---
--- Software Heritage Data Model
---
-- drop schema if exists swh cascade;
-- create schema swh;
-- set search_path to swh;
create table dbversion
(
version int primary key,
release timestamptz,
description text
);
insert into dbversion(version, release, description)
values(17, now(), 'Work In Progress');
-- a SHA1 checksum (not necessarily originating from Git)
create domain sha1 as bytea check (length(value) = 20);
-- a Git object ID, i.e., a SHA1 checksum
create domain sha1_git as bytea check (length(value) = 20);
-- a SHA256 checksum
create domain sha256 as bytea check (length(value) = 32);
-- UNIX path (absolute, relative, individual path component, etc.)
create domain unix_path as bytea;
-- a set of UNIX-like access permissions, as manipulated by, e.g., chmod
create domain file_perms as int;
create type content_status as enum ('absent', 'visible', 'hidden');
-- An origin is a place, identified by an URL, where software can be found. We
-- support different kinds of origins, e.g., git and other VCS repositories,
-- web pages that list tarballs URLs (e.g., http://www.kernel.org), indirect
-- tarball URLs (e.g., http://www.example.org/latest.tar.gz), etc. The key
-- feature of an origin is that it can be *fetched* (wget, git clone, svn
-- checkout, etc.) to retrieve all the contained software.
create table origin
(
id bigserial primary key,
type text, -- TODO use an enum here (?)
url text not null
);
-- Checksums about actual file content. Note that the content itself is not
-- stored in the DB, but on external (key-value) storage. A single checksum is
-- used as key there, but the other can be used to verify that we do not inject
-- content collisions not knowingly.
create table content
(
sha1 sha1 primary key,
sha1_git sha1_git not null,
sha256 sha256 not null,
length bigint not null,
ctime timestamptz not null default now(),
-- creation time, i.e. time of (first) injection into the storage
status content_status not null default 'visible'
);
create unique index on content(sha1_git);
create unique index on content(sha256);
-- Content we have seen but skipped for some reason. This table is
-- separate from the content table as we might not have the sha1
-- checksum of that data (for instance when we inject git
-- repositories, objects that are too big will be skipped here, and we
-- will only know their sha1_git). 'reason' contains the reason the
-- content was skipped. origin is a nullable column allowing to find
-- out which origin contains that skipped content.
create table skipped_content
(
sha1 sha1,
sha1_git sha1_git,
sha256 sha256,
length bigint not null,
ctime timestamptz not null default now(),
status content_status not null default 'absent',
reason text not null,
origin bigint references origin(id),
unique (sha1, sha1_git, sha256)
);
-- those indexes support multiple NULL values.
create unique index on skipped_content(sha1);
create unique index on skipped_content(sha1_git);
create unique index on skipped_content(sha256);
-- An organization (or part thereof) that might be in charge of running
-- software projects. Examples: Debian, GNU, GitHub, Apache, The Linux
-- Foundation. The data model is hierarchical (via parent_id) and might store
-- sub-branches of existing organizations. The key feature of an organization
-- is that it can be *listed* to retrieve information about its content, i.e:
-- sub-organizations, projects, origins.
create table organization
(
id bigserial primary key,
parent_id bigint references organization(id),
name text not null,
description text,
homepage text,
list_engine text, -- crawler to be used to org's content
list_url text, -- root URL to start the listing
list_params json, -- org-specific listing parameter
latest_list timestamptz -- last time the org's content has been listed
);
-- Log of all organization listings (i.e., organization crawling) that have
-- been done in the past, or are still ongoing. Similar to fetch_history, but
-- for organizations.
create table list_history
(
id bigserial primary key,
organization bigint references organization(id),
date timestamptz not null,
status boolean, -- true if and only if the listing has been successful
result json, -- more detailed return value, depending on status
stdout text,
stderr text,
duration interval -- fetch duration of NULL if still ongoing
);
-- Log of all origin fetches (i.e., origin crawling) that have been done in the
-- past, or are still ongoing. Similar to list_history, but for origins.
create table fetch_history
(
id bigserial primary key,
origin bigint references origin(id),
date timestamptz not null,
status boolean, -- true if and only if the fetch has been successful
result json, -- more detailed returned values, times, etc...
stdout text,
stderr text, -- null when status is true, filled otherwise
duration interval -- fetch duration of NULL if still ongoing
);
-- A specific software project, e.g., the Linux kernel, Apache httpd. A
-- software project is version-less at this level, but is associated to several
-- metadata. Metadata can evolve over time, this table only contains the most
-- recent version of them; for old versions of project see table
-- project_history.
create table project
(
id bigserial primary key,
organization bigint references organization(id), -- the "owning" organization
origin bigint references origin(id), -- where to find project releases
name text,
description text,
homepage text,
doap jsonb
-- other kinds of metadata/software project description ontologies can be
-- added here, in addition to DOAP
);
-- History of project metadata. Time-sensitive version of the table project.
create table project_history
(
id bigserial primary key,
project bigint references project(id),
validity tstzrange,
organization bigint references organization(id),
origin bigint references origin(id),
name text,
description text,
homepage text,
doap jsonb
);
-- A file-system directory. A directory is a list of directory entries (see
-- tables: directory_entry_{dir,file}).
--
-- To list the contents of a directory:
-- 1. list the contained directory_entry_dir using array dir_entries
-- 2. list the contained directory_entry_file using array file_entries
-- 3. list the contained directory_entry_rev using array rev_entries
-- 4. UNION
--
-- Synonyms/mappings:
-- * git: tree
create table directory
(
id sha1_git primary key,
dir_entries bigint[], -- sub-directories, reference directory_entry_dir
file_entries bigint[], -- contained files, reference directory_entry_file
rev_entries bigint[] -- mounted revisions, reference directory_entry_rev
);
create index on directory using gin (dir_entries);
create index on directory using gin (file_entries);
create index on directory using gin (rev_entries);
-- A directory entry pointing to a sub-directory.
create table directory_entry_dir
(
id bigserial primary key,
target sha1_git, -- references directory(id) deferrable initially deferred,
-- id of target directory
name unix_path, -- path name, relative to containing dir
perms file_perms, -- unix-like permissions
atime timestamptz, -- time of last access
mtime timestamptz, -- time of last modification
ctime timestamptz -- time of last status change
);
create unique index on directory_entry_dir(target, name, perms, atime, mtime, ctime);
create unique index on directory_entry_dir(target, name, perms)
where atime is null and mtime is null and ctime is null;
-- A directory entry pointing to a file.
create table directory_entry_file
(
id bigserial primary key,
target sha1_git, -- id of target file
name unix_path, -- path name, relative to containing dir
perms file_perms, -- unix-like permissions
atime timestamptz, -- time of last access
mtime timestamptz, -- time of last modification
ctime timestamptz -- time of last status change
);
create unique index on directory_entry_file(target, name, perms, atime, mtime, ctime);
create unique index on directory_entry_file(target, name, perms)
where atime is null and mtime is null and ctime is null;
-- A directory entry pointing to a revision.
create table directory_entry_rev
(
id bigserial primary key,
target sha1_git, -- id of target revision
name unix_path, -- path name, relative to containing dir
perms file_perms, -- unix-like permissions
atime timestamptz, -- time of last access
mtime timestamptz, -- time of last modification
ctime timestamptz -- time of last status change
);
create unique index on directory_entry_rev(target, name, perms, atime, mtime, ctime);
create unique index on directory_entry_rev(target, name, perms)
where atime is null and mtime is null and ctime is null;
create table person
(
id bigserial primary key,
name text not null default '',
email text not null default ''
);
create unique index on person(name, email);
create type revision_type as enum ('git', 'tar', 'dsc');
-- A snapshot of a software project at a specific point in time.
--
-- Synonyms/mappings:
-- * git / subversion / etc: commit
-- * tarball: a specific tarball
--
-- Revisions are organized as DAGs. Each revision points to 0, 1, or more (in
-- case of merges) parent revisions. Each revision points to a directory, i.e.,
-- a file-system tree containing files and directories.
create table revision
(
id sha1_git primary key,
date timestamptz,
date_offset smallint,
committer_date timestamptz,
committer_date_offset smallint,
type revision_type not null,
directory sha1_git, -- file-system tree
message bytea,
author bigint references person(id),
committer bigint references person(id)
);
-- either this table or the sha1_git[] column on the revision table
create table revision_history
(
id sha1_git references revision(id),
parent_id sha1_git,
parent_rank int not null default 0,
-- parent position in merge commits, 0-based
primary key (id, parent_rank)
);
-- The content of software origins is indexed starting from top-level pointers
-- called "branches". Every time we fetch some origin we store in this table
-- where the branches pointed to at fetch time.
--
-- Synonyms/mappings:
-- * git: ref (in the "git update-ref" sense)
create table occurrence_history
(
origin bigint references origin(id),
branch text, -- e.g., "master" (for VCS), or "sid" (for Debian)
revision sha1_git, -- ref target, e.g., commit id
authority bigint references organization(id) not null,
-- who is claiming to have seen the occurrence.
-- Note: SWH is such an authority, and has an entry in
-- the organization table.
validity tstzrange, -- The time validity of this table entry. If the upper
-- bound is missing, the entry is still valid.
exclude using gist (origin with =,
branch with =,
revision with =,
authority with =,
validity with &&),
-- unicity exclusion constraint on lines where the same value is found for
-- `origin`, `reference`, `revision`, `authority` and overlapping values for
-- `validity`.
primary key (origin, branch, revision, authority, validity)
);
-- Materialized view of occurrence_history, storing the *current* value of each
-- branch, as last seen by SWH.
create table occurrence
(
origin bigint references origin(id),
branch text,
revision sha1_git,
primary key(origin, branch, revision)
);
-- A "memorable" point in the development history of a project.
--
-- Synonyms/mappings:
-- * git: tag (of the annotated kind, otherwise they are just references)
-- * tarball: the release version number
create table release
(
id sha1_git primary key,
revision sha1_git,
date timestamptz,
date_offset smallint,
name text,
comment bytea,
author bigint references person(id)
);