1 files changed, 110 insertions, 0 deletions
diff --git a/python/fatcat_tools/mergers/releases.py b/python/fatcat_tools/mergers/releases.py
new file mode 100644
index 00000000..802cb8da
--- /dev/null
+++ b/python/fatcat_tools/mergers/releases.py
@@ -0,0 +1,110 @@
+
+from .common import EntityMerger
+from fatcat_api_client.models import ReleaseEntity, WorkEntity
+
+
+class ReleaseMerger(EntityMerger):
+    """
+    Hard merges a set of release entities, redirecting all entities to a single
+    primary release.
+
+    Will also redirect works (if appropriate), and re-point {files, filesets,
+    webcaptures} to the new merged release.
+    """
+
+    def __init__(self, api, **kwargs):
+
+        eg_desc = kwargs.get('editgroup_description',
+            "Automated merge of release entities")
+        eg_extra = kwargs.get('editgroup_extra', dict())
+        eg_extra['agent'] = eg_extra.get('agent', 'fatcat_tools.ReleaseMerger')
+        super().__init__(api,
+            editgroup_description=eg_desc,
+            editgroup_extra=eg_extra,
+            **kwargs)
+
+    def try_merge(self, idents, primary=None):
+
+        updated_entities = 0
+        releases = dict()
+        eg_id = self.get_editgroup_id()
+
+        self.dry_run_mode
+
+        for ident in idents:
+            releases[ident] = api.get_release(ident, expand="files,filesets,webcaptures")
+
+        # select the primary (if not already set)
+        if not primary:
+            primary = releases.keys()[0]
+
+        primary_work_id = releases[primary].work_id
+        updated_work_ids = []
+        redirected_release_ids = []
+
+        # execute all the release redirects
+        for release in releases.values():
+            if release.ident == primary:
+                continue
+
+            # file redirects
+            for e in release.files:
+                e.release_ids.remove(release.ident)
+                if not primary in e.release_ids:
+                    e.release_ids.append(primary)
+                if not self.dry_run_mode:
+                    api.update_file(eg_id, e.ident, e)
+                updated_entities += 1
+                self.counts['updated-files'] += 1
+
+            # fileset redirects
+            for e in release.filesets:
+                e.release_ids.remove(release.ident)
+                if not primary in e.release_ids:
+                    e.release_ids.append(primary)
+                if not self.dry_run_mode:
+                    api.update_fileset(eg_id, e.ident, e)
+                updated_entities += 1
+                self.counts['updated-filesets'] += 1
+
+            # webcapture redirects
+            for e in release.webcaptures:
+                e.release_ids.remove(release.ident)
+                if not primary in e.release_ids:
+                    e.release_ids.append(primary)
+                if not self.dry_run_mode:
+                    api.update_webcapture(eg_id, e.ident, e)
+                updated_entities += 1
+                self.counts['updated-webcaptures'] += 1
+
+            # release redirect itself
+            updated_work_ids.append(release.work_id)
+            redirected_release_ids.append(release.ident)
+            if not self.dry_run_mode:
+                api.update_release(eg_id, release.ident, ReleaseEntity(redirect=primary))
+            updated_entities += 1
+            self.counts['updated-releases']
+
+
+        # lastly, clean up any merged work entities
+        redirected_release_ids = set(redirected_release_ids)
+        updated_work_ids = list(set(updated_work_ids))
+        assert primary_work_id not in updated_work_ids
+        for work_id in updated_work_ids:
+            work_releases = api.get_work_releases(work_id)
+            rids = set([r.ident for r in work_releases])
+            if rids.issubset(redirected_release_ids):
+                # all the releases for this work were updated/merged; we should
+                # redirect to primary work_id
+                # also check we don't have any in-flight edit conflicts
+                assert not work_id in self._idents_inflight
+                self._idents_inflight.append(work_id)
+                if not self.dry_run_mode:
+                    api.update_work(eg_id, work_id, WorkEntity(redirect=primary_work_id))
+                updated_entities += 1
+                self.counts['updated-works'] += 1
+
+        return updated_entities
+
+class ReleaseGrouper(EntityMerger):
+    pass