EML Parser Library

Common errors

• ModuleNotFoundError: No module named 'eml_parser'

  cause The `eml-parser` library is not installed in your current Python environment, or the environment is not active.
  fix Run `pip install eml-parser` to install the package.

• SyntaxError: invalid syntax (some_file.py, line X)

  cause You are attempting to run `eml-parser` version 3.0.0 or higher on a Python version older than 3.10. The library uses modern Python 3.10+ typing syntax.
  fix Upgrade your Python interpreter to version 3.10 or newer. Alternatively, if you cannot upgrade Python, install an older compatible version of the library: `pip install eml-parser<3.0.0`.

• KeyError: 'subject'

  cause The expected key (e.g., 'subject', 'from') does not exist in the parsed EML header or body dictionary for the specific email being processed. This often happens with malformed or unusual EML files.
  fix Always check for the existence of keys before accessing them, especially when dealing with potentially non-standard EML files. Use `.get()` with a default value, or wrap access in a `try-except KeyError` block, or use `if key in dict:`.

Warnings

• breaking Version 3.0.0 and newer require Python 3.10 or higher. Running on older Python versions will result in `SyntaxError` or `ModuleNotFoundError` for incompatible type hints.
  Fix: Upgrade your Python environment to 3.10 or newer, or pin `eml-parser<3.0.0` if you must use an older Python version.
• breaking The typing syntax was upgraded for Python 3.10+ in v3.0.0. If you have custom code extending or directly interacting with internal types, it might require adjustments.
  Fix: Review your code for compatibility with Python 3.10+ typing syntax and update accordingly. Most basic usage should be unaffected.
• gotcha Version 2.0.0 introduced support for custom parsing policies. If your application relies on specific parsing behaviors that might have been influenced by new policy options, review if a custom policy is needed.
  Fix: Consult the official documentation for custom policy options and implement one if the default behavior no longer meets your requirements.
• gotcha Starting from v1.17.0, new validation options were added for URLs, email addresses, and IP addresses (e.g., Public Suffix List, `ip_force_routable`, `domain_force_tld`). This might cause previously parsed 'valid' items to be filtered out.
  Fix: Review the parsing options and explicitly configure `EmlParser` settings if you need to disable or fine-tune these new validation behaviors to match prior results.

Install

• pip install eml-parser Install latest version

Imports

• EmlParser

  from eml_parser import EmlParser

Quickstart

This quickstart demonstrates how to initialize the EmlParser and parse EML content from a string. The parsed data is returned as a dictionary, allowing easy access to headers, body, and other elements. An example of how to parse from a file is also included as a comment.

from eml_parser import EmlParser

eml_content = """
From: sender@example.com
To: receiver@example.com
Subject: Test Email
Date: Thu, 1 Jan 2023 12:00:00 +0000
Content-Type: text/plain; charset="utf-8"

This is a sample email body.
"""

# Initialize the parser
parser = EmlParser()

# Parse the EML content from a string
parsed_eml = parser.parse_from_string(eml_content)

# Print some extracted data
print(f"From: {parsed_eml['header']['from']}")
print(f"Subject: {parsed_eml['header']['subject']}")
if parsed_eml['body']:
    print(f"Body content: {parsed_eml['body'][0]['content']}")

# Example for parsing from a file
# with open('path/to/your.eml', 'rb') as f:
#     file_content = f.read()
#     parsed_eml_file = parser.parse_from_string(file_content.decode('utf-8', errors='ignore'))
#     print(f"File Subject: {parsed_eml_file['header']['subject']}")