Guessing root causes

Ketika muncul suatu masalah, sering kita hanya dapat mengenali gejala. Dan kemudian melakukan perbaikan berdasarkan gejala tadi. Dan hanya kadang-kadang kita dapat mengenalil root cause, sehingga dapat melakukan perbaikan yang lebih menyeluruh. Seperti hari ini, seorang pengembang mengalami masalah tidak dapat melakukan pembuatan web service di sistem SAP Development. Sebelumnya, di sistem lain yang mirip sandbox, pembuatan web service ini sudah pernah dilakukan. Karena dulu sempet nulis di Wiki, saya jadi bisa ingat lagi kejadian-kejadian ketika dahulu mengaktifkan Web Service di mesin yang lama. Dan jadi ketahuan ada satu langkah yang belum dilakukan. Tetapi.. knowledge milik kita sendiri hanya bisa membantu sejauh itu, tetap belum dapat diaktifkan, si web service itu. Dari transaksi SE80, membuka function group yang tepat, kemudian klik kanan, create web service.. gagal di langkah terakhir wizard.
Transaksi SU53, melihat event kegagalan authorization terakhir .. didapatlah authorization object yang diperlukan untuk melanjutkan step pembuatan web service. Namun setelah authorization object ini didapat, muncul kegagalan berikutnya.. dan lewat SU53 lagi, didapat satu authorization object yang lain, yang belum dimiliki user kita.
This is getting tiresome, mengingat proses memberikan authorization object ke user harus melewati pihak lain, dan kadang-kadang harus menunggu surat-menyurat (you know, some things must be official). Akhirnya kembali ke Google, memanfaatkan pengetahuan kolektif umat manusia (ceile..). Aku mengharapkan menemukan list authorization object yang lengkap di situ. Sayangnya mr Google hanya menemukan halaman yang publik di Internet, dan tidak ada informasi definitif mengenai daftar authorization object di situ.. tapi sebuah keyword yang ultra-important di dunia SAP menarik perhatianku di antara hasil search Google : 'according to SAP Notes 913944 ...'. SAP Notes adalah elemen dari knowledge base SAP, yang hanya bisa dibuka oleh customer terdaftar SAP. Menggunakan login Bos, ke website SAP, pilih SAP notes, masukkan 913944.. voila: muncul list of authorization objects yang diperlukan untuk membuat 'Web Services Datasource'. By interpolation, object2 di situ juga akan bermanfaat kalau kita hanya ingin membuat 'Web Services'..
Could you guess what the root cause are?
Btw, cara-cara serupa di atas juga aku lakukan ketika mencoba memanggil SAP RFC via JCo library, dan kebetulan user yg digunakan untuk RFC tidak memiliki semua authentication objects yang diperlukan..

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