pgwire/
pg_response.rs

1// Copyright 2025 RisingWave Labs
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15use std::fmt::Formatter;
16use std::pin::Pin;
17
18use futures::{Future, FutureExt, Stream, StreamExt};
19use risingwave_sqlparser::ast::Statement;
20
21use crate::error::PsqlError;
22use crate::pg_field_descriptor::PgFieldDescriptor;
23use crate::pg_protocol::ParameterStatus;
24use crate::pg_server::BoxedError;
25use crate::types::{Format, Row};
26
27pub type RowSet = Vec<Row>;
28pub type RowSetResult = Result<RowSet, BoxedError>;
29
30pub trait ValuesStream = Stream<Item = RowSetResult> + Unpin + Send;
31
32#[derive(Copy, Clone, Debug, Eq, PartialEq)]
33#[expect(non_camel_case_types, clippy::upper_case_acronyms)]
34pub enum StatementType {
35    INSERT,
36    INSERT_RETURNING,
37    DELETE,
38    DELETE_RETURNING,
39    UPDATE,
40    UPDATE_RETURNING,
41    SELECT,
42    MOVE,
43    FETCH,
44    COPY,
45    EXPLAIN,
46    CLOSE_CURSOR,
47    CREATE_TABLE,
48    CREATE_MATERIALIZED_VIEW,
49    CREATE_VIEW,
50    CREATE_SOURCE,
51    CREATE_SINK,
52    CREATE_SUBSCRIPTION,
53    CREATE_DATABASE,
54    CREATE_SCHEMA,
55    CREATE_USER,
56    CREATE_INDEX,
57    CREATE_AGGREGATE,
58    CREATE_FUNCTION,
59    CREATE_CONNECTION,
60    CREATE_SECRET,
61    COMMENT,
62    DECLARE_CURSOR,
63    DESCRIBE,
64    GRANT_PRIVILEGE,
65    DISCARD,
66    DROP_TABLE,
67    DROP_MATERIALIZED_VIEW,
68    DROP_VIEW,
69    DROP_INDEX,
70    DROP_FUNCTION,
71    DROP_AGGREGATE,
72    DROP_SOURCE,
73    DROP_SINK,
74    DROP_SUBSCRIPTION,
75    DROP_SCHEMA,
76    DROP_DATABASE,
77    DROP_USER,
78    DROP_CONNECTION,
79    DROP_SECRET,
80    ALTER_DATABASE,
81    ALTER_DEFAULT_PRIVILEGES,
82    ALTER_SCHEMA,
83    ALTER_INDEX,
84    ALTER_VIEW,
85    ALTER_TABLE,
86    ALTER_MATERIALIZED_VIEW,
87    ALTER_SINK,
88    ALTER_SUBSCRIPTION,
89    ALTER_SOURCE,
90    ALTER_FUNCTION,
91    ALTER_CONNECTION,
92    ALTER_SYSTEM,
93    ALTER_SECRET,
94    ALTER_FRAGMENT,
95    REVOKE_PRIVILEGE,
96    // Introduce ORDER_BY statement type cuz Calcite unvalidated AST has SqlKind.ORDER_BY. Note
97    // that Statement Type is not designed to be one to one mapping with SqlKind.
98    ORDER_BY,
99    SET_VARIABLE,
100    SHOW_VARIABLE,
101    SHOW_COMMAND,
102    START_TRANSACTION,
103    UPDATE_USER,
104    ABORT,
105    FLUSH,
106    REFRESH_TABLE,
107    OTHER,
108    // EMPTY is used when query statement is empty (e.g. ";").
109    EMPTY,
110    BEGIN,
111    COMMIT,
112    ROLLBACK,
113    SET_TRANSACTION,
114    CANCEL_COMMAND,
115    FETCH_CURSOR,
116    WAIT,
117    KILL,
118    RECOVER,
119    USE,
120    PREPARE,
121    DEALLOCATE,
122    VACUUM,
123}
124
125impl std::fmt::Display for StatementType {
126    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
127        write!(f, "{:?}", self)
128    }
129}
130
131pub trait Callback = Future<Output = Result<(), BoxedError>> + Send;
132
133pub type BoxedCallback = Pin<Box<dyn Callback>>;
134
135pub struct PgResponse<VS> {
136    stmt_type: StatementType,
137    is_copy_query_to_stdout: bool,
138
139    // row count of affected row. Used for INSERT, UPDATE, DELETE, COPY, and other statements that
140    // don't return rows.
141    row_cnt: Option<i32>,
142    // Used for INSERT, UPDATE, DELETE to specify the format of the affected row count.
143    row_cnt_format: Option<Format>,
144    notices: Vec<String>,
145    values_stream: Option<VS>,
146    callback: Option<BoxedCallback>,
147    row_desc: Vec<PgFieldDescriptor>,
148    status: ParameterStatus,
149}
150
151pub struct PgResponseBuilder<VS> {
152    stmt_type: StatementType,
153    // row count of affected row. Used for INSERT, UPDATE, DELETE, COPY, and other statements that
154    // don't return rows.
155    row_cnt: Option<i32>,
156    // Used for INSERT, UPDATE, DELETE to specify the format of the affected row count.
157    row_cnt_format: Option<Format>,
158    notices: Vec<String>,
159    values_stream: Option<VS>,
160    callback: Option<BoxedCallback>,
161    row_desc: Vec<PgFieldDescriptor>,
162    status: ParameterStatus,
163}
164
165impl<VS> From<PgResponseBuilder<VS>> for PgResponse<VS> {
166    fn from(builder: PgResponseBuilder<VS>) -> Self {
167        Self {
168            stmt_type: builder.stmt_type,
169            is_copy_query_to_stdout: false, // set a false from builder, alter later
170            row_cnt: builder.row_cnt,
171            row_cnt_format: builder.row_cnt_format,
172            notices: builder.notices,
173            values_stream: builder.values_stream,
174            callback: builder.callback,
175            row_desc: builder.row_desc,
176            status: builder.status,
177        }
178    }
179}
180
181impl<VS> PgResponseBuilder<VS> {
182    pub fn empty(stmt_type: StatementType) -> Self {
183        let row_cnt = if stmt_type.is_query() { None } else { Some(0) };
184        Self {
185            stmt_type,
186            row_cnt,
187            row_cnt_format: None,
188            notices: vec![],
189            values_stream: None,
190            callback: None,
191            row_desc: vec![],
192            status: Default::default(),
193        }
194    }
195
196    pub fn row_cnt(self, row_cnt: i32) -> Self {
197        Self {
198            row_cnt: Some(row_cnt),
199            ..self
200        }
201    }
202
203    pub fn row_cnt_opt(self, row_cnt: Option<i32>) -> Self {
204        Self { row_cnt, ..self }
205    }
206
207    pub fn row_cnt_format_opt(self, row_cnt_format: Option<Format>) -> Self {
208        Self {
209            row_cnt_format,
210            ..self
211        }
212    }
213
214    pub fn values(self, values_stream: VS, row_desc: Vec<PgFieldDescriptor>) -> Self {
215        Self {
216            values_stream: Some(values_stream),
217            row_desc,
218            ..self
219        }
220    }
221
222    pub fn callback(self, callback: impl Callback + 'static) -> Self {
223        Self {
224            callback: Some(callback.boxed()),
225            ..self
226        }
227    }
228
229    pub fn notice(self, notice: impl ToString) -> Self {
230        let mut notices = self.notices;
231        notices.push(notice.to_string());
232        Self { notices, ..self }
233    }
234
235    pub fn status(self, status: ParameterStatus) -> Self {
236        Self { status, ..self }
237    }
238}
239
240impl<VS> std::fmt::Debug for PgResponse<VS> {
241    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
242        f.debug_struct("PgResponse")
243            .field("stmt_type", &self.stmt_type)
244            .field("row_cnt", &self.row_cnt)
245            .field("notices", &self.notices)
246            .field("row_desc", &self.row_desc)
247            .finish()
248    }
249}
250
251impl StatementType {
252    pub fn infer_from_statement(stmt: &Statement) -> Result<Self, String> {
253        match stmt {
254            Statement::Query(_) => Ok(StatementType::SELECT),
255            Statement::Insert { returning, .. } => {
256                if returning.is_empty() {
257                    Ok(StatementType::INSERT)
258                } else {
259                    Ok(StatementType::INSERT_RETURNING)
260                }
261            }
262            Statement::Delete { returning, .. } => {
263                if returning.is_empty() {
264                    Ok(StatementType::DELETE)
265                } else {
266                    Ok(StatementType::DELETE_RETURNING)
267                }
268            }
269            Statement::Update { returning, .. } => {
270                if returning.is_empty() {
271                    Ok(StatementType::UPDATE)
272                } else {
273                    Ok(StatementType::UPDATE_RETURNING)
274                }
275            }
276            Statement::Copy { .. } => Ok(StatementType::COPY),
277            Statement::CreateTable { .. } => Ok(StatementType::CREATE_TABLE),
278            Statement::CreateIndex { .. } => Ok(StatementType::CREATE_INDEX),
279            Statement::CreateSchema { .. } => Ok(StatementType::CREATE_SCHEMA),
280            Statement::CreateSource { .. } => Ok(StatementType::CREATE_SOURCE),
281            Statement::CreateSink { .. } => Ok(StatementType::CREATE_SINK),
282            Statement::CreateFunction { .. } => Ok(StatementType::CREATE_FUNCTION),
283            Statement::CreateDatabase { .. } => Ok(StatementType::CREATE_DATABASE),
284            Statement::CreateUser { .. } => Ok(StatementType::CREATE_USER),
285            Statement::CreateView { materialized, .. } => {
286                if *materialized {
287                    Ok(StatementType::CREATE_MATERIALIZED_VIEW)
288                } else {
289                    Ok(StatementType::CREATE_VIEW)
290                }
291            }
292            Statement::AlterTable { .. } => Ok(StatementType::ALTER_TABLE),
293            Statement::AlterSystem { .. } => Ok(StatementType::ALTER_SYSTEM),
294            Statement::AlterFragment { .. } => Ok(StatementType::ALTER_FRAGMENT),
295            Statement::DropFunction { .. } => Ok(StatementType::DROP_FUNCTION),
296            Statement::Discard(..) => Ok(StatementType::DISCARD),
297            Statement::SetVariable { .. } => Ok(StatementType::SET_VARIABLE),
298            Statement::ShowVariable { .. } => Ok(StatementType::SHOW_VARIABLE),
299            Statement::StartTransaction { .. } => Ok(StatementType::START_TRANSACTION),
300            Statement::Begin { .. } => Ok(StatementType::BEGIN),
301            Statement::Abort => Ok(StatementType::ABORT),
302            Statement::Commit { .. } => Ok(StatementType::COMMIT),
303            Statement::Rollback { .. } => Ok(StatementType::ROLLBACK),
304            Statement::Grant { .. } => Ok(StatementType::GRANT_PRIVILEGE),
305            Statement::Revoke { .. } => Ok(StatementType::REVOKE_PRIVILEGE),
306            Statement::Describe { .. } => Ok(StatementType::DESCRIBE),
307            Statement::ShowCreateObject { .. } | Statement::ShowObjects { .. } => {
308                Ok(StatementType::SHOW_COMMAND)
309            }
310            Statement::Drop(stmt) => match stmt.object_type {
311                risingwave_sqlparser::ast::ObjectType::Table => Ok(StatementType::DROP_TABLE),
312                risingwave_sqlparser::ast::ObjectType::View => Ok(StatementType::DROP_VIEW),
313                risingwave_sqlparser::ast::ObjectType::MaterializedView => {
314                    Ok(StatementType::DROP_MATERIALIZED_VIEW)
315                }
316                risingwave_sqlparser::ast::ObjectType::Index => Ok(StatementType::DROP_INDEX),
317                risingwave_sqlparser::ast::ObjectType::Schema => Ok(StatementType::DROP_SCHEMA),
318                risingwave_sqlparser::ast::ObjectType::Source => Ok(StatementType::DROP_SOURCE),
319                risingwave_sqlparser::ast::ObjectType::Sink => Ok(StatementType::DROP_SINK),
320                risingwave_sqlparser::ast::ObjectType::Database => Ok(StatementType::DROP_DATABASE),
321                risingwave_sqlparser::ast::ObjectType::User => Ok(StatementType::DROP_USER),
322                risingwave_sqlparser::ast::ObjectType::Connection => {
323                    Ok(StatementType::DROP_CONNECTION)
324                }
325                risingwave_sqlparser::ast::ObjectType::Secret => Ok(StatementType::DROP_SECRET),
326                risingwave_sqlparser::ast::ObjectType::Subscription => {
327                    Ok(StatementType::DROP_SUBSCRIPTION)
328                }
329            },
330            Statement::Explain { .. } => Ok(StatementType::EXPLAIN),
331            Statement::DeclareCursor { .. } => Ok(StatementType::DECLARE_CURSOR),
332            Statement::FetchCursor { .. } => Ok(StatementType::FETCH_CURSOR),
333            Statement::CloseCursor { .. } => Ok(StatementType::CLOSE_CURSOR),
334            Statement::Flush => Ok(StatementType::FLUSH),
335            Statement::Wait => Ok(StatementType::WAIT),
336            Statement::Use { .. } => Ok(StatementType::USE),
337            Statement::Vacuum { .. } => Ok(StatementType::VACUUM),
338            _ => Err("unsupported statement type".to_owned()),
339        }
340    }
341
342    pub fn is_command(&self) -> bool {
343        matches!(
344            self,
345            StatementType::INSERT
346                | StatementType::DELETE
347                | StatementType::UPDATE
348                | StatementType::MOVE
349                | StatementType::COPY
350                | StatementType::FETCH
351                | StatementType::SELECT
352                | StatementType::INSERT_RETURNING
353                | StatementType::DELETE_RETURNING
354                | StatementType::UPDATE_RETURNING
355        )
356    }
357
358    pub fn is_dml(&self) -> bool {
359        matches!(
360            self,
361            StatementType::INSERT
362                | StatementType::DELETE
363                | StatementType::UPDATE
364                | StatementType::INSERT_RETURNING
365                | StatementType::DELETE_RETURNING
366                | StatementType::UPDATE_RETURNING
367        )
368    }
369
370    pub fn is_query(&self) -> bool {
371        matches!(
372            self,
373            StatementType::SELECT
374                | StatementType::EXPLAIN
375                | StatementType::SHOW_COMMAND
376                | StatementType::SHOW_VARIABLE
377                | StatementType::DESCRIBE
378                | StatementType::INSERT_RETURNING
379                | StatementType::DELETE_RETURNING
380                | StatementType::UPDATE_RETURNING
381                | StatementType::CANCEL_COMMAND
382                | StatementType::FETCH_CURSOR
383        )
384    }
385
386    pub fn is_returning(&self) -> bool {
387        matches!(
388            self,
389            StatementType::INSERT_RETURNING
390                | StatementType::DELETE_RETURNING
391                | StatementType::UPDATE_RETURNING
392        )
393    }
394}
395
396impl<VS> PgResponse<VS>
397where
398    VS: ValuesStream,
399{
400    pub fn builder(stmt_type: StatementType) -> PgResponseBuilder<VS> {
401        PgResponseBuilder::empty(stmt_type)
402    }
403
404    pub fn empty_result(stmt_type: StatementType) -> Self {
405        PgResponseBuilder::empty(stmt_type).into()
406    }
407
408    pub fn into_copy_query_to_stdout(mut self) -> Self {
409        self.is_copy_query_to_stdout = true;
410        self.stmt_type = StatementType::COPY;
411        self
412    }
413
414    pub fn stmt_type(&self) -> StatementType {
415        self.stmt_type
416    }
417
418    pub fn notices(&self) -> &[String] {
419        &self.notices
420    }
421
422    pub fn status(&self) -> &ParameterStatus {
423        &self.status
424    }
425
426    pub fn affected_rows_cnt(&self) -> Option<i32> {
427        self.row_cnt
428    }
429
430    pub fn row_cnt_format(&self) -> Option<Format> {
431        self.row_cnt_format
432    }
433
434    pub fn is_query(&self) -> bool {
435        self.stmt_type.is_query()
436    }
437
438    pub fn is_empty(&self) -> bool {
439        self.stmt_type == StatementType::EMPTY
440    }
441
442    pub fn is_copy_query_to_stdout(&self) -> bool {
443        self.is_copy_query_to_stdout
444    }
445
446    pub fn row_desc(&self) -> &[PgFieldDescriptor] {
447        &self.row_desc
448    }
449
450    pub fn values_stream(&mut self) -> &mut VS {
451        self.values_stream.as_mut().expect("no values stream")
452    }
453
454    /// Run the callback if there is one.
455    ///
456    /// This should only be called after the values stream has been exhausted. Multiple calls to
457    /// this function will be no-ops.
458    pub async fn run_callback(&mut self) -> Result<(), PsqlError> {
459        // Check if the stream is exhausted.
460        if let Some(values_stream) = &mut self.values_stream {
461            assert!(values_stream.next().await.is_none());
462        }
463
464        if let Some(callback) = self.callback.take() {
465            callback.await.map_err(PsqlError::SimpleQueryError)?;
466        }
467        Ok(())
468    }
469}
pgwire/pg_response.rs

pgwire/
pg_response.rs
