Cannot re-import exported rdf/schema with special-character predicate names

[danielmai]

If you suspect this could be a bug, follow the template.

• What version of Dgraph are you using?
  v1.0.12-rc5

• Have you tried reproducing the issue with latest release?
  yes

• What is the hardware spec (RAM, OS)?
  n/a

• Steps to reproduce the issue (command/config used to run Dgraph).

1. Run a Dgraph cluster.
2. Run a mutation with predicates that have special characters:

{
  set {
    _:a <pred/slash> "1" .
    _:b <pred*star> "2" .
  }
}

3. Export the data with /admin/export. The schema file has the following lines:

pred*star:default . 
pred/slash:default . 

4. Run the live loader with the rdf and schema file from the export:

$ dgraph live -r ./g01.rdf.gz -s ./g01.schema.gz -d localhost:9080 -z localhost:5080
...
Processing ./g01.schema.gz
Error while processing schema file "./g01.schema.gz": rpc error: code = Unknown desc = Missing colon

We can repeat the same steps with IRI-named predicates which results in a similar but different error. e.g. this mutation:

{
  set {
    _:c <故障> "3" .
  }
}

The exported schema file will contain:

故障:default . 

And the live load will show this error:

Processing ./g01.schema.gz
Error while processing schema file "./dgraph.r48.u0123.0232/g01.schema.gz": rpc error: code = Unknown desc = while lexing 故障:default . 

: Invalid schema. Unexpected 故

• Expected behavior

I expect that an export can be imported as-is without any modifications.

• Additional comments

The schema update works if I modify the exported schema file by surrounding the predicate names with <>.

<pred*star>:default . 
<pred/slash>:default . 
<故障>:default .