pgevolve_core/parse/
statement.rs

1//! Classify a top-level `pg_query` statement node into the v0.1 whitelist.
2//!
3//! Anything outside the whitelist is rejected with [`ParseError::UnsupportedObjectKind`]
4//! so that source-loading fails loudly instead of silently dropping unsupported DDL.
5
6use pg_query::NodeEnum;
7use pg_query::protobuf;
8use pg_query::protobuf::ObjectType;
9
10use crate::parse::error::{ParseError, SourceLocation};
11
12/// One supported top-level statement kind. Each variant carries the typed protobuf
13/// message that the corresponding builder will consume.
14#[derive(Debug, Clone)]
15pub enum Statement {
16    /// `CREATE SCHEMA ...`.
17    CreateSchema(protobuf::CreateSchemaStmt),
18    /// `CREATE TABLE ...`.
19    CreateTable(protobuf::CreateStmt),
20    /// `CREATE SEQUENCE ...`.
21    CreateSequence(protobuf::CreateSeqStmt),
22    /// `CREATE [UNIQUE] INDEX ...`.
23    CreateIndex(protobuf::IndexStmt),
24    /// `ALTER TABLE ...` — only `ADD CONSTRAINT FOREIGN KEY` is allowed in source DDL.
25    AlterTable(protobuf::AlterTableStmt),
26    /// `COMMENT ON ...`.
27    Comment(protobuf::CommentStmt),
28    /// `CREATE [OR REPLACE] VIEW ...`.
29    CreateView(protobuf::ViewStmt),
30    /// `CREATE MATERIALIZED VIEW ...`.
31    CreateMaterializedView(protobuf::CreateTableAsStmt),
32    /// `CREATE TYPE ... AS ENUM (...)`.
33    CreateEnum(protobuf::CreateEnumStmt),
34    /// `CREATE DOMAIN ... AS ...`.
35    CreateDomain(protobuf::CreateDomainStmt),
36    /// `CREATE TYPE ... AS (...)` (composite).
37    CreateCompositeType(protobuf::CompositeTypeStmt),
38    /// `CREATE TYPE ... AS RANGE (...)`.
39    CreateRange(protobuf::CreateRangeStmt),
40    /// `CREATE [OR REPLACE] FUNCTION ...`.
41    CreateFunction(protobuf::CreateFunctionStmt),
42    /// `CREATE [OR REPLACE] PROCEDURE ...`.
43    CreateProcedure(protobuf::CreateFunctionStmt),
44    /// `CREATE EXTENSION ...`.
45    CreateExtension(protobuf::CreateExtensionStmt),
46    /// `CREATE [CONSTRAINT] TRIGGER ...`.
47    CreateTrigger(protobuf::CreateTrigStmt),
48    /// `ALTER TABLE parent ATTACH PARTITION child FOR VALUES ...`.
49    AlterTableAttachPartition(protobuf::AlterTableStmt),
50    /// `GRANT priv ON obj TO grantee` — object-level grant (not REVOKE, not role grant).
51    Grant(protobuf::GrantStmt),
52    /// `ALTER <kind> name OWNER TO role`.
53    AlterOwner(protobuf::AlterOwnerStmt),
54    /// `ALTER DEFAULT PRIVILEGES ... GRANT ...`.
55    AlterDefaultPrivileges(protobuf::AlterDefaultPrivilegesStmt),
56    /// `CREATE POLICY name ON table ...`.
57    CreatePolicy(protobuf::CreatePolicyStmt),
58    /// `CREATE PUBLICATION name ...`.
59    CreatePublication(protobuf::CreatePublicationStmt),
60    /// `ALTER PUBLICATION name ...`.
61    AlterPublication(protobuf::AlterPublicationStmt),
62    /// `CREATE SUBSCRIPTION name CONNECTION ... PUBLICATION ...`.
63    CreateSubscription(protobuf::CreateSubscriptionStmt),
64    /// `ALTER SUBSCRIPTION name ...`.
65    AlterSubscription(protobuf::AlterSubscriptionStmt),
66    /// `CREATE STATISTICS name … ON … FROM …`.
67    CreateStatistics(protobuf::CreateStatsStmt),
68    /// `ALTER STATISTICS name SET STATISTICS n`.
69    AlterStatistics(protobuf::AlterStatsStmt),
70    /// `CREATE COLLATION qname (provider = …, locale = …, …)`.
71    CreateCollation(protobuf::DefineStmt),
72    /// `CREATE AGGREGATE qname(args) (SFUNC = …, STYPE = …, …)`.
73    CreateAggregate(protobuf::DefineStmt),
74    /// `CREATE EVENT TRIGGER name ON event …`.
75    CreateEventTrigger(protobuf::CreateEventTrigStmt),
76    /// `ALTER EVENT TRIGGER name {ENABLE|DISABLE|ENABLE REPLICA|ENABLE ALWAYS}`.
77    AlterEventTrigger(protobuf::AlterEventTrigStmt),
78}
79
80impl Statement {
81    /// Classify a node into the supported whitelist, or return
82    /// [`ParseError::UnsupportedObjectKind`] for anything else.
83    #[allow(clippy::too_many_lines)] // one arm per supported `NodeEnum` variant; the dispatch table is the function.
84    pub fn classify(node: NodeEnum, location: SourceLocation) -> Result<Self, ParseError> {
85        match node {
86            NodeEnum::CreateSchemaStmt(s) => Ok(Self::CreateSchema(s)),
87            NodeEnum::CreateStmt(s) => Ok(Self::CreateTable(s)),
88            NodeEnum::CreateSeqStmt(s) => Ok(Self::CreateSequence(s)),
89            NodeEnum::IndexStmt(s) => Ok(Self::CreateIndex(*s)),
90            NodeEnum::AlterTableStmt(s) => {
91                if is_attach_partition_stmt(&s) {
92                    Ok(Self::AlterTableAttachPartition(s))
93                } else {
94                    Ok(Self::AlterTable(s))
95                }
96            }
97            NodeEnum::CommentStmt(s) => Ok(Self::Comment(*s)),
98            NodeEnum::ViewStmt(s) => Ok(Self::CreateView(*s)),
99            NodeEnum::CreateEnumStmt(s) => Ok(Self::CreateEnum(s)),
100            NodeEnum::CreateDomainStmt(s) => Ok(Self::CreateDomain(*s)),
101            NodeEnum::CompositeTypeStmt(s) => Ok(Self::CreateCompositeType(s)),
102            NodeEnum::CreateRangeStmt(s) => Ok(Self::CreateRange(s)),
103            NodeEnum::CreateFunctionStmt(s) => {
104                if s.is_procedure {
105                    Ok(Self::CreateProcedure(*s))
106                } else {
107                    Ok(Self::CreateFunction(*s))
108                }
109            }
110            NodeEnum::CreateExtensionStmt(s) => Ok(Self::CreateExtension(s)),
111            NodeEnum::CreateTrigStmt(s) => Ok(Self::CreateTrigger(*s)),
112            NodeEnum::GrantStmt(s) => Ok(Self::Grant(s)),
113            NodeEnum::AlterOwnerStmt(s) => Ok(Self::AlterOwner(*s)),
114            NodeEnum::AlterDefaultPrivilegesStmt(s) => Ok(Self::AlterDefaultPrivileges(s)),
115            NodeEnum::CreatePolicyStmt(s) => Ok(Self::CreatePolicy(*s)),
116            NodeEnum::CreatePublicationStmt(s) => Ok(Self::CreatePublication(s)),
117            NodeEnum::AlterPublicationStmt(s) => Ok(Self::AlterPublication(s)),
118            NodeEnum::CreateSubscriptionStmt(s) => Ok(Self::CreateSubscription(s)),
119            NodeEnum::AlterSubscriptionStmt(s) => Ok(Self::AlterSubscription(s)),
120            NodeEnum::CreateStatsStmt(s) => Ok(Self::CreateStatistics(s)),
121            NodeEnum::AlterStatsStmt(s) => Ok(Self::AlterStatistics(*s)),
122            NodeEnum::CreateEventTrigStmt(s) => Ok(Self::CreateEventTrigger(s)),
123            NodeEnum::AlterEventTrigStmt(s) => Ok(Self::AlterEventTrigger(s)),
124            NodeEnum::DefineStmt(s) => {
125                let kind = ObjectType::try_from(s.kind).unwrap_or(ObjectType::Undefined);
126                match kind {
127                    ObjectType::ObjectCollation => Ok(Self::CreateCollation(s)),
128                    ObjectType::ObjectAggregate => Ok(Self::CreateAggregate(s)),
129                    _ => Err(unsupported(location, "CREATE OPERATOR/etc.")),
130                }
131            }
132            NodeEnum::RenameStmt(s) => {
133                use pg_query::protobuf::ObjectType;
134                let rename_type =
135                    ObjectType::try_from(s.rename_type).unwrap_or(ObjectType::Undefined);
136                if matches!(rename_type, ObjectType::ObjectPublication) {
137                    return Err(ParseError::Structural {
138                        location,
139                        message: "ALTER PUBLICATION … RENAME TO is not supported in pgevolve \
140                                  (pgevolve never models renames)"
141                            .into(),
142                    });
143                }
144                if matches!(rename_type, ObjectType::ObjectSubscription) {
145                    // Recover the subscription name for the error (subname is in
146                    // RenameStmt.relation for subscriptions).
147                    let sub_name = s
148                        .relation
149                        .as_ref()
150                        .map_or_else(|| String::from("<unknown>"), |r| r.relname.clone());
151                    let id = crate::identifier::Identifier::from_unquoted(&sub_name)
152                        .unwrap_or_else(|_| {
153                            crate::identifier::Identifier::from_unquoted("subscription")
154                                .expect("static identifier")
155                        });
156                    return Err(ParseError::SubscriptionRenameNotSupported(id, location));
157                }
158                if matches!(rename_type, ObjectType::ObjectEventTrigger) {
159                    // RenameStmt for an event trigger encodes the (old) name in
160                    // `s.object` as a bare String node.
161                    let name = s
162                        .object
163                        .as_ref()
164                        .and_then(|o| o.node.as_ref())
165                        .and_then(|n| match n {
166                            NodeEnum::String(st) => Some(st.sval.clone()),
167                            _ => None,
168                        })
169                        .unwrap_or_else(|| String::from("<unknown>"));
170                    let id =
171                        crate::identifier::Identifier::from_unquoted(&name).unwrap_or_else(|_| {
172                            crate::identifier::Identifier::from_unquoted("event_trigger")
173                                .expect("static identifier")
174                        });
175                    return Err(ParseError::EventTriggerRenameNotSupported(id, location));
176                }
177                if matches!(rename_type, ObjectType::ObjectAggregate) {
178                    return Err(ParseError::Structural {
179                        location,
180                        message: "ALTER AGGREGATE … RENAME TO is not supported in pgevolve \
181                                  (pgevolve never models renames)"
182                            .into(),
183                    });
184                }
185                if matches!(rename_type, ObjectType::ObjectStatisticExt) {
186                    // RenameStmt for statistics encodes the name in `s.subname` (the
187                    // new name) and `s.relation` (the old qualified name).
188                    let schema = s
189                        .relation
190                        .as_ref()
191                        .map_or_else(String::new, |r| r.schemaname.clone());
192                    let name = s
193                        .relation
194                        .as_ref()
195                        .map_or_else(|| String::from("<unknown>"), |r| r.relname.clone());
196                    let schema_id = crate::identifier::Identifier::from_unquoted(&schema)
197                        .unwrap_or_else(|_| {
198                            crate::identifier::Identifier::from_unquoted("unknown")
199                                .expect("static identifier")
200                        });
201                    let name_id = crate::identifier::Identifier::from_unquoted(&name)
202                        .unwrap_or_else(|_| {
203                            crate::identifier::Identifier::from_unquoted("statistic")
204                                .expect("static identifier")
205                        });
206                    let qname = crate::identifier::QualifiedName::new(schema_id, name_id);
207                    return Err(ParseError::StatisticRenameNotSupported(qname, location));
208                }
209                Err(unsupported(location, "RENAME"))
210            }
211            NodeEnum::AlterPolicyStmt(_) => Err(ParseError::Structural {
212                location,
213                message: "ALTER POLICY in source is not supported — policy modifications \
214                          happen via diff; use CREATE POLICY in source"
215                    .into(),
216            }),
217            NodeEnum::DropStmt(s) => {
218                let kind = ObjectType::try_from(s.remove_type).unwrap_or(ObjectType::Undefined);
219                if matches!(kind, ObjectType::ObjectPolicy) {
220                    return Err(ParseError::Structural {
221                        location,
222                        message: "DROP POLICY in source is not supported — drops happen \
223                                  via diff"
224                            .into(),
225                    });
226                }
227                if matches!(kind, ObjectType::ObjectAggregate) {
228                    return Err(ParseError::Structural {
229                        location,
230                        message: "DROP AGGREGATE in source is not supported — drops happen \
231                                  via diff"
232                            .into(),
233                    });
234                }
235                Err(unsupported(location, "DROP"))
236            }
237            NodeEnum::AlterExtensionStmt(_) => Err(ParseError::Structural {
238                location,
239                message: "ALTER EXTENSION is not supported in source files — \
240                          declare the desired state via CREATE EXTENSION"
241                    .into(),
242            }),
243            NodeEnum::CreateTableAsStmt(s) => {
244                // `CREATE TABLE ... AS SELECT` and `CREATE MATERIALIZED VIEW`
245                // both arrive as CreateTableAsStmt. Route by the objtype field.
246                match ObjectType::try_from(s.objtype) {
247                    Ok(ObjectType::ObjectMatview) => Ok(Self::CreateMaterializedView(*s)),
248                    _ => Err(unsupported(location, "CREATE TABLE AS SELECT")),
249                }
250            }
251            other => Err(unsupported(location, friendly_kind(&other))),
252        }
253    }
254}
255
256/// Returns `true` when the `AlterTableStmt` is exactly one `ATTACH PARTITION`
257/// sub-command so the classifier can route it to the dedicated variant.
258fn is_attach_partition_stmt(stmt: &protobuf::AlterTableStmt) -> bool {
259    use pg_query::protobuf::AlterTableType;
260    if stmt.cmds.len() != 1 {
261        return false;
262    }
263    match &stmt.cmds[0].node {
264        Some(NodeEnum::AlterTableCmd(c)) => AlterTableType::try_from(c.subtype)
265            .ok()
266            .is_some_and(|t| matches!(t, AlterTableType::AtAttachPartition)),
267        _ => false,
268    }
269}
270
271const fn unsupported(location: SourceLocation, kind: &'static str) -> ParseError {
272    ParseError::UnsupportedObjectKind { location, kind }
273}
274
275/// Translate non-whitelisted node kinds to a human-readable label for diagnostics.
276#[allow(clippy::match_same_arms)]
277const fn friendly_kind(node: &NodeEnum) -> &'static str {
278    match node {
279        NodeEnum::ViewStmt(_) => "CREATE VIEW", // never reached — routed above
280        NodeEnum::CreateEnumStmt(_) => "CREATE TYPE ... AS ENUM", // never reached — routed above
281        NodeEnum::CreateFunctionStmt(_) => "CREATE FUNCTION/PROCEDURE", // never reached — routed above
282        NodeEnum::CreateTrigStmt(_) => "CREATE TRIGGER", // never reached — routed above
283        NodeEnum::CreateRangeStmt(_) => "CREATE TYPE ... AS RANGE", // never reached — routed above
284        NodeEnum::CreateExtensionStmt(_) => "CREATE EXTENSION", // never reached — routed above
285        NodeEnum::CreatePolicyStmt(_) => "CREATE POLICY", // never reached — routed above
286        NodeEnum::CreateForeignTableStmt(_) => "CREATE FOREIGN TABLE",
287        NodeEnum::CreateFdwStmt(_) => "CREATE FOREIGN DATA WRAPPER",
288        NodeEnum::CreateForeignServerStmt(_) => "CREATE FOREIGN SERVER",
289        NodeEnum::CreateRoleStmt(_) => "CREATE ROLE",
290        NodeEnum::GrantStmt(_) => "GRANT/REVOKE", // never reached — routed above
291        NodeEnum::GrantRoleStmt(_) => "GRANT/REVOKE ROLE",
292        NodeEnum::CreateTableAsStmt(_) => "CREATE TABLE AS",
293        NodeEnum::CreateAmStmt(_) => "CREATE ACCESS METHOD",
294        NodeEnum::CreateEventTrigStmt(_) => "CREATE EVENT TRIGGER",
295        NodeEnum::CreateOpClassStmt(_) => "CREATE OPERATOR CLASS",
296        NodeEnum::CreateOpFamilyStmt(_) => "CREATE OPERATOR FAMILY",
297        NodeEnum::CreatePlangStmt(_) => "CREATE LANGUAGE",
298        NodeEnum::CreateStatsStmt(_) => "CREATE STATISTICS",
299        NodeEnum::CreateUserMappingStmt(_) => "CREATE USER MAPPING",
300        NodeEnum::CreateTableSpaceStmt(_) => "CREATE TABLESPACE",
301        NodeEnum::CreatedbStmt(_) => "CREATE DATABASE",
302        NodeEnum::DefineStmt(_) => "CREATE AGGREGATE/OPERATOR/etc.",
303        NodeEnum::RuleStmt(_) => "CREATE RULE",
304        NodeEnum::DropStmt(_) => "DROP",
305        NodeEnum::TruncateStmt(_) => "TRUNCATE",
306        NodeEnum::SelectStmt(_) => "SELECT",
307        NodeEnum::InsertStmt(_) => "INSERT",
308        NodeEnum::UpdateStmt(_) => "UPDATE",
309        NodeEnum::DeleteStmt(_) => "DELETE",
310        NodeEnum::CopyStmt(_) => "COPY",
311        NodeEnum::TransactionStmt(_) => "BEGIN/COMMIT/ROLLBACK",
312        _ => "this statement kind",
313    }
314}
315
316#[cfg(test)]
317mod tests {
318    use super::*;
319    use std::path::PathBuf;
320
321    fn loc() -> SourceLocation {
322        SourceLocation::new(PathBuf::from("test.sql"), 1, 1)
323    }
324
325    fn first_node(sql: &str) -> NodeEnum {
326        let parsed = pg_query::parse(sql).expect("pg_query parses");
327        parsed
328            .protobuf
329            .stmts
330            .into_iter()
331            .next()
332            .and_then(|raw| raw.stmt)
333            .and_then(|n| n.node)
334            .expect("at least one statement")
335    }
336
337    #[test]
338    fn create_table_classifies() {
339        let node = first_node("CREATE TABLE app.users (id integer);");
340        let stmt = Statement::classify(node, loc()).unwrap();
341        assert!(matches!(stmt, Statement::CreateTable(_)));
342    }
343
344    #[test]
345    fn create_schema_classifies() {
346        let node = first_node("CREATE SCHEMA app;");
347        let stmt = Statement::classify(node, loc()).unwrap();
348        assert!(matches!(stmt, Statement::CreateSchema(_)));
349    }
350
351    #[test]
352    fn create_index_classifies() {
353        let node = first_node("CREATE INDEX users_email_idx ON app.users (email);");
354        let stmt = Statement::classify(node, loc()).unwrap();
355        assert!(matches!(stmt, Statement::CreateIndex(_)));
356    }
357
358    #[test]
359    fn create_sequence_classifies() {
360        let node = first_node("CREATE SEQUENCE app.seq1;");
361        let stmt = Statement::classify(node, loc()).unwrap();
362        assert!(matches!(stmt, Statement::CreateSequence(_)));
363    }
364
365    #[test]
366    fn alter_table_classifies() {
367        let node = first_node(
368            "ALTER TABLE app.invoices ADD CONSTRAINT fk1 FOREIGN KEY (cid) REFERENCES app.c(id);",
369        );
370        let stmt = Statement::classify(node, loc()).unwrap();
371        assert!(matches!(stmt, Statement::AlterTable(_)));
372    }
373
374    #[test]
375    fn comment_classifies() {
376        let node = first_node("COMMENT ON TABLE app.users IS 'people';");
377        let stmt = Statement::classify(node, loc()).unwrap();
378        assert!(matches!(stmt, Statement::Comment(_)));
379    }
380
381    #[test]
382    fn create_view_classifies() {
383        let node = first_node("CREATE VIEW app.v AS SELECT 1;");
384        let stmt = Statement::classify(node, loc()).unwrap();
385        assert!(matches!(stmt, Statement::CreateView(_)));
386    }
387
388    #[test]
389    fn create_materialized_view_classifies() {
390        let node = first_node(
391            "CREATE MATERIALIZED VIEW app.mv AS SELECT count(*) FROM app.t WITH NO DATA;",
392        );
393        let stmt = Statement::classify(node, loc()).unwrap();
394        assert!(matches!(stmt, Statement::CreateMaterializedView(_)));
395    }
396
397    #[test]
398    fn create_table_as_select_unsupported() {
399        let node = first_node("CREATE TABLE app.t2 AS SELECT 1;");
400        let err = Statement::classify(node, loc()).unwrap_err();
401        assert!(matches!(err, ParseError::UnsupportedObjectKind { .. }));
402    }
403
404    #[test]
405    fn create_function_classifies() {
406        let node =
407            first_node("CREATE FUNCTION app.f() RETURNS integer AS $$ SELECT 1; $$ LANGUAGE sql;");
408        let stmt = Statement::classify(node, loc()).unwrap();
409        assert!(matches!(stmt, Statement::CreateFunction(_)));
410    }
411
412    #[test]
413    fn create_procedure_classifies() {
414        let node =
415            first_node("CREATE PROCEDURE app.p() LANGUAGE plpgsql AS $$ BEGIN NULL; END $$;");
416        let stmt = Statement::classify(node, loc()).unwrap();
417        assert!(matches!(stmt, Statement::CreateProcedure(_)));
418    }
419
420    #[test]
421    fn create_extension_classifies() {
422        let node = first_node("CREATE EXTENSION pgcrypto;");
423        let stmt = Statement::classify(node, loc()).unwrap();
424        assert!(matches!(stmt, Statement::CreateExtension(_)));
425    }
426
427    #[test]
428    fn alter_extension_rejected() {
429        let node = first_node("ALTER EXTENSION pgcrypto UPDATE;");
430        let err = Statement::classify(node, loc()).unwrap_err();
431        assert!(matches!(err, ParseError::Structural { .. }));
432    }
433
434    #[test]
435    fn select_unsupported() {
436        let node = first_node("SELECT 1;");
437        let err = Statement::classify(node, loc()).unwrap_err();
438        assert!(matches!(err, ParseError::UnsupportedObjectKind { .. }));
439    }
440}
pgevolve_core/parse/statement.rs

pgevolve_core/parse/
statement.rs
