Initial commit

Dockerfile

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+from alpine:3.20
+
+run apk add sqlite
+
+copy entrypoint.sh /
+copy lints.sql /
+run chmod +x /entrypoint.sh
+
+entrypoint ["/entrypoint.sh"]

action.yml

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+# action.yml
+name: SQLite schema lint
+description: Enforce constraints on SQLite schemas
+inputs:
+  schema-file:
+    description: SQL schema file that will create
+    required: true
+runs:
+  using: 'docker'
+  image: 'Dockerfile'
+  args:
+    - ${{ inputs.schema-file }}

entrypoint.sh

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+#!/bin/sh -l
+
+set -x
+set -e
+
+if [ -z "$1" ]; then
+	echo "No SQL schema file given!  Exiting..."
+	exit 1
+fi
+
+DB_PATH=/tmp/database.db
+SCHEMA_PATH="$GITHUB_WORKSPACE/$1"
+echo $GITHUB_WORKSPACE
+echo $SCHEMA_PATH
+
+# Create the database
+sqlite3 $DB_PATH < $SCHEMA_PATH
+
+output=$(sqlite3 -column -header $DB_PATH < lints.sql)
+if [ -n "$output" ]; then
+	echo "Some checks failed."
+	echo
+	echo $output
+	exit 2
+fi

lints.sql

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+create temporary view tables as
+    -- select * from sqlite_schema where type = 'table';
+    select l.* from sqlite_schema s left join pragma_table_list l on s.name = l.name where s.type = 'table';
+
+
+create temporary view columns as
+    select tables.name as table_name,
+           table_info.name as column_name,
+           table_info.type as column_type,
+           "notnull",
+           dflt_value,
+           pk as is_primary_key,
+           fk."table" as fk_target_table,
+           fk."to" as fk_target_column
+      from tables
+      join pragma_table_info(tables.name) as table_info
+ left join pragma_foreign_key_list(tables.name) as fk on fk."from" = column_name;
+
+
+-- ======================
+-- Lint-check definitions
+-- ======================
+
+-- Require all fields to be not null, unless they are foreign keys
+create temporary view lint_check__require_not_null as
+    select 'Column should should be "not null"' as error_msg,
+           tables.name as table_name,
+           table_info.name as column_name
+      from tables
+      join pragma_table_info(tables.name) as table_info
+     where not exists (
+                select 1 from pragma_foreign_key_list(tables.name) as fk
+                 where fk."from" = table_info.name
+               )
+       and (table_info."notnull" = 0 and table_info.pk = 0);
+
+
+-- Require all non-foreign-key, non-primary-key fields to have a default value
+create temporary view lint_check__require_default_values as
+    select 'Column should have a default value' as error_msg,
+           tables.name as table_name,
+           table_info.name as column_name
+      from tables
+      join pragma_table_info(tables.name) as table_info
+     where table_info.pk = 0
+       and not exists (
+                select 1 from pragma_foreign_key_list(tables.name) as fk
+                 where fk."from" = table_info.name
+               )
+       and table_info.dflt_value is null;
+
+
+-- All tables should be STRICT (must specify column types; types must be int, integer, real, text,
+-- blob or any).  This disallows all 'date' and 'time' columns automatically.
+-- See more: https://www.sqlite.org/stricttables.html
+create temporary view lint_check__require_strict as
+    select 'Table should be marked "strict"' as error_msg,
+           name as table_name,
+           '' as column_name
+      from tables
+     where strict = 0
+       and name not in ('sqlite_schema', 'sqlite_temp_schema');
+
+
+-- Forbid use 'int' column types
+create temporary view lint_check__forbid_int_type as
+    select 'Column should use "integer" type instead of "int"' as error_msg,
+           tables.name as table_name,
+           table_info.name as column_name
+      from tables
+      join pragma_table_info(tables.name) as table_info
+     where table_info.type like 'int';
+
+
+-- tables must have a primary key; if it's rowid, it has to be named explicitly
+create temporary view lint_check__require_explicit_primary_key as
+    select 'Table should declare an explicit primary key' as error_msg,
+           tables.name as table_name,
+           '' as column_name
+      from tables
+     where not exists (select name from pragma_table_info(tables.name) where pk != 0);
+
+
+-- columns referenced by foreign keys must have indexes
+create temporary view lint_check__require_indexes_for_foreign_keys as
+with index_info as (
+        select indexes.name as index_name,
+               tables.name as table_name,
+               columns.name as column_name,
+               case when origin = 'c' then 'regular' when origin = 'u' then 'unique' when origin = 'pk' then 'primary key' else origin end as index_type
+          from tables
+          join pragma_index_list(tables.name) as indexes
+          join pragma_index_info(indexes.name) as columns
+
+         union
+
+        select '[auto-generated rowid primary key index]' as index_name,
+               tables.name as table_name,
+               columns.name as column_name,
+               'primary key' as index_type
+          from tables
+          join pragma_table_info(tables.name) as "columns"
+         where columns.name = 'rowid'
+           and columns.pk != 0 -- `pk` is either 0, or the 1-based index of the column within the primary key
+    ), foreign_key_targets as (
+        select tables.name as "fk_source_table",
+               fk."from" as "fk_source_column",
+               fk."table" as fk_target_table,
+               fk."to" as fk_target_column
+          from tables
+          join pragma_foreign_key_list(tables.name) as fk
+    )
+select fk_source_table, fk_source_column, fk_target_table, fk_target_column, ifnull(index_info.table_name, 'NULL') as index_table, ifnull(index_info.column_name, 'NULL') as index_column
+  from foreign_key_targets
+  left join index_info on foreign_key_targets.fk_target_table = index_info.table_name and foreign_key_targets.fk_target_column = index_info.column_name
+ where index_column = 'NULL';
+
+
+-- ==============
+-- Run the checks
+-- ==============
+
+-- select * from columns;
+
+select * from (
+    select * from lint_check__require_not_null
+ -- union
+ --    select * from lint_check__require_default_values
+ union
+    select * from lint_check__require_strict
+ union
+    select * from lint_check__forbid_int_type
+ union
+    select * from lint_check__require_explicit_primary_key
+ union
+    select 'Foreign keys should point to indexed columns' as error_msg,
+           fk_source_table as table_name,
+           fk_source_column as column_name
+      from lint_check__require_indexes_for_foreign_keys
+);
+

test_schemas/failure-has-foreign-key-no-index.sql

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+create table stuff (
+    rowid integer primary key,
+    data text not null,
+    amount integer not null
+) strict;
+
+create table stuff2 (
+    weird_pk integer primary key,
+    label text not null unique,
+    stuff_id integer references stuff(rowid),
+    alternative_stuff_id integer references stuff(amount)
+) strict;

test_schemas/failure-has-ints.sql

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+create table stuff (
+    rowid integer primary key,
+    data text not null,
+    amount integer not null
+) strict;
+create index index_stuff_amount on stuff (amount);
+
+create table stuff2 (
+    weird_pk integer primary key,
+    label text not null unique,
+    stuff_id int references stuff(rowid),
+    alternative_stuff_id integer references stuff(amount)
+) strict;

test_schemas/failure-has-nulls.sql

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+create table stuff (
+    rowid integer primary key,
+    data text not null,
+    amount integer
+) strict;
+create index index_stuff_amount on stuff (amount);
+
+create table stuff2 (
+    weird_pk integer primary key,
+    label text not null unique,
+    stuff_id integer references stuff(rowid),
+    alternative_stuff_id integer references stuff(amount)
+) strict;

test_schemas/failure-no-strict.sql

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+create table stuff (
+    rowid integer primary key,
+    data text not null,
+    amount integer not null
+) strict;
+create index index_stuff_amount on stuff (amount);
+
+create table stuff2 (
+    weird_pk integer primary key,
+    label text not null unique,
+    stuff_id integer references stuff(rowid),
+    alternative_stuff_id integer references stuff(amount)
+);

test_schemas/success.sql

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+create table stuff (
+    rowid integer primary key,
+    data text not null,
+    amount integer not null
+) strict;
+create index index_stuff_amount on stuff (amount);
+
+create table stuff2 (
+    weird_pk integer primary key,
+    label text not null unique,
+    stuff_id integer references stuff(rowid),
+    alternative_stuff_id integer references stuff(amount)
+) strict;

test_schemas/total-failure.sql

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+PRAGMA foreign_keys = on;
+
+
+create table implicit_rowid (
+    a integer
+);
+
+create table explicit_rowid_not_pk (
+	rowid integer
+);
+
+create table explicit_rowid (
+	rowid integer primary key
+);
+
+create table without_rowid (
+	a integer primary key
+) without rowid;
+
+create table multi_column (
+	a int,
+	b integer,
+	primary key(a, b)
+);
+
+create table foreign_key_missing_index (
+	a references implicit_rowid(a)
+);