Improve apache input docs (#3120)

plugins/inputs/apache/README.md

@@ -1,55 +1,84 @@
-# Telegraf plugin: Apache
+# Apache Input Plugin
 
-#### Plugin arguments:
-- **urls** []string: List of apache-status URLs to collect from. Default is "http://localhost/server-status?auto".
-- **username** string: Username for HTTP basic authentication
-- **password** string: Password for HTTP basic authentication
-- **timeout** duration: time that the HTTP connection will remain waiting for response. Default 4 seconds ("4s")
+The Apache plugin collects server performance information using the [`mod_status`](https://httpd.apache.org/docs/2.4/mod/mod_status.html) module of the [Apache HTTP Server](https://httpd.apache.org/).
 
-##### Optional SSL Config
+Typically, the `mod_status` module is configured to expose a page at the `/server-status?auto` location of the Apache server.  The [ExtendedStatus](https://httpd.apache.org/docs/2.4/mod/core.html#extendedstatus) option must be enabled in order to collect all available fields.  For information about how to configure your server reference the [module documenation](https://httpd.apache.org/docs/2.4/mod/mod_status.html#enable).
 
-- **ssl_ca** string: the full path for the SSL CA certicate
-- **ssl_cert** string: the full path for the SSL certificate
-- **ssl_key** string: the full path for the key file
-- **insecure_skip_verify** bool: if true HTTP client will skip all SSL verifications related to peer and host. Default to false
+### Configuration:
 
-#### Description
+```toml
+# Read Apache status information (mod_status)
+[[inputs.apache]]
+  ## An array of URLs to gather from, must be directed at the machine
+  ## readable version of the mod_status page including the auto query string.
+  ## Default is "http://localhost/server-status?auto".
+  urls = ["http://localhost/server-status?auto"]
 
-The Apache plugin collects from the /server-status?auto URL. See
-[apache.org/server-status?auto](http://www.apache.org/server-status?auto) for an
-example. And
-[here](http://httpd.apache.org/docs/2.2/mod/mod_status.html) for the apache
-mod_status documentation.
+  ## Credentials for basic HTTP authentication.
+  # username = "myuser"
+  # password = "mypassword"
 
-# Measurements:
+  ## Maximum time to receive response.
+  # response_timeout = "5s"
 
-Meta:
-- tags: `port=<port>`, `server=url`
+  ## Optional SSL Config
+  # ssl_ca = "/etc/telegraf/ca.pem"
+  # ssl_cert = "/etc/telegraf/cert.pem"
+  # ssl_key = "/etc/telegraf/key.pem"
+  ## Use SSL but skip chain & host verification
+  # insecure_skip_verify = false
+```
 
-- apache_TotalAccesses
-- apache_TotalkBytes
-- apache_CPULoad
-- apache_Uptime
-- apache_ReqPerSec
-- apache_BytesPerSec
-- apache_BytesPerReq
-- apache_BusyWorkers
-- apache_IdleWorkers
-- apache_ConnsTotal
-- apache_ConnsAsyncWriting
-- apache_ConnsAsyncKeepAlive
-- apache_ConnsAsyncClosing
+### Measurements & Fields:
 
-### Scoreboard measurements
+- apache
+  - BusyWorkers (float)
+  - BytesPerReq (float)
+  - BytesPerSec (float)
+  - ConnsAsyncClosing (float)
+  - ConnsAsyncKeepAlive (float)
+  - ConnsAsyncWriting (float)
+  - ConnsTotal (float)
+  - CPUChildrenSystem (float)
+  - CPUChildrenUser (float)
+  - CPULoad (float)
+  - CPUSystem (float)
+  - CPUUser (float)
+  - IdleWorkers (float)
+  - Load1 (float)
+  - Load5 (float)
+  - Load15 (float)
+  - ParentServerConfigGeneration (float)
+  - ParentServerMPMGeneration (float)
+  - ReqPerSec (float)
+  - ServerUptimeSeconds (float)
+  - TotalAccesses (float)
+  - TotalkBytes (float)
+  - Uptime (float)
 
-- apache_scboard_waiting
-- apache_scboard_starting
-- apache_scboard_reading
-- apache_scboard_sending
-- apache_scboard_keepalive
-- apache_scboard_dnslookup
-- apache_scboard_closing
-- apache_scboard_logging
-- apache_scboard_finishing
-- apache_scboard_idle_cleanup
-- apache_scboard_open
+The following fields are collected from the `Scoreboard`, and represent the number of requests in the given state:
+
+- apache
+  - scboard_closing (float)
+  - scboard_dnslookup (float)
+  - scboard_finishing (float)
+  - scboard_idle_cleanup (float)
+  - scboard_keepalive (float)
+  - scboard_logging (float)
+  - scboard_open (float)
+  - scboard_reading (float)
+  - scboard_sending (float)
+  - scboard_starting (float)
+  - scboard_waiting (float)
+
+### Tags:
+
+- All measurements have the following tags:
+    - port
+    - server
+
+### Example Output:
+
+```
+apache,port=80,server=debian-stretch-apache BusyWorkers=1,BytesPerReq=0,BytesPerSec=0,CPUChildrenSystem=0,CPUChildrenUser=0,CPULoad=0.00995025,CPUSystem=0.01,CPUUser=0.01,ConnsAsyncClosing=0,ConnsAsyncKeepAlive=0,ConnsAsyncWriting=0,ConnsTotal=0,IdleWorkers=49,Load1=0.01,Load15=0,Load5=0,ParentServerConfigGeneration=3,ParentServerMPMGeneration=2,ReqPerSec=0.00497512,ServerUptimeSeconds=201,TotalAccesses=1,TotalkBytes=0,Uptime=201,scboard_closing=0,scboard_dnslookup=0,scboard_finishing=0,scboard_idle_cleanup=0,scboard_keepalive=0,scboard_logging=0,scboard_open=100,scboard_reading=0,scboard_sending=1,scboard_starting=0,scboard_waiting=49 1502489900000000000
+```

plugins/inputs/apache/apache.go

@@ -34,15 +34,17 @@ type Apache struct {
 }
 
 var sampleConfig = `
-  ## An array of Apache status URI to gather stats.
+  ## An array of URLs to gather from, must be directed at the machine
+  ## readable version of the mod_status page including the auto query string.
   ## Default is "http://localhost/server-status?auto".
   urls = ["http://localhost/server-status?auto"]
-  ## user credentials for basic HTTP authentication
-  username = "myuser"
-  password = "mypassword"
 
-  ## Timeout to the complete conection and reponse time in seconds
-  response_timeout = "25s" ## default to 5 seconds
+  ## Credentials for basic HTTP authentication.
+  # username = "myuser"
+  # password = "mypassword"
+
+  ## Maximum time to receive response.
+  # response_timeout = "5s"
 
   ## Optional SSL Config
   # ssl_ca = "/etc/telegraf/ca.pem"