PureBasic

Get RSA Public Key in JWK Format (JSON Web Key)

See more JSON Web Signatures (JWS) Examples

Demonstrates how to get an RSA public key in JWK (JSON Web Key) format.

Note: This example requires Chilkat v9.5.0.66 or later.

PureBasic

IncludeFile "CkStringBuilder.pb"
IncludeFile "CkJsonObject.pb"
IncludeFile "CkPublicKey.pb"

Procedure ChilkatExample()

    success.i = 0

    ; Note: This example requires Chilkat v9.5.0.66 or later.

    ; Load a PEM file into memory.
    sbPem.i = CkStringBuilder::ckCreate()
    If sbPem.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success = CkStringBuilder::ckLoadFile(sbPem,"qa_data/pem/rsa_public.pem","utf-8")
    If success <> 1
        Debug "Failed to load PEM file."
        CkStringBuilder::ckDispose(sbPem)
        ProcedureReturn
    EndIf

    ; Load the PEM into a public key object.
    pubKey.i = CkPublicKey::ckCreate()
    If pubKey.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success = CkPublicKey::ckLoadFromString(pubKey,CkStringBuilder::ckGetAsString(sbPem))
    If success <> 1
        Debug CkPublicKey::ckLastErrorText(pubKey)
        CkStringBuilder::ckDispose(sbPem)
        CkPublicKey::ckDispose(pubKey)
        ProcedureReturn
    EndIf

    ; Get the public key in JWK format:
    jwk.s = CkPublicKey::ckGetJwk(pubKey)

    ; The GetJwk method will return the JWK in the most compact JSON format possible,
    ; as a single line with no extra whitespace.  To get a more human-readable JWK (for this example),
    ; load into a Chilkat JSON object and emit non-compact:

    json.i = CkJsonObject::ckCreate()
    If json.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkJsonObject::ckLoad(json,jwk)
    CkJsonObject::setCkEmitCompact(json, 0)
    Debug "RSA Public Key in JWK format:"
    Debug CkJsonObject::ckEmit(json)

    ; Sample output:
    ; { 
    ;   "kty": "RSA",
    ;   "n": "33TqqLR3eeUmDtHS89qF3p4MP7Wfqt2Zjj3lZjLjjCGDvwr9cJNlNDiuKboODgUiT4ZdPWbOiMAfDcDzlOxA04DDnEFGAf-kDQiNSe2ZtqC7bnIc8-KSG_qOGQIVaay4Ucr6ovDkykO5Hxn7OU7sJp9TP9H0JH8zMQA6YzijYH9LsupTerrY3U6zyihVEDXXOv08vBHk50BMFJbE9iwFwnxCsU5-UZUZYw87Uu0n4LPFS9BT8tUIvAfnRXIEWCha3KbFWmdZQZlyrFw0buUEf0YN3_Q0auBkdbDR_ES2PbgKTJdkjc_rEeM0TxvOUf7HuUNOhrtAVEN1D5uuxE1WSw",
    ;   "e": "AQAB"
    ; }

    ; Additional information can be added like this:
    CkJsonObject::ckAppendString(json,"use","enc")
    CkJsonObject::ckAppendString(json,"kid","123ABC")

    ; Now examine the JSON:
    Debug CkJsonObject::ckEmit(json)

    ; { 
    ;   "kty": "RSA",
    ;   "n": "33TqqLR3eeUmDtHS89qF3p4MP7Wfqt2Zjj3lZjLjjCGDvwr9cJNlNDiuKboODgUiT4ZdPWbOiMAfDcDzlOxA04DDnEFGAf-kDQiNSe2ZtqC7bnIc8-KSG_qOGQIVaay4Ucr6ovDkykO5Hxn7OU7sJp9TP9H0JH8zMQA6YzijYH9LsupTerrY3U6zyihVEDXXOv08vBHk50BMFJbE9iwFwnxCsU5-UZUZYw87Uu0n4LPFS9BT8tUIvAfnRXIEWCha3KbFWmdZQZlyrFw0buUEf0YN3_Q0auBkdbDR_ES2PbgKTJdkjc_rEeM0TxvOUf7HuUNOhrtAVEN1D5uuxE1WSw",
    ;   "e": "AQAB",
    ;   "use": "enc",
    ;   "kid": "123ABC"
    ; }


    CkStringBuilder::ckDispose(sbPem)
    CkPublicKey::ckDispose(pubKey)
    CkJsonObject::ckDispose(json)


    ProcedureReturn
EndProcedure