According to Wikipedia, lumpia, both fried and fresh versions, was brought by Chinese immigrants from China to Southeast Asia and became popular where they settled in Indonesia and the Philippines. This recipe is apparently no longer available online, but that's OK, it had some translation issues anyway. Here's what I used for the filling.
1 leek, thinly sliced
1 tbsp oyster sauce
1 tsp salt
1 clove garlic, minced
1/2 tsp sugar
1/2 tsp pepper
100 gms (about a cup) grated pumpkin
1/2 can sliced mushrooms, diced
75 gms (about a cup) bean sprouts
Grating the pumpkin was my idea and worked perfectly. I sauteed everything except the bean sprouts until all the vegetables were soft. Then added the bean sprouts and cooked just until they were wilted. I used about two tablespoons to fill each spring roll wrapper (they sell lumpia wrappers, but my store was out) and then rolled them up. There are several online videos showing the proper way to roll up lumpia, and when we lived on Guam, they even had classes in it. But since I wasn't going to deep fry them, which is the traditional way to cook lumpia, I didn't have to be so proper. The directions on the wrappers said they could be baked in the oven and that's what I did. I was the taster on these and, since lumpia is one of my favorite foods, deemed them great. I do think they would have probably been better deep fried, but then what isn't?