Docker PHP Configuration Checker

Analyze PHP configuration within Docker environments for production readiness.

Configuration Checks

1. php.ini Production vs Development

# BAD: Development config
RUN cp /usr/local/etc/php/php.ini-development /usr/local/etc/php/php.ini

# GOOD: Production config
RUN cp /usr/local/etc/php/php.ini-production /usr/local/etc/php/php.ini

2. OPcache Configuration

; GOOD: OPcache optimized for production
opcache.enable=1
opcache.memory_consumption=256
opcache.interned_strings_buffer=16
opcache.max_accelerated_files=20000
opcache.validate_timestamps=0
opcache.save_comments=1

3. OPcache JIT (PHP 8.4+)

opcache.jit=1255
opcache.jit_buffer_size=128M

4. PHP-FPM Pool Configuration

; BAD: Static pm wastes memory; ondemand has fork overhead
pm = static
pm.max_children = 100

; GOOD: Dynamic pm with tuned values
pm = dynamic
pm.max_children = 50
pm.start_servers = 10
pm.min_spare_servers = 5
pm.max_spare_servers = 20
pm.max_requests = 1000

5. Memory Limit

; BAD: Unlimited memory
memory_limit = -1

; GOOD: Appropriate for workload
memory_limit = 128M   ; web
memory_limit = 256M   ; workers
memory_limit = 512M   ; batch

6. Error Reporting

; BAD: Development error display
display_errors = On

; GOOD: Production settings
display_errors = Off
display_startup_errors = Off
log_errors = On
error_log = /proc/self/fd/2
error_reporting = E_ALL & ~E_DEPRECATED & ~E_STRICT

7. Session Handling

; BAD: File-based sessions (not scalable)
session.save_handler = files

; GOOD: External storage
session.save_handler = redis
session.save_path = "tcp://redis:6379"

8. Upload Limits

upload_max_filesize = 20M
post_max_size = 25M
max_file_uploads = 10

9. Timezone

date.timezone = UTC

10. Realpath Cache

; GOOD: Increased for Symfony/Laravel
realpath_cache_size = 4096K
realpath_cache_ttl = 600

Grep Patterns

Grep: "php.ini-(production|development)" --glob "**/Dockerfile*"
Grep: "opcache\\." --glob "**/{Dockerfile*,*.ini,*.conf}"
Grep: "^pm[. =]" --glob "**/*.conf"
Grep: "memory_limit" --glob "**/{Dockerfile*,*.ini,*.conf}"
Grep: "display_errors" --glob "**/{Dockerfile*,*.ini,*.conf}"
Grep: "session\\.save_handler" --glob "**/{Dockerfile*,*.ini,*.conf}"
Grep: "upload_max_filesize|post_max_size" --glob "**/{Dockerfile*,*.ini,*.conf}"
Grep: "date\\.timezone" --glob "**/{Dockerfile*,*.ini,*.conf}"
Grep: "realpath_cache" --glob "**/{Dockerfile*,*.ini,*.conf}"
Grep: "opcache\\.jit" --glob "**/{Dockerfile*,*.ini,*.conf}"

Detection Sources

1. Dockerfile RUN echo — inline php.ini directives
2. COPY’d php.ini — full configuration replacement
3. COPY’d conf.d/*.ini — modular config files
4. PHP-FPM pool config — www.conf or custom pools
5. Environment variables — PHP_INI_SCAN_DIR overrides

Severity Classification

Output Format

### PHP Config Issue: [Description]

**Severity:** Critical/Major/Minor
**Setting:** `directive = value`
**Location:** `Dockerfile:line` or `config-file:line`

**Current Value:**
```ini
directive = current_value

Recommended Value:

directive = recommended_value

Rationale: [Why this setting matters for production]