Name a couple of literary techniques that are used in the poem 'Valentine,' by Carol Ann Duffy?

In Carol Ann Duffy's poem 'Valentine,' she regularly uses metaphor to demonstrate the ways in which an onion can represent the romance of a relationship. In the second line of the first stanza, she describes an onion as a ''moon wrapped in brown paper.'' By saying that the onion IS this rather than IS LIKE this, she has figuratively turned the onion into the moon. On the fourth line however, she uses simile to suggest that the light it promises is 'like' the ''careful undressing of love.''
She also uses personification in fourteenth line, describing the ''fierce kiss.'' This personification gives the onion the actions of a person. This shocks the reader due to the nature of an onion and what an onion would normally represent (bad smell, painful watering eyes, etc.)