Actor: Replace Docling CLI with docling-serve API

This commit transitions the Actor from using the full Docling CLI package to the more lightweight docling-serve API. Key changes include:

- Redesign Dockerfile to use docling-serve as base image
- Update actor.sh to communicate with API instead of running CLI commands
- Improve content type handling for various output formats
- Update input schema to align with API parameters
- Reduce Docker image size from ~6GB to ~600MB
- Update documentation and changelog to reflect architectural changes

The image size reduction will make the Actor more cost-effective for users while maintaining all existing functionality including OCR capabilities.

Issue: No official docling-serve Docker image is currently available, which will be addressed in a future commit.
Signed-off-by: Václav Vančura <commit@vancura.dev>

.actor/CHANGELOG.md

@@ -5,6 +5,24 @@ All notable changes to the Docling Actor will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [1.1.0] - 2025-03-15
+
+### Changed
+
+- Switched from full Docling CLI to docling-serve API
+- Dramatically reduced Docker image size (from ~6GB to ~600MB)
+- Improved API compatibility with docling-serve
+- Better content type handling for different output formats
+- Updated error handling to align with API responses
+
+### Technical Details
+
+- Actor Specification v1
+- Using ds4sd/docling-serve:latest base image
+- Node.js 20.x for Apify CLI
+- Eliminated Python dependencies
+- Simplified Docker build process
+
 ## [1.0.0] - 2025-02-07
 
 ### Added

.actor/Dockerfile

@@ -1,57 +1,36 @@
-ARG ACTOR_PATH_IN_DOCKER_CONTEXT
-
-FROM python:3.11-slim-bookworm
+FROM ds4sd/docling-serve:latest
 
 LABEL maintainer="Vaclav Vancura <@vancura>"
 LABEL description="Apify Actor for document processing using Docling"
-LABEL version="1.0.0"
+LABEL version="1.1.0"
 
-RUN groupadd -r appuser && useradd -r -g appuser -s /sbin/nologin appuser && \
-    \
-    apt-get update && apt-get install -y --no-install-recommends bash curl file git gpg jo jq procps xz-utils && \
-    \
-    mkdir -p /etc/apt/keyrings && \
-    curl -fsSL https://deb.nodesource.com/gpgkey/nodesource-repo.gpg.key | gpg --dearmor -o /etc/apt/keyrings/nodesource.gpg && \
-    echo "deb [signed-by=/etc/apt/keyrings/nodesource.gpg] https://deb.nodesource.com/node_20.x nodistro main" | tee /etc/apt/sources.list.d/nodesource.list && \
-    \
-    apt-get update && apt-get install -y nodejs && apt-get clean && \
-    \
-    rm -rf /var/lib/apt/lists/* && \
-    \
-    pip install --no-cache-dir --upgrade pip && \
-    pip install --no-cache-dir docling==2.17.0 && \
-    \
-    npm install -g npm@latest && \
-    npm install -g apify-cli && \
-    npm cache clean --force && \
-    \
-    mkdir -p /home/appuser && \
-    chown -R appuser:appuser /home/appuser && \
-    \
-    apt-get update && apt-get install -y --no-install-recommends \
-    time \
+# Install necessary dependencies for the Apify Actor
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    curl \
+    gpg \
+    jq \
+    xz-utils \
+    jo \
     procps \
-    && apt-get clean \
     && rm -rf /var/lib/apt/lists/*
 
+# Install Node.js for Apify CLI
+RUN mkdir -p /etc/apt/keyrings && \
+    curl -fsSL https://deb.nodesource.com/gpgkey/nodesource-repo.gpg.key | gpg --dearmor -o /etc/apt/keyrings/nodesource.gpg && \
+    echo "deb [signed-by=/etc/apt/keyrings/nodesource.gpg] https://deb.nodesource.com/node_20.x nodistro main" | tee /etc/apt/sources.list.d/nodesource.list && \
+    apt-get update && apt-get install -y nodejs && \
+    rm -rf /var/lib/apt/lists/* && \
+    npm install -g npm@latest && \
+    npm install -g apify-cli && \
+    npm cache clean --force
+
+# Create directories and set permissions
 WORKDIR /app
 
-RUN mkdir -p /tmp/runtime-root && \
-    chmod 0700 /tmp/runtime-root && \
-    chown -R appuser:appuser /tmp/runtime-root /app
+# Copy actor files
+COPY --chown=1000:1000 .actor/ .actor/
 
-COPY --chown=appuser:appuser .actor/ .actor/
-COPY --chown=appuser:appuser . .
-
-USER appuser
-
-# Set environment variables for better resource management
-ENV PYTHONUNBUFFERED=1
-ENV MALLOC_ARENA_MAX=2
-ENV EASYOCR_DOWNLOAD_CACHE="/tmp/easyocr"
-
-# Create cache directory for EasyOCR
-RUN mkdir -p /tmp/easyocr && \
-    chown -R appuser:appuser /tmp/easyocr
+# Security best practice: run as non-root user (docling-serve already uses a non-root user)
+USER 1000
 
 ENTRYPOINT [".actor/actor.sh"]

.actor/README.md

@@ -17,14 +17,14 @@ This Actor (specification v1) wraps the [Docling project](https://ds4sd.github.i
 5. [Performance & Resources](#performance--resources)
 6. [Troubleshooting](#troubleshooting)
 7. [Local Development](#local-development)
-8. [Requirements & Installation](#requirements--installation)
+8. [Architecture](#architecture)
 9. [License](#license)
 10. [Acknowledgments](#acknowledgments)
 11. [Security Considerations](#security-considerations)
 
 ## Features
 
-- Runs Docling v2.17.0 in a fully managed environment on Apify
+- Leverages the lightweight docling-serve API for efficient document processing
 - Processes multiple document formats:
   - PDF documents (scanned or digital)
   - Microsoft Office files (DOCX, XLSX, PPTX)
@@ -169,11 +169,10 @@ Content of section 2...
 
 The Actor maintains detailed processing logs including:
 
-- Memory usage statistics
+- API request and response details
 - Processing steps and timing
 - Error messages and stack traces
 - Input validation results
-- OCR processing details (when enabled)
 
 Access logs via:
 
@@ -183,18 +182,14 @@ apify key-value-stores get-record DOCLING_LOG
 
 ## Performance & Resources
 
-- **Docker Image Size**: ~6 GB (includes OCR libraries and ML models)
+- **Docker Image Size**: ~600 MB
 - **Memory Requirements**:
-  - Minimum: 4 GB RAM
-  - Recommended: 8 GB RAM for large documents
-- **Memory Monitoring**:
-  - Real-time memory usage tracking during processing
-  - Detailed memory statistics in `DOCLING_LOG`
-  - Automatic failure detection for out-of-memory situations
+  - Minimum: 2 GB RAM
+  - Recommended: 4 GB RAM for large or complex documents
 - **Processing Time**:
-  - Simple documents: 30-60 seconds
-  - Complex PDFs with OCR: 2-5 minutes
-  - Large documents (100+ pages): 5-15 minutes
+  - Simple documents: 15-30 seconds
+  - Complex PDFs with OCR: 1-3 minutes
+  - Large documents (100+ pages): 3-10 minutes
 
 ## Troubleshooting
 
@@ -210,10 +205,10 @@ Common issues and solutions:
    - Check if the image quality is sufficient
    - Try processing with OCR disabled
 
-3. **Memory Issues**
-   - For large documents, try splitting them into smaller chunks
-   - Consider using a higher-memory compute unit
-   - Disable OCR if not strictly necessary
+3. **API Response Issues**
+   - Check the logs for detailed error messages
+   - Ensure the document format is supported
+   - Verify the URL is correctly formatted
 
 4. **Output Format Issues**
    - Verify the output format is supported
@@ -227,7 +222,6 @@ The Actor implements comprehensive error handling:
 - Input validation for document URLs and parameters
 - Detailed error messages in `DOCLING_LOG`
 - Proper exit codes for different failure scenarios
-- Memory monitoring and out-of-memory detection
 - Automatic cleanup on failure
 - Dataset records with processing status
 
@@ -242,7 +236,6 @@ If you wish to develop or modify this Actor locally:
    - `actor.json` - Actor configuration and metadata
    - `actor.sh` - Main execution script
    - `input_schema.json` - Input parameter definitions
-   - `.dockerignore` - Build optimization rules
 4. Run the Actor locally using:
 
    ```bash
@@ -257,30 +250,24 @@ If you wish to develop or modify this Actor locally:
 ├── actor.json          # Actor metadata
 ├── actor.sh            # Execution script
 ├── input_schema.json   # Input parameters
-├── .dockerignore       # Build exclusions
 └── README.md           # This documentation
 ```
 
-## Requirements & Installation
+## Architecture
 
-- An [Apify account](https://console.apify.com/?fpr=docling) (free tier available)
-- For local development:
-  - Docker installed
-  - Apify CLI (`npm install -g apify-cli`)
-  - Git for version control
-- The Actor's Docker image (~6 GB) includes:
-  - Python 3.11 with optimized caching (.pyc, .pyo excluded)
-  - Node.js 20.x
-  - Docling v2.17.0 and its dependencies
-  - OCR libraries and ML models
+This Actor uses a lightweight architecture based on the official `ds4sd/docling-serve` Docker image:
 
-### Build Optimizations
-
-The Actor uses several optimizations to maintain efficiency:
-
-- Python cache files (`pycache`, `.pyc`, `.pyo`, `.pyd`) are excluded
-- Development artifacts (`.git`, `.env`, `.venv`) are ignored
-- Log and test files (`*.log`, `.pytest_cache`, `.coverage`) are excluded from builds
+- **Base Image**: `ds4sd/docling-serve:latest` (~600MB)
+- **API Communication**: Uses the RESTful API provided by docling-serve on port 8080
+- **Request Flow**:
+  1. Actor receives the input parameters
+  2. Creates a JSON payload for the docling-serve API
+  3. Makes a POST request to the /convert endpoint
+  4. Processes the response and stores it in the key-value store
+- **Dependencies**: 
+  - Node.js for Apify CLI
+  - Essential Linux tools (curl, jq, etc.)
+- **Security**: Runs as a non-root user for enhanced security
 
 ## License
 
@@ -288,12 +275,12 @@ This wrapper project is under the MIT License, matching the original Docling lic
 
 ## Acknowledgments
 
-- [Docling](https://ds4sd.github.io/docling/) codebase by IBM
+- [Docling](https://ds4sd.github.io/docling/) and [docling-serve](https://github.com/DS4SD/docling-serve) by IBM
 - [Apify](https://apify.com/?fpr=docling) for the serverless actor environment
 
 ## Security Considerations
 
-- Actor runs under a non-root user (appuser) for enhanced security
+- Actor runs under a non-root user for enhanced security
 - Input URLs are validated before processing
 - Temporary files are securely managed and cleaned up
 - Process isolation through Docker containerization

.actor/actor.sh

@@ -17,13 +17,13 @@ exec 2> >(tee -a "$LOG_FILE" >&2)
 trap 'echo "Error on line $LINENO"' ERR
 set -e
 
-# --- Validate Docling installation ---
+# --- Define error codes ---
 
-# Check if Docling CLI is installed and in PATH.
-if ! command -v docling &>/dev/null; then
-    echo "Error: Docling CLI is not installed or not in PATH"
-    exit 1
-fi
+readonly ERR_INVALID_INPUT=10
+readonly ERR_URL_INACCESSIBLE=11
+readonly ERR_DOCLING_FAILED=12
+readonly ERR_OUTPUT_MISSING=13
+readonly ERR_STORAGE_FAILED=14
 
 # --- Input parsing ---
 
@@ -36,24 +36,10 @@ INPUT="$(apify actor:get-input || {
 
 DOCUMENT_URL="$(echo "${INPUT}" | jq -r '.documentUrl')"
 OUTPUT_FORMAT="$(echo "${INPUT}" | jq -r '.outputFormat')"
-OUTPUT_NAME="output_file.${OUTPUT_FORMAT}"
-
-# Define error codes.
-readonly ERR_INVALID_INPUT=10
-readonly ERR_URL_INACCESSIBLE=11
-readonly ERR_DOCLING_FAILED=12
-readonly ERR_OUTPUT_MISSING=13
-readonly ERR_STORAGE_FAILED=14
-
-# Update error handling with codes.
-if [ -z "$DOCUMENT_URL" ]; then
-    echo "Error: Missing document URL. Please provide 'documentUrl' in the input"
-    apify actor:push-data "{\"url\": \"${DOCUMENT_URL}\", \"status\": \"error\", \"error\": \"Missing document URL\"}" || true
-    exit $ERR_INVALID_INPUT
-fi
+OCR_ENABLED="$(echo "${INPUT}" | jq -r '.ocr')"
 
 # If no output format is specified, default to 'md'.
-if [ -z "$OUTPUT_FORMAT" ]; then
+if [ -z "$OUTPUT_FORMAT" ] || [ "$OUTPUT_FORMAT" = "null" ]; then
     OUTPUT_FORMAT="md"
     echo "No output format specified. Defaulting to 'md'"
 fi
@@ -62,10 +48,20 @@ fi
 case "$OUTPUT_FORMAT" in md | json | html | text | doctags) ;;
 *)
     echo "Error: Invalid output format '$OUTPUT_FORMAT'. Supported formats are 'md', 'json', 'html', 'text', and 'doctags'"
-    exit 1
+    apify actor:push-data "{\"url\": \"${DOCUMENT_URL}\", \"status\": \"error\", \"error\": \"Invalid output format\"}" || true
+    exit $ERR_INVALID_INPUT
     ;;
 esac
 
+# Set output filename based on format.
+OUTPUT_NAME="output_file.${OUTPUT_FORMAT}"
+
+if [ -z "$DOCUMENT_URL" ] || [ "$DOCUMENT_URL" = "null" ]; then
+    echo "Error: Missing document URL. Please provide 'documentUrl' in the input"
+    apify actor:push-data "{\"status\": \"error\", \"error\": \"Missing document URL\"}" || true
+    exit $ERR_INVALID_INPUT
+fi
+
 # Validate URL is accessible.
 echo "Validating document URL..."
 if ! curl --output /dev/null --silent --head --fail "${DOCUMENT_URL}"; then
@@ -75,65 +71,81 @@ if ! curl --output /dev/null --silent --head --fail "${DOCUMENT_URL}"; then
     exit $ERR_URL_INACCESSIBLE
 fi
 
-# --- Build Docling command ---
+# --- Create JSON payload for docling-serve API ---
 
-DOC_CONVERT_CMD="docling --verbose '${DOCUMENT_URL}' --to '${OUTPUT_FORMAT}'"
+echo "Creating API request for docling-serve..."
 
-# If OCR is enabled, add the OCR flag to the command.
-if [ "$(echo "${INPUT}" | jq -r '.ocr')" = "true" ]; then
-    DOC_CONVERT_CMD="${DOC_CONVERT_CMD} --ocr"
+# Set OCR flag.
+if [ "$OCR_ENABLED" = "true" ]; then
+    OCR_VALUE="true"
+else
+    OCR_VALUE="false"
 fi
 
-# Print the exact command that will be executed.
-echo "Debug: Command string: $DOC_CONVERT_CMD"
-echo "Debug: Full command: /usr/bin/time -v bash -c \"$DOC_CONVERT_CMD\""
-
-# --- Process document with Docling ---
-
-echo "Processing document with Docling CLI..."
-echo "Running: $DOC_CONVERT_CMD"
-
-# Create a timestamp file to ensure the document is processed only once.
-TIMESTAMP_FILE="/tmp/docling.timestamp"
-touch "$TIMESTAMP_FILE" || {
-    echo "Error: Failed to create timestamp file"
-    exit 1
+# Create a temporary file for the JSON payload.
+REQUEST_FILE="/tmp/docling_request.json"
+cat > "$REQUEST_FILE" << EOF
+{
+    "document_url": "${DOCUMENT_URL}",
+    "output_format": "${OUTPUT_FORMAT}",
+    "ocr": ${OCR_VALUE}
 }
+EOF
 
-echo "Starting document processing with memory monitoring..."
-/usr/bin/time -v bash -c "${DOC_CONVERT_CMD}" 2>&1 | tee -a "$LOG_FILE"
-DOCLING_EXIT_CODE=${PIPESTATUS[0]}
+echo "Request payload:"
+cat "$REQUEST_FILE"
 
-# Check if the command failed and handle the error.
-if [ $DOCLING_EXIT_CODE -ne 0 ]; then
-    echo "Error: Docling command failed with exit code $DOCLING_EXIT_CODE"
-    echo "Memory usage information:"
-    free -h
-    df -h
+# --- Call docling-serve API ---
+
+echo "Calling docling-serve API (localhost:8080/convert)..."
+
+RESPONSE_FILE="/tmp/docling_response.json"
+HTTP_CODE=$(curl -s -o "$RESPONSE_FILE" -w "%{http_code}" -X POST \
+    -H "Content-Type: application/json" \
+    -d @"$REQUEST_FILE" \
+    http://localhost:8080/convert)
+
+echo "API Response Status Code: $HTTP_CODE"
+
+# Check response status code.
+if [ "$HTTP_CODE" -ne 200 ]; then
+    echo "Error: docling-serve API returned error code $HTTP_CODE"
+    if [ -f "$RESPONSE_FILE" ]; then
+        echo "Error response:"
+        cat "$RESPONSE_FILE"
+    fi
+
+    ERROR_MSG=$(jq -r '.error // "Unknown API error"' "$RESPONSE_FILE" 2>/dev/null || echo "Unknown API error")
+
+    apify actor:push-data "{\"url\": \"${DOCUMENT_URL}\", \"status\": \"error\", \"error\": \"${ERROR_MSG}\"}" || true
     exit $ERR_DOCLING_FAILED
 fi
 
-GENERATED_FILE="$(find . -type f -name "*.${OUTPUT_FORMAT}" -newer "$TIMESTAMP_FILE")"
+# --- Process API response ---
 
-# If no generated file is found, exit with an error.
-if [ -z "$GENERATED_FILE" ]; then
-    echo "Error: Could not find generated output file with extension .$OUTPUT_FORMAT"
+echo "Processing API response..."
+
+# Extract content from response and save to output file.
+if ! jq -r '.content' "$RESPONSE_FILE" > "$OUTPUT_NAME" 2>/dev/null; then
+    echo "Error: Failed to parse API response or extract content"
+    echo "Response content:"
+    cat "$RESPONSE_FILE"
+
+    apify actor:push-data "{\"url\": \"${DOCUMENT_URL}\", \"status\": \"error\", \"error\": \"Failed to parse API response\"}" || true
     exit $ERR_OUTPUT_MISSING
 fi
 
-mv "${GENERATED_FILE}" "${OUTPUT_NAME}"
-
-# --- Validate output ---
-
-# If the output file is not found, exit with an error.
+# Validate output file.
 if [ ! -f "$OUTPUT_NAME" ]; then
-    echo "Error: Expected output file '$OUTPUT_NAME' was not generated"
+    echo "Error: Output file was not created"
+    apify actor:push-data "{\"url\": \"${DOCUMENT_URL}\", \"status\": \"error\", \"error\": \"Output file not created\"}" || true
     exit $ERR_OUTPUT_MISSING
 fi
 
-# If the output file is empty, exit with an error.
+# Validate output file is not empty.
 if [ ! -s "$OUTPUT_NAME" ]; then
-    echo "Error: Generated output file '$OUTPUT_NAME' is empty"
+    echo "Error: Output file is empty"
+    apify actor:push-data "{\"url\": \"${DOCUMENT_URL}\", \"status\": \"error\", \"error\": \"Output file is empty\"}" || true
     exit $ERR_OUTPUT_MISSING
 fi
 
@@ -142,7 +154,18 @@ echo "Document successfully processed and exported as '$OUTPUT_FORMAT' to file:
 # --- Store output and log in key-value store ---
 
 echo "Pushing processed document to key-value store (record key: OUTPUT_RESULT)..."
-apify actor:set-value "OUTPUT_RESULT" --contentType "application/$OUTPUT_FORMAT" <"$OUTPUT_NAME" || {
+
+CONTENT_TYPE=""
+case "$OUTPUT_FORMAT" in
+    md)      CONTENT_TYPE="text/markdown" ;;
+    json)    CONTENT_TYPE="application/json" ;;
+    html)    CONTENT_TYPE="text/html" ;;
+    text)    CONTENT_TYPE="text/plain" ;;
+    doctags) CONTENT_TYPE="application/json" ;;
+    *)       CONTENT_TYPE="text/plain" ;;
+esac
+
+apify actor:set-value "OUTPUT_RESULT" --contentType "$CONTENT_TYPE" < "$OUTPUT_NAME" || {
     echo "Error: Failed to push the output document to the key-value store"
     exit $ERR_STORAGE_FAILED
 }
@@ -154,24 +177,19 @@ apify actor:push-data "{\"url\": \"${DOCUMENT_URL}\", \"output_file\": \"${RESUL
     echo "Warning: Failed to push data to dataset"
 }
 
-if [ -f "$LOG_FILE" ]; then
-    if [ -s "$LOG_FILE" ]; then
-        echo "Log file is not empty, pushing to key-value store (record key: DOCLING_LOG)..."
+# Store logs.
+if [ -f "$LOG_FILE" ] && [ -s "$LOG_FILE" ]; then
+    echo "Pushing log file to key-value store (record key: DOCLING_LOG)..."
     apify actor:set-value "DOCLING_LOG" --contentType "text/plain" < "$LOG_FILE" || {
         echo "Warning: Failed to push the log file to the key-value store"
     }
-    else
-        echo "Warning: docling.log file exists but is empty"
-    fi
-else
-    echo "Warning: No docling.log file found"
 fi
 
 # --- Cleanup temporary files ---
 
 cleanup() {
     local exit_code=$?
-    rm -f "$TIMESTAMP_FILE" || true
+    rm -f "$REQUEST_FILE" "$RESPONSE_FILE" || true
     exit $exit_code
 }
 

.actor/input_schema.json

@@ -1,20 +1,20 @@
 {
   "title": "Docling Actor Input",
-  "description": "Options for running Docling CLI on the Apify platform.",
+  "description": "Options for processing documents with Docling via the docling-serve API.",
   "type": "object",
   "schemaVersion": 1,
   "properties": {
     "documentUrl": {
       "title": "Document URL",
       "type": "string",
-      "description": "URL of the document to process with Docling. Supported formats: images, 'pdf', 'docx', 'pptx', 'xlsx, 'html', 'md', 'xml_pubmed', 'asciidoc', 'xml_uspto'.",
+      "description": "URL of the document to process. Supported formats: PDF, DOCX, PPTX, XLSX, HTML, MD, XML, images, and more.",
       "prefill": "https://arxiv.org/pdf/2408.09869.pdf",
       "editor": "textfield"
     },
     "outputFormat": {
       "title": "Output Format",
       "type": "string",
-      "description": "Specifies the desired output format after processing the document. Supported formats: 'md', 'json', 'html', 'text', 'doctags'.",
+      "description": "Desired output format after processing the document.",
       "enum": ["md", "json", "html", "text", "doctags"],
       "default": "md",
       "editor": "select"
@@ -22,7 +22,7 @@
     "ocr": {
       "title": "Enable OCR",
       "type": "boolean",
-      "description": "If true, OCR will be applied to scanned PDFs for text recognition.",
+      "description": "If enabled, OCR will be applied to scanned documents for text recognition.",
       "default": true
     }
   },