Check SQL for errors too (#27)

Author: levkk

docs/features/sharding/cross-shard.md

@@ -132,7 +132,7 @@ Some statements, like `CREATE INDEX CONCURRENTLY`, cannot run inside transaction
 
 ```postgresql
 DROP INDEX IF EXISTS user_id_idx;
-CREATE INDEX CONCURRENTLY user_id_idx USING btree(user_id);
+CREATE INDEX CONCURRENTLY user_id_idx ON users USING btree(user_id);
 ```
 
 ## Under the hood

docs/features/sharding/schema_management/primary_keys.md

@@ -25,7 +25,11 @@ CREATE TABLE users (
 If you run this command through PgDog, this table will be created on all shards. Underneath, Postgres expands `BIGSERIAL` to the following code:
 
 ```postgresql
-BIGINT NOT NULL DEFAULT nextval('users_id_seq'::regclass)
+CREATE TABLE users (
+    id BIGINT UNIQUE NOT NULL DEFAULT nextval('users_id_seq'::regclass),
+    email VARCHAR NOT NULL,
+    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
+);
 ```
 
 The `users_id_seq` is a sequence, automatically created by Postgres, that will be used to generate unique values for inserted rows that don't provide one for the `id` column.

docs/features/sharding/supported-queries.md

@@ -24,10 +24,10 @@ Postgres has 3 kinds of queries, each handled a little bit differently in a shar
 
 ```postgresql
 -- Sharding key equals a single value
-SELECT * FROM users WHERE user_id = $1
+SELECT * FROM users WHERE user_id = $1;
 
 -- Sharding keys IN tuple
-SELECT * FROM users WHERE id IN ($1, $2, $3)
+SELECT * FROM users WHERE id IN ($1, $2, $3);
 ```
 
 Queries that don't match this pattern will currently be routed to all shards. We are continuously adding support for more complex patterns.

tests/requirements.txt

@@ -1,2 +1,3 @@
 markdown-it-py
 regex
+pglast

tests/test_code_blocks.py

@@ -5,12 +5,20 @@
 import subprocess
 from markdown_it import MarkdownIt
 import sys
+import pglast
 
 from regex import sub
 from regex.regex import Regex, RegexFlag
 mdp = MarkdownIt()
 
-pattern = re.compile(r'(?msi)^(?P<fence>[`~]{3,})[ \t]*toml\b[^\n]*\r?\n(?P<code>.*?)^(?P=fence)[ \t]*\r?$',)
+pattern = re.compile(
+    r'(?msi)^(?P<fence>[`~]{3,})[^\n]*\r?\n(?P<code>.*?)^(?P=fence)[ \t]*\r?$'
+)
+
+replication = [
+    "CREATE_REPLICATION_SLOT",
+    "START_REPLICATION",
+]
 
 def verify(binary):
     for file in glob.glob("docs/**/*.md",
@@ -27,6 +35,17 @@ def verify(binary):
                         pass
                     else:
                         check_file(binary, "pgdog", token.content)
+                elif token.type == "fence" and token.info == "postgresql":
+                    try:
+                        pglast.parser.parse_sql(token.content)
+                    except Exception as e:
+                        found = False
+                        for cmd in replication:
+                            if cmd in token.content:
+                                found = True
+                        if not found:
+                            print(token.content)
+                            raise e
 
 def check_file(binary, kind, content):
     tmp = f"/tmp/pgdog_config_test.toml"