Update json docs for messages_by_df, new interval options. Remove

old references to the internal webserver.
This commit is contained in:
Oliver Jowett 2021-03-08 15:25:31 +08:00
parent a75296ae72
commit 1653ce9ca2
1 changed files with 8 additions and 7 deletions

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@ -7,15 +7,15 @@ about dump1090's operation to collectd for later graphing.
## Reading the json files ## Reading the json files
There are two ways to obtain the json files: dump1090-fa writes json files periodically to the location specified by the `--write-json` command line option.
These json files can then be exposed via a separate standalone webserver e.g. lighttpd.
* By HTTP from dump1090's internal webserver, which defaults to running on port 8080. The json is served from the data/ path, e.g. http://somehost:8080/data/aircraft.json The files are written periodically; for aircraft, typically once a second, for stats, once a minute.
* As a file in the directory specified by --write-json on dump1090's command line. These can be exposed via a The interval between file updates can be controlled by the `--write-json-every` and `--json-stats-every` options.
separate webserver. As these files are frequently updated, it's a good idea to put them in RAM rather than on disk. Package installs
default to putting the file under `/run`, which is in RAM.
The HTTP versions are always up to date. New versions of each file are written to a temporary file, then atomically renamed to the right path, so you should never see partial copies.
The file versions are written periodically; for aircraft, typically once a second, for stats, once a minute.
The file versions are updated to a temporary file, then atomically renamed to the right path, so you should never see partial copies.
Each file contains a single JSON object. The file formats are: Each file contains a single JSON object. The file formats are:
@ -164,3 +164,4 @@ Each period has the following subkeys:
* all: total tracks created * all: total tracks created
* single_message: tracks consisting of only a single message. These are usually due to message decoding errors that produce a bad aircraft address. * single_message: tracks consisting of only a single message. These are usually due to message decoding errors that produce a bad aircraft address.
* messages: total number of messages accepted by dump1090 from any source * messages: total number of messages accepted by dump1090 from any source
* messages_by_df: an array of integers where entry N (0..31) is the total number of messages accepted with downlink format (DF) = N.