feat(sql-to-rest): friendly 'not supported yet' errors

packages/sql-to-rest/src/processor.ts

@@ -170,19 +170,19 @@ export async function processSql(sql: string) {
  * Converts a pg-query `Stmt` into a PostgREST-compatible `Statement`.
  */
 function processStmt({ stmt }: Stmt): Statement {
-  const keys = Object.keys(stmt) as unknown as (keyof typeof stmt)[]
-
-  if (keys.length > 1) {
-    throw new Error(`stmt contains multiple statements: ${JSON.stringify(keys)}`)
-  }
-
-  const [stmtType] = keys
-
-  switch (stmtType) {
-    case 'SelectStmt':
-      return processSelectStmt(stmt)
-    default:
-      throw new Error(`Unsupported stmt type '${stmtType}'`)
+  if ('SelectStmt' in stmt) {
+    return processSelectStmt(stmt)
+  } else if ('InsertStmt' in stmt) {
+    throw new Error(`Insert statements are not yet supported by the translator`)
+  } else if ('UpdateStmt' in stmt) {
+    throw new Error(`Update statements are not yet supported by the translator`)
+  } else if ('DeleteStmt' in stmt) {
+    throw new Error(`Delete statements are not yet supported by the translator`)
+  } else if ('ExplainStmt' in stmt) {
+    throw new Error(`Explain statements are not yet supported by the translator`)
+  } else {
+    const [stmtType] = Object.keys(stmt)
+    throw new Error(`Unsupported stmt type '${stmtType}'`)
   }
 }
 
@@ -195,6 +195,10 @@ function processSelectStmt(stmt: SelectStmt): Select {
     throw new Error('Only one FROM source is supported')
   }
 
+  if (stmt.SelectStmt.withClause) {
+    throw new Error('WITH clauses are not supported')
+  }
+
   const [fromClause] = stmt.SelectStmt.fromClause
 
   const { from, alias, embeddedTargets } = processFromClause(fromClause)

packages/sql-to-rest/src/types/libpg-query.ts

@@ -187,6 +187,7 @@ export type SelectStmt = {
     groupClause?: any[]
     groupDistinct?: boolean
     havingClause?: any[]
+    withClause?: any
     sortClause?: SortBy[]
     limitOption: string
     limitCount?: A_Const
@@ -195,8 +196,26 @@ export type SelectStmt = {
   }
 }
 
+export type InsertStmt = {
+  InsertStmt: {}
+}
+
+export type UpdateStmt = {
+  UpdateStmt: {}
+}
+
+export type DeleteStmt = {
+  DeleteStmt: {}
+}
+
+export type ExplainStmt = {
+  ExplainStmt: {
+    query: SelectStmt | InsertStmt | UpdateStmt | DeleteStmt
+  }
+}
+
 export type Stmt = {
-  stmt: SelectStmt
+  stmt: SelectStmt | InsertStmt | UpdateStmt | DeleteStmt | ExplainStmt
 }
 
 export type ParsedQuery = {