Add wpdb fallback for wp db query and wp db import when mysql/mariadb binary is unavailable

README.md

@@ -81,7 +81,7 @@ wp db create [--dbuser=<value>] [--dbpass=<value>] [--defaults]
 
 Runs `CREATE_DATABASE` SQL statement using `DB_HOST`, `DB_NAME`,
 `DB_USER` and `DB_PASSWORD` database credentials specified in
-wp-config.php.
+wp-config.php. Requires MySQL/MariaDB client binaries to be available.
 
 **OPTIONS**
 
@@ -111,7 +111,7 @@ wp db drop [--dbuser=<value>] [--dbpass=<value>] [--yes] [--defaults]
 
 Runs `DROP_DATABASE` SQL statement using `DB_HOST`, `DB_NAME`,
 `DB_USER` and `DB_PASSWORD` database credentials specified in
-wp-config.php.
+wp-config.php. Requires MySQL/MariaDB client binaries to be available.
 
 **OPTIONS**
 
@@ -144,7 +144,7 @@ wp db reset [--dbuser=<value>] [--dbpass=<value>] [--yes] [--defaults]
 
 Runs `DROP_DATABASE` and `CREATE_DATABASE` SQL statements using
 `DB_HOST`, `DB_NAME`, `DB_USER` and `DB_PASSWORD` database credentials
-specified in wp-config.php.
+specified in wp-config.php. Requires MySQL/MariaDB client binaries to be available.
 
 **OPTIONS**
 
@@ -177,7 +177,7 @@ wp db check [--dbuser=<value>] [--dbpass=<value>] [--<field>=<value>] [--default
 
 Runs `mysqlcheck` utility with `--check` using `DB_HOST`,
 `DB_NAME`, `DB_USER` and `DB_PASSWORD` database credentials
-specified in wp-config.php.
+specified in wp-config.php. Requires `mysqlcheck` or `mariadb-check` client binary.
 
 [See docs](http://dev.mysql.com/doc/refman/5.7/en/check-table.html)
 for more details on the `CHECK TABLE` statement.
@@ -216,7 +216,7 @@ wp db optimize [--dbuser=<value>] [--dbpass=<value>] [--<field>=<value>] [--defa
 
 Runs `mysqlcheck` utility with `--optimize=true` using `DB_HOST`,
 `DB_NAME`, `DB_USER` and `DB_PASSWORD` database credentials
-specified in wp-config.php.
+specified in wp-config.php. Requires `mysqlcheck` or `mariadb-check` client binary.
 
 [See docs](http://dev.mysql.com/doc/refman/5.7/en/optimize-table.html)
 for more details on the `OPTIMIZE TABLE` statement.
@@ -269,7 +269,7 @@ wp db repair [--dbuser=<value>] [--dbpass=<value>] [--<field>=<value>] [--defaul
 
 Runs `mysqlcheck` utility with `--repair=true` using `DB_HOST`,
 `DB_NAME`, `DB_USER` and `DB_PASSWORD` database credentials
-specified in wp-config.php.
+specified in wp-config.php. Requires `mysqlcheck` or `mariadb-check` client binary.
 
 [See docs](http://dev.mysql.com/doc/refman/5.7/en/repair-table.html) for
 more details on the `REPAIR TABLE` statement.
@@ -297,14 +297,16 @@ more details on the `REPAIR TABLE` statement.
 
 ### wp db cli
 
-Opens a MySQL console using credentials from wp-config.php
+Opens a MySQL console using credentials from wp-config.php.
 
 ~~~
 wp db cli [--database=<database>] [--default-character-set=<character-set>] [--dbuser=<value>] [--dbpass=<value>] [--<field>=<value>] [--defaults]
 ~~~
 
 **Alias:** `connect`
 
+Requires `mysql` or `mariadb` client binary to be available.
+
 **OPTIONS**
 
 	[--database=<database>]
@@ -342,7 +344,9 @@ wp db query [<sql>] [--dbuser=<value>] [--dbpass=<value>] [--<field>=<value>] [-
 ~~~
 
 Executes an arbitrary SQL query using `DB_HOST`, `DB_NAME`, `DB_USER`
- and `DB_PASSWORD` database credentials specified in wp-config.php.
+and `DB_PASSWORD` database credentials specified in wp-config.php.
+If MySQL/MariaDB client binaries are not available, falls back to
+executing queries via WordPress's `wpdb`.
 
 Use the `--skip-column-names` MySQL argument to exclude the headers
 from a SELECT query. Pipe the output to remove the ASCII table
@@ -445,6 +449,7 @@ wp db export [<file>] [--dbuser=<value>] [--dbpass=<value>] [--<field>=<value>]
 
 Runs `mysqldump` utility using `DB_HOST`, `DB_NAME`, `DB_USER` and
 `DB_PASSWORD` database credentials specified in wp-config.php. Accepts any valid [`mysqldump` flags](https://dev.mysql.com/doc/en/mysqldump.html#mysqldump-option-summary).
+Requires `mysqldump` or `mariadb-dump` client binary to be available.
 
 **OPTIONS**
 
@@ -536,7 +541,8 @@ wp db import [<file>] [--dbuser=<value>] [--dbpass=<value>] [--<field>=<value>]
 Runs SQL queries using `DB_HOST`, `DB_NAME`, `DB_USER` and
 `DB_PASSWORD` database credentials specified in wp-config.php. This
 does not create database by itself and only performs whatever tasks are
-defined in the SQL.
+defined in the SQL. If MySQL/MariaDB client binaries are not available,
+falls back to importing via WordPress's `wpdb`.
 
 **OPTIONS**
 

features/db-import.feature

@@ -69,6 +69,118 @@ Feature: Import a WordPress database
       Success: Imported from 'wp_cli_test.sql'.
       """
 
+  @require-mysql-or-mariadb
+  Scenario: Database import falls back to wpdb when mysql binary is unavailable
+    Given a WP install
+    And a fake-bin/mysql file:
+      """
+      #!/bin/sh
+      exit 127
+      """
+    And a fake-bin/mariadb file:
+      """
+      #!/bin/sh
+      exit 127
+      """
+
+    When I try `wp db export wp_cli_test.sql`
+    Then the wp_cli_test.sql file should exist
+
+    When I run `chmod +x fake-bin/mysql fake-bin/mariadb`
+    And I try `env PATH={RUN_DIR}/fake-bin:$PATH wp db import wp_cli_test.sql --debug`
+    Then STDOUT should be:
+      """
+      Success: Imported from 'wp_cli_test.sql'.
+      """
+    And STDERR should contain:
+      """
+      MySQL/MariaDB binary not available, falling back to wpdb for import.
+      """
+
+  @require-mysql-or-mariadb
+  Scenario: Database import falls back to wpdb and handles zero-date column defaults
+    Given a WP install
+    And a fake-bin/mysql file:
+      """
+      #!/bin/sh
+      exit 127
+      """
+    And a fake-bin/mariadb file:
+      """
+      #!/bin/sh
+      exit 127
+      """
+    And a zero_date.sql file:
+      """
+      CREATE TABLE IF NOT EXISTS wp_zero_date_test (
+        id INT AUTO_INCREMENT PRIMARY KEY,
+        created_at DATETIME NOT NULL DEFAULT '0000-00-00 00:00:00'
+      );
+      """
+
+    When I run `chmod +x fake-bin/mysql fake-bin/mariadb`
+    And I try `env PATH={RUN_DIR}/fake-bin:$PATH wp db import zero_date.sql --debug`
+    Then STDOUT should be:
+      """
+      Success: Imported from 'zero_date.sql'.
+      """
+
+  @require-mysql-or-mariadb
+  Scenario: Database import falls back to wpdb and handles DELIMITER blocks with procedures
+    Given a WP install
+    And a fake-bin/mysql file:
+      """
+      #!/bin/sh
+      exit 127
+      """
+    And a fake-bin/mariadb file:
+      """
+      #!/bin/sh
+      exit 127
+      """
+    And a procedure.sql file:
+      """
+      DELIMITER //
+      CREATE PROCEDURE wp_test_procedure()
+      BEGIN
+        SELECT 1;
+      END//
+      DELIMITER ;
+      """
+
+    When I run `chmod +x fake-bin/mysql fake-bin/mariadb`
+    And I try `env PATH={RUN_DIR}/fake-bin:$PATH wp db import procedure.sql --debug`
+    Then STDOUT should be:
+      """
+      Success: Imported from 'procedure.sql'.
+      """
+
+  @require-mysql-or-mariadb
+  Scenario: Database import falls back to wpdb and handles malformed empty DELIMITER lines
+    Given a WP install
+    And a fake-bin/mysql file:
+      """
+      #!/bin/sh
+      exit 127
+      """
+    And a fake-bin/mariadb file:
+      """
+      #!/bin/sh
+      exit 127
+      """
+    And a malformed_delimiter.sql file:
+      """
+      DELIMITER
+      SELECT 1;
+      """
+
+    When I run `chmod +x fake-bin/mysql fake-bin/mariadb`
+    And I try `env PATH={RUN_DIR}/fake-bin:$PATH wp db import malformed_delimiter.sql --debug`
+    Then STDOUT should be:
+      """
+      Success: Imported from 'malformed_delimiter.sql'.
+      """
+
   # SQLite doesn't support the --dbuser flag.
   @require-mysql-or-mariadb
   Scenario: Import from database name path by default with passed-in dbuser/dbpass

features/db-query.feature

@@ -155,3 +155,56 @@ Feature: Query the database with WordPress' MySQL config
       """
       skip-ssl-verify-server-cert
       """
+
+  @require-mysql-or-mariadb
+  Scenario: Database querying falls back to wpdb when mysql binary is unavailable
+    Given a WP install
+    And a fake-bin/mysql file:
+      """
+      #!/bin/sh
+      exit 127
+      """
+    And a fake-bin/mariadb file:
+      """
+      #!/bin/sh
+      exit 127
+      """
+
+    When I run `chmod +x fake-bin/mysql fake-bin/mariadb`
+    And I try `env PATH={RUN_DIR}/fake-bin:$PATH wp db query "SELECT COUNT(ID) FROM wp_users;" --debug`
+    Then STDOUT should be:
+      """
+      COUNT(ID)
+      1
+      """
+    And STDERR should contain:
+      """
+      MySQL/MariaDB binary not available, falling back to wpdb.
+      """
+
+  @require-mysql-or-mariadb
+  Scenario: Database querying falls back to wpdb for multi-statement queries when mysql binary is unavailable
+    Given a WP install
+    And a fake-bin/mysql file:
+      """
+      #!/bin/sh
+      exit 127
+      """
+    And a fake-bin/mariadb file:
+      """
+      #!/bin/sh
+      exit 127
+      """
+
+    When I run `chmod +x fake-bin/mysql fake-bin/mariadb`
+    And I try `env PATH={RUN_DIR}/fake-bin:$PATH wp db query "SELECT 1 as num; SELECT 2 as num;" --debug`
+    Then STDOUT should contain:
+      """
+      num
+      1
+      """
+    And STDOUT should contain:
+      """
+      num
+      2
+      """

features/db.feature

@@ -387,8 +387,8 @@ Feature: Perform database operations
       Query succeeded. Rows affected: 1
       """
 
-  @require-sqlite @skip-windows
   # Skipped on Windows due to persistent file locking issues when run via Behat.
+  @require-sqlite @skip-windows
   Scenario: SQLite DB CRUD operations
     Given a WP install
     And a session_yes file: