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 [OR REPLACE] FUNCTION ...`.
39    CreateFunction(protobuf::CreateFunctionStmt),
40    /// `CREATE [OR REPLACE] PROCEDURE ...`.
41    CreateProcedure(protobuf::CreateFunctionStmt),
42    /// `CREATE EXTENSION ...`.
43    CreateExtension(protobuf::CreateExtensionStmt),
44    /// `CREATE [CONSTRAINT] TRIGGER ...`.
45    CreateTrigger(protobuf::CreateTrigStmt),
46    /// `ALTER TABLE parent ATTACH PARTITION child FOR VALUES ...`.
47    AlterTableAttachPartition(protobuf::AlterTableStmt),
48    /// `GRANT priv ON obj TO grantee` — object-level grant (not REVOKE, not role grant).
49    Grant(protobuf::GrantStmt),
50    /// `ALTER <kind> name OWNER TO role`.
51    AlterOwner(protobuf::AlterOwnerStmt),
52    /// `ALTER DEFAULT PRIVILEGES ... GRANT ...`.
53    AlterDefaultPrivileges(protobuf::AlterDefaultPrivilegesStmt),
54    /// `CREATE POLICY name ON table ...`.
55    CreatePolicy(protobuf::CreatePolicyStmt),
56    /// `CREATE PUBLICATION name ...`.
57    CreatePublication(protobuf::CreatePublicationStmt),
58    /// `ALTER PUBLICATION name ...`.
59    AlterPublication(protobuf::AlterPublicationStmt),
60    /// `CREATE SUBSCRIPTION name CONNECTION ... PUBLICATION ...`.
61    CreateSubscription(protobuf::CreateSubscriptionStmt),
62    /// `ALTER SUBSCRIPTION name ...`.
63    AlterSubscription(protobuf::AlterSubscriptionStmt),
64}
65
66impl Statement {
67    /// Classify a node into the supported whitelist, or return
68    /// [`ParseError::UnsupportedObjectKind`] for anything else.
69    pub fn classify(node: NodeEnum, location: SourceLocation) -> Result<Self, ParseError> {
70        match node {
71            NodeEnum::CreateSchemaStmt(s) => Ok(Self::CreateSchema(s)),
72            NodeEnum::CreateStmt(s) => Ok(Self::CreateTable(s)),
73            NodeEnum::CreateSeqStmt(s) => Ok(Self::CreateSequence(s)),
74            NodeEnum::IndexStmt(s) => Ok(Self::CreateIndex(*s)),
75            NodeEnum::AlterTableStmt(s) => {
76                if is_attach_partition_stmt(&s) {
77                    Ok(Self::AlterTableAttachPartition(s))
78                } else {
79                    Ok(Self::AlterTable(s))
80                }
81            }
82            NodeEnum::CommentStmt(s) => Ok(Self::Comment(*s)),
83            NodeEnum::ViewStmt(s) => Ok(Self::CreateView(*s)),
84            NodeEnum::CreateEnumStmt(s) => Ok(Self::CreateEnum(s)),
85            NodeEnum::CreateDomainStmt(s) => Ok(Self::CreateDomain(*s)),
86            NodeEnum::CompositeTypeStmt(s) => Ok(Self::CreateCompositeType(s)),
87            NodeEnum::CreateFunctionStmt(s) => {
88                if s.is_procedure {
89                    Ok(Self::CreateProcedure(*s))
90                } else {
91                    Ok(Self::CreateFunction(*s))
92                }
93            }
94            NodeEnum::CreateExtensionStmt(s) => Ok(Self::CreateExtension(s)),
95            NodeEnum::CreateTrigStmt(s) => Ok(Self::CreateTrigger(*s)),
96            NodeEnum::GrantStmt(s) => Ok(Self::Grant(s)),
97            NodeEnum::AlterOwnerStmt(s) => Ok(Self::AlterOwner(*s)),
98            NodeEnum::AlterDefaultPrivilegesStmt(s) => Ok(Self::AlterDefaultPrivileges(s)),
99            NodeEnum::CreatePolicyStmt(s) => Ok(Self::CreatePolicy(*s)),
100            NodeEnum::CreatePublicationStmt(s) => Ok(Self::CreatePublication(s)),
101            NodeEnum::AlterPublicationStmt(s) => Ok(Self::AlterPublication(s)),
102            NodeEnum::CreateSubscriptionStmt(s) => Ok(Self::CreateSubscription(s)),
103            NodeEnum::AlterSubscriptionStmt(s) => Ok(Self::AlterSubscription(s)),
104            NodeEnum::RenameStmt(s) => {
105                use pg_query::protobuf::ObjectType;
106                let rename_type =
107                    ObjectType::try_from(s.rename_type).unwrap_or(ObjectType::Undefined);
108                if matches!(rename_type, ObjectType::ObjectPublication) {
109                    return Err(ParseError::Structural {
110                        location,
111                        message: "ALTER PUBLICATION … RENAME TO is not supported in pgevolve \
112                                  (pgevolve never models renames)"
113                            .into(),
114                    });
115                }
116                if matches!(rename_type, ObjectType::ObjectSubscription) {
117                    // Recover the subscription name for the error (subname is in
118                    // RenameStmt.relation for subscriptions).
119                    let sub_name = s
120                        .relation
121                        .as_ref()
122                        .map_or_else(|| String::from("<unknown>"), |r| r.relname.clone());
123                    let id = crate::identifier::Identifier::from_unquoted(&sub_name)
124                        .unwrap_or_else(|_| {
125                            crate::identifier::Identifier::from_unquoted("subscription")
126                                .expect("static identifier")
127                        });
128                    return Err(ParseError::SubscriptionRenameNotSupported(id, location));
129                }
130                Err(unsupported(location, "RENAME"))
131            }
132            NodeEnum::AlterPolicyStmt(_) => Err(ParseError::Structural {
133                location,
134                message: "ALTER POLICY in source is not supported — policy modifications \
135                          happen via diff; use CREATE POLICY in source"
136                    .into(),
137            }),
138            NodeEnum::DropStmt(s) => {
139                let kind = ObjectType::try_from(s.remove_type).unwrap_or(ObjectType::Undefined);
140                if matches!(kind, ObjectType::ObjectPolicy) {
141                    return Err(ParseError::Structural {
142                        location,
143                        message: "DROP POLICY in source is not supported — drops happen \
144                                  via diff"
145                            .into(),
146                    });
147                }
148                Err(unsupported(location, "DROP"))
149            }
150            NodeEnum::AlterExtensionStmt(_) => Err(ParseError::Structural {
151                location,
152                message: "ALTER EXTENSION is not supported in source files — \
153                          declare the desired state via CREATE EXTENSION"
154                    .into(),
155            }),
156            NodeEnum::CreateTableAsStmt(s) => {
157                // `CREATE TABLE ... AS SELECT` and `CREATE MATERIALIZED VIEW`
158                // both arrive as CreateTableAsStmt. Route by the objtype field.
159                match ObjectType::try_from(s.objtype) {
160                    Ok(ObjectType::ObjectMatview) => Ok(Self::CreateMaterializedView(*s)),
161                    _ => Err(unsupported(location, "CREATE TABLE AS SELECT")),
162                }
163            }
164            other => Err(unsupported(location, friendly_kind(&other))),
165        }
166    }
167}
168
169/// Returns `true` when the `AlterTableStmt` is exactly one `ATTACH PARTITION`
170/// sub-command so the classifier can route it to the dedicated variant.
171fn is_attach_partition_stmt(stmt: &protobuf::AlterTableStmt) -> bool {
172    use pg_query::protobuf::AlterTableType;
173    if stmt.cmds.len() != 1 {
174        return false;
175    }
176    match &stmt.cmds[0].node {
177        Some(NodeEnum::AlterTableCmd(c)) => AlterTableType::try_from(c.subtype)
178            .ok()
179            .is_some_and(|t| matches!(t, AlterTableType::AtAttachPartition)),
180        _ => false,
181    }
182}
183
184const fn unsupported(location: SourceLocation, kind: &'static str) -> ParseError {
185    ParseError::UnsupportedObjectKind { location, kind }
186}
187
188/// Translate non-whitelisted node kinds to a human-readable label for diagnostics.
189#[allow(clippy::match_same_arms)]
190const fn friendly_kind(node: &NodeEnum) -> &'static str {
191    match node {
192        NodeEnum::ViewStmt(_) => "CREATE VIEW", // never reached — routed above
193        NodeEnum::CreateEnumStmt(_) => "CREATE TYPE ... AS ENUM", // never reached — routed above
194        NodeEnum::CreateFunctionStmt(_) => "CREATE FUNCTION/PROCEDURE", // never reached — routed above
195        NodeEnum::CreateTrigStmt(_) => "CREATE TRIGGER", // never reached — routed above
196        NodeEnum::CreateRangeStmt(_) => "CREATE TYPE ... AS RANGE",
197        NodeEnum::CreateExtensionStmt(_) => "CREATE EXTENSION", // never reached — routed above
198        NodeEnum::CreatePolicyStmt(_) => "CREATE POLICY",       // never reached — routed above
199        NodeEnum::CreateForeignTableStmt(_) => "CREATE FOREIGN TABLE",
200        NodeEnum::CreateFdwStmt(_) => "CREATE FOREIGN DATA WRAPPER",
201        NodeEnum::CreateForeignServerStmt(_) => "CREATE FOREIGN SERVER",
202        NodeEnum::CreateRoleStmt(_) => "CREATE ROLE",
203        NodeEnum::GrantStmt(_) => "GRANT/REVOKE", // never reached — routed above
204        NodeEnum::GrantRoleStmt(_) => "GRANT/REVOKE ROLE",
205        NodeEnum::CreateTableAsStmt(_) => "CREATE TABLE AS",
206        NodeEnum::CreateAmStmt(_) => "CREATE ACCESS METHOD",
207        NodeEnum::CreateEventTrigStmt(_) => "CREATE EVENT TRIGGER",
208        NodeEnum::CreateOpClassStmt(_) => "CREATE OPERATOR CLASS",
209        NodeEnum::CreateOpFamilyStmt(_) => "CREATE OPERATOR FAMILY",
210        NodeEnum::CreatePlangStmt(_) => "CREATE LANGUAGE",
211        NodeEnum::CreateStatsStmt(_) => "CREATE STATISTICS",
212        NodeEnum::CreateUserMappingStmt(_) => "CREATE USER MAPPING",
213        NodeEnum::CreateTableSpaceStmt(_) => "CREATE TABLESPACE",
214        NodeEnum::CreatedbStmt(_) => "CREATE DATABASE",
215        NodeEnum::DefineStmt(_) => "CREATE AGGREGATE/OPERATOR/etc.",
216        NodeEnum::RuleStmt(_) => "CREATE RULE",
217        NodeEnum::DropStmt(_) => "DROP",
218        NodeEnum::TruncateStmt(_) => "TRUNCATE",
219        NodeEnum::SelectStmt(_) => "SELECT",
220        NodeEnum::InsertStmt(_) => "INSERT",
221        NodeEnum::UpdateStmt(_) => "UPDATE",
222        NodeEnum::DeleteStmt(_) => "DELETE",
223        NodeEnum::CopyStmt(_) => "COPY",
224        NodeEnum::TransactionStmt(_) => "BEGIN/COMMIT/ROLLBACK",
225        _ => "this statement kind",
226    }
227}
228
229#[cfg(test)]
230mod tests {
231    use super::*;
232    use std::path::PathBuf;
233
234    fn loc() -> SourceLocation {
235        SourceLocation::new(PathBuf::from("test.sql"), 1, 1)
236    }
237
238    fn first_node(sql: &str) -> NodeEnum {
239        let parsed = pg_query::parse(sql).expect("pg_query parses");
240        parsed
241            .protobuf
242            .stmts
243            .into_iter()
244            .next()
245            .and_then(|raw| raw.stmt)
246            .and_then(|n| n.node)
247            .expect("at least one statement")
248    }
249
250    #[test]
251    fn create_table_classifies() {
252        let node = first_node("CREATE TABLE app.users (id integer);");
253        let stmt = Statement::classify(node, loc()).unwrap();
254        assert!(matches!(stmt, Statement::CreateTable(_)));
255    }
256
257    #[test]
258    fn create_schema_classifies() {
259        let node = first_node("CREATE SCHEMA app;");
260        let stmt = Statement::classify(node, loc()).unwrap();
261        assert!(matches!(stmt, Statement::CreateSchema(_)));
262    }
263
264    #[test]
265    fn create_index_classifies() {
266        let node = first_node("CREATE INDEX users_email_idx ON app.users (email);");
267        let stmt = Statement::classify(node, loc()).unwrap();
268        assert!(matches!(stmt, Statement::CreateIndex(_)));
269    }
270
271    #[test]
272    fn create_sequence_classifies() {
273        let node = first_node("CREATE SEQUENCE app.seq1;");
274        let stmt = Statement::classify(node, loc()).unwrap();
275        assert!(matches!(stmt, Statement::CreateSequence(_)));
276    }
277
278    #[test]
279    fn alter_table_classifies() {
280        let node = first_node(
281            "ALTER TABLE app.invoices ADD CONSTRAINT fk1 FOREIGN KEY (cid) REFERENCES app.c(id);",
282        );
283        let stmt = Statement::classify(node, loc()).unwrap();
284        assert!(matches!(stmt, Statement::AlterTable(_)));
285    }
286
287    #[test]
288    fn comment_classifies() {
289        let node = first_node("COMMENT ON TABLE app.users IS 'people';");
290        let stmt = Statement::classify(node, loc()).unwrap();
291        assert!(matches!(stmt, Statement::Comment(_)));
292    }
293
294    #[test]
295    fn create_view_classifies() {
296        let node = first_node("CREATE VIEW app.v AS SELECT 1;");
297        let stmt = Statement::classify(node, loc()).unwrap();
298        assert!(matches!(stmt, Statement::CreateView(_)));
299    }
300
301    #[test]
302    fn create_materialized_view_classifies() {
303        let node = first_node(
304            "CREATE MATERIALIZED VIEW app.mv AS SELECT count(*) FROM app.t WITH NO DATA;",
305        );
306        let stmt = Statement::classify(node, loc()).unwrap();
307        assert!(matches!(stmt, Statement::CreateMaterializedView(_)));
308    }
309
310    #[test]
311    fn create_table_as_select_unsupported() {
312        let node = first_node("CREATE TABLE app.t2 AS SELECT 1;");
313        let err = Statement::classify(node, loc()).unwrap_err();
314        assert!(matches!(err, ParseError::UnsupportedObjectKind { .. }));
315    }
316
317    #[test]
318    fn create_function_classifies() {
319        let node =
320            first_node("CREATE FUNCTION app.f() RETURNS integer AS $$ SELECT 1; $$ LANGUAGE sql;");
321        let stmt = Statement::classify(node, loc()).unwrap();
322        assert!(matches!(stmt, Statement::CreateFunction(_)));
323    }
324
325    #[test]
326    fn create_procedure_classifies() {
327        let node =
328            first_node("CREATE PROCEDURE app.p() LANGUAGE plpgsql AS $$ BEGIN NULL; END $$;");
329        let stmt = Statement::classify(node, loc()).unwrap();
330        assert!(matches!(stmt, Statement::CreateProcedure(_)));
331    }
332
333    #[test]
334    fn create_extension_classifies() {
335        let node = first_node("CREATE EXTENSION pgcrypto;");
336        let stmt = Statement::classify(node, loc()).unwrap();
337        assert!(matches!(stmt, Statement::CreateExtension(_)));
338    }
339
340    #[test]
341    fn alter_extension_rejected() {
342        let node = first_node("ALTER EXTENSION pgcrypto UPDATE;");
343        let err = Statement::classify(node, loc()).unwrap_err();
344        assert!(matches!(err, ParseError::Structural { .. }));
345    }
346
347    #[test]
348    fn select_unsupported() {
349        let node = first_node("SELECT 1;");
350        let err = Statement::classify(node, loc()).unwrap_err();
351        assert!(matches!(err, ParseError::UnsupportedObjectKind { .. }));
352    }
353}
pgevolve_core/parse/statement.rs

pgevolve_core/parse/
statement.rs
