- General Information
- Server Administration
- Mission Database
- Data Management
- Data Links
- Processors
- Commanding
- Services
- Security
- Web Interface
- Programs
Yamcs HTTP API
Yamcs Release Notes
Source Code Documentation
packet-viewer¶
Synopsis¶
Description¶
Use packet-viewer to extract parameters from packets by either loading a packet dump from disk (~ offline mode), or by decoding the raw data received from connecting to a Yamcs server (~ online mode).
In online mode, the splitting of packets is done by Yamcs Server and packet-viewer extracts parameters from each packet binary by using the same logic as Yamcs Server would.
In offline mode packet-viewer must in addition have access to a local MDB, and requires configuration so that it knows how to decode individual packets from a dump file. By default, dump files are assumed to contain concatenated CCSDS.
Options¶
- -h¶
Print a help message and exit.
- -l <N>¶
Limit the view to <N> packets.
In online mode only the last <N> packets will be visible. The default is 1000.
In offline mode only the first <N> packets of the file are displayed. There is no default, but for large dumps packet-viewer may become sluggish or run out of heap memory.
- -x <MDB>¶
Name of the applicable MDB as specified in the
etc/mdb.yaml
configuration file.This option is required in offline mode. In online mode the MDB defaults to that of the connected Yamcs instance.
- -i <INSTANCE>¶
In online mode, this indicates which instance's telemetry stream packet-viewer should connect to.
- -s <STREAM>¶
In online mode, this indicates which telemetry stream packet-viewer should connect to.
Default:
tm_realtime
.
- <FILE>¶
A local file which contains one or more packets. Typically concatenated CCSDS, but other file formats can be defined through configuration.
- <URL>¶
Base URL of a Yamcs server.
Examples¶
Offline mode:
packet-viewer -l 50 -x my-db packet-file
Online mode:
packet-viewer -l 50 -i simulator http://localhost:8090
Configuration Files¶
packet-viewer configuration files are placed in the etc/
directory. MDB files for local packet decoding are placed in mdb/
directory.
<packet-viewer>
|-- bin/
|-- etc/
| |-- mdb.yaml
| +-- packet-viewer.yaml
|-- lib/
+-- mdb/
|-- xtce1.xml
+-- xtce2.xml
mdb.yaml¶
Specifies one or more MDB configurations, which you can then choose from in order to extract parameters from a packet.
The MDB configuration structure can be copied from a etc/yamcs.instance.yaml
configuration file, but with a level on top which specifies the name visible in UI. In the following example, the user can choose between mymdb1 and mymdb2.
mymdb1:
- type: "xtce"
args:
file: "mdb/xtce1.xml"
mymdb2:
- type: "xtce"
args:
file: "mdb/xtce2.xml"
packet-viewer.yaml¶
packetPreprocessorClassName
/packetPreprocessorArgs
Configure a packet pre-processor. Configuration options are identical to preprocessor configuration of a data link on Yamcs Server.
fileFormats
List of supported file formats when opening a local packet dump file. The file format determines how to split the file in packets. Sub-keys:
name
Name of the format, as visible in UI.
packetInputStreamClassName
/packetInputStreamArgs
Configures a packet input stream. Configuration options are identical to packet input stream configuration of a data link on Yamcs Server.
rootContainer
Qualified name of the base container. Required if it cannot be uniquely determined.
Example:
packetPreprocessorClassName: org.yamcs.tctm.IssPacketPreprocessor
fileFormats:
- name: CCSDS Packets
packetInputStreamClassName: org.yamcs.tctm.CcsdsPacketInputStream
Packet Filter¶
Packet Viewer includes a filter box for filtering the displayed packets through arbitrary expressions.
For example, assume you have parameters /YSS/param1
and /YSS/param2
then you could write arbitrary expressions like:
param1 > 2
param2 == 3
param1 > 3 or param2 != 4
The left-hand side of a clause must always be the parameter. This may also be a fully qualified parameter name like /YSS/param1
.
The operator must be one of ==
, !=
, <
, <=
, >
, >=
or contains
. The latter is useful for string parameters.
The right-hand side of a clause may be a number or a string, and is compared to the engineering value of the parameter. The string may be surrounded by double quotes.
You can combine multiple clauses through the logical operators and
, or
, not
(or &&
, ||
, !
). Parentheses are allowed.
When done typing a filter, press ENTER to apply it.
Filter on packet properties¶
There are two hardcoded "parameters" that allow filtering on the global packet name or length:
packet.name == DHS
packet.length > 200
Filter on parameter presence¶
The operator and right-hand side of a clause are optional. This allows filtering on the presence of a parameter inside a packet. Example:
param1
Or, display only packets that do not include a parameter param1
:
!(param1)
Filter grammar¶
expr ::=or_expr
or_expr ::=and_expr
(or_op
and_expr
)* and_expr ::=unary_expr
(and_op
unary_expr
)* unary_expr ::=not_op
"("expr
")" | "("expr
")" |comparison
comparison ::=reference
[rel_op
literal
] reference ::=refchar
+ refchar ::=letter
|digit
| "/" | "_" | "-" | "[" | "]" | "." literal ::=string
|quoted_string
string ::=stringchar
+ quoted_string ::= '"' [string
] '"' stringchar ::=letter
|digit
| ":" | "_" | "/" | "-" letter ::= "a"..."Z" digit ::= "0"..."9" rel_op ::=eq_op
|ne_op
|gt_op
|lt_op
|ge_op
|le_op
|matches_op
| "contains" eq_op ::= "eq" | "==" ne_op ::= "ne" | "!=" gt_op ::= "gt" | ">" lt_op ::= "lt" | "<" ge_op ::= "ge" | ">=" le_op ::= "le" | "<=" matches_op ::= "matches" | "~" and_op ::= "and" | "&&" or_op ::= "or" | "||" not_op ::= "not" | "!"