History

3.0.0 (2026-07-27)

3.0.0 is the compatibility release: the one release the roadmap allows to change behaviour and drop dependencies, closing out the standards-conformance work (PROV-DM, PROV-CONSTRAINTS, PROV-O) that a backward-compatible 2.x series could not fix. See Upgrading to 3.0 for what changed and what to do about it.

Breaking changes

• ProvBundle.unified() / ProvDocument.unified() implement PROV-CONSTRAINTS key constraints (22/23) with pairwise term unification of formal attributes: records sharing an identifier whose formal attributes hold different concrete values now raise the new documented prov.model.ProvUnificationError instead of silently unioning; absent formal attributes unify with concrete values; extra attributes keep set-union semantics; bundles unify independently (#253)

• unified() rejects same-identifier records of incompatible types (entity vs activity, distinct relation kinds — PROV-CONSTRAINTS 53/54/55) with ProvUnificationError instead of merging them order-dependently into the first record’s type; spec-permitted overlaps (an agent that is also an entity or activity) are kept as separate records (#253)

• Attribute values that are Python-equal but differently typed (2 vs 2.0, 1 vs True) are all retained on a record instead of collapsing to whichever was asserted first — visible in attribute iteration, record equality and hashing, and serialization. Attributes now iterate in assertion order rather than an arbitrary hash order, which makes args, formal_attributes, get_startTime() and get_endTime() deterministic. ProvRecord.get_attribute(), get_asserted_types() and the value property still return a plain set, but it is now built fresh on every call, so mutating it no longer writes through to the record: record.get_asserted_types().add(qn) now silently does nothing (#34)

• pydot and networkx are no longer unconditional runtime dependencies. import prov.dot now requires the dot extra (pip install "prov[dot]") and import prov.graph the graph extra; without them the import raises ModuleNotFoundError naming the extra to install. The plot extra now pulls in pydot/networkx as well, since plot() renders through prov.dot. See docs/upgrading-3.0.md.

• The rdf extra now requires rdflib>=7.0.0 (previously >=6.0.0); round-trip behaviour is unchanged

• python-dateutil dropped — prov now has no unconditional runtime dependencies. Datetime strings are parsed as xsd:dateTime (ISO 8601 plus the hour-24 end-of-day form) via the standard library; factory time=/startTime=/endTime= parameters raise ProvException on invalid input instead of leaking a raw dateutil error, and non-ISO forms previously tolerated by dateutil (e.g. "Nov 7, 2011") are no longer accepted (#237)

• The misspelled prov.model.GenrationRef type alias is renamed GenerationRef; the old spelling is removed rather than kept as a deprecated alias

Conformance and correctness fixes

• When an attribute is asserted twice with an equal value of equal type — e.g. Literal("10", XSD_DECIMAL) and Literal("10.00", XSD_DECIMAL) (#77), or Literal("hi", langtag="en") and Literal("hi", langtag="EN") (#259) — the record retains the first value asserted, as in 2.x (#34)

• Numeric datatype fidelity: Literal values typed xsd:long (and the rest of the XSD integer family) keep their asserted datatype instead of being silently re-typed xsd:int (#235); PROV-N output types plain integers by magnitude (xsd:int/xsd:long/xsd:integer) so out-of-int32 values are no longer emitted as invalid bare int literals (#249), and plain floats as full-precision xsd:double instead of %g-truncated xsd:float (#251)

• Literal semantics: string literals have one canonical serialized form (RDF output no longer decorates plain strings with ^^xsd:string) (#89); xsd:decimal literals compare and hash in value space (#77); language tags compare case-insensitively per RDF 1.1 while preserving their original case in output (#259)

• PROV-XML round trip preserves attributes whose value is the empty string; previously they were silently dropped on deserialization (#224)

• PROV-XML serializes attribute names containing characters illegal in an XML NCName using the reversible _xHHHH_ escaping convention instead of raising ValueError; the deserializer applies the inverse, so such names round-trip (#289)

• The PROV-JSON deserializer raises ProvJSONException on structurally malformed input instead of leaking raw KeyError/AttributeError (#228)

• PROV-JSON typed literals always encode $ as a string, and plain integers are typed by magnitude across PROV-JSON/PROV-XML/PROV-O output (xsd:int/xsd:long/xsd:integer), fixing schema-invalid output for out-of-int32 values (#244, #246, #256)

• PROV-JSON encodes QualifiedName attribute values as xsd:QName typed literals per the PROV-JSON submission (previously the non-standard prov:QUALIFIED_NAME, which remains accepted on input) (#168), and prov:QUALIFIED_NAME-typed Literal values are resolved to QualifiedNames at assertion time, restoring round-trip equality (#238)

• PROV-O: documents containing multiple same-identifier relations with differing formal attributes (“scruffy” statements) are documented as a PROV-O representational limitation — they serialize but do not round-trip through RDF, and deserializing such RDF now raises an error naming the limitation; all other formats are unaffected (#217)

• PROV-O: a related gap is recorded, not fixed — an attribute key whose local part ends in a PROV-N metacharacter (#223) can fail to round-trip through RDF when its namespace has not already been registered by another qualified name; docs/reference/conformance.md documents it as an open defect (#341)

• PROV-O (RDF) round-trip fidelity: mixed XSD-datatype attribute sets survive deserialization with their asserted datatypes intact (#218), and xsd:double values are emitted at full precision instead of rdflib’s 6-significant-digit canonical form (#225)

• PROV-O output: anonymous qualified Communication/Attribution/Delegation/ Influence nodes now carry their influencer property (prov:activity/ prov:agent/prov:agent/prov:influencer) as the PROV-O qualification tables require, and the RDF round trip no longer collapses distinct anonymous delegations sharing a (delegate, activity) pair (#250, #226)

• PROV-O output emits alternateOf with the PROV-DM argument order (alt1 prov:alternateOf alt2); previously subject and object were transposed on both write and read (#258)

• PROV-O (RDF) deserialization returns xsd:base64Binary literals as their base64 text; previously the value was wrapped in a Python bytes repr (b'…'), corrupting the round trip (#288)

• PROV-O (RDF) deserialization reconciles prov:startedAtTime/ prov:endedAtTime asserted directly on a qualified prov:Start/ prov:End node into the relation’s formal prov:time attribute; previously the formal attribute was left None and the value misfiled as an extra attribute (#299)

• PROV-O (RDF) round trip: an anonymous Communication/Attribution/Influence relation carrying extra attributes now deserializes back into a single record instead of two (#303)

• PROV-O (RDF) round trip: a qualified name whose local part ends in a PROV-N metacharacter (= ' , : ; [ ]) now deserializes instead of raising ValueError: Can't split ...; serialized output is unchanged (#294)

• PROV-N output escapes qualified-name local parts per the grammar’s PN_CHARS_ESC production, so identifiers containing ' ( ) , : ; [ ] = no longer produce invalid PROV-N (#223)

• PROV-N continues to emit Mention as bare mentionOf(...) — the de-facto syntax of the reference implementations for the last decade — rather than the prov:mentionOf form derivable from the PROV-Links note; now documented as a deliberate deviation (#248)

Improvements

• Bundle-local and default namespace prefixes are now bound into RDF serialization alongside document-level ones, so turtle/TriG output uses the declared prefixes instead of auto-minted ns1:-style fallbacks (#96)

• Security: PROV-XML parsing no longer resolves DTD entities and never touches the network (resolve_entities=False, no_network=True), closing an XXE surface on untrusted input (#273)

• New public type aliases in prov.model, joining the existing NameValuePair: AttributePair (an attribute name/value pair before qualified-name resolution), InfluencerRef (the influencer parameter of wasInfluencedBy() and influence()) and StreamOrPath (the source and destination parameters of read(), serialize() and deserialize())

Internal

• The PROV-O (RDF) serializer’s encode/decode container functions were decomposed into per-record-type dispatch, with byte-identical output (#274)

• Functions across the model, the serializers and prov.dot were refactored below the project’s complexity threshold, with byte-identical behaviour (#275)

• Code-quality passes across src/prov/ — type-alias adoption, removal of a permanently-disabled branch in the PROV-O (RDF) encoder, and readability clean-ups — with no change in behaviour

• Test infrastructure: the RDF fixture-comparison helper find_diff() now detects single-triple differences, which it previously missed (#304)

2.5.1 (2026-07-13)

• prov.read() polish following 2.5.0’s #239: seekable streams are now rewound between auto-detection attempts (so e.g. a PROV-XML stream auto-detects instead of being consumed by the first candidate); rdflib’s “does not look like a valid URI” logger noise from swallowed candidate attempts is suppressed during auto-detection; and when a str/bytes source that is not an existing file path fails to parse, the error now carries a hint that it was treated as raw content

• Documentation: the PROV-XML and PROV-JSON how-to pages no longer describe the pre-2.5.0 read() auto-detection behaviour (exception whitelist, “XML never auto-detects”)

2.5.0 (2026-07-13)

• New record-level chaining convenience methods (#154): ProvEntity.wasRevisionOf(), .wasQuotedFrom(), .hadPrimarySource(), .mentionOf(), and .wasInfluencedBy() on ProvEntity, ProvActivity and ProvAgent — mirroring the existing e1.wasDerivedFrom(e2) style for the remaining relation types

• The PROV-XML deserializer now raises ProvXMLException when a record’s child element carries only unrecognised XML attributes, instead of leaking a raw UnboundLocalError or silently reusing the previous attribute’s value (#254)

• ProvDocument.serialize() and deserialize() now accept any writable/ readable file-like object (e.g. tempfile.NamedTemporaryFile), instead of only io.IOBase instances; previously such destinations were silently treated as file paths, writing to a repr-named file in the working directory. The serializers’ text/binary stream detection now also recognises such wrapper objects as text streams (#240)

• prov.read() fixes (#239): valid PROV-XML is now auto-detected (the RDF parser’s BadSyntax no longer aborts detection); a str/bytes source that is not an existing file path is parsed as raw content, as the documentation always advertised; and input that no deserializer can meaningfully parse (e.g. an empty file) now raises TypeError instead of silently returning an empty document

• Documentation: the agent-subtype idiom now correctly uses qualified names (PROV["Person"]) for prov:type values; the previously documented string form asserted a plain string, which does not denote the pre-defined PROV type (#236)

2.4.0 (2026-07-06)

• Documentation overhaul: the documentation has been reorganised along the Diátaxis framework (tutorials, how-to guides, reference, explanations), with new furo/MyST/napoleon/intersphinx tooling behind the Sphinx build. Closes #141 (graphics export how-to) and #83 (prov-convert/prov-compare CLI tools how-to). (#210, #211, #212, #213, #214, #215, #216)

• Test suite redesigned as pytest-native: shared statement/attribute/qname coverage is now expressed once and parametrized across a document x format matrix (json/xml/rdf/model) instead of being copy-pasted per serializer; Hypothesis property-based round-trip tests generate documents across the full feature set; a malformed-input corpus exercises each deserializer’s error handling. (#219, #220, #221, #222, #227, #229)

• ``prov.model`` split into a package (prov.model.records, prov.model.namespaces, prov.model.bundle) for maintainability, with no import-path changes: every historic from prov.model import X still works identically. (#231)

• Minor Makefile/CLAUDE.md cleanup for contributors. (#209)

• The serializer registry now degrades gracefully when the optional rdf (rdflib) or xml (lxml) extra is not installed: import prov and the JSON/PROV-N serializers work in a minimal install, and requesting the rdf/xml format raises an informative DoNotExist naming the missing extra instead of a bare ModuleNotFoundError. (#230)

• Deprecation warnings signposting planned 3.0 changes: importing prov.dot/prov.graph now emits a DeprecationWarning naming the future prov[dot]/prov[graph] extras those modules will require, and ProvBundle.unified()/ProvDocument.unified() emit a FutureWarning about the upcoming PROV-CONSTRAINTS unification rework. Both warnings are hidden by default (standard DeprecationWarning/FutureWarning semantics) and link to the new Upgrading to 3.0 guide, which tables every planned 3.0 change and what to do about it.

2.3.0 (2026-07-05)

• Dropped Python 3.9 support; minimum is now Python 3.10 (security fixes in transitive dependencies are only released for Python 3.10+) (#189)

• Widened ``rdflib`` to ``>=6.0.0,<8`` (was >=4.2.1,<7): rdflib 7 now supported; the floor rose because 4.2.1 no longer installs on supported Pythons (#207)

• Diagnostic improvement: DoNotExist (serializer lookup) and the CLI’s CLIError now set __cause__ via exception chaining, so tracebacks show the original error; exception types and messages are unchanged, so existing except blocks are unaffected (#200)

• Whole package passes mypy --strict; ships a py.typed marker (PEP 561) so downstream type-checkers see inline types (#192, #193, #194)

• Coverage raised to 97%, enforced in CI; new tests for the CLI scripts, prov.read() auto-detection, graph interop, and the serializer registry (#201, #202, #203, #204)

• Internal code quality: ruff rule families I/C4/SIM/RUF/UP045/UP031 enabled and long-standing lint suppressions resolved (#195, #196, #197, #198, #199, #200); dependency audit documented in docs/dependencies.md; tox removed (use uv run --python 3.X pytest for local multi-version testing) (#205)

• Security hygiene: SECURITY.md, Dependabot version updates, and a documented support policy (#190)

• Fixed ReadTheDocs build (Sphinx pinned <9) (#187)

2.2.0 (2026-07-03)

• Fixed graphical output when a filename is supplied (#164)

• Fixed PROV-XML deserialization when prov is the default namespace (#155)

• New plot extra: pip install prov[plot] for matplotlib support (#166)

• Marked as Production/Stable; added Python 3.14 to the test matrix

• Tooling: ruff (lint+format), pytest runner, uv-based CI, automated PyPI releases via Trusted Publishing. No public API changes.

2.1.1 (2025-06-24)

• No change - fixing the previous botched release

2.1.0 (2025-06-24)

• Added type annotations and mypy checks

• Added support for Python 3.13

2.0.2 (2025-06-07)

• Removed support for EOL Python 3.8

• Using pyproject.toml for project configurations (instead of setup.py)

2.0.1 (2024-06-10)

• Removed support for EOL Python 3.6 and 3.7

• Minor documentation update (#153)

• Stopped using deepcopy when duplicating Namespace (#158)

• Restricting rdflib package version to “<7” (#156)

• Raise an exception when an empty URI is registered as a namespace (#142)

• Ensure rdflib 6+ returns bytes when serializing tests (fixed #151)

• Removed fancy label output for bundle

2.0.0 (2020-11-01)

• Removed support for EOL Python 2

• Testing against Python 3.6+ and Pypy3

Earlier releases

Releases before 2.0.0 are recorded in the changelog archive.