Dear community,

Apache CouchDB %VERSION% has been released and is available for

CouchDB is a database that completely embraces the web. Store your data
with JSON documents. Access your documents with your web browser, via
HTTP. Query, combine, and transform your documents with JavaScript.
CouchDB works well with modern web and mobile apps. You can distribute
your data, efficiently using CouchDB’s incremental replication. CouchDB
supports master-master setups with automatic conflict detection.

CouchDB comes with a suite of features, such as on-the-fly document
transformation and real-time change notifications, that make web
development a breeze. It even comes with an easy to use web
administration console, served directly out of CouchDB! We care a lot
about distributed scaling. CouchDB is highly available and partition
tolerant, but is also eventually consistent. And we care a lot about
your data. CouchDB has a fault-tolerant storage engine that puts the
safety of your data first.

Download your copy here:

Pre-built convenience binaries for Windows, macOS, Debian/Ubuntu and
RHEL/CentOS are available.

CouchDB 2.1.0 is a feature release, and was originally published on

The community would like to thank all contributors for their part in
making this release, from the smallest bug report or patch to major
contributions in code, design, or marketing, we couldn’t have done it
without you!

The release notes follow. A formatted version of them can be viewed

On behalf of the CouchDB PMC,
Joan Touzet


Version 2.1.0

    The Mango _find endpoint supports a new combination operator, $allMatch, 
which matches and returns all documents that contain an array field with all 
its elements matching all the specified query criteria.

    New scheduling replicator. The core of the new replicator is a scheduler 
which allows running a large number of replication jobs by switching between 
them, stopping some and starting others periodically. Jobs which fail are 
backed off exponentially. There is also an improved inspection and querying 
API: _scheduler/jobs and _scheduler/docs:
        _scheduler/jobs : This endpoint shows active replication jobs. These 
are jobs managed by the scheduler. Some of them might be running, some might be 
waiting to run, or backed off (penalized) because they crashed too many times. 
Semantically this is somewhat equivalent to _active_tasks but focuses only on 
replications. Jobs which have completed or which were never created because of 
malformed replication documents will not be shown here as they are not managed 
by the scheduler. _replicate replications, started form _replicate endpoint not 
from a document in a _replicator db, will also show up here.
        _scheduler/docs : This endpoint is an improvement on having to go back 
and read replication documents to query their state. It represents the state of 
all the replications started from documents in _replicator db. Unlike 
_scheduler/jobs it will also show jobs which have failed or have completed.

    By default, scheduling replicator will not update documents with transient 
states like triggered or error anymore, instead _scheduler/docs API should be 
used to query replication document states.

Other scheduling replicator improvements

        Network resource usage and performance was improved by implementing a 
shared connection pool. This should help in cases of a large number of 
connections to the same sources or target. Previously connection pools were 
shared only withing a single replication job.
        Improved request rate limit handling. Replicator requests will 
auto-discover rate limit capacity on targets and sources based on a proven 
Additive Increase / Multiplicative Decrease feedback control algorithm.
        Improved performance by having exponential backoff for all replication 
jobs failures. Previously there were some scenarios were failure led to 
continuous repeated retries, consuming CPU and disk resources in the process.
        Improved recovery from long but temporary network failure. Currently if 
replications jobs fail to start 10 times in a row, they will not be retried 
anymore. This is sometimes desirable, but in some cases, for example, after a 
sustained DNS failure which eventually recovers, replications reach their retry 
limit, stop retrying and never recover. Previously it required user 
intervention to continue. Scheduling replicator will never give up retrying a 
valid scheduled replication job and so it should recover automatically.
        Better handling of filtered replications. Failing user filter code 
fetches from the source will not block replicator manager and stall other 
replications. Failing filter fetches will also be backed off exponentially. 
Another improvement is when filter code changes on the source, a running 
replication will detect that and restart itself with a new replication ID 

The 2.1.0 release also includes the following minor improvements:

    COUCHDB-1946: Hibernate couch_stream after each write (up to 70% reduction 
in memory usage during replication of DBs with large attachments)
    COUCHDB-2964: Investigate switching replicator manager change feeds to 
using “normal” instead of “longpoll”
    COUCHDB-2988: (mango) Allow query selector as changes and replication filter
    COUCHDB-2992: Add additional support for document size
    COUCHDB-3046: Improve reduce function overflow protection
    COUCHDB-3061: Use vectored reads to search for buried headers in .couch 
files. “On a modern linux system with SSD, we see improvements up to 15x.”
    COUCHDB-3063: “stale=ok” option replaced with new “stable” and “update” 
    COUCHDB-3180: Add features list in the welcome message
    COUCHDB-3203: Make auth handlers configurable (in ini files)
    COUCHDB-3234: Track open shard timeouts with a counter instead of logging
    COUCHDB-3242: Make get view group info timeout in couch_indexer configurable
    COUCHDB-3249: Add config to disable index all fields (text indexes)
    COUCHDB-3251: Remove hot loop usage of filename:rootname/1
    COUCHDB-3284: 8Kb read-ahead in couch_file causes extra IO and binary 
memory usage
    COUCHDB-3298: Optimize writing btree nodes
    COUCHDB-3302: (Improve) Attachment replication over low bandwidth network 
    COUCHDB-3307: Limit calls to maybe_add_sys_db_callbacks to once per db open
    COUCHDB-3318: bypass couch_httpd_vhost if there are none
    COUCHDB-3323: Idle dbs cause excessive overhead
    COUCHDB-3324: Introduce couch_replicator_scheduler
    COUCHDB-3337: End-point _local_docs doesn’t conform to query params of 
    COUCHDB-3358: (mango) Use efficient set storage for field names
    COUCHDB-3425: Make _doc_ids _changes filter fast-path limit configurable
    #457: TeX/LaTeX/texinfo removed from default docs build chain
    #469: (mango) Choose index based on fields match
    #483: couchup database migration tool
    #582: Add X-Frame-Options support to help protect against clickjacking
    #593: Allow bind address of in _cluster_setup for single nodes
    #624: Enable compaction daemon by default
    #626: Allow enable node decom using string “true”
    (mango) Configurable default limit, defaults to 25.
    (mango) _design documents ignored when querying _all_docs
    (mango) add $allMatch selector
    Add local.d/default.d directories by default and document
    Improved INSTALL.* text files

Fixed Issues

The 2.1.0 release includes fixes for the following issues:

    COUCHDB-1447: X-Couch-Update-NewRev header is missed if custom headers are 
specified in response of _update handler (missed in 2.0 merge)
    COUCHDB-2731: Authentication DB was not considered a system DB
    COUCHDB-3010: (Superceded fix for replication exponential backoff)
    COUCHDB-3090: Error when handling empty “Access-Control-Request-Headers” 
    COUCHDB-3100: Fix documentation on require_valid_user
    COUCHDB-3109: 500 when include_docs=true for linked documents
    COUCHDB-3113: fabric:open_revs can return {ok, []}
    COUCHDB-3149: Exception written to the log if db deleted while there is a 
change feed running
    COUCHDB-3150: Update all shards with stale=update_after
    COUCHDB-3158: Fix a crash when connection closes for _update
    COUCHDB-3162: Default ssl settings cause a crash
    COUCHDB-3164: Request fails when using 
    COUCHDB-3168: Replicator doesn’t handle well writing documents to a target 
db which has a small max_document_size
    COUCHDB-3173: Views return corrupt data for text fields containing non-BMP 
    COUCHDB-3174: max_document_size setting can by bypassed by issuing 
multipart/related requests
    COUCHDB-3178: Fabric does not send message when filtering lots of documents
    COUCHDB-3181: function_clause error when adding attachment to doc in _users 
    COUCHDB-3184: couch_mrview_compactor:recompact/1 does not handle errors in 
spawned process
    COUCHDB-3193: fabric:open_revs returns multiple results when one of the 
shards has stem_interactive_updates=false
    COUCHDB-3199: Replicator VDU function doesn’t acount for an already 
malformed document in replicator db
    COUCHDB-3202: (mango) do not allow empty field names
    COUCHDB-3220: Handle timeout in _revs_diff
    COUCHDB-3222: (Fix) HTTP code 500 instead of 400 for invalid key during 
document creation
    COUCHDB-3231: Allow fixing users’ documents (type and roles)
    COUCHDB-3232: user context not passed down in fabric_view_all_docs
    COUCHDB-3238: os_process_limit documentation wrong
    COUCHDB-3241: race condition in couch_server if delete msg for a db is 
received before open_result msg
    COUCHDB-3245: Make couchjs -S option take effect again
    COUCHDB-3252: Include main-coffee.js in release artifact (broken 
CoffeeScript view server)
    COUCHDB-3255: Conflicts introduced by recreating docs with attachments
    COUCHDB-3259: Don’t trap exits in couch_file
    COUCHDB-3264: POST to _all_docs does not respect conflicts=true
    COUCHDB-3269: view response can ‘hang’ with filter and limit specified
    COUCHDB-3271: Replications crash with ‘kaboom’ exit
    COUCHDB-3274: eof in couch_file can be incorrect after error
    COUCHDB-3277: Replication manager crashes when it finds _replicator db 
shards which are not part of a mem3 db
    COUCHDB-3286: Validation function throwing unexpected json crashes with 
    COUCHDB-3289: handle error clause when calling fabric:open_revs
    COUCHDB-3291: Excessively long document IDs prevent replicator from making 
    COUCHDB-3293: Allow limiting length of document ID (for CouchDB proper)
    COUCHDB-3305: (mango) don’t crash with invalid input to built in reducer 
    COUCHDB-3362: DELETE attachment on non-existing document creates the 
document, rather than returning 404
    COUCHDB-3364: Don’t crash compactor when compacting process fails.
    COUCHDB-3367: Require server admin user for db/_compact and db_view_cleanup 
    COUCHDB-3376: Fix mem3_shards under load
    COUCHDB-3378: Fix mango full text detection
    COUCHDB-3379: Fix couch_auth_cache reinitialization logic
    COUCHDB-3400: Notify couch_index_processes on all shards when ddoc updated
    COUCHDB-3402: race condition in mem3 startup
    #511: (mango)  Return false for empty list
    #595: Return 409 to PUT attachment with non-existent rev
    #623: Ensure replicator _active_tasks entry reports recent pending changes 
    #627: Pass UserCtx to fabric’s all_docs from mango query
    #631: fix couchdb_os_proc_pool eunit timeouts
    #644: Make couch_event_sup:stop/1 synchronous
    #645: Pass db open options to fabric_view_map for _view and _list queries 
on _users DB
    #648: Fix couch_replicator_changes_reader:process_change
    #649: Avoid a race when restarting an index updater
    #667: Prevent a terrible race condition
    #677: Make replication filter fetch error for _replicate return a 404
    Fix CORS max_age configuration parameter via Access-Control-Max-Age
    Chunk missing revisions before attempting to save on target (improves 
replication for very conflicted, very deep revision tree documents)
    Allow w parameter for attachments
    Return “Bad Request” when count in /_uuids exceeds max
    Fix crashes when replicator db is deleted
    Skip internal replication if changes already replicated
    Fix encoding issues on _update/../doc_id and PUT attachments

Upgrade Notes

    The deprecated (and broken) OAuth 1.0 implementation has been removed.
    If user code reads or manipulates replicator document states, consider 
using the [replicator] update_docs = true compatibility parameter. In that case 
replicator will continue updating documents with transient replication states. 
However, that will incure a performance cost. Consider instead switching using 
_scheduler/docs HTTP endpoint.
    The stale parameter for views and _find has been deprecated in favour of 
two new parameters: stable and update. The old stale=ok behaviour is equivalent 
to stable=true&update=false, and the old stale=update_after behaviour is 
equivalent to stable=true&update=lazy. The deprecated stale parameter will be 
removed in CouchDB 3.0.
    The [couchdb] max_document_size configuration parameter was renamed to 
[httpd] max_http_request_size to reflect its actual implementation. It has been 
enhanced by a new [couchdb] single_max_doc_size setting. Both are documented in 
the shipped default.ini file.

Reply via email to