path: root/git-interface/git-update.py

#!/usr/bin/python3

import os
import pygit2
import re
import subprocess
import sys
import time

import srcinfo.parse
import srcinfo.utils

import config
import db

notify_cmd = config.get('notifications', 'notify-cmd')

repo_path = config.get('serve', 'repo-path')
repo_regex = config.get('serve', 'repo-regex')

max_blob_size = config.getint('update', 'max-blob-size')


def size_humanize(num):
    for unit in ['B', 'KiB', 'MiB', 'GiB', 'TiB', 'PiB', 'EiB', 'ZiB']:
        if abs(num) < 2048.0:
            if isinstance(num, int):
                return "{}{}".format(num, unit)
            else:
                return "{:.2f}{}".format(num, unit)
        num /= 1024.0
    return "{:.2f}{}".format(num, 'YiB')


def extract_arch_fields(pkginfo, field):
    values = []

    if field in pkginfo:
        for val in pkginfo[field]:
            values.append({"value": val, "arch": None})

    for arch in ['i686', 'x86_64']:
        if field + '_' + arch in pkginfo:
            for val in pkginfo[field + '_' + arch]:
                values.append({"value": val, "arch": arch})

    return values


def parse_dep(depstring):
    dep, _, desc = depstring.partition(': ')
    depname = re.sub(r'(<|=|>).*', '', dep)
    depcond = dep[len(depname):]

    if (desc):
        return (depname + ': ' + desc, depcond)
    else:
        return (depname, depcond)


def save_metadata(metadata, conn, user):
    # Obtain package base ID and previous maintainer.
    pkgbase = metadata['pkgbase']
    cur = conn.execute("SELECT ID, MaintainerUID FROM PackageBases "
                       "WHERE Name = ?", [pkgbase])
    (pkgbase_id, maintainer_uid) = cur.fetchone()
    was_orphan = not maintainer_uid

    # Obtain the user ID of the new maintainer.
    cur = conn.execute("SELECT ID FROM Users WHERE Username = ?", [user])
    user_id = int(cur.fetchone()[0])

    # Update package base details and delete current packages.
    now = int(time.time())
    conn.execute("UPDATE PackageBases SET ModifiedTS = ?, " +
                 "PackagerUID = ?, OutOfDateTS = NULL WHERE ID = ?",
                 [now, user_id, pkgbase_id])
    conn.execute("UPDATE PackageBases SET MaintainerUID = ? " +
                 "WHERE ID = ? AND MaintainerUID IS NULL",
                 [user_id, pkgbase_id])
    conn.execute("DELETE FROM Packages WHERE PackageBaseID = ?",
                 [pkgbase_id])

    for pkgname in srcinfo.utils.get_package_names(metadata):
        pkginfo = srcinfo.utils.get_merged_package(pkgname, metadata)

        if 'epoch' in pkginfo and int(pkginfo['epoch']) > 0:
            ver = '{:d}:{:s}-{:s}'.format(int(pkginfo['epoch']),
                                          pkginfo['pkgver'],
                                          pkginfo['pkgrel'])
        else:
            ver = '{:s}-{:s}'.format(pkginfo['pkgver'], pkginfo['pkgrel'])

        for field in ('pkgdesc', 'url'):
            if field not in pkginfo:
                pkginfo[field] = None

        # Create a new package.
        cur = conn.execute("INSERT INTO Packages (PackageBaseID, Name, " +
                           "Version, Description, URL) " +
                           "VALUES (?, ?, ?, ?, ?)",
                           [pkgbase_id, pkginfo['pkgname'], ver,
                            pkginfo['pkgdesc'], pkginfo['url']])
        conn.commit()
        pkgid = cur.lastrowid

        # Add package sources.
        for source_info in extract_arch_fields(pkginfo, 'source'):
            conn.execute("INSERT INTO PackageSources (PackageID, Source, " +
                         "SourceArch) VALUES (?, ?, ?)",
                         [pkgid, source_info['value'], source_info['arch']])

        # Add package dependencies.
        for deptype in ('depends', 'makedepends',
                        'checkdepends', 'optdepends'):
            cur = conn.execute("SELECT ID FROM DependencyTypes WHERE Name = ?",
                               [deptype])
            deptypeid = cur.fetchone()[0]
            for dep_info in extract_arch_fields(pkginfo, deptype):
                depname, depcond = parse_dep(dep_info['value'])
                deparch = dep_info['arch']
                conn.execute("INSERT INTO PackageDepends (PackageID, " +
                             "DepTypeID, DepName, DepCondition, DepArch) " +
                             "VALUES (?, ?, ?, ?, ?)",
                             [pkgid, deptypeid, depname, depcond, deparch])

        # Add package relations (conflicts, provides, replaces).
        for reltype in ('conflicts', 'provides', 'replaces'):
            cur = conn.execute("SELECT ID FROM RelationTypes WHERE Name = ?",
                               [reltype])
            reltypeid = cur.fetchone()[0]
            for rel_info in extract_arch_fields(pkginfo, reltype):
                relname, relcond = parse_dep(rel_info['value'])
                relarch = rel_info['arch']
                conn.execute("INSERT INTO PackageRelations (PackageID, " +
                             "RelTypeID, RelName, RelCondition, RelArch) " +
                             "VALUES (?, ?, ?, ?, ?)",
                             [pkgid, reltypeid, relname, relcond, relarch])

        # Add package licenses.
        if 'license' in pkginfo:
            for license in pkginfo['license']:
                cur = conn.execute("SELECT ID FROM Licenses WHERE Name = ?",
                                   [license])
                row = cur.fetchone()
                if row:
                    licenseid = row[0]
                else:
                    cur = conn.execute("INSERT INTO Licenses (Name) " +
                                       "VALUES (?)", [license])
                    conn.commit()
                    licenseid = cur.lastrowid
                conn.execute("INSERT INTO PackageLicenses (PackageID, " +
                             "LicenseID) VALUES (?, ?)",
                             [pkgid, licenseid])

        # Add package groups.
        if 'groups' in pkginfo:
            for group in pkginfo['groups']:
                cur = conn.execute("SELECT ID FROM Groups WHERE Name = ?",
                                   [group])
                row = cur.fetchone()
                if row:
                    groupid = row[0]
                else:
                    cur = conn.execute("INSERT INTO Groups (Name) VALUES (?)",
                                       [group])
                    conn.commit()
                    groupid = cur.lastrowid
                conn.execute("INSERT INTO PackageGroups (PackageID, "
                             "GroupID) VALUES (?, ?)", [pkgid, groupid])

    # Add user to notification list on adoption.
    if was_orphan:
        cur = conn.execute("SELECT COUNT(*) FROM PackageNotifications WHERE " +
                           "PackageBaseID = ? AND UserID = ?",
                           [pkgbase_id, user_id])
        if cur.fetchone()[0] == 0:
            conn.execute("INSERT INTO PackageNotifications " +
                         "(PackageBaseID, UserID) VALUES (?, ?)",
                         [pkgbase_id, user_id])

    conn.commit()


def update_notify(conn, user, pkgbase_id):
    # Obtain the user ID of the new maintainer.
    cur = conn.execute("SELECT ID FROM Users WHERE Username = ?", [user])
    user_id = int(cur.fetchone()[0])

    # Execute the notification script.
    subprocess.Popen((notify_cmd, 'update', str(user_id), str(pkgbase_id)))


def die(msg):
    sys.stderr.write("error: {:s}\n".format(msg))
    exit(1)


def warn(msg):
    sys.stderr.write("warning: {:s}\n".format(msg))


def die_commit(msg, commit):
    sys.stderr.write("error: The following error " +
                     "occurred when parsing commit\n")
    sys.stderr.write("error: {:s}:\n".format(commit))
    sys.stderr.write("error: {:s}\n".format(msg))
    exit(1)


repo = pygit2.Repository(repo_path)

user = os.environ.get("AUR_USER")
pkgbase = os.environ.get("AUR_PKGBASE")
privileged = (os.environ.get("AUR_PRIVILEGED", '0') == '1')
warn_or_die = warn if privileged else die

if len(sys.argv) == 2 and sys.argv[1] == "restore":
    if 'refs/heads/' + pkgbase not in repo.listall_references():
        die('{:s}: repository not found: {:s}'.format(sys.argv[1], pkgbase))
    refname = "refs/heads/master"
    sha1_old = sha1_new = repo.lookup_reference('refs/heads/' + pkgbase).target
elif len(sys.argv) == 4:
    refname, sha1_old, sha1_new = sys.argv[1:4]
else:
    die("invalid arguments")

if refname != "refs/heads/master":
    die("pushing to a branch other than master is restricted")

conn = db.Connection()

# Detect and deny non-fast-forwards.
if sha1_old != "0000000000000000000000000000000000000000" and not privileged:
    walker = repo.walk(sha1_old, pygit2.GIT_SORT_TOPOLOGICAL)
    walker.hide(sha1_new)
    if next(walker, None) is not None:
        die("denying non-fast-forward (you should pull first)")

# Prepare the walker that validates new commits.
walker = repo.walk(sha1_new, pygit2.GIT_SORT_TOPOLOGICAL)
if sha1_old != "0000000000000000000000000000000000000000":
    walker.hide(sha1_old)

# Validate all new commits.
for commit in walker:
    for fname in ('.SRCINFO', 'PKGBUILD'):
        if fname not in commit.tree:
            die_commit("missing {:s}".format(fname), str(commit.id))

    for treeobj in commit.tree:
        blob = repo[treeobj.id]

        if isinstance(blob, pygit2.Tree):
            die_commit("the repository must not contain subdirectories",
                       str(commit.id))

        if not isinstance(blob, pygit2.Blob):
            die_commit("not a blob object: {:s}".format(treeobj),
                       str(commit.id))

        if blob.size > max_blob_size:
            die_commit("maximum blob size ({:s}) exceeded".format(size_humanize(max_blob_size)), str(commit.id))

    metadata_raw = repo[commit.tree['.SRCINFO'].id].data.decode()
    (metadata, errors) = srcinfo.parse.parse_srcinfo(metadata_raw)
    if errors:
        sys.stderr.write("error: The following errors occurred "
                         "when parsing .SRCINFO in commit\n")
        sys.stderr.write("error: {:s}:\n".format(str(commit.id)))
        for error in errors:
            for err in error['error']:
                sys.stderr.write("error: line {:d}: {:s}\n".format(error['line'], err))
        exit(1)

    metadata_pkgbase = metadata['pkgbase']
    if not re.match(repo_regex, metadata_pkgbase):
        die_commit('invalid pkgbase: {:s}'.format(metadata_pkgbase),
                   str(commit.id))

    for pkgname in set(metadata['packages'].keys()):
        pkginfo = srcinfo.utils.get_merged_package(pkgname, metadata)

        for field in ('pkgver', 'pkgrel', 'pkgname'):
            if field not in pkginfo:
                die_commit('missing mandatory field: {:s}'.format(field),
                           str(commit.id))

        if 'epoch' in pkginfo and not pkginfo['epoch'].isdigit():
            die_commit('invalid epoch: {:s}'.format(pkginfo['epoch']),
                       str(commit.id))

        if not re.match(r'[a-z0-9][a-z0-9\.+_-]*$', pkginfo['pkgname']):
            die_commit('invalid package name: {:s}'.format(pkginfo['pkgname']),
                       str(commit.id))

        for field in ('pkgname', 'pkgdesc', 'url'):
            if field in pkginfo and len(pkginfo[field]) > 255:
                die_commit('{:s} field too long: {:s}'.format(field, pkginfo[field]),
                           str(commit.id))

        for field in ('install', 'changelog'):
            if field in pkginfo and not pkginfo[field] in commit.tree:
                die_commit('missing {:s} file: {:s}'.format(field, pkginfo[field]),
                           str(commit.id))

        for field in extract_arch_fields(pkginfo, 'source'):
            fname = field['value']
            if "://" in fname or "lp:" in fname:
                continue
            if fname not in commit.tree:
                die_commit('missing source file: {:s}'.format(fname),
                           str(commit.id))


# Display a warning if .SRCINFO is unchanged.
if sha1_old not in ("0000000000000000000000000000000000000000", sha1_new):
    srcinfo_id_old = repo[sha1_old].tree['.SRCINFO'].id
    srcinfo_id_new = repo[sha1_new].tree['.SRCINFO'].id
    if srcinfo_id_old == srcinfo_id_new:
        warn(".SRCINFO unchanged. The package database will not be updated!")

# Read .SRCINFO from the HEAD commit.
metadata_raw = repo[repo[sha1_new].tree['.SRCINFO'].id].data.decode()
(metadata, errors) = srcinfo.parse.parse_srcinfo(metadata_raw)

# Ensure that the package base name matches the repository name.
metadata_pkgbase = metadata['pkgbase']
if metadata_pkgbase != pkgbase:
    die('invalid pkgbase: {:s}, expected {:s}'.format(metadata_pkgbase, pkgbase))

# Ensure that packages are neither blacklisted nor overwritten.
pkgbase = metadata['pkgbase']
cur = conn.execute("SELECT ID FROM PackageBases WHERE Name = ?", [pkgbase])
row = cur.fetchone()
pkgbase_id = row[0] if row else 0

cur = conn.execute("SELECT Name FROM PackageBlacklist")
blacklist = [row[0] for row in cur.fetchall()]

cur = conn.execute("SELECT Name, Repo FROM OfficialProviders")
providers = dict(cur.fetchall())

for pkgname in srcinfo.utils.get_package_names(metadata):
    pkginfo = srcinfo.utils.get_merged_package(pkgname, metadata)
    pkgname = pkginfo['pkgname']

    if pkgname in blacklist:
        warn_or_die('package is blacklisted: {:s}'.format(pkgname))
    if pkgname in providers:
        repo = providers[pkgname]
        warn_or_die('package already provided by [{:s}]: {:s}'.format(repo, pkgname))

    cur = conn.execute("SELECT COUNT(*) FROM Packages WHERE Name = ? AND " +
                       "PackageBaseID <> ?", [pkgname, pkgbase_id])
    if cur.fetchone()[0] > 0:
        die('cannot overwrite package: {:s}'.format(pkgname))

# Store package base details in the database.
save_metadata(metadata, conn, user)

# Create (or update) a branch with the name of the package base for better
# accessibility.
repo.create_reference('refs/heads/' + pkgbase, sha1_new, True)

# Work around a Git bug: The HEAD ref is not updated when using gitnamespaces.
# This can be removed once the bug fix is included in Git mainline. See
# http://git.661346.n2.nabble.com/PATCH-receive-pack-Create-a-HEAD-ref-for-ref-namespace-td7632149.html
# for details.
repo.create_reference('refs/namespaces/' + pkgbase + '/HEAD', sha1_new, True)

# Send package update notifications.
update_notify(conn, user, pkgbase_id)

# Close the database.
conn.close()