integrate jsonld code into rdflib core

1 files changed, 81 insertions, 0 deletions

diff --git a/rdflib/plugins/shared/jsonld/util.py b/rdflib/plugins/shared/jsonld/util.py
new file mode 100644
index 00000000..50b34b54
--- /dev/null
+++ b/rdflib/plugins/shared/jsonld/util.py
@@ -0,0 +1,81 @@
+# -*- coding: utf-8 -*-
+# https://github.com/RDFLib/rdflib-jsonld/blob/feature/json-ld-1.1/rdflib_jsonld/util.py
+
+try:
+    import json
+
+    assert json  # workaround for pyflakes issue #13
+except ImportError:
+    import simplejson as json
+
+from os import sep
+from os.path import normpath
+
+from urllib.parse import urljoin, urlsplit, urlunsplit
+
+from rdflib.parser import create_input_source
+
+from io import StringIO
+
+
+def source_to_json(source):
+    # TODO: conneg for JSON (fix support in rdflib's URLInputSource!)
+    source = create_input_source(source, format="json-ld")
+
+    stream = source.getByteStream()
+    try:
+        return json.load(StringIO(stream.read().decode("utf-8")))
+    finally:
+        stream.close()
+
+
+VOCAB_DELIMS = ("#", "/", ":")
+
+
+def split_iri(iri):
+    for delim in VOCAB_DELIMS:
+        at = iri.rfind(delim)
+        if at > -1:
+            return iri[: at + 1], iri[at + 1 :]
+    return iri, None
+
+
+def norm_url(base, url):
+    """
+    >>> norm_url('http://example.org/', '/one')
+    'http://example.org/one'
+    >>> norm_url('http://example.org/', '/one#')
+    'http://example.org/one#'
+    >>> norm_url('http://example.org/one', 'two')
+    'http://example.org/two'
+    >>> norm_url('http://example.org/one/', 'two')
+    'http://example.org/one/two'
+    >>> norm_url('http://example.org/', 'http://example.net/one')
+    'http://example.net/one'
+    >>> norm_url('http://example.org/', 'http://example.org//one')
+    'http://example.org//one'
+    """
+    parts = urlsplit(urljoin(base, url))
+    path = normpath(parts[2])
+    if sep != "/":
+        path = "/".join(path.split(sep))
+    if parts[2].endswith("/") and not path.endswith("/"):
+        path += "/"
+    result = urlunsplit(parts[0:2] + (path,) + parts[3:])
+    if url.endswith("#") and not result.endswith("#"):
+        result += "#"
+    return result
+
+
+def context_from_urlinputsource(source):
+    if source.content_type == "application/json":
+        # response_info was added to InputSource in rdflib 4.2
+        try:
+            links = source.response_info.getallmatchingheaders("Link")
+        except AttributeError:
+            return
+        for link in links:
+            if ' rel="http://www.w3.org/ns/json-ld#context"' in link:
+                i, j = link.index("<"), link.index(">")
+                if i > -1 and j > -1:
+                    return urljoin(source.url, link[i + 1 : j])