Bonapartism isnt an ideology (at least in the marxist sense), its a type of reactionary political movements. Its when someone coopts revolutionary aesthetics/ideology but uses them to stop progress/the revolution, under the excuse of uniting both left and right/x and y opposed groups to fight a perceived enemy. For example, Mao Zedong accused Nikita Khrushchev of bonapartism. This was because he proposed his “peaceful coexistence” and “ruling for the people” theories. This meant that the CPSU wasnt “the party of the working class and revolutionary peasantry” anymore, but “the party of the soviet people”, including the bourgeoisie, while the USSRs purpose wasnt to “promote a world communist revolution” anymore, but just to “peacefully coexist with the west”. The “perceived enemy” in this case was “stalinism”, which Khrushchev claimed was a tyrannical perversion of leninism that was destroying socialism. So as you see, Khrushchev was a total reactionary who promoted probourgeoisie views, but coated them in the revolutionary aesthetics and ideology of the Communist Party while inventing an imaginary enemy called “stalinism” to justify it. Thats bonapartism.

Another example of bonapartism is european social democracy. It adopts revolutionary aesthetics and ideology, by praising marxism and singing The Internationale, but then they promote right wing neoliberal and imperialist policies, under the excuse of “we must unite the best of socialism and of capitalism”.