patchYamlCfg.py

import yaml, os, sys, datetime


# slightly adapted from http://stackoverflow.com/a/44512
def merge(d1, d2, merge_fn=lambda x,y:y):
    result = dict(d1)
    for k,v in d2.iteritems():
        if k in result:            
            if isinstance(result[k], dict):
                print "going in for " + k
                result[k] = merge_fn(result[k], v)
            else:                
                print "setting " + k + " with " + str(v)
                result[k] = v
        else:
            print "setting " + k + " with " + str(v)
            result[k] = v
    return result


if len(sys.argv) <= 2 :
    print "fileToPath patch"
    sys.exit(2)                     
 
inputFilename = sys.argv[1]
patchFilename = sys.argv[2]

print "Patching " + inputFilename + " with " + patchFilename

with open(inputFilename) as f:
    originalCfg = yaml.load(f)

with open(inputFilename + ".reformatted", "w") as f:
    yaml.dump(originalCfg, f, default_flow_style=False)

with open(patchFilename) as f:
    patchCfg = yaml.load(f)

os.rename(inputFilename, inputFilename + datetime.datetime.now().isoformat())

#for level1Keys in patchCfg.keys():
    #for level2Keys in level1Keys.keys():
        #if level1Keys not  in originalCfg
            #all[k].append(a[k])
        #else:
            #all[k] = a[k]

rec_merge = lambda x, y: merge(x, y, rec_merge)

patchedConfig = merge (originalCfg, patchCfg, rec_merge)


with open(inputFilename, "w") as f:
    yaml.dump(patchedConfig, f, default_flow_style=False)