Box: Resolve Folder and File IDs with the HttpCurl Dependency Engine

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. Download images/penguins.jpg by name with one DoYourThing call. The engine runs only the intermediate requests required by unknown inputs. A cold plan is findFolder, findFile, targetCurl; root parent_id is a fixed convention.

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

var success = false;

//  Requires Chilkat 11.5.0 or later and a previously unlocked Chilkat bundle.
//  See Global Unlock Sample.
//  Guide: Box API Guide.

success = false;

//  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.
var curl = new CkHttpCurl();
curl.SetVar("access_token","BOX_ACCESS_TOKEN");
curl.SetVar("parent_name","/");
curl.SetVar("folder_name","images");
curl.SetVar("file_name","penguins.jpg");
curl.SetVar("destination_name","archive");
//  Box's fixed root ID is an implementation detail; callers supply names.
curl.SetVar("parent_id","0");
var setupCommand = new CkStringBuilder();
var setupReplacements;

//  Register findParent; registration sends no request.
setupCommand.SetString("curl -X GET \"https://api.box.com/2.0/folders/0/items?limit=1000&fields=id,type,name\" -H \"Authorization: Bearer ACCESS_TOKEN\"");
setupReplacements = setupCommand.Replace("ACCESS_TOKEN",curl.GetVar("access_token"));
success = curl.AddFunction("findParent",setupCommand.GetAsString());
if (success !== true) {
    console.log(curl.LastErrorText);
    return;
}

//  Register findFolder; registration sends no request.
setupCommand.SetString("curl -X GET \"https://api.box.com/2.0/folders/{{parent_id}}/items?limit=1000&fields=id,type,name\" -H \"Authorization: Bearer ACCESS_TOKEN\"");
setupReplacements = setupCommand.Replace("ACCESS_TOKEN",curl.GetVar("access_token"));
success = curl.AddFunction("findFolder",setupCommand.GetAsString());
if (success !== true) {
    console.log(curl.LastErrorText);
    return;
}

//  Register findFile; registration sends no request.
setupCommand.SetString("curl -X GET \"https://api.box.com/2.0/folders/{{folder_id}}/items?limit=1000&fields=id,type,name\" -H \"Authorization: Bearer ACCESS_TOKEN\"");
setupReplacements = setupCommand.Replace("ACCESS_TOKEN",curl.GetVar("access_token"));
success = curl.AddFunction("findFile",setupCommand.GetAsString());
if (success !== true) {
    console.log(curl.LastErrorText);
    return;
}

//  Register findDestination; registration sends no request.
setupCommand.SetString("curl -X GET \"https://api.box.com/2.0/folders/0/items?limit=1000&fields=id,type,name\" -H \"Authorization: Bearer ACCESS_TOKEN\"");
setupReplacements = setupCommand.Replace("ACCESS_TOKEN",curl.GetVar("access_token"));
success = curl.AddFunction("findDestination",setupCommand.GetAsString());
if (success !== true) {
    console.log(curl.LastErrorText);
    return;
}

//  Register getFileDetails; registration sends no request.
setupCommand.SetString("curl -X GET \"https://api.box.com/2.0/files/{{file_id}}?fields=id,sha1,file_version\" -H \"Authorization: Bearer ACCESS_TOKEN\"");
setupReplacements = setupCommand.Replace("ACCESS_TOKEN",curl.GetVar("access_token"));
success = curl.AddFunction("getFileDetails",setupCommand.GetAsString());
if (success !== true) {
    console.log(curl.LastErrorText);
    return;
}

//  Register getEnterprise; registration sends no request.
setupCommand.SetString("curl -X GET \"https://api.box.com/2.0/users/me?fields=enterprise\" -H \"Authorization: Bearer ACCESS_TOKEN\"");
setupReplacements = setupCommand.Replace("ACCESS_TOKEN",curl.GetVar("access_token"));
success = curl.AddFunction("getEnterprise",setupCommand.GetAsString());
if (success !== true) {
    console.log(curl.LastErrorText);
    return;
}

//  Initial name selections. AddOutput2 stores these WHERE values literally.
success = curl.AddOutput2("findParent","entries","name",curl.GetVar("parent_name"),true,"id","parent_id");
if (success !== true) {
    console.log(curl.LastErrorText);
    return;
}

success = curl.AddOutput2("findFolder","entries","name",curl.GetVar("folder_name"),true,"id","folder_id");
if (success !== true) {
    console.log(curl.LastErrorText);
    return;
}

success = curl.AddOutput2("findFile","entries","name",curl.GetVar("file_name"),true,"id","file_id");
if (success !== true) {
    console.log(curl.LastErrorText);
    return;
}

success = curl.AddOutput2("findDestination","entries","name",curl.GetVar("destination_name"),true,"id","destination_id");
if (success !== true) {
    console.log(curl.LastErrorText);
    return;
}

success = curl.AddOutput("getFileDetails","file_version.id","file_version_id");
if (success !== true) {
    console.log(curl.LastErrorText);
    return;
}

success = curl.AddOutput("getFileDetails","sha1","file_sha1");
if (success !== true) {
    console.log(curl.LastErrorText);
    return;
}

success = curl.AddOutput("getEnterprise","enterprise.id","enterprise_id");
if (success !== true) {
    console.log(curl.LastErrorText);
    return;
}

//  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.
var parentName = "/";
var folderName = "images";
var fileName = "penguins.jpg";
if ((curl.GetVar("parent_name") !== parentName) || ((parentName == "/") && (curl.VarDefined("parent_id") == false))) {
    curl.SetVar("parent_name",parentName);
    curl.ClearVar("parent_id");
    curl.ClearVar("folder_id");
    curl.ClearVar("file_id");
    curl.ClearVar("file_version_id");
    curl.ClearVar("file_sha1");
    if (parentName == "/") {
        curl.SetVar("parent_id","0");
    }
    else {
        success = curl.AddOutput2("findParent","entries","name",curl.GetVar("parent_name"),true,"id","parent_id");
        if (success !== true) {
            console.log(curl.LastErrorText);
            return;
        }

    }

}

if (curl.GetVar("folder_name") !== folderName) {
    curl.SetVar("folder_name",folderName);
    curl.ClearVar("folder_id");
    curl.ClearVar("file_id");
    curl.ClearVar("file_version_id");
    curl.ClearVar("file_sha1");
    success = curl.AddOutput2("findFolder","entries","name",curl.GetVar("folder_name"),true,"id","folder_id");
    if (success !== true) {
        console.log(curl.LastErrorText);
        return;
    }

}

if (curl.GetVar("file_name") !== fileName) {
    curl.SetVar("file_name",fileName);
    curl.ClearVar("file_id");
    curl.ClearVar("file_version_id");
    curl.ClearVar("file_sha1");
    success = curl.AddOutput2("findFile","entries","name",curl.GetVar("file_name"),true,"id","file_id");
    if (success !== true) {
        console.log(curl.LastErrorText);
        return;
    }

}

//  No manual lookup call: the final request asks for an unknown file_id.
var plan = new CkJsonObject();
plan.EmitCompact = false;
var authorizedCommand1 = new CkStringBuilder();
authorizedCommand1.SetString("curl -X GET \"https://api.box.com/2.0/files/{{file_id}}/content\" -H \"Authorization: Bearer {{access_token}}\" -L -o \"qa_output/penguins.jpg\"");
var headerReplacement1 = authorizedCommand1.Replace("{{access_token}}",curl.GetVar("access_token"));
success = curl.ExaminePlan(authorizedCommand1.GetAsString(),plan);
if (success !== true) {
    console.log(curl.LastErrorText);
    return;
}

console.log(plan.Emit());
curl.ClearTargetOutput("*");
var authorizedCommand2 = new CkStringBuilder();
authorizedCommand2.SetString("curl -X GET \"https://api.box.com/2.0/files/{{file_id}}/content\" -H \"Authorization: Bearer {{access_token}}\" -L -o \"qa_output/penguins.jpg\"");
var headerReplacement2 = authorizedCommand2.Replace("{{access_token}}",curl.GetVar("access_token"));
success = curl.DoYourThing(authorizedCommand2.GetAsString());
if ((success !== true) || (curl.StatusCode !== 200)) {
    console.log("Box request failed. HTTP status: " + curl.StatusCode);
    console.log("Failure reason: " + curl.FailReason);
    console.log(curl.ResponseBodyStr);
    return;
}

console.log("Downloaded to qa_output/penguins.jpg");