Analyze Docker Build Errors

Docker Build Error Analysis

Analyze Dockerfile and build logs for PHP project build failures and provide targeted fixes.

Common Build Error Patterns

Detection Patterns

1. Extension Compilation Failure

# ERROR: gd extension on Alpine
RUN docker-php-ext-install gd
# configure: error: png.h not found

# FIX (Alpine):
RUN apk add --no-cache libpng-dev libjpeg-turbo-dev freetype-dev \
    && docker-php-ext-configure gd --with-freetype --with-jpeg \
    && docker-php-ext-install -j$(nproc) gd

# FIX (Debian):
RUN apt-get update && apt-get install -y libpng-dev libjpeg62-turbo-dev libfreetype6-dev \
    && docker-php-ext-configure gd --with-freetype --with-jpeg \
    && docker-php-ext-install -j$(nproc) gd

2. Extension Dependencies by Base Image

3. Memory Exhausted During Build

# ERROR: Composer runs out of memory
RUN composer install
# PHP Fatal error: Allowed memory size of 134217728 bytes exhausted

# FIX: Increase memory limit for Composer
RUN php -d memory_limit=-1 /usr/bin/composer install --no-dev --optimize-autoloader

4. Context Too Large

# Required .dockerignore entries
.git
node_modules
vendor
var/cache
var/log
docker-compose*.yml
.env.local
tests
docs

5. Alpine Build Essentials

RUN apk add --no-cache --virtual .build-deps \
    $PHPIZE_DEPS build-base autoconf \
    && pecl install redis \
    && docker-php-ext-enable redis \
    && apk del .build-deps

Grep Patterns

# Find Dockerfiles with extension installs
Grep: "docker-php-ext-install" --glob "**/Dockerfile*"

# Find missing dev package installs before ext-install
Grep: "ext-install.*(gd|intl|zip|pdo_pgsql|imagick)" --glob "**/Dockerfile*"

# Find unrestricted memory Composer runs
Grep: "composer install|composer update" --glob "**/Dockerfile*"

# Find large base images
Grep: "FROM php:[0-9.]+-apache|FROM php:[0-9.]+-cli$" --glob "**/Dockerfile*"

# Check for .dockerignore existence
Glob: "**/.dockerignore"

Root Cause Analysis

Build Fails on CI but Works Locally

1. Different Docker version -- check docker version output
2. No BuildKit -- CI may not have DOCKER_BUILDKIT=1
3. Cache differences -- CI has cold cache, local has warm
4. Platform mismatch -- local ARM (M1/M2), CI AMD64

Extension Fails Only on Alpine

1. musl vs glibc -- some extensions require glibc patches
2. Package naming -- Alpine uses different package names
3. Missing build tools -- add build-base for compilation

Fix Templates

Alpine

RUN apk add --no-cache --virtual .build-deps $PHPIZE_DEPS <DEV_PACKAGES> \
    && docker-php-ext-configure <EXT> <OPTIONS> \
    && docker-php-ext-install -j$(nproc) <EXT> \
    && apk del .build-deps \
    && apk add --no-cache <RUNTIME_PACKAGES>

Debian

RUN apt-get update \
    && apt-get install -y --no-install-recommends <DEV_PACKAGES> \
    && docker-php-ext-configure <EXT> <OPTIONS> \
    && docker-php-ext-install -j$(nproc) <EXT> \
    && apt-get purge -y --auto-remove <DEV_ONLY_PACKAGES> \
    && rm -rf /var/lib/apt/lists/*

Severity Classification

Output Format

### Build Error: [Category]

**Severity:** Critical/Major/Minor
**Stage:** `FROM ... AS <stage>`
**Line:** Dockerfile:line

**Error Message:**
<exact error from build log>

**Root Cause:**
[Explanation of why the build fails]

**Fix:**
```dockerfile
// Corrected Dockerfile instruction

Prevention: [How to avoid this error in future builds]