support describe space

src/graph/CMakeLists.txt

@@ -30,6 +30,7 @@ add_library(
     RemoveHostsExecutor.cpp
     CreateSpaceExecutor.cpp
     DropSpaceExecutor.cpp
+    DescribeSpaceExecutor.cpp
     ShowExecutor.cpp
     YieldExecutor.cpp
     mock/PropertiesSchema.cpp

src/graph/DescribeSpaceExecutor.cpp

@@ -0,0 +1,53 @@
+/* Copyright (c) 2018 - present, VE Software Inc. All rights reserved
+ *
+ * This source code is licensed under Apache 2.0 License
+ *  (found in the LICENSE.Apache file in the root directory)
+ */
+
+#include "base/Base.h"
+#include "graph/DescribeSpaceExecutor.h"
+#include "meta/SchemaManager.h"
+
+namespace nebula {
+namespace graph {
+
+DescribeSpaceExecutor::DescribeSpaceExecutor(Sentence *sentence,
+                                             ExecutionContext *ectx) : Executor(ectx) {
+    sentence_ = static_cast<DescribeSpaceSentence*>(sentence);
+}
+
+Status DescribeSpaceExecutor::prepare() {
+    return checkIfGraphSpaceChosen();
+}
+
+void DescribeSpaceExecutor::execute() {
+    auto spaceId = ectx()->rctx()->session()->space();
+    auto future = ectx()->getMetaClient()->getSpace(spaceId);
+    auto *runner = ectx()->rctx()->runner();
+
+    auto cb = [this] (auto &&resp) {
+        if (!resp.ok()) {
+            DCHECK(onError_);
+            onError_(std::move(resp).status());
+            return;
+        }
+        DCHECK(onFinish_);
+        onFinish_();
+    };
+
+    auto error = [this] (auto &&e) {
+        LOG(ERROR) << "Exception caught: " << e.what();
+        DCHECK(onError_);
+        onError_(Status::Error("Internal error"));
+        return;
+    };
+
+    std::move(future).via(runner).thenValue(cb).thenError(error);
+}
+
+void DescribeSpaceExecutor::setupResponse(cpp2::ExecutionResponse &resp) {
+    resp = std::move(*resp_);
+}
+
+}   // namespace graph
+}   // namespace nebula

src/graph/DescribeSpaceExecutor.h

@@ -0,0 +1,39 @@
+/* Copyright (c) 2018 - present, VE Software Inc. All rights reserved
+ *
+ * This source code is licensed under Apache 2.0 License
+ *  (found in the LICENSE.Apache file in the root directory)
+ */
+
+#ifndef GRAPH_DESCRIBESPACEEXECUTOR_H_
+#define GRAPH_DESCRIBESPACEEXECUTOR_H_
+
+#include "base/Base.h"
+#include "graph/Executor.h"
+
+namespace nebula {
+namespace graph {
+
+class DescribeSpaceExecutor final : public Executor {
+public:
+    DescribeSpaceExecutor(Sentence *sentence, ExecutionContext *ectx);
+
+    const char* name() const override {
+        return "DescribeSpaceExecutor";
+    }
+
+    Status MUST_USE_RESULT prepare() override;
+
+    void execute() override;
+
+    void setupResponse(cpp2::ExecutionResponse &resp) override;
+
+private:
+    DescribeSpaceExecutor                      *sentence_{nullptr};
+    std::string                                *tag_{nullptr};
+    std::unique_ptr<cpp2::ExecutionResponse>    resp_;
+};
+
+}   // namespace graph
+}   // namespace nebula
+
+#endif  // GRAPH_DESCRIBESPACEEXECUTOR_H_

src/graph/Executor.cpp

@@ -26,6 +26,7 @@
 #include "graph/AddHostsExecutor.h"
 #include "graph/RemoveHostsExecutor.h"
 #include "graph/CreateSpaceExecutor.h"
+#include "graph/DescribeSpaceExecutor.h"
 #include "graph/DropSpaceExecutor.h"
 #include "graph/YieldExecutor.h"
 
@@ -87,6 +88,9 @@ std::unique_ptr<Executor> Executor::makeExecutor(Sentence *sentence) {
         case Sentence::Kind::kDropSpace:
             executor = std::make_unique<DropSpaceExecutor>(sentence, ectx());
             break;
+        case Sentence::Kind::kDescribeSpace:
+            executor = std::make_unique<DescribeSpaceExecutor>(sentence, ectx());
+            break;
         case Sentence::Kind::kYield:
             executor = std::make_unique<YieldExecutor>(sentence, ectx());
             break;

src/graph/test/SchemaTest.cpp

@@ -58,6 +58,12 @@ TEST_F(SchemaTest, metaCommunication) {
         auto code = client->execute(query, resp);
         ASSERT_EQ(cpp2::ErrorCode::SUCCEEDED, code);
     }
+    {
+        cpp2::ExecutionResponse resp;
+        std::string query = "DESCRIBE SPACE default_space";
+        auto code = client->execute(query, resp);
+        ASSERT_EQ(cpp2::ErrorCode::SUCCEEDED, code);
+    }
     sleep(FLAGS_load_data_interval_second + 1);
     {
         cpp2::ExecutionResponse resp;

src/interface/meta.thrift

@@ -53,6 +53,13 @@ struct IdName {
     2: string name,
 }
 
+struct SpaceItem {
+    1: common.GraphSpaceID  space_id,
+    2: string               space_name,
+    3: i32                  partition_num,
+    4: i32                  replica_factor,
+}
+
 struct Pair {
     1: string key,
     2: string value,
@@ -111,9 +118,8 @@ struct GetSpaceReq {
 }
 
 struct GetSpaceResp {
-    1: IdName space,
-    2: i32    parts_num,
-    3: i32    replica_factor,
+    1: ErrorCode   code,
+    2: SpaceItem   item,
 }
 
 // Tags related operations

src/meta/client/MetaClient.cpp

@@ -252,6 +252,16 @@ folly::Future<StatusOr<std::vector<SpaceIdName>>> MetaClient::listSpaces() {
                 });
 }
 
+folly::Future<StatusOr<cpp2::SpaceItem>>
+MetaClient::getSpace(GraphSpaceID spaceId) {
+    cpp2::GetSpaceReq req;
+    req.set_space_id(spaceId);
+    return  getResponse(std::move(req), [] (auto client, auto request) {
+                    return client->future_getSpace(request);
+                }, [] (cpp2::GetSpaceResp&& resp) -> decltype(auto) {
+                    return std::move(resp).get_item();
+                });
+}
 
 folly::Future<StatusOr<bool>> MetaClient::dropSpace(std::string name) {
     cpp2::DropSpaceReq req;

src/meta/client/MetaClient.h

@@ -79,6 +79,9 @@ class MetaClient {
     folly::Future<StatusOr<std::vector<SpaceIdName>>>
     listSpaces();
 
+    folly::Future<StatusOr<cpp2::SpaceItem>>
+    getSpace(GraphSpaceID spaceId);
+
     folly::Future<StatusOr<bool>>
     dropSpace(std::string name);
 

src/parser/AdminSentences.cpp

@@ -99,4 +99,12 @@ std::string DropSpaceSentence::toString() const {
     return buf;
 }
 
+std::string DescribeSpaceSentence::toString() const {
+    std::string buf;
+    buf.reserve(256);
+    buf += "DESCRIBE SPACE ";
+    buf += *spaceName_;
+    return buf;
+}
+
 }   // namespace nebula

src/parser/AdminSentences.h

@@ -6,7 +6,6 @@
 #ifndef PARSER_ADMINSENTENCES_H_
 #define PARSER_ADMINSENTENCES_H_
 
-#include "base/Base.h"
 #include "parser/Clauses.h"
 #include "parser/Sentence.h"
 #include "network/NetworkUtils.h"
@@ -234,6 +233,24 @@ class DropSpaceSentence final : public Sentence {
     std::unique_ptr<std::string>     spaceName_;
 };
 
+
+class DescribeSpaceSentence final : public Sentence {
+public:
+    explicit DescribeSpaceSentence(std::string *spaceName) {
+        spaceName_.reset(spaceName);
+        kind_ = Kind::kDescribeSpace;
+    }
+
+    std::string* spaceName() {
+        return spaceName_.get();
+    }
+
+    std::string toString() const override;
+
+private:
+    std::unique_ptr<std::string>     spaceName_;
+};
+
 }   // namespace nebula
 
 #endif  // PARSER_ADMINSENTENCES_H_

src/parser/Sentence.h

@@ -40,6 +40,7 @@ class Sentence {
         kRemoveHosts,
         kCreateSpace,
         kDropSpace,
+        kDescribeSpace,
         kYield,
     };
 

src/parser/parser.yy

@@ -136,7 +136,7 @@ class GraphScanner;
 %type <sentence> traverse_sentence set_sentence piped_sentence assignment_sentence
 %type <sentence> maintain_sentence insert_vertex_sentence insert_edge_sentence
 %type <sentence> mutate_sentence update_vertex_sentence update_edge_sentence delete_vertex_sentence delete_edge_sentence
-%type <sentence> show_sentence add_hosts_sentence remove_hosts_sentence create_space_sentence
+%type <sentence> show_sentence add_hosts_sentence remove_hosts_sentence create_space_sentence describe_space_sentence
 %type <sentence> drop_space_sentence
 %type <sentence> yield_sentence
 %type <sentence> sentence
@@ -837,6 +837,12 @@ create_space_sentence
     }
     ;
 
+describe_space_sentence
+    : KW_DESCRIBE KW_SPACE LABEL {
+        $$ = new DescribeSpaceSentence($3);
+    }
+    ;
+
 space_opt_list
     : space_opt_item {
         $$ = new SpaceOptList();
@@ -888,6 +894,7 @@ maintain_sentence
     | add_hosts_sentence { $$ = $1; }
     | remove_hosts_sentence { $$ = $1; }
     | create_space_sentence { $$ = $1; }
+    | describe_space_sentence { $$ = $1; }
     | drop_space_sentence { $$ = $1; }
     | yield_sentence {
         // Now we take YIELD as a normal maintenance sentence.