public RevisionList ChangesSince(Int64 lastSequence, ChangesOptions options, RevisionFilter filter)
{
// http://wiki.apache.org/couchdb/HTTP_database_API#Changes
// Translate options to ForestDB:
if (options.Descending) {
// https://github.com/couchbase/couchbase-lite-ios/issues/641
throw new CouchbaseLiteException(StatusCode.NotImplemented);
}
var forestOps = C4EnumeratorOptions.DEFAULT;
forestOps.flags |= C4EnumeratorFlags.IncludeDeleted | C4EnumeratorFlags.IncludeNonConflicted;
if (options.IncludeDocs || options.IncludeConflicts || filter != null) {
forestOps.flags |= C4EnumeratorFlags.IncludeBodies;
}
var changes = new RevisionList();
var e = new CBForestDocEnumerator(Forest, lastSequence, forestOps);
foreach (var next in e) {
var doc = next.Document;
var revs = default(IEnumerable<RevisionInternal>);
if (options.IncludeConflicts) {
using (var enumerator = new CBForestHistoryEnumerator(doc, true, false)) {
var includeBody = forestOps.flags.HasFlag(C4EnumeratorFlags.IncludeBodies);
revs = enumerator.Select(x => new RevisionInternal(x.Document, includeBody)).ToList();
}
} else {
revs = new List<RevisionInternal> { new RevisionInternal(doc, forestOps.flags.HasFlag(C4EnumeratorFlags.IncludeBodies)) };
}
foreach (var rev in revs) {
Debug.Assert(rev != null);
if (filter == null || filter(rev)) {
if (!options.IncludeDocs) {
rev.SetBody(null);
}
if(filter == null || filter(rev)) {
changes.Add(rev);
}
}
}
}
if (options.SortBySequence) {
changes.SortBySequence(!options.Descending);
changes.Limit(options.Limit);
}
return changes;
}
/// <summary>
/// Returns a sorted list of changes made to documents in the database, in time order of application.
/// </summary>
/// <returns>The response state for further HTTP processing</returns>
/// <param name="context">The context of the Couchbase Lite HTTP request</param>
/// <remarks>
/// http://docs.couchdb.org/en/latest/api/database/changes.html#get--db-_changes
/// <remarks>
public static ICouchbaseResponseState GetChanges(ICouchbaseListenerContext context)
{
DBMonitorCouchbaseResponseState responseState = new DBMonitorCouchbaseResponseState();
var responseObject = PerformLogicWithDatabase(context, true, db =>
{
var response = context.CreateResponse();
responseState.Response = response;
if (context.ChangesFeedMode < ChangesFeedMode.Continuous) {
if(context.CacheWithEtag(db.LastSequenceNumber.ToString())) {
response.InternalStatus = StatusCode.NotModified;
return response;
}
}
var options = new ChangesOptions();
responseState.Db = db;
responseState.ContentOptions = context.ContentOptions;
responseState.ChangesFeedMode = context.ChangesFeedMode;
responseState.ChangesIncludeDocs = context.GetQueryParam<bool>("include_docs", bool.TryParse, false);
options.SetIncludeDocs(responseState.ChangesIncludeDocs);
responseState.ChangesIncludeConflicts = context.GetQueryParam("style") == "all_docs";
options.SetIncludeConflicts(responseState.ChangesIncludeConflicts);
options.SetContentOptions(context.ContentOptions);
options.SetSortBySequence(!options.IsIncludeConflicts());
options.SetLimit(context.GetQueryParam<int>("limit", int.TryParse, options.GetLimit()));
int since = context.GetQueryParam<int>("since", int.TryParse, 0);
string filterName = context.GetQueryParam("filter");
if(filterName != null) {
Status status = new Status();
responseState.ChangesFilter = db.GetFilter(filterName, status);
if(responseState.ChangesFilter == null) {
return context.CreateResponse(status.Code);
}
responseState.FilterParams = context.GetQueryParams();
}
RevisionList changes = db.ChangesSince(since, options, responseState.ChangesFilter, responseState.FilterParams);
if((context.ChangesFeedMode >= ChangesFeedMode.Continuous) ||
(context.ChangesFeedMode == ChangesFeedMode.LongPoll && changes.Count == 0)) {
// Response is going to stay open (continuous, or hanging GET):
response.Chunked = true;
if(context.ChangesFeedMode == ChangesFeedMode.EventSource) {
response["Content-Type"] = "text/event-stream; charset=utf-8";
}
if(context.ChangesFeedMode >= ChangesFeedMode.Continuous) {
response.WriteHeaders();
foreach(var rev in changes) {
response.SendContinuousLine(ChangesDictForRev(rev, responseState), context.ChangesFeedMode);
}
}
responseState.SubscribeToDatabase(db);
string heartbeatParam = context.GetQueryParam("heartbeat");
if(heartbeatParam != null) {
int heartbeat;
if(!int.TryParse(heartbeatParam, out heartbeat) || heartbeat <= 0) {
responseState.IsAsync = false;
return context.CreateResponse(StatusCode.BadParam);
}
heartbeat = Math.Min(heartbeat, MIN_HEARTBEAT);
string heartbeatResponse = context.ChangesFeedMode == ChangesFeedMode.EventSource ? "\n\n" : "\r\n";
responseState.StartHeartbeat(heartbeatResponse, heartbeat);
}
return context.CreateResponse();
} else {
if(responseState.ChangesIncludeConflicts) {
response.JsonBody = new Body(ResponseBodyForChanges(changes, since, options.GetLimit(), responseState));
} else {
response.JsonBody = new Body(ResponseBodyForChanges(changes, since, responseState));
}
return response;
}
});
responseState.Response = responseObject;
return responseState;
}
