feat: Initial version of readability extractor

archivebox/extractors/readability.py

@@ -0,0 +1,83 @@
+__package__ = 'archivebox.extractors'
+
+from pathlib import Path
+
+from typing import Optional
+import json
+
+from ..index.schema import Link, ArchiveResult, ArchiveError
+from ..system import run, atomic_write
+from ..util import (
+    enforce_types,
+    download_url,
+    
+)
+from ..config import (
+    TIMEOUT,
+    SAVE_READABILITY,
+    READABILITY_BINARY,
+    READABILITY_VERSION,
+    CHROME_BINARY,
+)
+from ..logging_util import TimedProgress
+
+
+@enforce_types
+def should_save_readability(link: Link, out_dir: Optional[str]=None) -> bool:
+    out_dir = out_dir or link.link_dir
+
+    output = Path(out_dir or link.link_dir) / 'readability.json'
+    return SAVE_READABILITY and (not output.exists())
+
+
+@enforce_types
+def save_readability(link: Link, out_dir: Optional[str]=None, timeout: int=TIMEOUT) -> ArchiveResult:
+    """download reader friendly version using @mozilla/readability"""
+
+    out_dir = out_dir or link.link_dir
+    output = str(Path(out_dir).absolute() / "readability.json")
+
+    document = download_url(link.url)
+
+    # SingleFile CLI Docs: https://github.com/gildas-lormeau/SingleFile/tree/master/cli
+    cmd = [
+        READABILITY_BINARY,
+        document
+    ]
+
+    status = 'succeeded'
+    timer = TimedProgress(timeout, prefix='      ')
+    try:
+        result = run(cmd, cwd=out_dir, timeout=timeout)
+        result_json = json.loads(result.stdout)
+        atomic_write(output, result_json)
+
+        # parse out number of files downloaded from last line of stderr:
+        #  "Downloaded: 76 files, 4.0M in 1.6s (2.52 MB/s)"
+        output_tail = [
+            line.strip()
+            for line in (result.stdout + result.stderr).decode().rsplit('\n', 3)[-3:]
+            if line.strip()
+        ]
+        hints = (
+            'Got readability response code: {}.'.format(result.returncode),
+            *output_tail,
+        )
+
+        # Check for common failure cases
+        if (result.returncode > 0):
+            raise ArchiveError('Readability was not able to archive the page', hints)
+    except Exception as err:
+        status = 'failed'
+        output = err
+    finally:
+        timer.end()
+
+    return ArchiveResult(
+        cmd=cmd,
+        pwd=out_dir,
+        cmd_version=READABILITY_VERSION,
+        output=output,
+        status=status,
+        **timer.stats,
+    )