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}
73
74impl Statement {
75    /// Classify a node into the supported whitelist, or return
76    /// [`ParseError::UnsupportedObjectKind`] for anything else.
77    #[allow(clippy::too_many_lines)] // one arm per supported `NodeEnum` variant; the dispatch table is the function.
78    pub fn classify(node: NodeEnum, location: SourceLocation) -> Result<Self, ParseError> {
79        match node {
80            NodeEnum::CreateSchemaStmt(s) => Ok(Self::CreateSchema(s)),
81            NodeEnum::CreateStmt(s) => Ok(Self::CreateTable(s)),
82            NodeEnum::CreateSeqStmt(s) => Ok(Self::CreateSequence(s)),
83            NodeEnum::IndexStmt(s) => Ok(Self::CreateIndex(*s)),
84            NodeEnum::AlterTableStmt(s) => {
85                if is_attach_partition_stmt(&s) {
86                    Ok(Self::AlterTableAttachPartition(s))
87                } else {
88                    Ok(Self::AlterTable(s))
89                }
90            }
91            NodeEnum::CommentStmt(s) => Ok(Self::Comment(*s)),
92            NodeEnum::ViewStmt(s) => Ok(Self::CreateView(*s)),
93            NodeEnum::CreateEnumStmt(s) => Ok(Self::CreateEnum(s)),
94            NodeEnum::CreateDomainStmt(s) => Ok(Self::CreateDomain(*s)),
95            NodeEnum::CompositeTypeStmt(s) => Ok(Self::CreateCompositeType(s)),
96            NodeEnum::CreateRangeStmt(s) => Ok(Self::CreateRange(s)),
97            NodeEnum::CreateFunctionStmt(s) => {
98                if s.is_procedure {
99                    Ok(Self::CreateProcedure(*s))
100                } else {
101                    Ok(Self::CreateFunction(*s))
102                }
103            }
104            NodeEnum::CreateExtensionStmt(s) => Ok(Self::CreateExtension(s)),
105            NodeEnum::CreateTrigStmt(s) => Ok(Self::CreateTrigger(*s)),
106            NodeEnum::GrantStmt(s) => Ok(Self::Grant(s)),
107            NodeEnum::AlterOwnerStmt(s) => Ok(Self::AlterOwner(*s)),
108            NodeEnum::AlterDefaultPrivilegesStmt(s) => Ok(Self::AlterDefaultPrivileges(s)),
109            NodeEnum::CreatePolicyStmt(s) => Ok(Self::CreatePolicy(*s)),
110            NodeEnum::CreatePublicationStmt(s) => Ok(Self::CreatePublication(s)),
111            NodeEnum::AlterPublicationStmt(s) => Ok(Self::AlterPublication(s)),
112            NodeEnum::CreateSubscriptionStmt(s) => Ok(Self::CreateSubscription(s)),
113            NodeEnum::AlterSubscriptionStmt(s) => Ok(Self::AlterSubscription(s)),
114            NodeEnum::CreateStatsStmt(s) => Ok(Self::CreateStatistics(s)),
115            NodeEnum::AlterStatsStmt(s) => Ok(Self::AlterStatistics(*s)),
116            NodeEnum::DefineStmt(s) => {
117                let kind = ObjectType::try_from(s.kind).unwrap_or(ObjectType::Undefined);
118                if matches!(kind, ObjectType::ObjectCollation) {
119                    Ok(Self::CreateCollation(s))
120                } else {
121                    Err(unsupported(location, "CREATE AGGREGATE/OPERATOR/etc."))
122                }
123            }
124            NodeEnum::RenameStmt(s) => {
125                use pg_query::protobuf::ObjectType;
126                let rename_type =
127                    ObjectType::try_from(s.rename_type).unwrap_or(ObjectType::Undefined);
128                if matches!(rename_type, ObjectType::ObjectPublication) {
129                    return Err(ParseError::Structural {
130                        location,
131                        message: "ALTER PUBLICATION … RENAME TO is not supported in pgevolve \
132                                  (pgevolve never models renames)"
133                            .into(),
134                    });
135                }
136                if matches!(rename_type, ObjectType::ObjectSubscription) {
137                    // Recover the subscription name for the error (subname is in
138                    // RenameStmt.relation for subscriptions).
139                    let sub_name = s
140                        .relation
141                        .as_ref()
142                        .map_or_else(|| String::from("<unknown>"), |r| r.relname.clone());
143                    let id = crate::identifier::Identifier::from_unquoted(&sub_name)
144                        .unwrap_or_else(|_| {
145                            crate::identifier::Identifier::from_unquoted("subscription")
146                                .expect("static identifier")
147                        });
148                    return Err(ParseError::SubscriptionRenameNotSupported(id, location));
149                }
150                if matches!(rename_type, ObjectType::ObjectStatisticExt) {
151                    // RenameStmt for statistics encodes the name in `s.subname` (the
152                    // new name) and `s.relation` (the old qualified name).
153                    let schema = s
154                        .relation
155                        .as_ref()
156                        .map_or_else(String::new, |r| r.schemaname.clone());
157                    let name = s
158                        .relation
159                        .as_ref()
160                        .map_or_else(|| String::from("<unknown>"), |r| r.relname.clone());
161                    let schema_id = crate::identifier::Identifier::from_unquoted(&schema)
162                        .unwrap_or_else(|_| {
163                            crate::identifier::Identifier::from_unquoted("unknown")
164                                .expect("static identifier")
165                        });
166                    let name_id = crate::identifier::Identifier::from_unquoted(&name)
167                        .unwrap_or_else(|_| {
168                            crate::identifier::Identifier::from_unquoted("statistic")
169                                .expect("static identifier")
170                        });
171                    let qname = crate::identifier::QualifiedName::new(schema_id, name_id);
172                    return Err(ParseError::StatisticRenameNotSupported(qname, location));
173                }
174                Err(unsupported(location, "RENAME"))
175            }
176            NodeEnum::AlterPolicyStmt(_) => Err(ParseError::Structural {
177                location,
178                message: "ALTER POLICY in source is not supported — policy modifications \
179                          happen via diff; use CREATE POLICY in source"
180                    .into(),
181            }),
182            NodeEnum::DropStmt(s) => {
183                let kind = ObjectType::try_from(s.remove_type).unwrap_or(ObjectType::Undefined);
184                if matches!(kind, ObjectType::ObjectPolicy) {
185                    return Err(ParseError::Structural {
186                        location,
187                        message: "DROP POLICY in source is not supported — drops happen \
188                                  via diff"
189                            .into(),
190                    });
191                }
192                Err(unsupported(location, "DROP"))
193            }
194            NodeEnum::AlterExtensionStmt(_) => Err(ParseError::Structural {
195                location,
196                message: "ALTER EXTENSION is not supported in source files — \
197                          declare the desired state via CREATE EXTENSION"
198                    .into(),
199            }),
200            NodeEnum::CreateTableAsStmt(s) => {
201                // `CREATE TABLE ... AS SELECT` and `CREATE MATERIALIZED VIEW`
202                // both arrive as CreateTableAsStmt. Route by the objtype field.
203                match ObjectType::try_from(s.objtype) {
204                    Ok(ObjectType::ObjectMatview) => Ok(Self::CreateMaterializedView(*s)),
205                    _ => Err(unsupported(location, "CREATE TABLE AS SELECT")),
206                }
207            }
208            other => Err(unsupported(location, friendly_kind(&other))),
209        }
210    }
211}
212
213/// Returns `true` when the `AlterTableStmt` is exactly one `ATTACH PARTITION`
214/// sub-command so the classifier can route it to the dedicated variant.
215fn is_attach_partition_stmt(stmt: &protobuf::AlterTableStmt) -> bool {
216    use pg_query::protobuf::AlterTableType;
217    if stmt.cmds.len() != 1 {
218        return false;
219    }
220    match &stmt.cmds[0].node {
221        Some(NodeEnum::AlterTableCmd(c)) => AlterTableType::try_from(c.subtype)
222            .ok()
223            .is_some_and(|t| matches!(t, AlterTableType::AtAttachPartition)),
224        _ => false,
225    }
226}
227
228const fn unsupported(location: SourceLocation, kind: &'static str) -> ParseError {
229    ParseError::UnsupportedObjectKind { location, kind }
230}
231
232/// Translate non-whitelisted node kinds to a human-readable label for diagnostics.
233#[allow(clippy::match_same_arms)]
234const fn friendly_kind(node: &NodeEnum) -> &'static str {
235    match node {
236        NodeEnum::ViewStmt(_) => "CREATE VIEW", // never reached — routed above
237        NodeEnum::CreateEnumStmt(_) => "CREATE TYPE ... AS ENUM", // never reached — routed above
238        NodeEnum::CreateFunctionStmt(_) => "CREATE FUNCTION/PROCEDURE", // never reached — routed above
239        NodeEnum::CreateTrigStmt(_) => "CREATE TRIGGER", // never reached — routed above
240        NodeEnum::CreateRangeStmt(_) => "CREATE TYPE ... AS RANGE", // never reached — routed above
241        NodeEnum::CreateExtensionStmt(_) => "CREATE EXTENSION", // never reached — routed above
242        NodeEnum::CreatePolicyStmt(_) => "CREATE POLICY", // never reached — routed above
243        NodeEnum::CreateForeignTableStmt(_) => "CREATE FOREIGN TABLE",
244        NodeEnum::CreateFdwStmt(_) => "CREATE FOREIGN DATA WRAPPER",
245        NodeEnum::CreateForeignServerStmt(_) => "CREATE FOREIGN SERVER",
246        NodeEnum::CreateRoleStmt(_) => "CREATE ROLE",
247        NodeEnum::GrantStmt(_) => "GRANT/REVOKE", // never reached — routed above
248        NodeEnum::GrantRoleStmt(_) => "GRANT/REVOKE ROLE",
249        NodeEnum::CreateTableAsStmt(_) => "CREATE TABLE AS",
250        NodeEnum::CreateAmStmt(_) => "CREATE ACCESS METHOD",
251        NodeEnum::CreateEventTrigStmt(_) => "CREATE EVENT TRIGGER",
252        NodeEnum::CreateOpClassStmt(_) => "CREATE OPERATOR CLASS",
253        NodeEnum::CreateOpFamilyStmt(_) => "CREATE OPERATOR FAMILY",
254        NodeEnum::CreatePlangStmt(_) => "CREATE LANGUAGE",
255        NodeEnum::CreateStatsStmt(_) => "CREATE STATISTICS",
256        NodeEnum::CreateUserMappingStmt(_) => "CREATE USER MAPPING",
257        NodeEnum::CreateTableSpaceStmt(_) => "CREATE TABLESPACE",
258        NodeEnum::CreatedbStmt(_) => "CREATE DATABASE",
259        NodeEnum::DefineStmt(_) => "CREATE AGGREGATE/OPERATOR/etc.",
260        NodeEnum::RuleStmt(_) => "CREATE RULE",
261        NodeEnum::DropStmt(_) => "DROP",
262        NodeEnum::TruncateStmt(_) => "TRUNCATE",
263        NodeEnum::SelectStmt(_) => "SELECT",
264        NodeEnum::InsertStmt(_) => "INSERT",
265        NodeEnum::UpdateStmt(_) => "UPDATE",
266        NodeEnum::DeleteStmt(_) => "DELETE",
267        NodeEnum::CopyStmt(_) => "COPY",
268        NodeEnum::TransactionStmt(_) => "BEGIN/COMMIT/ROLLBACK",
269        _ => "this statement kind",
270    }
271}
272
273#[cfg(test)]
274mod tests {
275    use super::*;
276    use std::path::PathBuf;
277
278    fn loc() -> SourceLocation {
279        SourceLocation::new(PathBuf::from("test.sql"), 1, 1)
280    }
281
282    fn first_node(sql: &str) -> NodeEnum {
283        let parsed = pg_query::parse(sql).expect("pg_query parses");
284        parsed
285            .protobuf
286            .stmts
287            .into_iter()
288            .next()
289            .and_then(|raw| raw.stmt)
290            .and_then(|n| n.node)
291            .expect("at least one statement")
292    }
293
294    #[test]
295    fn create_table_classifies() {
296        let node = first_node("CREATE TABLE app.users (id integer);");
297        let stmt = Statement::classify(node, loc()).unwrap();
298        assert!(matches!(stmt, Statement::CreateTable(_)));
299    }
300
301    #[test]
302    fn create_schema_classifies() {
303        let node = first_node("CREATE SCHEMA app;");
304        let stmt = Statement::classify(node, loc()).unwrap();
305        assert!(matches!(stmt, Statement::CreateSchema(_)));
306    }
307
308    #[test]
309    fn create_index_classifies() {
310        let node = first_node("CREATE INDEX users_email_idx ON app.users (email);");
311        let stmt = Statement::classify(node, loc()).unwrap();
312        assert!(matches!(stmt, Statement::CreateIndex(_)));
313    }
314
315    #[test]
316    fn create_sequence_classifies() {
317        let node = first_node("CREATE SEQUENCE app.seq1;");
318        let stmt = Statement::classify(node, loc()).unwrap();
319        assert!(matches!(stmt, Statement::CreateSequence(_)));
320    }
321
322    #[test]
323    fn alter_table_classifies() {
324        let node = first_node(
325            "ALTER TABLE app.invoices ADD CONSTRAINT fk1 FOREIGN KEY (cid) REFERENCES app.c(id);",
326        );
327        let stmt = Statement::classify(node, loc()).unwrap();
328        assert!(matches!(stmt, Statement::AlterTable(_)));
329    }
330
331    #[test]
332    fn comment_classifies() {
333        let node = first_node("COMMENT ON TABLE app.users IS 'people';");
334        let stmt = Statement::classify(node, loc()).unwrap();
335        assert!(matches!(stmt, Statement::Comment(_)));
336    }
337
338    #[test]
339    fn create_view_classifies() {
340        let node = first_node("CREATE VIEW app.v AS SELECT 1;");
341        let stmt = Statement::classify(node, loc()).unwrap();
342        assert!(matches!(stmt, Statement::CreateView(_)));
343    }
344
345    #[test]
346    fn create_materialized_view_classifies() {
347        let node = first_node(
348            "CREATE MATERIALIZED VIEW app.mv AS SELECT count(*) FROM app.t WITH NO DATA;",
349        );
350        let stmt = Statement::classify(node, loc()).unwrap();
351        assert!(matches!(stmt, Statement::CreateMaterializedView(_)));
352    }
353
354    #[test]
355    fn create_table_as_select_unsupported() {
356        let node = first_node("CREATE TABLE app.t2 AS SELECT 1;");
357        let err = Statement::classify(node, loc()).unwrap_err();
358        assert!(matches!(err, ParseError::UnsupportedObjectKind { .. }));
359    }
360
361    #[test]
362    fn create_function_classifies() {
363        let node =
364            first_node("CREATE FUNCTION app.f() RETURNS integer AS $$ SELECT 1; $$ LANGUAGE sql;");
365        let stmt = Statement::classify(node, loc()).unwrap();
366        assert!(matches!(stmt, Statement::CreateFunction(_)));
367    }
368
369    #[test]
370    fn create_procedure_classifies() {
371        let node =
372            first_node("CREATE PROCEDURE app.p() LANGUAGE plpgsql AS $$ BEGIN NULL; END $$;");
373        let stmt = Statement::classify(node, loc()).unwrap();
374        assert!(matches!(stmt, Statement::CreateProcedure(_)));
375    }
376
377    #[test]
378    fn create_extension_classifies() {
379        let node = first_node("CREATE EXTENSION pgcrypto;");
380        let stmt = Statement::classify(node, loc()).unwrap();
381        assert!(matches!(stmt, Statement::CreateExtension(_)));
382    }
383
384    #[test]
385    fn alter_extension_rejected() {
386        let node = first_node("ALTER EXTENSION pgcrypto UPDATE;");
387        let err = Statement::classify(node, loc()).unwrap_err();
388        assert!(matches!(err, ParseError::Structural { .. }));
389    }
390
391    #[test]
392    fn select_unsupported() {
393        let node = first_node("SELECT 1;");
394        let err = Statement::classify(node, loc()).unwrap_err();
395        assert!(matches!(err, ParseError::UnsupportedObjectKind { .. }));
396    }
397}
pgevolve_core/parse/statement.rs

pgevolve_core/parse/
statement.rs
