A SAS token consists of few parameters :
sv — Optional,tells version of the storage services to use.
ss — The signed services accessible with the SAS. Blob (b), Queue (q), Table (t), File (f).
srt — The signed resource types that are accessible with the SAS. Service (s): Access to service-level APIs; Container (c): Access to container-level APIs; Object (o): Access to object-level APIs for blobs, queue messages, table entities, and files.
sp — The signed permissions for the SAS. Read (r), Write (w), Delete (d), List (l), Add (a), Create (c), Update (u) and Process (p).
se — The time at which the shared access signature becomes invalid.
st — The time at which the SAS token becomes valid.
spr — The protocol permitted for a request made with the account SAS.
sig — Siganture is used to authorize your request to storage resorce
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