Merge pull request #2329 from timrchavez/rebuild-pad-script

Restore pad to new location at a given revision

bin/rebuildPad.js

@@ -0,0 +1,120 @@
+/*
+  This is a repair tool. It rebuilds an old pad at a new pad location up to a
+  known "good" revision.
+*/
+
+if(process.argv.length != 4 && process.argv.length != 5) {
+  console.error("Use: node bin/repairPad.js $PADID $REV [$NEWPADID]");
+  process.exit(1);
+}
+
+var npm = require("../src/node_modules/npm");
+var async = require("../src/node_modules/async");
+var ueberDB = require("../src/node_modules/ueberDB");
+
+var padId = process.argv[2];
+var newRevHead = process.argv[3];
+var newPadId = process.argv[4] || padId + "-rebuilt";
+
+var db, oldPad, newPad, settings;
+var AuthorManager, ChangeSet, Pad, PadManager;
+
+async.series([
+  function(callback) {
+    npm.load({}, function(err) {
+      if(err) {
+        console.error("Could not load NPM: " + err)
+        process.exit(1);
+      } else {
+        callback();
+      }
+    })
+  },
+  function(callback) {
+    // Get a handle into the database
+    db = require('../src/node/db/DB');
+    db.init(callback);
+  }, function(callback) {
+     PadManager = require('../src/node/db/PadManager');
+     Pad = require('../src/node/db/Pad').Pad;
+     // Get references to the original pad and to a newly created pad
+     // HACK: This is a standalone script, so we want to write everything
+     // out to the database immediately.  The only problem with this is
+     // that a driver (like the mysql driver) can hardcode these values.
+     db.db.db.settings = {cache: 0, writeInterval: 0, json: true};
+     // Validate the newPadId if specified and that a pad with that ID does
+     // not already exist to avoid overwriting it.
+     if (!PadManager.isValidPadId(newPadId)) {
+       console.error("Cannot create a pad with that id as it is invalid");
+       process.exit(1);
+     }
+     PadManager.doesPadExists(newPadId, function(err, exists) {
+       if (exists) {
+         console.error("Cannot create a pad with that id as it already exists");
+         process.exit(1);
+       }
+     });
+     PadManager.getPad(padId, function(err, pad)  {
+       oldPad = pad;
+       newPad = new Pad(newPadId);
+       callback();
+     });
+  }, function(callback) {
+    // Clone all Chat revisions
+    var chatHead = oldPad.chatHead;
+    for(var i = 0, curHeadNum = 0; i <= chatHead; i++) {
+      db.db.get("pad:" + padId + ":chat:" + i, function (err, chat) {
+        db.db.set("pad:" + newPadId + ":chat:" + curHeadNum++, chat);
+        console.log("Created: Chat Revision: pad:" + newPadId + ":chat:" + curHeadNum);
+      });
+    }
+    callback();
+  }, function(callback) {
+    // Rebuild Pad from revisions up to and including the new revision head
+    AuthorManager = require("../src/node/db/AuthorManager");
+    Changeset = require("ep_etherpad-lite/static/js/Changeset");
+    // Author attributes are derived from changesets, but there can also be
+    // non-author attributes with specific mappings that changesets depend on
+    // and, AFAICT, cannot be recreated any other way
+    newPad.pool.numToAttrib = oldPad.pool.numToAttrib;
+    for(var curRevNum = 0; curRevNum <= newRevHead; curRevNum++) {
+      db.db.get("pad:" + padId + ":revs:" + curRevNum, function(err, rev) {
+        var newRevNum = ++newPad.head;
+        var newRevId = "pad:" + newPad.id + ":revs:" + newRevNum;
+        db.db.set(newRevId, rev);
+        AuthorManager.addPad(rev.meta.author, newPad.id);
+        newPad.atext = Changeset.applyToAText(rev.changeset, newPad.atext, newPad.pool);
+        console.log("Created: Revision: pad:" + newPad.id + ":revs:" + newRevNum);
+        if (newRevNum == newRevHead) {
+          callback();
+        }
+      });
+    }
+  }, function(callback) {
+    // Add saved revisions up to the new revision head
+    console.log(newPad.head);
+    var newSavedRevisions = [];
+    for(var i in oldPad.savedRevisions) {
+      savedRev = oldPad.savedRevisions[i]
+      if (savedRev.revNum <= newRevHead) {
+        newSavedRevisions.push(savedRev);
+        console.log("Added: Saved Revision: " + savedRev.revNum);
+      }
+    }
+    newPad.savedRevisions = newSavedRevisions;
+    callback();
+  }, function(callback) {
+    // Save the source pad
+    db.db.set("pad:"+newPadId, newPad, function(err) {
+      console.log("Created: Source Pad: pad:" + newPadId);
+      newPad.saveToDatabase();
+      callback();
+    });
+  }
+], function (err) {
+  if(err) throw err;
+  else {
+    console.info("finished");
+    process.exit(0);
+  }
+});