Skeleton of bottom-up FDW

pljava-api/src/main/java/org/postgresql/pljava/annotation/BaseFDW.java

@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2015-2022 Tada AB and other contributors, as listed below.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the The BSD 3-Clause License
+ * which accompanies this distribution, and is available at
+ * http://opensource.org/licenses/BSD-3-Clause
+ *
+ * Contributors:
+ *   Chapman Flack
+ */
+package org.postgresql.pljava.annotation;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+import java.sql.SQLData; // referred to in javadoc
+
+/**
+ * Annotation on a PL/Java class that will ...
+ *
+ * Note: we need to handle wrapper, server, and table with
+ * correct precedence.
+ *
+ * Note: we will want method-level annotations as well.
+ */
+@Target(ElementType.TYPE) @Retention(RetentionPolicy.CLASS) @Documented
+public @interface BaseFDW
+{
+    Class<? extends Relation> relationClass();
+}

pljava-api/src/main/java/org/postgresql/pljava/annotation/BaseFDWMethod.java

@@ -0,0 +1,101 @@
+/*
+ * Copyright (c) 2015-2022 Tada AB and other contributors, as listed below.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the The BSD 3-Clause License
+ * which accompanies this distribution, and is available at
+ * http://opensource.org/licenses/BSD-3-Clause
+ *
+ * Contributors:
+ *   Chapman Flack
+ */
+package org.postgresql.pljava.annotation;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+import java.sql.SQLData; // referred to in javadoc
+
+/**
+ * Annotation on a PL/Java method that will ...
+ *
+ * Would this be better handled via a standardized interface?
+ * Or by breaking the enums apart and using logic later?...
+ */
+@Target(ElementType.METHOD) @Retention(RetentionPolicy.CLASS) @Documented
+public @interface BaseFDWMethod
+{
+    enum Operation {
+        // initialization...
+        GET_REL_SIZE,
+        GET_PATHS,
+
+        // preparation and cleanup
+        SCAN_PLAN,
+        SCAN_OPEN,
+        SCAN_CLOSE,
+        SCAN_EXPLAIN,
+
+        INSERT_PLAN,
+        INSERT_OPEN,
+        INSERT_CLOSE,
+
+        MODIFY_PLAN,
+        MODIFY_OPEN,
+        MODIFY_CLOSE,
+        MODIFY_EXPLAIN,
+
+        DIRECT_PLAN,
+        DIRECT_OPEN,
+        DIRECT_CLOSE,
+        DIRECT_EXPLAIN,
+
+        GET_SCAN_BATCH_SIZE,
+        GET_MODIFY_BATCH_SIZE,
+        GET_DIRECT_BATCH_SIZE,
+
+        // actual data transfer
+        NEXT,
+        RESET,
+
+        INSERT,
+        INSERT_BATCH,
+
+        UPDATE,
+        DELETE,
+        TRUNCATE,
+
+        // some of the rest...
+        SUPPORTS_PARALLEL_SCANS,
+        SUPPORTS_ASYNCHRONOUS_EXECUTION,
+
+        VACUUM,
+        ANALYZE,
+
+        IMPORT_SCHEMA_STATEMENT,
+
+        //...
+    };
+
+    Operation operation();
+
+    // an alternative...
+    enum Step {
+        PLAN,
+        OPEN,
+        CLOSE,
+        EXPLAIN
+    };
+
+    enum Operation1 {
+        SCAN,
+        INSERT,
+        UPDATE,
+        DELETE
+        // TRUNCATE
+    };
+
+}

pljava-api/src/main/java/org/postgresql/pljava/annotation/BaseFDWValidator.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright (c) 2015-2022 Tada AB and other contributors, as listed below.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the The BSD 3-Clause License
+ * which accompanies this distribution, and is available at
+ * http://opensource.org/licenses/BSD-3-Clause
+ *
+ * Contributors:
+ *   Chapman Flack
+ */
+package org.postgresql.pljava.annotation;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+import java.sql.SQLData; // referred to in javadoc
+
+/**
+ * Annotation on a PL/Java class that will ...
+ *
+ * This assumes a Builder pattern built on top of the
+ * FdwValidator API.
+ *
+ * Note: we need to handle wrapper, server, and table with
+ * correct precedence.
+ *
+ * Note: we may not need method level annotations since we
+ * only need to worry about two methods and they can be
+ * specified here.
+ */
+@Target(ElementType.TYPE) @Retention(RetentionPolicy.CLASS) @Documented
+public @interface BaseFDW
+{
+    Class<? extends Relation> relationClass();
+}

pljava-api/src/main/java/org/postgresql/pljava/annotation/MappedFDW.java

@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2015-2020 Tada AB and other contributors, as listed below.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the The BSD 3-Clause License
+ * which accompanies this distribution, and is available at
+ * http://opensource.org/licenses/BSD-3-Clause
+ *
+ * Contributors:
+ *   Chapman Flack
+ */
+package org.postgresql.pljava.annotation;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+import java.sql.SQLData; // referred to in javadoc
+
+/**
+ * Annotation on a PL/Java class that will ...
+ *
+ * Note: we need to handle wrapper, server, and table with
+ * correct precedence.
+ *
+ * Note: we will want method-level annotations as well.
+ */
+
+@Target(ElementType.TYPE) @Retention(RetentionPolicy.CLASS) @Documented
+public @interface MappedFDW
+{
+    Class<? extends Relation> relationClass();
+}

pljava-api/src/main/java/org/postgresql/pljava/annotation/MappedFDWValidator.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright (c) 2015-2022 Tada AB and other contributors, as listed below.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the The BSD 3-Clause License
+ * which accompanies this distribution, and is available at
+ * http://opensource.org/licenses/BSD-3-Clause
+ *
+ * Contributors:
+ *   Chapman Flack
+ */
+package org.postgresql.pljava.annotation;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+import java.sql.SQLData; // referred to in javadoc
+
+/**
+ * Annotation on a PL/Java class that will ...
+ *
+ * This assumes a Builder pattern built on top of the
+ * FdwValidator API.
+ *
+ * Note: we need to handle wrapper, server, and table with
+ * correct precedence.
+ *
+ * Note: we may not need method level annotations since we
+ * only need to worry about two methods and they can be
+ * specified here.
+ */
+@Target(ElementType.TYPE) @Retention(RetentionPolicy.CLASS) @Documented
+public @interface BaseFDW
+{
+    Class<? extends Relation> relationClass();
+}

pljava-so/src/main/c/Function.c

@@ -93,6 +93,11 @@ struct Function_
 	 */
 	bool   isUDT;
 
+	/**
+	 * True if this is a FDW function (open/next/reset/close/...)
+	 */
+	bool   isFDW;
+
 	/**
 	 * Java class, i.e. the UDT class or the class where the static method
 	 * is defined.
@@ -163,6 +168,19 @@ struct Function_
 		 */
 		UDTFunction udtFunction;
 		} udt;
+
+		struct
+		{
+			/**
+			 * The FDW that this function is associated with
+			 */
+			FDW fdw;
+
+			/**
+			 * The UDT function to call - there are many...
+			 */
+			// FDWFunction fdwFunction;
+		} fdw;
 	} func;
 };
 
@@ -181,7 +199,7 @@ static void _Function_finalize(PgObject func)
 	Function self = (Function)func;
 	JNI_deleteGlobalRef(self->clazz);
 	JNI_deleteGlobalRef(self->schemaLoader);
-	if(!self->isUDT)
+	if(!self->isUDT && !self->isFDW)
 	{
 		JNI_deleteGlobalRef(self->func.nonudt.invocable);
 		if(self->func.nonudt.typeMap != 0)
@@ -781,7 +799,7 @@ static Function Function_create(
 		self->func.nonudt.invocable = JNI_newGlobalRef(invocable);
 		JNI_deleteLocalRef(invocable);
 	}
-	else if ( ! self->isUDT )
+	else if ( ! self->isUDT && ! self->isFDW )
 	{
 		pfree(self);
 		if ( forValidator )
@@ -920,6 +938,11 @@ Function_invoke(
 	if(self->isUDT)
 		return self->func.udt.udtFunction(self->func.udt.udt, fcinfo);
 
+	if(self->isFDW)
+    {
+    //    return self->func.fdw.fdw(self->func.fdw.fdw, fcinfo);
+    }
+
 	if ( self->func.nonudt.isMultiCall )
 	{
 		if ( SRF_IS_FIRSTCALL() )
@@ -1166,6 +1189,7 @@ JNIEXPORT jboolean JNICALL
 	PG_TRY();
 	{
 		self->isUDT = false;
+		self->isFDW = false;
 		self->readOnly = (JNI_TRUE == readOnly);
 		self->schemaLoader = JNI_newGlobalRef(schemaLoader);
 		self->clazz = JNI_newGlobalRef(clazz);
@@ -1281,6 +1305,7 @@ JNIEXPORT void JNICALL
 		 * In that case, don't store anything needing special deallocation
 		 * such as JNI references; Function_create will do a blind pfree only.
 		 */
+// FIXME: isFDW?
 		if ( pgType->typisdefined )
 		{
 			self->isUDT = true;