fix(interactive): Support Start Tag for Graph Operators in Compiler (#…

…3376)

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## What do these changes do?
In the query 'g.V().as('a')...select('a').out()', the 'out()' operator
must begin from the 'a' tag. The pull request (PR) modifies the
compiler's graph operator structure to fulfill this requirement.

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## Related issue number

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change? -->

Fixes

interactive_engine/compiler/src/main/java/com/alibaba/graphscope/common/ir/planner/GraphFieldTrimmer.java

@@ -14,7 +14,10 @@
 import com.alibaba.graphscope.common.ir.rex.RexPermuteGraphShuttle;
 import com.alibaba.graphscope.common.ir.rex.RexVariableAliasCollector;
 import com.alibaba.graphscope.common.ir.tools.GraphBuilder;
-import com.alibaba.graphscope.common.ir.tools.config.*;
+import com.alibaba.graphscope.common.ir.tools.config.ExpandConfig;
+import com.alibaba.graphscope.common.ir.tools.config.GetVConfig;
+import com.alibaba.graphscope.common.ir.tools.config.LabelConfig;
+import com.alibaba.graphscope.common.ir.tools.config.SourceConfig;
 import com.alibaba.graphscope.common.ir.type.GraphNameOrId;
 import com.alibaba.graphscope.common.ir.type.GraphProperty;
 import com.alibaba.graphscope.common.ir.type.GraphSchemaType;
@@ -447,7 +450,8 @@ public TrimResult trimFields(GraphLogicalPathExpand pathExpand, UsedFields field
                         pathExpand.getFetch(),
                         pathExpand.getResultOpt(),
                         pathExpand.getPathOpt(),
-                        pathExpand.getAliasName());
+                        pathExpand.getAliasName(),
+                        pathExpand.getStartAlias());
         return result(newPathExpand, mapping, pathExpand);
     }
 

interactive_engine/compiler/src/main/java/com/alibaba/graphscope/common/ir/rel/graph/AbstractBindableTableScan.java

@@ -16,6 +16,7 @@
 
 package com.alibaba.graphscope.common.ir.rel.graph;
 
+import com.alibaba.graphscope.common.ir.rel.type.AliasNameWithId;
 import com.alibaba.graphscope.common.ir.rel.type.TableConfig;
 import com.alibaba.graphscope.common.ir.tools.AliasInference;
 import com.alibaba.graphscope.common.ir.type.GraphSchemaType;
@@ -55,12 +56,15 @@ public abstract class AbstractBindableTableScan extends TableScan {
 
     protected final int aliasId;
 
+    protected final AliasNameWithId startAlias;
+
     protected AbstractBindableTableScan(
             GraphOptCluster cluster,
             List<RelHint> hints,
             @Nullable RelNode input,
             TableConfig tableConfig,
-            @Nullable String aliasName) {
+            @Nullable String aliasName,
+            AliasNameWithId startAlias) {
         super(
                 cluster,
                 RelTraitSet.createEmpty(),
@@ -74,14 +78,15 @@ protected AbstractBindableTableScan(
                 AliasInference.inferDefault(
                         aliasName, AliasInference.getUniqueAliasList(input, true));
         this.aliasId = cluster.getIdGenerator().generate(this.aliasName);
+        this.startAlias = Objects.requireNonNull(startAlias);
     }
 
     protected AbstractBindableTableScan(
             GraphOptCluster cluster,
             List<RelHint> hints,
             TableConfig tableConfig,
             String aliasName) {
-        this(cluster, hints, null, tableConfig, aliasName);
+        this(cluster, hints, null, tableConfig, aliasName, AliasNameWithId.DEFAULT);
     }
 
     @Override
@@ -132,6 +137,10 @@ public RelWriter explainTerms(RelWriter pw) {
         return pw.itemIf("input", input, !Objects.isNull(input))
                 .item("tableConfig", tableConfig)
                 .item("alias", AliasInference.SIMPLE_NAME(getAliasName()))
+                .itemIf(
+                        "startAlias",
+                        startAlias.getAliasName(),
+                        startAlias.getAliasName() != AliasInference.DEFAULT_NAME)
                 .itemIf("fusedProject", project, !ObjectUtils.isEmpty(project))
                 .itemIf("fusedFilter", filters, !ObjectUtils.isEmpty(filters));
     }
@@ -156,4 +165,8 @@ public void setFilters(ImmutableList<RexNode> filters) {
     public @Nullable ImmutableList<RexNode> getFilters() {
         return filters;
     }
+
+    public AliasNameWithId getStartAlias() {
+        return startAlias;
+    }
 }

interactive_engine/compiler/src/main/java/com/alibaba/graphscope/common/ir/rel/graph/GraphLogicalExpand.java

@@ -16,6 +16,7 @@
 
 package com.alibaba.graphscope.common.ir.rel.graph;
 
+import com.alibaba.graphscope.common.ir.rel.type.AliasNameWithId;
 import com.alibaba.graphscope.common.ir.rel.type.TableConfig;
 import com.alibaba.graphscope.common.ir.tools.config.GraphOpt;
 
@@ -37,8 +38,9 @@ protected GraphLogicalExpand(
             RelNode input,
             GraphOpt.Expand opt,
             TableConfig tableConfig,
-            @Nullable String alias) {
-        super(cluster, hints, input, tableConfig, alias);
+            @Nullable String alias,
+            AliasNameWithId startAlias) {
+        super(cluster, hints, input, tableConfig, alias, startAlias);
         this.opt = opt;
     }
 
@@ -48,8 +50,9 @@ public static GraphLogicalExpand create(
             RelNode input,
             GraphOpt.Expand opt,
             TableConfig tableConfig,
-            @Nullable String alias) {
-        return new GraphLogicalExpand(cluster, hints, input, opt, tableConfig, alias);
+            @Nullable String alias,
+            AliasNameWithId startAlias) {
+        return new GraphLogicalExpand(cluster, hints, input, opt, tableConfig, alias, startAlias);
     }
 
     public GraphOpt.Expand getOpt() {
@@ -69,6 +72,7 @@ public GraphLogicalExpand copy(RelTraitSet traitSet, List<RelNode> inputs) {
                 inputs.get(0),
                 this.getOpt(),
                 this.tableConfig,
-                this.getAliasName());
+                this.getAliasName(),
+                this.getStartAlias());
     }
 }

interactive_engine/compiler/src/main/java/com/alibaba/graphscope/common/ir/rel/graph/GraphLogicalGetV.java

@@ -16,6 +16,7 @@
 
 package com.alibaba.graphscope.common.ir.rel.graph;
 
+import com.alibaba.graphscope.common.ir.rel.type.AliasNameWithId;
 import com.alibaba.graphscope.common.ir.rel.type.TableConfig;
 import com.alibaba.graphscope.common.ir.tools.config.GraphOpt;
 
@@ -37,8 +38,9 @@ protected GraphLogicalGetV(
             RelNode input,
             GraphOpt.GetV opt,
             TableConfig tableConfig,
-            @Nullable String alias) {
-        super(cluster, hints, input, tableConfig, alias);
+            @Nullable String alias,
+            AliasNameWithId startAlias) {
+        super(cluster, hints, input, tableConfig, alias, startAlias);
         this.opt = opt;
     }
 
@@ -48,8 +50,9 @@ public static GraphLogicalGetV create(
             RelNode input,
             GraphOpt.GetV opt,
             TableConfig tableConfig,
-            @Nullable String alias) {
-        return new GraphLogicalGetV(cluster, hints, input, opt, tableConfig, alias);
+            @Nullable String alias,
+            AliasNameWithId startAlias) {
+        return new GraphLogicalGetV(cluster, hints, input, opt, tableConfig, alias, startAlias);
     }
 
     public GraphOpt.GetV getOpt() {
@@ -69,6 +72,7 @@ public GraphLogicalGetV copy(RelTraitSet traitSet, List<RelNode> inputs) {
                 inputs.get(0),
                 this.getOpt(),
                 this.tableConfig,
-                this.getAliasName());
+                this.getAliasName(),
+                this.getStartAlias());
     }
 }

interactive_engine/compiler/src/main/java/com/alibaba/graphscope/common/ir/rel/graph/GraphLogicalPathExpand.java

@@ -16,6 +16,7 @@
 
 package com.alibaba.graphscope.common.ir.rel.graph;
 
+import com.alibaba.graphscope.common.ir.rel.type.AliasNameWithId;
 import com.alibaba.graphscope.common.ir.tools.AliasInference;
 import com.alibaba.graphscope.common.ir.tools.config.GraphOpt;
 import com.alibaba.graphscope.common.ir.type.GraphPathType;
@@ -52,6 +53,8 @@ public class GraphLogicalPathExpand extends SingleRel {
 
     private final int aliasId;
 
+    private final AliasNameWithId startAlias;
+
     protected GraphLogicalPathExpand(
             GraphOptCluster cluster,
             @Nullable List<RelHint> hints,
@@ -62,7 +65,8 @@ protected GraphLogicalPathExpand(
             @Nullable RexNode fetch,
             GraphOpt.PathExpandResult resultOpt,
             GraphOpt.PathExpandPath pathOpt,
-            @Nullable String aliasName) {
+            @Nullable String aliasName,
+            AliasNameWithId startAlias) {
         super(cluster, RelTraitSet.createEmpty(), input);
         this.expand = Objects.requireNonNull(expand);
         this.getV = Objects.requireNonNull(getV);
@@ -74,6 +78,7 @@ protected GraphLogicalPathExpand(
                 AliasInference.inferDefault(
                         aliasName, AliasInference.getUniqueAliasList(input, true));
         this.aliasId = cluster.getIdGenerator().generate(this.aliasName);
+        this.startAlias = Objects.requireNonNull(startAlias);
     }
 
     public static GraphLogicalPathExpand create(
@@ -86,9 +91,20 @@ public static GraphLogicalPathExpand create(
             @Nullable RexNode fetch,
             GraphOpt.PathExpandResult resultOpt,
             GraphOpt.PathExpandPath pathOpt,
-            String aliasName) {
+            String aliasName,
+            AliasNameWithId startAlias) {
         return new GraphLogicalPathExpand(
-                cluster, hints, input, expand, getV, offset, fetch, resultOpt, pathOpt, aliasName);
+                cluster,
+                hints,
+                input,
+                expand,
+                getV,
+                offset,
+                fetch,
+                resultOpt,
+                pathOpt,
+                aliasName,
+                startAlias);
     }
 
     @Override
@@ -100,7 +116,11 @@ public RelWriter explainTerms(RelWriter pw) {
                 .itemIf("fetch", fetch, fetch != null)
                 .item("path_opt", getPathOpt())
                 .item("result_opt", getResultOpt())
-                .item("alias", AliasInference.SIMPLE_NAME(getAliasName()));
+                .item("alias", AliasInference.SIMPLE_NAME(getAliasName()))
+                .itemIf(
+                        "start_alias",
+                        startAlias.getAliasName(),
+                        startAlias.getAliasName() != AliasInference.DEFAULT_NAME);
     }
 
     public String getAliasName() {
@@ -135,6 +155,10 @@ public RelNode getGetV() {
         return fetch;
     }
 
+    public AliasNameWithId getStartAlias() {
+        return startAlias;
+    }
+
     @Override
     protected RelDataType deriveRowType() {
         ObjectUtils.requireNonEmpty(

interactive_engine/compiler/src/main/java/com/alibaba/graphscope/common/ir/rel/type/AliasNameWithId.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2020 Alibaba Group Holding Limited.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.alibaba.graphscope.common.ir.rel.type;
+
+import com.alibaba.graphscope.common.ir.tools.AliasInference;
+
+public class AliasNameWithId {
+    public static final AliasNameWithId DEFAULT =
+            new AliasNameWithId(AliasInference.DEFAULT_NAME, AliasInference.DEFAULT_ID);
+
+    private final String aliasName;
+    private final int aliasId;
+
+    public AliasNameWithId(String aliasName, int aliasId) {
+        this.aliasName = aliasName;
+        this.aliasId = aliasId;
+    }
+
+    public String getAliasName() {
+        return aliasName;
+    }
+
+    public int getAliasId() {
+        return aliasId;
+    }
+}

interactive_engine/compiler/src/main/java/com/alibaba/graphscope/common/ir/runtime/ffi/RelToFfiConverter.java

@@ -108,6 +108,11 @@ public RelNode visit(GraphLogicalExpand expand) {
         if (expand.getAliasId() != AliasInference.DEFAULT_ID) {
             checkFfiResult(LIB.setEdgexpdAlias(ptrExpand, ArgUtils.asAlias(expand.getAliasId())));
         }
+        if (expand.getStartAlias().getAliasId() != AliasInference.DEFAULT_ID) {
+            checkFfiResult(
+                    LIB.setEdgexpdVtag(
+                            ptrExpand, ArgUtils.asNameOrId(expand.getStartAlias().getAliasId())));
+        }
         checkFfiResult(
                 LIB.setEdgexpdMeta(
                         ptrExpand,
@@ -149,6 +154,11 @@ public RelNode visit(GraphLogicalGetV getV) {
         if (getV.getAliasId() != AliasInference.DEFAULT_ID) {
             checkFfiResult(LIB.setGetvAlias(ptrGetV, ArgUtils.asAlias(getV.getAliasId())));
         }
+        if (getV.getStartAlias().getAliasId() != AliasInference.DEFAULT_ID) {
+            checkFfiResult(
+                    LIB.setGetvTag(
+                            ptrGetV, ArgUtils.asNameOrId(getV.getStartAlias().getAliasId())));
+        }
         checkFfiResult(
                 LIB.setGetvMeta(
                         ptrGetV,
@@ -175,6 +185,11 @@ public RelNode visit(GraphLogicalPathExpand pxd) {
         if (pxd.getAliasId() != AliasInference.DEFAULT_ID) {
             checkFfiResult(LIB.setPathxpdAlias(ptrPxd, ArgUtils.asAlias(pxd.getAliasId())));
         }
+        if (pxd.getStartAlias().getAliasId() != AliasInference.DEFAULT_ID) {
+            checkFfiResult(
+                    LIB.setPathxpdTag(
+                            ptrPxd, ArgUtils.asNameOrId(pxd.getStartAlias().getAliasId())));
+        }
         return new PhysicalNode(pxd, ptrPxd);
     }