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PureBasic Requires Chilkat v11.7.0+

Box: Resolve a File Version by Name and Verify the Download

See more Box Examples

Run the reusable setup once per HttpCurl object, then select names and execute the operation. The setup is repeated here only to make this published example independently runnable. One target request requires file_id and file_version_id. The engine uses AddOutput2 for name lookups and AddOutput for version/SHA-1 metadata, then downloads that version to local_path and verifies its digest.

See the Box API guide for setup and the complete workflow.

Chilkat PureBasic Downloads

PureBasic
IncludeFile "CkStringBuilder.pb"
IncludeFile "CkHttpCurl.pb"
IncludeFile "CkCrypt2.pb"

Procedure ChilkatExample()

    success.i = 0

    ;  Requires Chilkat 11.7.0 or later and a previously unlocked Chilkat bundle.
    ;  See Global Unlock Sample.
    ;  Guide: Box API Guide.

    success = 0

    ;  BEGIN ONE-TIME SETUP
    ;  This block is repeated so each published example can run on its own.
    ;  In an application, run the setup example once and pass the SAME curl object
    ;  to operation code below. Do not recreate it for every operation.
    ;  See Reusable Box HttpCurl Setup.
    curl.i = CkHttpCurl::ckCreate()
    If curl.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkHttpCurl::ckSetVar(curl,"access_token","BOX_ACCESS_TOKEN")
    CkHttpCurl::ckSetVar(curl,"parent_name","/")
    ;  Box's fixed root ID is an implementation detail; callers supply names.
    CkHttpCurl::ckSetVar(curl,"parent_id","0")
    setupCommand.i = CkStringBuilder::ckCreate()
    If setupCommand.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    setupReplacements.i

    ;  Register findParent; registration sends no request.
    CkStringBuilder::ckSetString(setupCommand,"curl -X GET " + Chr(34) + "https://api.box.com/2.0/folders/0/items?limit=1000&fields=id,type,name" + Chr(34) + " -H " + Chr(34) + "Authorization: Bearer ACCESS_TOKEN" + Chr(34))
    setupReplacements = CkStringBuilder::ckReplace(setupCommand,"ACCESS_TOKEN",CkHttpCurl::ckGetVar(curl,"access_token"))
    success = CkHttpCurl::ckAddFunction(curl,"findParent",CkStringBuilder::ckGetAsString(setupCommand))
    If success <> 1
        Debug CkHttpCurl::ckLastErrorText(curl)
        CkHttpCurl::ckDispose(curl)
        CkStringBuilder::ckDispose(setupCommand)
        ProcedureReturn
    EndIf

    ;  Register findFolder; registration sends no request.
    CkStringBuilder::ckSetString(setupCommand,"curl -X GET " + Chr(34) + "https://api.box.com/2.0/folders/{{parent_id}}/items?limit=1000&fields=id,type,name" + Chr(34) + " -H " + Chr(34) + "Authorization: Bearer ACCESS_TOKEN" + Chr(34))
    setupReplacements = CkStringBuilder::ckReplace(setupCommand,"ACCESS_TOKEN",CkHttpCurl::ckGetVar(curl,"access_token"))
    success = CkHttpCurl::ckAddFunction(curl,"findFolder",CkStringBuilder::ckGetAsString(setupCommand))
    If success <> 1
        Debug CkHttpCurl::ckLastErrorText(curl)
        CkHttpCurl::ckDispose(curl)
        CkStringBuilder::ckDispose(setupCommand)
        ProcedureReturn
    EndIf

    ;  Register findFile; registration sends no request.
    CkStringBuilder::ckSetString(setupCommand,"curl -X GET " + Chr(34) + "https://api.box.com/2.0/folders/{{folder_id}}/items?limit=1000&fields=id,type,name" + Chr(34) + " -H " + Chr(34) + "Authorization: Bearer ACCESS_TOKEN" + Chr(34))
    setupReplacements = CkStringBuilder::ckReplace(setupCommand,"ACCESS_TOKEN",CkHttpCurl::ckGetVar(curl,"access_token"))
    success = CkHttpCurl::ckAddFunction(curl,"findFile",CkStringBuilder::ckGetAsString(setupCommand))
    If success <> 1
        Debug CkHttpCurl::ckLastErrorText(curl)
        CkHttpCurl::ckDispose(curl)
        CkStringBuilder::ckDispose(setupCommand)
        ProcedureReturn
    EndIf

    ;  Register findDestination; registration sends no request.
    CkStringBuilder::ckSetString(setupCommand,"curl -X GET " + Chr(34) + "https://api.box.com/2.0/folders/0/items?limit=1000&fields=id,type,name" + Chr(34) + " -H " + Chr(34) + "Authorization: Bearer ACCESS_TOKEN" + Chr(34))
    setupReplacements = CkStringBuilder::ckReplace(setupCommand,"ACCESS_TOKEN",CkHttpCurl::ckGetVar(curl,"access_token"))
    success = CkHttpCurl::ckAddFunction(curl,"findDestination",CkStringBuilder::ckGetAsString(setupCommand))
    If success <> 1
        Debug CkHttpCurl::ckLastErrorText(curl)
        CkHttpCurl::ckDispose(curl)
        CkStringBuilder::ckDispose(setupCommand)
        ProcedureReturn
    EndIf

    ;  Register getFileDetails; registration sends no request.
    CkStringBuilder::ckSetString(setupCommand,"curl -X GET " + Chr(34) + "https://api.box.com/2.0/files/{{file_id}}?fields=id,sha1,file_version" + Chr(34) + " -H " + Chr(34) + "Authorization: Bearer ACCESS_TOKEN" + Chr(34))
    setupReplacements = CkStringBuilder::ckReplace(setupCommand,"ACCESS_TOKEN",CkHttpCurl::ckGetVar(curl,"access_token"))
    success = CkHttpCurl::ckAddFunction(curl,"getFileDetails",CkStringBuilder::ckGetAsString(setupCommand))
    If success <> 1
        Debug CkHttpCurl::ckLastErrorText(curl)
        CkHttpCurl::ckDispose(curl)
        CkStringBuilder::ckDispose(setupCommand)
        ProcedureReturn
    EndIf

    ;  Register getEnterprise; registration sends no request.
    CkStringBuilder::ckSetString(setupCommand,"curl -X GET " + Chr(34) + "https://api.box.com/2.0/users/me?fields=enterprise" + Chr(34) + " -H " + Chr(34) + "Authorization: Bearer ACCESS_TOKEN" + Chr(34))
    setupReplacements = CkStringBuilder::ckReplace(setupCommand,"ACCESS_TOKEN",CkHttpCurl::ckGetVar(curl,"access_token"))
    success = CkHttpCurl::ckAddFunction(curl,"getEnterprise",CkStringBuilder::ckGetAsString(setupCommand))
    If success <> 1
        Debug CkHttpCurl::ckLastErrorText(curl)
        CkHttpCurl::ckDispose(curl)
        CkStringBuilder::ckDispose(setupCommand)
        ProcedureReturn
    EndIf

    ;  Register output rules once. Chilkat 11.7.0 evaluates {{name}} variables
    ;  when extracting each output, using the current value at that time.
    success = CkHttpCurl::ckAddOutput2(curl,"findParent","entries","name","{{parent_name}}",1,"id","parent_id")
    If success <> 1
        Debug CkHttpCurl::ckLastErrorText(curl)
        CkHttpCurl::ckDispose(curl)
        CkStringBuilder::ckDispose(setupCommand)
        ProcedureReturn
    EndIf

    success = CkHttpCurl::ckAddOutput2(curl,"findFolder","entries","name","{{folder_name}}",1,"id","folder_id")
    If success <> 1
        Debug CkHttpCurl::ckLastErrorText(curl)
        CkHttpCurl::ckDispose(curl)
        CkStringBuilder::ckDispose(setupCommand)
        ProcedureReturn
    EndIf

    success = CkHttpCurl::ckAddOutput2(curl,"findFile","entries","name","{{file_name}}",1,"id","file_id")
    If success <> 1
        Debug CkHttpCurl::ckLastErrorText(curl)
        CkHttpCurl::ckDispose(curl)
        CkStringBuilder::ckDispose(setupCommand)
        ProcedureReturn
    EndIf

    success = CkHttpCurl::ckAddOutput2(curl,"findDestination","entries","name","{{destination_name}}",1,"id","destination_id")
    If success <> 1
        Debug CkHttpCurl::ckLastErrorText(curl)
        CkHttpCurl::ckDispose(curl)
        CkStringBuilder::ckDispose(setupCommand)
        ProcedureReturn
    EndIf

    success = CkHttpCurl::ckAddOutput(curl,"getFileDetails","file_version.id","file_version_id")
    If success <> 1
        Debug CkHttpCurl::ckLastErrorText(curl)
        CkHttpCurl::ckDispose(curl)
        CkStringBuilder::ckDispose(setupCommand)
        ProcedureReturn
    EndIf

    success = CkHttpCurl::ckAddOutput(curl,"getFileDetails","sha1","file_sha1")
    If success <> 1
        Debug CkHttpCurl::ckLastErrorText(curl)
        CkHttpCurl::ckDispose(curl)
        CkStringBuilder::ckDispose(setupCommand)
        ProcedureReturn
    EndIf

    success = CkHttpCurl::ckAddOutput(curl,"getEnterprise","enterprise.id","enterprise_id")
    If success <> 1
        Debug CkHttpCurl::ckLastErrorText(curl)
        CkHttpCurl::ckDispose(curl)
        CkStringBuilder::ckDispose(setupCommand)
        ProcedureReturn
    EndIf

    ;  END ONE-TIME SETUP
    ;  The name lookups below assume each listing fits in one page (1000 items).
    ;  Parent and destination names select root children; folder_name selects a child
    ;  of parent_name. "/" selects the root parent. These are not arbitrary paths.

    ;  BEGIN OPERATION -- keep the configured object when reusing it.
    ;  Inputs are names. Retain cached IDs when the selected names have not changed.
    parentName.s = "/"
    folderName.s = "images"
    fileName.s = "penguins.jpg"
    If (CkHttpCurl::ckGetVar(curl,"parent_name") <> parentName) OR ((parentName = "/") AND (CkHttpCurl::ckVarDefined(curl,"parent_id") = 0))
        CkHttpCurl::ckSetVar(curl,"parent_name",parentName)
        CkHttpCurl::ckClearVar(curl,"parent_id")
        CkHttpCurl::ckClearVar(curl,"folder_id")
        CkHttpCurl::ckClearVar(curl,"file_id")
        CkHttpCurl::ckClearVar(curl,"file_version_id")
        CkHttpCurl::ckClearVar(curl,"file_sha1")
        If parentName = "/"
            CkHttpCurl::ckSetVar(curl,"parent_id","0")
        EndIf

    EndIf

    If CkHttpCurl::ckGetVar(curl,"folder_name") <> folderName
        CkHttpCurl::ckSetVar(curl,"folder_name",folderName)
        CkHttpCurl::ckClearVar(curl,"folder_id")
        CkHttpCurl::ckClearVar(curl,"file_id")
        CkHttpCurl::ckClearVar(curl,"file_version_id")
        CkHttpCurl::ckClearVar(curl,"file_sha1")
    EndIf

    If CkHttpCurl::ckGetVar(curl,"file_name") <> fileName
        CkHttpCurl::ckSetVar(curl,"file_name",fileName)
        CkHttpCurl::ckClearVar(curl,"file_id")
        CkHttpCurl::ckClearVar(curl,"file_version_id")
        CkHttpCurl::ckClearVar(curl,"file_sha1")
    EndIf

    CkHttpCurl::ckSetVar(curl,"local_path","qa_output/penguins-verified.jpg")
    ;  file_version_id is also unknown, so getFileDetails becomes a prerequisite.
    ;  Its AddOutput mappings cache both the selected version and its SHA-1.
    CkHttpCurl::ckClearTargetOutput(curl,"*")
    authorizedCommand1.i = CkStringBuilder::ckCreate()
    If authorizedCommand1.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkStringBuilder::ckSetString(authorizedCommand1,"curl -X GET " + Chr(34) + "https://api.box.com/2.0/files/{{file_id}}/content?version={{file_version_id}}" + Chr(34) + " -H " + Chr(34) + "Authorization: Bearer {{access_token}}" + Chr(34) + " -L -o " + Chr(34) + "{{local_path}}" + Chr(34))
    headerReplacement1.i = CkStringBuilder::ckReplace(authorizedCommand1,"{{access_token}}",CkHttpCurl::ckGetVar(curl,"access_token"))
    success = CkHttpCurl::ckDoYourThing(curl,CkStringBuilder::ckGetAsString(authorizedCommand1))
    If (success <> 1) OR (CkHttpCurl::ckStatusCode(curl) <> 200)
        Debug "Box request failed. HTTP status: " + Str(CkHttpCurl::ckStatusCode(curl))
        Debug "Failure reason: " + Str(CkHttpCurl::ckFailReason(curl))
        Debug CkHttpCurl::ckResponseBodyStr(curl)
        CkHttpCurl::ckDispose(curl)
        CkStringBuilder::ckDispose(setupCommand)
        CkStringBuilder::ckDispose(authorizedCommand1)
        ProcedureReturn
    EndIf

    digest.i = CkCrypt2::ckCreate()
    If digest.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkCrypt2::setCkHashAlgorithm(digest, "sha1")
    CkCrypt2::setCkEncodingMode(digest, "hex_lower")
    actualSha1.s = CkCrypt2::ckHashFileENC(digest,CkHttpCurl::ckGetVar(curl,"local_path"))
    If CkCrypt2::ckLastMethodSuccess(digest) <> 1
        Debug CkCrypt2::ckLastErrorText(digest)
        CkHttpCurl::ckDispose(curl)
        CkStringBuilder::ckDispose(setupCommand)
        CkStringBuilder::ckDispose(authorizedCommand1)
        CkCrypt2::ckDispose(digest)
        ProcedureReturn
    EndIf

    If actualSha1 <> CkHttpCurl::ckGetVar(curl,"file_sha1")
        Debug "Downloaded content did not match the selected version's SHA-1."
        CkHttpCurl::ckDispose(curl)
        CkStringBuilder::ckDispose(setupCommand)
        CkStringBuilder::ckDispose(authorizedCommand1)
        CkCrypt2::ckDispose(digest)
        ProcedureReturn
    EndIf

    Debug "Version-specific download verified."


    CkHttpCurl::ckDispose(curl)
    CkStringBuilder::ckDispose(setupCommand)
    CkStringBuilder::ckDispose(authorizedCommand1)
    CkCrypt2::ckDispose(digest)


    ProcedureReturn
EndProcedure