weight_name set to distance results in osrm::util::exception

[nocallaghan]

Issue extracting pbf when using the new weight_name set to distance.

osrm-extract british-isles-latest.osm.pbf 
[info] Using script profiles/car.lua
[info] Input file: british-isles-latest.osm.pbf
[info] Profile: car.lua
[info] Threads: 32
[info] Parsing in progress..
[STXXL-MSG] STXXL v1.4.1 (prerelease/Debug)
[STXXL-MSG] Disk '/tmp/stxxl' is allocated, space: 47683 MiB, I/O implementation: syscall queue=0 devid=0
[info] input file generated by osmium/1.5.0
[info] timestamp: n/a
[info] Found 3 turn restriction tags:
[info]   motorcar
[info]   motor_vehicle
[info]   vehicle
[info] Parsing finished after 49.0357 seconds
[info] Raw input contains 103929949 nodes, 12702569 ways, and 222996 relations
terminate called after throwing an instance of 'osrm::util::exception'
  what():  There are no edges remaining after parsing. (at src/extractor/extractor.cpp:231)
Aborted (core dumped)

Server: Ubuntu 16.04.1 LTS (GNU/Linux 4.4.0-53-generic x86_64)
Lua 5.2.4 Copyright (C) 1994-2015 Lua.org, PUC-Rio
OSRM is latest from master
The only change made to car.lua was to set weight_name to distance.

If I reset car.lua to the default option (duration), the extraction completes no problem.

[oxidase]

@nocallaghan the assertion is correct because if weight_name is not "duration" then weights for edges must be specified. This is not implemented in the current master, so all edges will have 0 weight and rejected.

Edge weights can be set in way_function via forward_rate and backward_rate properties. The properties have meaning similar to speed, but have units of meters per a weight unit instead of meters per second. The edge weight is computed as the edge distance divided by the rate, so using rate = 1 will result to weight = edge distance.

PR #3640 adds "distance" weight to way_function.

[nocallaghan]

Thank you @oxidase I'll try latest master out, I see #3640 was merged. Thanks for your other comment re: stxxl

[nocallaghan]

@oxidase that PR worked great, closing this. Thanks again