High attrition and dropout rates are common in introductory programming courses. One of the reasons students drop out is loss of motivation due to the lack of feedback and proper assessment of their progress. Hence, a process-oriented approach is needed in assessing programming progress, which entails examining and measuring students' compilation behaviors and source codes. This paper reviews the elements of a process-oriented approach including previous studies that have used this approach. Specific metrics covered are Jadud's Error Quotient, the Watwin Score, Probabilistic Distance to Solution, Normalized Programming State Model, and the Repeated Error Density.