Cannot modify header information (Sapi.php:132) NC 19.0.2

[altosch]

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Steps to reproduce

Upgrade to NC 19.0.2.

Expected behaviour

No PHP errors in the log.

Actual behaviour

Since upgrade to 19.0.2 many error messages like this in the log:

[PHP] Error: Cannot modify header information - headers already sent by 
(output started at /var/www/nextcloud/3rdparty/sabre/http/lib/Sapi.php:132) 
at /var/www/nextcloud/apps/dav/lib/Connector/Sabre/File.php#680

PUT /remote.php/dav/uploads/john/4291849725/00000002
from 111.222.333.444 by john at 2020-08-29T19:34:41+02:00

{"reqId":"Or0R2pucFGt5YGzIyZcI","level":3,"time":"2020-08-29T19:34:41+02:00","remoteAddr":"111.222.333.444",
"user":"john","app":"PHP","method":"PUT","url":"/remote.php/dav/uploads/john/4291849725/00000002",
"message":"Cannot modify header information - headers already sent by 
(output started at /var/www/nextcloud/3rdparty/sabre/http/lib/Sapi.php:132)
 at /var/www/nextcloud/apps/dav/lib/Connector/Sabre/File.php#680",
"userAgent":"Mozilla/5.0 (Windows) mirall/2.6.5stable-Win64 (build 20200710) (Nextcloud)","version":"19.0.2.2","id":"5f4c9578c0b93"}

Server configuration

Operating system:
Ubuntu 18.04.5 LTS
Web server:
nginx version: nginx/1.19.2
Database:
MariaDB 10.1.44
PHP version:
7.2.33 (PHP 7.2.33-1+ubuntu18.04.1+deb.sury.org+1)
Nextcloud version:
19.0.2
Updated from an older Nextcloud/ownCloud or fresh install:
Updated from 18.0.8
Where did you install Nextcloud from:
Web admin update
Signing status:

Signing status

No errors have been found.

List of activated apps:

App list

Enabled:
  - accessibility: 1.5.0
  - activity: 2.12.0
  - admin_audit: 1.9.0
  - calendar: 2.0.4
  - cloud_federation_api: 1.2.0
  - comments: 1.9.0
  - contacts: 3.3.0
  - contactsinteraction: 1.0.0
  - dav: 1.15.0
  - federatedfilesharing: 1.9.0
  - files: 1.14.0
  - files_pdfviewer: 1.8.0
  - files_rightclick: 0.16.0
  - files_sharing: 1.11.0
  - files_trashbin: 1.9.0
  - files_versions: 1.12.0
  - files_videoplayer: 1.8.0
  - logreader: 2.4.0
  - lookup_server_connector: 1.7.0
  - nextcloud_announcements: 1.8.0
  - notes: 3.6.4
  - notifications: 2.7.0
  - oauth2: 1.7.0
  - password_policy: 1.9.1
  - photos: 1.1.0
  - privacy: 1.3.0
  - provisioning_api: 1.9.0
  - recommendations: 0.7.0
  - richdocuments: 3.7.3
  - serverinfo: 1.9.0
  - settings: 1.1.0
  - sharebymail: 1.9.0
  - spreed: 9.0.3
  - support: 1.2.1
  - tasks: 0.13.3
  - text: 3.0.1
  - theming: 1.10.0
  - twofactor_backupcodes: 1.8.0
  - updatenotification: 1.9.0
  - viewer: 1.3.0
  - workflowengine: 2.1.0
Disabled:
  - encryption
  - federation
  - files_external
  - firstrunwizard
  - survey_client
  - systemtags
  - user_ldap

Nextcloud configuration:

Config report

{
    "system": {
        "instanceid": "***REMOVED SENSITIVE VALUE***",
        "passwordsalt": "***REMOVED SENSITIVE VALUE***",
        "secret": "***REMOVED SENSITIVE VALUE***",
        "trusted_domains": [
            "localhost",
            "cloud.mydomain.com"
        ],
        "datadirectory": "***REMOVED SENSITIVE VALUE***",
        "overwrite.cli.url": "https:\/\/cloud.mydomain.com",
        "dbtype": "mysql",
        "version": "19.0.2.2",
        "dbname": "***REMOVED SENSITIVE VALUE***",
        "dbhost": "***REMOVED SENSITIVE VALUE***",
        "dbport": "",
        "dbtableprefix": "oc_",
        "mysql.utf8mb4": true,
        "dbuser": "***REMOVED SENSITIVE VALUE***",
        "dbpassword": "***REMOVED SENSITIVE VALUE***",
        "installed": true,
        "activity_expire_days": 14,
        "auth.bruteforce.protection.enabled": true,
        "blacklisted_files": [
            ".htaccess",
            "Thumbs.db",
            "thumbs.db"
        ],
        "cron_log": true,
        "enable_previews": true,
        "enabledPreviewProviders": [
            "OC\\Preview\\PNG",
            "OC\\Preview\\JPEG",
            "OC\\Preview\\GIF",
            "OC\\Preview\\BMP",
            "OC\\Preview\\XBitmap",
            "OC\\Preview\\Movie",
            "OC\\Preview\\PDF",
            "OC\\Preview\\MP3",
            "OC\\Preview\\TXT",
            "OC\\Preview\\MarkDown"
        ],
        "filesystem_check_changes": 0,
        "filelocking.enabled": "true",
        "htaccess.RewriteBase": "\/",
        "integrity.check.disabled": false,
        "knowledgebaseenabled": false,
        "logfile": "\/var\/nc_data\/nextcloud.log",
        "loglevel": 2,
        "logtimezone": "Europe\/Prague",
        "log_rotate_size": 104857600,
        "maintenance": false,
        "memcache.local": "\\OC\\Memcache\\APCu",
        "memcache.locking": "\\OC\\Memcache\\Redis",
        "overwriteprotocol": "https",
        "preview_max_x": 1024,
        "preview_max_y": 768,
        "preview_max_scale_factor": 1,
        "redis": {
            "host": "***REMOVED SENSITIVE VALUE***",
            "port": 0,
            "timeout": 0
        },
        "quota_include_external_storage": false,
        "share_folder": "\/Shares",
        "skeletondirectory": "",
        "theme": "",
        "trashbin_retention_obligation": "auto, 7",
        "updater.release.channel": "stable",
        "mail_smtpmode": "smtp",
        "mail_smtpauthtype": "LOGIN",
        "mail_smtpsecure": "tls",
        "mail_from_address": "***REMOVED SENSITIVE VALUE***",
        "mail_domain": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpauth": 1,
        "mail_smtphost": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpport": "587",
        "mail_smtpname": "***REMOVED SENSITIVE VALUE***",
        "mail_smtppassword": "***REMOVED SENSITIVE VALUE***",
        "mail_smtptimeout": 45,
        "force_language": "cs",
        "lost_password_link": "disabled",
        "mail_sendmailmode": "smtp"
    }
}

Are you using external storage, if yes which one: no

Are you using encryption: no

Are you using an external user-backend, if yes which one: no

Client configuration

Browser:

Operating system:

Logs

Web server error log

Web server error log

Insert your webserver log here

Nextcloud log (data/nextcloud.log)

Nextcloud log

Similar messages repeated many times:

{"reqId":"xTDKPVJiXelxcS5xfQ2F","level":3,"time":"2020-08-28T16:03:27+02:00","remoteAddr":"555.666.777.888","user":"john","app":"no app in context","method":"PUT","url":"/remote.php/webdav/WORK/myfile.txt","message":{"Exception":"Sabre\\DAV\\Exception\\BadRequest","Message":"Expected filesize of 1303 bytes but read (from Nextcloud client) and wrote (to Nextcloud storage) 0 bytes. Could either be a network problem on the sending side or a problem writing to the storage on the server side.","Code":0,"Trace":[{"file":"/var/www/nextcloud/apps/dav/lib/Connector/Sabre/Directory.php","line":154,"function":"put","class":"OCA\\DAV\\Connector\\Sabre\\File","type":"->","args":[null]},{"file":"/var/www/nextcloud/3rdparty/sabre/dav/lib/DAV/Server.php","line":1104,"function":"createFile","class":"OCA\\DAV\\Connector\\Sabre\\Directory","type":"->","args":["myfile.txt",null]},{"file":"/var/www/nextcloud/3rdparty/sabre/dav/lib/DAV/CorePlugin.php","line":527,"function":"createFile","class":"Sabre\\DAV\\Server","type":"->","args":["WORK/myfile.txt",null,null]},{"file":"/var/www/nextcloud/3rdparty/sabre/event/lib/WildcardEmitterTrait.php","line":89,"function":"httpPut","class":"Sabre\\DAV\\CorePlugin","type":"->","args":[{"__class__":"Sabre\\HTTP\\Request"},{"__class__":"Sabre\\HTTP\\Response"}]},{"file":"/var/www/nextcloud/3rdparty/sabre/dav/lib/DAV/Server.php","line":474,"function":"emit","class":"Sabre\\DAV\\Server","type":"->","args":["method:PUT",[{"__class__":"Sabre\\HTTP\\Request"},{"__class__":"Sabre\\HTTP\\Response"}]]},{"file":"/var/www/nextcloud/3rdparty/sabre/dav/lib/DAV/Server.php","line":251,"function":"invokeMethod","class":"Sabre\\DAV\\Server","type":"->","args":[{"__class__":"Sabre\\HTTP\\Request"},{"__class__":"Sabre\\HTTP\\Response"}]},{"file":"/var/www/nextcloud/3rdparty/sabre/dav/lib/DAV/Server.php","line":319,"function":"start","class":"Sabre\\DAV\\Server","type":"->","args":[]},{"file":"/var/www/nextcloud/apps/dav/appinfo/v1/webdav.php","line":82,"function":"exec","class":"Sabre\\DAV\\Server","type":"->","args":[]},{"file":"/var/www/nextcloud/remote.php","line":167,"args":["/var/www/nextcloud/apps/dav/appinfo/v1/webdav.php"],"function":"require_once"}],"File":"/var/www/nextcloud/apps/dav/lib/Connector/Sabre/File.php","Line":238,"CustomMessage":"--"},"userAgent":"--","version":"19.0.2.2"}

{"reqId":"Or0R2pucFGt5YGzIyZcI","level":3,"time":"2020-08-29T19:34:41+02:00","remoteAddr":"111.222.333.444","user":"john","app":"PHP","method":"PUT","url":"/remote.php/dav/uploads/john/4291849725/00000002","message":"Cannot modify header information - headers already sent by (output started at /var/www/nextcloud/3rdparty/sabre/http/lib/Sapi.php:132) at /var/www/nextcloud/apps/dav/lib/Connector/Sabre/File.php#680","userAgent":"Mozilla/5.0 (Windows) mirall/2.6.5stable-Win64 (build 20200710) (Nextcloud)","version":"19.0.2.2"}

Browser log

Browser log

Insert your browser log here, this could for example include:

a) The javascript console log
b) The network log
c) ...

[altosch]

In my case it stopped in itself. The messages were appearing in 2 days after upgrade. Nothing since. Don't know why and it seems we didn't lose any files. But there has to be something wrong because it's a PHP error.

[Shuvi-Hub]

i have the same proplem and because of that I can't upload files properly :((

[AndyXheli]

i have the same proplem and because of that I can't upload files properly :((

Yup me too

[Shuvi-Hub]

Ich habe das gleiche Problem und aus diesem Grund kann ich Dateien nicht richtig hochladen: ((

Yup ich auch

like 250 Kb/s and at the end an error/abort or freeze?

[yewkay]

I am having this error as well, it's generating quite a huge log file and masking out the other potentially important errors. Any resolution to this? On NC v19.0.2

Edit: Updated to v19.0.3 still experiencing the same issue

[altosch]

It's back again after upgrade to 19.0.3. The number after hash in the log message has changed from 680 to 683.

Cannot modify header information - headers already sent by (output started at /var/www/nextcloud/3rdparty/sabre/http/lib/Sapi.php:132) at /var/www/nextcloud/apps/dav/lib/Connector/Sabre/File.php#683

[csgt01]

I have the same Error on Linux, Mac and Android Clients.
I can't upload any files.

[papezg]

Same here no sync possible on any platform.

[xmzl]

The same thing happens here, regardless of the client operating system. However, using the oCluod client on Android, the Nexcluod server (19.0.3 on Debian 10) accepts the upload of those files that it refuses if uploaded from the Nextcloud client

[papezg]

By reverting client to 2.6.5 the sync works again. Avoid client 3.x for now.

[boyi01]

Same error in 19.0.3, even uploading via browser is not working...

I did little research, i can upload really smal files some kb, but imgaes some mb are not possible....