITY DEFINER AS SELECT * FROM test2;
+
+==