[bitbake-devel] [PATCH] fetch2/npm: fix parsing multiple matching packages

[mpvader]

Replace the self-implemented parser with loading the complete json and then
taking the last element from it.

This fixes an error fetching the lex-parser package, as a dependency of, for
example, jison. Reproduce the error with this command:

devtool add "npm://registry.npmjs.org;name=jison;version=0.4.18"

_parse_view() didn't properly parse the npm view result [1], resulting in
an Exception in the subsequent json.loads() function:
Exception: ValueError: Extra data: line 57 column 4 - line 296 column 2 (char 5874 - 29698)

[1] npm view lex-parser@'0.1.x' --json --registry http://registry.npmjs.org

Signed-off-by: mpvader <mvader at victronenergy.com>
---
 lib/bb/fetch2/npm.py | 29 ++++++++---------------------
 1 file changed, 8 insertions(+), 21 deletions(-)

diff --git a/lib/bb/fetch2/npm.py b/lib/bb/fetch2/npm.py
index b5f148c..e257355 100644
--- a/lib/bb/fetch2/npm.py
+++ b/lib/bb/fetch2/npm.py
@@ -146,25 +146,6 @@ class Npm(FetchMethod):
 
         self._unpackdep(ud, ud.pkgname, workobj, unpackdir, dldir, d)
 
-    def _parse_view(self, output):
-        '''
-        Parse the output of npm view --json; the last JSON result
-        is assumed to be the one that we're interested in.
-        '''
-        pdata = None
-        outdeps = {}
-        datalines = []
-        bracelevel = 0
-        for line in output.splitlines():
-            if bracelevel:
-                datalines.append(line)
-            elif '{' in line:
-                datalines = []
-                datalines.append(line)
-            bracelevel = bracelevel + line.count('{') - line.count('}')
-        if datalines:
-            pdata = json.loads('\n'.join(datalines))
-        return pdata
 
     def _getdependencies(self, pkg, data, version, d, ud, optional=False, fetchedlist=None):
         if fetchedlist is None:
@@ -175,9 +156,15 @@ class Npm(FetchMethod):
         logger.debug(2, "Calling getdeps on %s" % pkg)
         fetchcmd = "npm view %s --json --registry %s" % (pkgfullname, ud.registry)
         output = runfetchcmd(fetchcmd, d, True)
-        pdata = self._parse_view(output)
-        if not pdata:
+        if not output:
             raise FetchError("The command '%s' returned no output" % fetchcmd)
+        pdata = json.loads(output)
+
+        # npm registry will return multiple dicts in a list when there is more than one matching
+        # version. Take the last one.
+        if isinstance(pdata, list):
+            pdata = pdata[-1]
+
         if optional:
             pkg_os = pdata.get('os', None)
             if pkg_os:
-- 
2.7.4