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Apache Camel sends internal headers to HTTP calls

Apache Camel by default translates all the headers present in a message to HTTP headers.
This is very useful, but since many components also use headers for internal state, there can be leak of internal information on external HTTP calls.
Example, if the job was started using a timer / cron, we end up sending the following HTTP headers on the wire:
http-outgoing-1 >> fireTime: Mon Dec 28 10:14:00 CET 2020
http-outgoing-1 >> jobDetail: JobDetail 'Camel_camel-1.sync': jobClass: 'org.apache.camel.component.quartz.CamelJob concurrentExectionDisallowed: false persistJobDataAfterExecution: false isDurable: false requestsRecovers: false
http-outgoing-1 >> jobInstance: org.apache.camel.component.quartz.CamelJob#4ff90d52
http-outgoing-1 >> jobRunTime: -1
http-outgoing-1 >> mergedJobDataMap: org.quartz.JobDataMap#2338bfe0
http-outgoing-1 >> nextFireTime: Mon Dec 28 10:15:00 CET 2020
http-outgoing-1 >> refireCount: 0
http-outgoing-1 >> scheduledFireTime: Mon Dec 28 10:14:00 CET 2020
http-outgoing-1 >> scheduler: org.quartz.impl.StdScheduler#17a5f565
http-outgoing-1 >> trigger: Trigger 'Camel_camel-1.syncJob': triggerClass: 'org.quartz.impl.triggers.CronTriggerImpl calendar: 'null' misfireInstruction: 1 nextFireTime: Mon Dec 28 10:15:00 CET 2020
http-outgoing-1 >> triggerGroup: Camel_camel-1
http-outgoing-1 >> triggerName: syncJob
... (actual needed HTTP headers:)
http-outgoing-1 >> Connection: Keep-Alive
http-outgoing-1 >> User-Agent: Apache-HttpClient/4.5.12 (Java/11.0.6)
I know that I can remove all headers before attempting HTTP call.
Since my other routes also add my internal headers which I need, it is not simple to just remove all "junk" headers for me at point before sending the call, but keeping my internal ones (which also end up in the HTTP call btw.).
I am aware that I can use properties for this.
I am aware that I can disable headers of message to automatically be added as HTTP headers. In this case I am not sure if I need to add manually the headers which are needed for HTTP (like user-agent).
Also other frequent misuse of the headers is if you make 2 HTTP calls and forget to clear the headers,
the output headers of the first call will become input headers of the first.
Anyone found a good workaround how to avoid this issue?

This is how HTTP-based endpoints (camel-http, camel-http4, camel-jetty, camel-restlet, camel-cxf, camel-cxfrs) process headers by default (you can customize this behavior using HeaderFilterStrategy).
Consumer: creates an In message with CamelHttp* headers which record the status of the incoming message, all of the HTTP headers from the original message, and URL options (Jetty only).
Producer: converts the Exchange it to the target message format with CamelHttp* headers to control the behaviour of the HTTP producer endpoint, Camel* headers are filtered out because they are intended for internal use, and all other headers are converted to HTTP headers with the exception of content-length, content-type, cache-control, connection, date, pragma, trailer, transfer-encoding, upgrade, via, warning.
it is not simple to just remove all "junk" headers for me at point before sending the call, but keeping my internal ones (which also end up in the HTTP call btw.).
You could prefix your internal one with Camel to avoid leaking them as HTTP headers. If you need some of them as HTTP headers, you can manually to the mapping to a different key before the call.
In this case I am not sure if I need to add manually the headers which are needed for HTTP (like user-agent).
You don't need them.
Also other frequent misuse of the headers is if you make 2 HTTP calls and forget to clear the headers, the output headers of the first call will become input headers of the first.
In this case, you should at least remove the control headers with .removeHeaders("CamelHttp*).

Spring Oauth2 CORS issue

I set CORS to allow few custom headers. Below is the Response Header -
Response Headers { "Date": "Mon, 14 Mar 2016 10:11:59 GMT",
"Server": "Apache-Coyote/1.1", "Transfer-Encoding": "chunked",
"Access-Control-Max-Age": "3600", "Access-Control-Allow-Methods":
"POST, GET, OPTIONS, DELETE, PUT", "Content-Type":
"application/json", "Access-Control-Allow-Origin":
"*",
"Access-Control-Allow-Credentials": "true",
"Access-Control-Allow-Headers": "X-Requested-With, Authorization,
Content-Type, Authorization_Code, User_Credentials,
Client_Credentials" }
Above response header should mean that API can be consumed from all the origins with following headers: Authorization, Content-Type, Authorization_Code, User_Credentials, Client_Credentials
I can pass all headers and consume APIs from all origins.
PROBLEM -
Requests with Authorization APIs are not being allowed. Authorization is a header with which Oauth token is passed like this - Authorizatio = Bearer ct45tg4g3rf3rfr5freg34gerfgr3gf (Bearer token).
corsclient.js:609 OPTIONS http://54.200.113.97:8080/supafit-api/users
sendRequest # corsclient.js:609(anonymous function) #
corsclient.js:647b.event.dispatch # jquery-1.9.1.min.js:3v.handle #
jquery-1.9.1.min.js:3
/client#?client_method=GET&client_credentials=false&client_headers=Authoriz…nable=true&server_status=200&server_credentials=false&server_tabs=remote:1
XMLHttpRequest cannot load
http://54.200.113.97:8080/supafit-api/users. Response to preflight
request doesn't pass access control check: No
'Access-Control-Allow-Origin' header is present on the requested
resource. Origin 'http://client.cors-api.appspot.com' is therefore not
allowed access. The response had HTTP status code 401.
EDIT:
Here is the Rest Client test of that API -
Response Header -
Server: Apache-Coyote/1.1
Cache-Control: no-cache, no-store, max-age=0, must-revalidate
Pragma: no-cache
Expires: 0
X-XSS-Protection: 1; mode=block
X-Frame-Options: DENY
X-Content-Type-Options: nosniff
Access-Control-Allow-Origin: http://client.cors-api.appspot.com
Access-Control-Allow-Methods: POST, GET, OPTIONS, DELETE, PUT
Access-Control-Max-Age: 3600
Access-Control-Allow-Credentials: true
Access-Control-Allow-Headers: X-Requested-With
Access-Control-Allow-Headers: Authorization
Access-Control-Allow-Headers: Content-Type
Access-Control-Allow-Headers: Authorization_Code
Access-Control-Allow-Headers: User_Credentials
Access-Control-Allow-Headers: Client_Credentials
Content-Type: application/json
Transfer-Encoding: chunked
Date: Mon, 14 Mar 2016 11:19:42 GMT Raw JSON
JSON Response Body -
{ "id":78, "userId":"3465434567", "coachId":null,
"name":"XDCDSC", "dob":null, "email":"puneetpandey37#gmail.com",
"imageURL":"https://lh5.googleusercontent.com/-TcTQeitAvag/AAAAAAAAAAI/AAA/4pamurzO1a4/photo.jpg",
"gender":null, "userPhysic":null, "userTypeId":1,
"dietitanId":null, "alternateEmailId":null,
"yearsOfExperience":null, "lastExperience":null,
"languagesKnown":null, "aboutYourself":null,
"coreCompetence":null, "fieldOfWork":null, "userAddresses":[
{
"id":1,
"userId":78,
"locationId":1,
"address":"EC",
"landmark":"Near BN",
"phoneNumber":null,
"addressType":"Home"
} ], "phoneNumbers":[
] }

The response had HTTP status code 401.
Your server needs authentification for the Preflight Request, but the client removes credentials as CORS specification says:
Otherwise, make a preflight request. Fetch the request URL from origin source origin using referrer source as override referrer source with the manual redirect flag and the block cookies flag set, using the method OPTIONS, and with the following additional constraints:
Include an Access-Control-Request-Method header with as header field value the request method (even when that is a simple method).
If author request headers is not empty include an Access-Control-Request-Headers header with as header field value a comma-separated list of the header field names from author request headers in lexicographical order, each converted to ASCII lowercase (even when one or more are a simple header).
Exclude the author request headers.
Exclude user credentials.
Exclude the request entity body.
You have to change your server, to allow anonymous access of Preflight Request.

OneDrive API download in parts

I am currently trying to develop a Java based app to access OneDrive.
Today i tried to implement the download as described here: https://dev.onedrive.com/items/download.htm
I wanted to use the range parameter, to offer the user the capability to pause large downloads. But no matter how i send the parameter be at within the HTTP-Request header or in the URL as a GET-Parameter it will always send me the complete file.
Things i tried so far:
https:/ /api.onedrive.com/v1.0/drive/items/***/content?range=0-8388607
(OAuth via HTTP header)
https:/ /api.onedrive.com/v1.0/drive/items/***/content:
Header: Authorization: ***
range: 0-8388607
https:/ /api.onedrive.com/v1.0/drive/items/***/content:
Header: Authorization: ***
range: bytes=0-8388607
I also tried Content-Range and various variations on lower and upper case without success. Any reason why this dose not work?
PS.:
The links a broken because i am using a new account that only allows 2 links per post, I am aware that ther is a space between the two // in my post ;)

Requesting the range of the file is supported. You might want to use fiddler or some other tool to see if the original headers are being passed after the 302 redirect is performed. Below are the HTTP requests and responses when I provide the range header which is being passed on after the 302 redirect occurs. You'll notice that a HTTP 206 partial content response is returned. Additionally, to resume a download, you can use "Range: bytes=1025-" or whatever the last byte received was. I hope that helps.
GET https://api.onedrive.com/v1.0/drive/items/item-id/content HTTP/1.1
Authorization: Bearer
Range: bytes=0-1024
Host: api.onedrive.com
HTTP/1.1 302 Found
Content-Length: 0
Location: https://kplnyq.dm2302.livefilestore.com/edited_location
Other headers removed
GET https://kplnyq.dm2302.livefilestore.com/edited_location
Range: bytes=0-1024
Host: kplnyq.dm2302.livefilestore.com
HTTP/1.1 206 Partial Content
Cache-Control: public
Content-Length: 1025
Content-Type: audio/mpeg
Content-Location: https://kplnyq.dm2302.livefilestore.com/edited_location
Content-Range: bytes 0-1024/4842585
Expires: Tue, 11 Aug 2015 21:34:52 GMT
Last-Modified: Mon, 12 Dec 2011 21:33:41 GMT
Accept-Ranges: bytes
Server: Microsoft-HTTPAPI/2.0
Other headers removed

Cache Control gets ignored

I am currently working with Retrofit and Okhttp and I am trying to cache some GET responses.
My Code is:
OkHttpClient okHttpClient = new OkHttpClient();
File cacheDir = new File(System.getProperty("java.io.tmpdir"),
"ddcache");
HttpResponseCache cache = new HttpResponseCache(cacheDir, 2024);
okHttpClient.setResponseCache(cache);
OkClient cl=new OkClient(okHttpClient);
restAdapter = new RestAdapter.Builder().setEndpoint(API_URL)
.setLogLevel(RestAdapter.LogLevel.FULL)
.setClient(cl).build();
And the Log shows this header:
HTTP/1.1 200 OK
Cache-Control: max-age=7200
Connection: Keep-Alive
Content-Type: text/html
Date: Tue, 18 Mar 2014 18:38:16 GMT
Keep-Alive: timeout=3, max=100
OkHttp-Received-Millis: 1395167895452
OkHttp-Response-Source: NETWORK 200
OkHttp-Sent-Millis: 1395167895378
Server: Apache/2.2.26 (Unix)
Transfer-Encoding: chunked
X-Powered-By: PHP/5.3.28
I check the response by returning the Server Unix Time on every call and it always returns a new one which means the
Cache-Control: max-age=7200
gets totally ignored
The Journal File in the Cache gets also updated with "CLEAN" and "DIRTY" notes, but nothing gets cached.
Is there something obvious I do not see?

I think I had a similar problem. The size of the cache is set in kilobytes and you are setting it to only 2024 kilobytes. That not enough space for almost anything. Try setting it to "10L * 1024 * 1024" (10Mb) and see if that helps.

http: conditional get does not give a chance to refresh headers without sending body again

I don't know if this is a bug or a feature in the http spec, or I am not understanding things ok.
I have a resource that changes at most once a week, at the week's beginning. If it didn't change, then the previous week's resource continues to be valid for the whole week.
(For all our tests we have modified the one week period for five minutes, but I think our observations are still valid).
First we send the resource with the header Expires: next Monday. The whole week the browser retrieves from the cache. If on Monday we have a new resource then it is retrieved with its new headers and everything is ok.
The problem occurs when the resource is not renewed. In response to the conditional get our app (Java+Tomcat) sends new headers with Expires: next Monday but without the body. But our frontend server (apache) removes this header, because the spec says you should not send new headers if the resource did not change. So now forever (until the resource changes) the browser will send a conditional get when we would like it to continue serving straight from the cache.
Is there a spec compliant way to update the headers without updating the body? (or sending it again)
And subquestion: how to make apache pass along tomcat's headers?

Just a Expires header is not enough. According to RFC 2616 section 13.3.4, a server needs to respond with two headers, Last-Modified and ETag, to do conditional GET right:
In other words, the preferred behavior for an HTTP/1.1 origin server is to send both a strong entity tag and a Last-Modified value.
And if the client is HTTP/1.1 compliant, it should send If-Modified-Since. Then the server is supposed to respond as following (quoted from Roy Fielding's proposal to add conditional GET):
If resource is inaccessible (for whatever reason), then the server should return a 4XX message just like it does now.
If resource no longer exists, the server should return a 404 Not Found response (i.e. same as now).
If resource is accessible but its last modification date is earlier (less than) or equal to the date passed, the server should return a 304 Not Modified message (with no body).
If resource is accessible and its last modification date is later than the date passed, the server should return a 200 OK message (i.e. same as now) with body.
So, I guess you don't need to configure Apache and/or Tomcat the way you described. You need to make your application HTTP/1.1 compliant.

Try sending a valid HTTP-Date for the Expires header?

One way to solve the problem is using separate URIs for each week. The canonical url redirects to the appropriate url for the week, and instructs the browser to cache the redirect for a week. Also, URLs that have a date in them will instruct the browser to cache forever.
Canonical URL : /path/to/resource
Status Code : 301
Location : /path/to/resource/12-dec or /path/to/resource/19-dec
Expires : Next Monday
Week 1 : /path/to/resource/12-dec
Status code : 200
Expires : Never
Week 2 : /path/to/resource/19-dec
Status code : 200
Expires : Never
When the cache expires on Monday, you just send a redirect response. You either send last weeks URL or this weeks, but you never send the entire response body.
With this approach, you have eliminated conditional gets. You have also made your resources "unmodifiable-once-published", and you also get versioned resources.
The only caveat - redirects aren't cached by all browsers even though the http spec requires them to do so. Notably IE8 and below don't cache. For details, look at the column "cache browser redirects" in browserscope.

The Expires header was basically deprecated with HTTP 1.1; use Cache-Control: max-age instead.
Make sure you are including Last-Modified.
It's optional, but you may also want to specify Cache-Control: must-revalidate, to make sure intermediate proxies don't deliver potentially stale content.
You don't need to set ETag.
Example request:
GET http://localhost/images/logo.png HTTP/1.1
Accept: image/png, image/svg+xml, image/*;q=0.8, */*;q=0.5
Referer: http://localhost/default.aspx
Accept-Language: en-US
User-Agent: Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0)
Accept-Encoding: gzip, deflate
Host: localhost
Connection: Keep-Alive
The response includes the requested content:
HTTP/1.1 200 OK
Cache-Control: max-age=10
Content-Type: image/png
Last-Modified: Sat, 21 Feb 2009 11:28:18 GMT
Accept-Ranges: bytes
Date: Sun, 18 Dec 2011 05:48:34 GMT
Content-Length: 2245
Requests made before the 10 second timeout are resolved from cache, with no HTTP request. After the timeout:
GET http://localhost/images/logo.png HTTP/1.1
Accept: image/png, image/svg+xml, image/*;q=0.8, */*;q=0.5
Referer: http://localhost/default.aspx
Accept-Language: en-US
User-Agent: Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0)
Accept-Encoding: gzip, deflate
Connection: Keep-Alive
If-Modified-Since: Sat, 21 Feb 2009 11:28:18 GMT
Host: localhost
The response is just headers, without content:
HTTP/1.1 304 Not Modified
Cache-Control: max-age=10
Last-Modified: Sat, 21 Feb 2009 11:28:18 GMT
Accept-Ranges: bytes
Date: Sun, 18 Dec 2011 05:49:04 GMT
Subsequent requests are again resolved from the browser's cache until the specified cache expiration time.